中国生态农业学报(中英文)

Yield and inter-specific interactions in maize/chickpea intercrop under different application rates of P in irrigated sierozem along the Yellow River in Northwest China

LAN Yu-Feng, LIU Hong-Liang, YANG Si-Cun, SONG Jian-Guo, LI Long

2010, 18(5): 917-922. doi: 10.3724/SP.J.1011.2010.00917

Abstract(1703) PDF(1501)

Abstract:
The effects of application of different rates of phosphorous on rhizospheric soil processes and yield of maize and chickpea under mono-cropping and intercropping systems were studied in irrigated low Olsen-P sierozem along the Yellow River in Northwest China. The results show that zero (P0) or 40 kg·hm^-2 (P40) P application of maize/chickpea intercrop gives LER (land equivalent ratio) of biomass and grain yield less than 1.00. This implies intercropping disadvantage at P0 or P40, which is mainly due to reduction of chickpea yield. At P application rate of 80 kg·hm^-2 (P80), biomass and grain yield LERs are greater 1.00, implying intercropping advantage.Yield of intercropped maize is 3%, 12% and 19% higher than that of mono-cropped maize at P0, P40 and P80 respectively. Yield of intercropped chickpea at P0 and P40 are significantly lower than that of mono-cropped chickpea. Aggressivity of maize for water, nutrients and other resources is stronger than that of chickpea (A_mc>0) during the co-growth period of two crops. The dynamic curve of chickpea growth indicates that the aggressivity is more significant under P0 and P40 treatments. Harvest index (HI) of intercropped maize is higher than that of mono-cropped maize, and that of intercropped chickpea is less than that of mono-cropped at different P levels. There is no indication that intercropping chickpea enhances organic P utilization by maize. Acid phosphatase activity for intercropped chickpea at P0 is lower than that for the mono-cropped. No advantage is noted under intercropping at P0 and P40. However intercrop advantage is observed at P80.

Effect of combination use of Zn and N fertilizers on yield and Zn content in winter wheat

LU Xin-Chun, TIAN Xiao-Hong, YANG Xi-Wen, MAI Wen-Xuan, ZHAO Ai-Qing, BAO Qiong-Li

2010, 18(5): 923-928. doi: 10.3724/SP.J.1011.2010.00923

Abstract(1490) PDF(1237)

Abstract:
A two-year experiment was conducted to investigate the effects of combination use of Zn and N fertilizers on growth and Zn content in 10 varieties of winter wheat in calcareous soils. Results show that the effects of sole application of Zn fertilizer and combination use of Zn and N fertilizers on yield and grain Zn content are significantly different among various varieties of winter wheat. Soil content of DTPA-Zn significantly increases in Zn or Zn and N fertilizers treatments. Zn significantly increases grain Zn content in “Xiza No. 1”, “Wunong148”, and “Zhengmai 9023”. Application of Zn and N increases grain Zn content by 7.3%~54.7% in 9 genotypes of wheat, excluding “Xiaoyan 22”. Zn fertilizer application does not significantly increase Zn uptake of wheat. However, the combination application of Zn and N increases Zn shoot content by 6.5% in the first year and by 29.8% in the second year of the experiment. N fertilization remarkably increases Zn uptake of wheat, but Zn accumulation is mainly in stems and leaves. In calcareous soils, Zn fertilizer application significantly increases soil DTPA-Zn content. However, the effect of Zn on yield and grain Zn content is insignificant. Combination use of Zn and N fertilizers in calcareous soils increase wheat yield and grain Zn content.

Effect of slow-release compound fertilizer on nitrogen nutrient in soil and ryegrass

ZHU Hong-Xia, DONG Yan, WANG Zheng-Yin

2010, 18(5): 929-933. doi: 10.3724/SP.J.1011.2010.00929

Abstract(1500) PDF(1253)

Abstract:
Soil incubation and pot-experiment methods were used to study the effects of uncoated slow-release compound fertilizer (SRCF) on forms of soil nitrogen (NH₄⁺-N, NO₃^－-N, alkali-hydrolysis N, microbial nitrogen and fixed-ammonium) and nitrogen content of ryegrass. The results indicate that the trend of soil NH₄⁺-N in CCF (common compound fertilizer) and SRCF treatments has uni-modal curve. Soil NH₄⁺-N in SRCF is higher than that in CCF treatment in the middle and final incubation period. However, soil NO₃^－-N in SRCF1 is lower than that in CCF1 treatment. Also soil NO₃^－-N in SRCF2 is higher in the early incubation period and lower in the latter period than that in CCF1 treatment. The trend of alkali-hydrolysis N and soil microbial nitrogen (SMBN) in SRCF treatments exhibits a di-modal curve, with peaks respectively appearing on the 21st and 105th day of incubation. Variations in soil fixed-ammonium are consistent and minimal. Soil ammonium fixation in SRCF is higher than that in CCF treatment. The height, biomass, dry-weight and nitrogen content of ryegrass in SRCF1-3 treatment are higher than those in CCF1 treatment. In comparison with CCF, SRCF treatment is more suitable in terms of ryegrass nitrogen uptake and yield under the same nutrient conditions. Ryegrass nitrogen uptake is negatively correlated with soil NH₄⁺-N and SMBN. It is, however, positively correlated with NO₃^－-N and fixed-ammonium.

Effects of four fumigants on soil nitrogen transformation

YAN Dong-Dong, WANG Qiu-Xia, GUO Mei-Xia, GUO Zhang-Bi, CAO Ao-Cheng

2010, 18(5): 934-938. doi: 10.3724/SP.J.1011.2010.00934

Abstract(1544) PDF(1686)

Abstract:
With laboratory incubation method at constant temperature under aerated conditions, the effects of 4 fumigants [Chloropicrin (Pic), methyl iodide (MeI), 1,3-dichloropropene (1,3-D) and methyl disulfide (DMDS) on soil N mineralization and nitrification under vegetable greenhouse conditions in Beijing area were studied. The results reveal that mineral N concentration increases significantly in a short-term period after fumigant treatment. Cumulative N mineralization under 1,3-D, MeI, DMDS and Pic treatments are 320.62 mg·kg^-1, 317.25 mg·kg^-1, 287.87 mg·kg^-1 and 278.73 mg·kg^-1 respectively. This represents corresponding increases of 68.85%, 67.07%, 51.60% and 46.78% compared with untreated soils (189.89 mg·kg^-1). Fumigation strongly inhibits nitrification. Compared with the control, ammonium nitrogen content increases after fumigation. MeI treatment has the highest ammonium nitrogen (194.97 mg·kg^-1) and control treatment has the lowest (28.82 mg·kg^-1). Nitrification inhibition rates by Pic, 1,3-D, DMDS, MeI treatments are 40.8%, 20.8%, 26.9% and 24.1% respectively. Nitrification is inhibited for at least 2 weeks after treatment with Pic, 1,3-D and MeI, and at least for 1 week after treatment with DMDS. Nitrification and mineralization gradually recover under long-term incubation.

Effect of bacterial manure on soil biological activity, yield and quality of rape in reclaimed core-mining areas

LI Li, HONG Jian-Ping, XIE Ying-He, YANG Yan, ZHANG Lu

2010, 18(5): 939-944. doi: 10.3724/SP.J.1011.2010.00939

Abstract(1678) PDF(1245)

Abstract:
A pot experiment was conducted with a randomized complete block design to investigate the effects of different levels of bacterial manure on soil biochemical reaction, enzyme activity and rape yield and quality in reclaimed core-mining soils under combination application of organic and chemical fertilizers. The results show that bacterial manure increases soil biochemical reaction thereby enhancing soil enzyme activity. Soil respiration rate, ammonification and nitrification intensity, as well as catalase (CAT) activity under bacterial manure treatment are significantly (P<0.05) higher than those under the control. When the content of bacterial manure exceeds 0.04 g·kg^-1(soil), significant differences (P<0.05) are observed between the treatment and control in the activities of urease and sucrose. Besides, bacterial manure enhances rape production and quality. There are significant (P<0.05) differences between treatment and control in average dry-weight of individual plants and in contents of nitrate and reducing sugar. When the level of bacterial manure exceeds 0.04 g·kg^-1(soil), the content of Vc significantly (P<0.05) outweighs the control. When the level of bacterial manure is less than 0.08 g·kg^-1 soil, no significant differences are noted between treatment and control in fresh-weights of individual plants. The study indicates that bacterial manure positively influences soil biological activity and rape quality in reclaimed core-mining areas.

Response of super hybrid rice “Y Liangyou No. 1” to N-fertilizer dose and its N use efficiency

CUI Xin-Wei, ZHU Xiao-Qi, LONG Shi-Ping, JI Xiong-Hui, SHI Li-Hong, PENG Zhi-Hong, LI Hong-Shun

2010, 18(5): 945-949. doi: 10.3724/SP.J.1011.2010.00945

Abstract(1524) PDF(1378)

Abstract:
Six doses of N [0 kg·hm^-2 (N0), 90 kg·hm^-2 (N1), 135 kg·hm^-2 (N2), 180 kg·hm^-2 (N3), 225 kg·hm^-2 (N4) and 270 kg·hm^-2 (N5)] were used to compare grain yield composition and N use efficiency of “Y Liangyou No. 1” super hybrid rice. Based on the model of N dose-yield, yield is highest (11.42 t·hm^-2) at N application rate 245.9 kg·hm^-2. On the other hand, economic benefit is highest at 213.5 kg·hm^-2 N amount due to the harmony between rice yield and N use efficiency. A Logistic model was used to simulate dynamic of total biomass production under different N doses. Though there exist different models for different N doses, total biomass generally increases rapidly at grain-filling stage. With increasing N dose, N recovery efficiency (NRE) and N agronomic efficiency (NAE) continuously decrease, but at different degrees. However, N4 treatment gives the best conditions for N dose, grain yield and N-fertilizer use efficiency. It has the highest yield and N-fertilizer use efficiency. As 20% total N dose for earing fertilizer does not meet grain-filling requirement, it is suggested to increase N application rate at booting stage of super hybrid rice cultivation.

Effect of nitrate concentration on proton release by faba-bean roots

MAO Jia, XU Ren-Kou, WAN Qing, CHEN Rong-Fu, LI Xing-Hui, SHEN Ren-Fang

2010, 18(5): 950-953. doi: 10.3724/SP.J.1011.2010.00950

Abstract(1424) PDF(1088)

Abstract:
In the effort to understand the mechanisms of enhanced soil acidification by legume plants, the effect of nitrate dose on proton release by the roots of faba-bean under medium pH conditions was analyzed in solution culture experiment and by automatic potentiometric titration at a constant pH. The results show that the roots of faba-bean release the largest amount of protons when no external nitrate source is available, inducing a drastic decline (1.93 units) in medium pH. The cumulative amount of released proton after ten incubations reaches 37.5 mmol per gram dry-root. With increasing nitrate concentration, the amount of released protons and change in medium pH decrease. When nitrate concentration increases to 1.0 mmol·L^-1, only a small amount of proton is released at the early stage of the culture experiment (in fact, some amount of OH^- is released at the later stage of the experiment). When there is no external nitrate or it is available at low levels, legume plants derive N from biological nitrogen fixation, leading to higher cation than anion uptake. Under this condition, plant roots release protons to ensure that the charges are well in balance. Results also indicate that protons in the culture solutions come mainly from direct releases by faba-bean roots. The effect of organic acid on the amounts of proton in the medium is generally negligible. Addition of nitrate can reduce H+ release by faba-bean roots.

Abundance of ammonia-oxidizer and potential nitrification rate of quaternary red-clay paddy soil during rice growth

SONG Ya-Na, CHEN Zai-Jie, LIN Zhi-Min

2010, 18(5): 954-958. doi: 10.3724/SP.J.1011.2010.00954

Abstract(1557) PDF(1955)

Abstract:
The amount of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in quaternary red-clay paddy soils during rice growing season were determined by real-time polymerase chain reaction (RT-PCR) using amoA gene assay copies. The potential nitrification rate of soil was investigated too. Results show that AOA is the dominant ammonia-oxidizer in quaternary red-clay paddy soils, with AOA/AOB amoA gene ratio range of 1.6~120.7. There is a higher abundance of AOA in root-zone soils than in surface soils. The amount of AOA in surface and root-zone soils increases with growth stage of rice, which is more evident in root-zone soils. There is a higher abundance of AOB in surface soils than in root-zone soils at the early growth stage, with obvious enhancement of root-zone AOB after booting stage. Root-zone AOB is much abundant at the late growth stage of rice. Potential nitrification rate gradually increases with time during rice growing season, especially in root-zone soils. Potential nitrification rates in root-zone soils exhibit significant positive correlations with AOB and AOA amounts. However, potential nitrification rates in surface soils are only significantly positively correlated with AOA amount. The findings of this study indicate the dominance of AOA, which is more strongly related with quaternary red-clay paddy soil nitrification. The results further demonstrate the importance of ammonia-oxidizers in microbial composition and ecological functions of paddy soils.

Effect of sowing date and density on sink/source relationship and canopy light transmission of summer maize (Zea mays L.)

LI Ning, ZHAI Zhi-Xi, LI Jian-Min, DUAN Liu-Sheng, LI Zhao-Hu

2010, 18(5): 959-964. doi: 10.3724/SP.J.1011.2010.00959

Abstract(1467) PDF(1729)

Abstract:
An experiment involving 2 cultivars, and 3 sowing dates and densities was conducted in Laizhou Experimental Station of China Agricultural University in 2008~2009 with the objective of selecting the optimum cultivation pattern. The effects of sowing date and density on sink/source relationship and canopy light transmission of summer maize population were also analyzed in the experiment. The results indicate higher sink/source indices under sowing date before June 22 at a density of 6.00×10⁴~ 7.50×10⁴·hm^-2 (semi-compact variety “Jinhai No. 5”) or 6.75×10⁴~8.25×10⁴·hm^-2 (compact variety “Zhengdan 958”). At this rate, LAI is 4.88~5.97 at silking and 2.73~4.48 at maturity stage, light transmission is 21.09%~34.82% at silking and 27.97%~35.29% at maturity stage, ear-leaf Pn is 34.4~41.7 μmol(CO₂)·m^-2·s^-1. The optimum yield is 14 863.50 kg·hm^-2 for “Jinhai No. 5” sowed at June 15~17 with 7.50×10⁴·hm^-2 density, and 15 123.30 kg·hm^-2 for “Zhengdan 958” sowed at June 15~17 with 8.25×10⁴·hm^-2 density.

A biomass accumulation model for maize/soybean intercropping system

GAO Yang, DUAN Ai-Wang, QIU Xin-Qiang, ZHANG Jun-Peng, CHEN Jin-Ping, WANG He-Zhou

2010, 18(5): 965-968. doi: 10.3724/SP.J.1011.2010.00965

Abstract(3592) PDF(1861)

Abstract:
In this study, a radiation interception and utilization model was developed through an experiment on maize/soybean intercropping systems with different intercropping proportions of maize and soybean to assess crop growth and yield. In the model, crop biomass and yield are calculated as functions of photosynthetic active radiation (PAR), radiation interception fraction (F) and radiation use efficiency (RUE). PAR is estimated from ratios of PAR to solar radiation (SR). F is calculated by using the Keating and Carberry equation. Time for emergence, flowering and maturity are determined by growing degree days (GDD) since planting. Results indicate that the model accurately simulates total biomass and yield of fully irrigated maize/soybean intercropping system.

Light interception and utilization of maize-capsicum strip relay intercrop

XU Qiang, CHENG Zhi-Hui, LU Tao, XIE Bao-Ying

2010, 18(5): 969-976. doi: 10.3724/SP.J.1011.2010.00969

Abstract(1770) PDF(1180)

Abstract:
Efficient use of photosynthetic active radiation (PAR) is a major yield advantage factor in relay intercropping. This study therefore analyzed the dynamic processes of leaf area index (LAI) and the interception and utilization mechanisms of PAR in a relay intercropping system of maize and capsicum. Three treatments (sole cropping maize, sole cropping capsicum, and relay intercropping maize/capsicum) were set up. The study shows that though LAI for relay intercropping maize/capsicum is slightly lower than that for sole cropping maize and sole cropping capsicum, it exhibits a uni-peak curve for the three cropping systems. Under relay intercropping with maize, capsicum canopy light extinction coefficient (k) decreases. There is a significant difference in intercepted PAR between maize/capsicum relay intercropping and maize or capsicum sole cropping. The PAR intercepted amounts under maize/capsicum relay intercropping system is 42.25% higher than the weighted mean of PAR for maize and capsicum sole cropping according to their relay intercropping proportion (0.788∶0.222). PAR use efficiency under maize/capsicum relay intercropping system is 39.51% higher than the weighted mean for maize and capsicum sole cropping. Dry-matter accumulation rate for relay intercropping maize is higher than that for sole cropping maize, whereas the opposite is the case for sole cropping capsicum. The fraction of dry-matter allocated to stems and branches in relay intercropping capsicum is slightly lower than that in sole cropping capsicum. However, the fractions of allocated dry-matter to roots and fruits in relay intercropping capsicum are respectively 2.8% and 2.6% higher than those in sole cropping capsicum. There is insignificant difference in the fractions of allocated dry-matter to the different organs between relay intercropping and sole cropping maize. The study consequently suggests that in comparison with mono-culture, high productivity of relay intercropping is fully explainable by increasing interception and use efficiency of PAR. Reasonable intercropping of crops therefore complements the interception and utilization of PAR in space and time.

Effect of water deficit on the development of vascular bundle system of wheat spike

XIAO Ting-Ting, LU Jin-Yin

2010, 18(5): 977-981. doi: 10.3724/SP.J.1011.2010.00977

Abstract(1334) PDF(1053)

Abstract:
A pot experiment and paraffin sections were used to determine the development and micro-structures of ear vascular bundle system of two wheat (Triticum aestivum L.) genotypes at the late growth stage under water deficit. The relationships between ear vascular micro-structures and carbon assimilate stagnation were also analyzed. The study shows a fan-shaped distribution of the newly formed vascular bundles near the rachis of “Pubing143” and “Xinong979” during anthesis. Away from the rachis is ellipse or other forms of distribution under normal and water-deficit conditions. The cells between the new and original vascular tissues increase to eventually form sclerenchyma. With the development of ear, some of the original and new vascular tissues spread out to the glume and rachilla. The branches afterwards spread out to the lemma, lodicule and palea of the first and subsequent flowers. The parameters of vascular bundle system (such as the number and area of large and small vascular bundles) from base to top of ear decreases under water deficit condition. This may be one of the reasons of carbon assimilate stagnation in the gulme and rachis. Spike grain weight declines and non-grain organ biomass increases significantly in the two wheat genotypes under water deficit condition. This is more obvious for “Pubing143”, genotype for rainfed areas.

Genotypic and environmental differences in grain contents of Zn, Fe, Mn and Cu and how they relate to wheat yield

JIANG Li-Na, HAO Bao-Zhen, ZHANG Dai-Jing, SHAO Yun, LI Chun-Xi

2010, 18(5): 982-987. doi: 10.3724/SP.J.1011.2010.00982

Abstract(1562) PDF(1218)

Abstract:
Grain content of micronutrients is crucial for wheat growth and dietetic health. High grain contents of micronutrients are beneficial to enhancing nutritional functions of grains and guaranteeing security of crop products. By using acid digestion and atomic absorption spectrophotometry, Zn, Fe, Mn and Cu contents were measured in the grains of 17 wheat varieties from 5 different regions in Henan Province. Genotypic and environmental differences in Zn, Fe, Mn and Cu contents in gains and their relation to yield characteristics were also analyzed. The study shows that grain contents of Zn, Fe, Mn and Cu are 38.39±12.57 μg·g^-1, 79.13±49.45 μg·g^-1, 35.24±11.72 μg·g^-1, and 4.84±0.78 μg·g^-1, respectively. The variation coefficient of grain Fe content is the highest and that of Cu is the lowest. Analysis of variance shows that the effects of genotype, environment and genotype/environment interaction (GEI) are significant (P<0.01). Whereas wheat grain content of Zn, Mn and Cu is largely influenced by environment, that of Fe is mainly driven by GEI. Varietal stability of grain micronutrient content was also analyzed using the Eberhart and Russell model. The analysis indicates that varieties, whose micronutrients contents are insensitive to environment, have lower grain micronutrient content and vice versa. Among the 17 varieties, “Pu99084” has the highest environmental stability. Correlation analysis shows a positive genetic correlation between micronutrient and protein contents. There is a negative genetic correlation between micronutrient content and 1000-grain weight. However, phenotypic correlation between micronutrient content and grain yield is positive. There exists the possibility for simultaneously improving grain contents of micronutrients, protein and yield.

Application of GGE biplot in spring wheat yield stability analysis in rainfed areas of China

CHANG Lei, CHAI Shou-Xi

2010, 18(5): 988-994. doi: 10.3724/SP.J.1011.2010.00988

Abstract(1623) PDF(1619)

Abstract:
GGE (genotype main effect and genotype-environment interaction) biplot analysis is a method based on principal component analysis (PCA) for the effective exploration of multi-environment trials (METs). It allows visual understanding of genotype-environment interaction (G×E-interaction), cultivar yield stability for each mega-environment, and test-location suitability. Grain yields of 9 spring wheat genotypes (cultivars or lines) tested at 17 national spring wheat regional test sites under rainfed conditions in 2005 were analyzed via GGE biplot and AVONA methods. The results show that G×E-interaction effect is 5.4 times of genotypic effects for grain yield. The stability of different genotypes varies greatly, and genotypes with high yield and yield stability account for only 11% of the total tested genotypes, though some genotypes are specifically adaptable to certain environments. The 17 test-sites are broadly classified into three environments. Accordingly, “8821-1-1” and “longchun 9143” spring wheat are the best genotypes for arid regions of the Loess Plateau, “qingchun193” and “wumai 7” are the best genotypes for arid and cold regions of the Tibetan Plateau, and arid regions of North China, respectively. Based on discrimination ability and environmental representativeness, two ideal test-sites, Yuzhong County of Gansu Province and Huzhu County of Qinghai Province are proposed for spring wheat variety regional test. Grain yield is more closely correlated with precipitation during growing season than the other six environment factors.

Edge effect of trench-pond pattern on rice grain and economic benefit in rice-fish co-culture

WU Xue, XIE Jian, CHEN Xin, CHEN Jian, YANG Xing-Xing, HONG Xiao-Kuo, CHEN Zhi-Jian, CHEN Yu, TANG Jian-Jun

2010, 18(5): 995-999. doi: 10.3724/SP.J.1011.2010.00995

Abstract(1574) PDF(1308)

Abstract:
Rice-fish co-culture has been practiced for over 1 000 years and diverse models have been developed in China. The trench and pond model (which provides shelter for fish during low-irrigation period) may limit rice yield due to reduced rice-stand area. However, strengthened compensation effects from increased edge-zones make up for yield loss in smaller rice-stands. In this study, we conducted a field experiment to estimate the edge effect compensations for lost rice yields induced by trench-pond under different digging patterns. The production of rice and fish were also compared with economic output under different types of trenches. The study shows that average edge effect on first-row grain yield is 52.45%. The average marginal effect of trenches on grain yield is as high as 80%. The compensative effects of the three types of trenches are in the following order: peripheral-trench (95.89%) > cross-trench (85.58%) > straight-trench (58.02%). There is no significant difference between rice and fish yields for the three types of trenches. Economic output for the cross-trench is the highest among the three types of trenches. The results suggest that cross-trench is the best trench pattern for both rice and fish production in rice-fish co-culture.

Evaluating soil salinization risk in typical coastal reclaimed regions in North Jiangsu Province

YAO Rong-Jiang, YANG Jin-Song, CHEN Xiao-Bing, YU Shi-Peng, LI Xiao-Ming

2010, 18(5): 1000-1006. doi: 10.3724/SP.J.1011.2010.01000

Abstract(1729) PDF(1109)

Abstract:
Salinization is a major obstacle for effective exploitation and utilization of soil resources in coastal regions of especially North Jiangsu Province. To that end, the gray relation theory was used to assess the risk of soil salinization in the farmlands of Jinhai Farm, Dafeng County. This is a typical region in North Jiangsu Province with extensive coastal land reclamation. A practical mathematical formula was designed to determine and classify risk evaluation index in the region. Results show that soil salinity, surface soil bulk density and groundwater mineralization are the most important drivers of salinization. For the farmlands of Jinhai, the range of ecological risk value (F) is 0.12~0.60 with an average of 0.30. This indicates that the risk of soil salinization is generally high and varies significantly with location in the study area. The spatial distribution of risk of salinization is similar to the distributions of soil salinity and groundwater mineralization. Due to differences in cropping and cultivation practices, the risk of salinization in rice fields is higher than that in cotton fields. While, there hardly exists low-risk regions, high-risk and medium-risk regions pervade across the study area. Areas of high-risk, medium-risk and severe-risk respectively account for 50.11%, 49.41% and 0.48% of total study area. Areas of high-risk and medium-risk need urgent amelioration measures. The findings in this study provide the basis for quality improvements in moderate-to-low-yield farmlands. It also lays the basis for scientific amelioration and management of saline soils in coastal regions of North Jiangsu Province.

Determination of hydraulic properties of purple soils via one-dimensional horizontal infiltration

CHENG Dong-Bing, ZHANG Ping-Cang, LI Ya-Long, CAI Chong-Fa

2010, 18(5): 1007-1012. doi: 10.3724/SP.J.1011.2010.01007

Abstract(1518) PDF(1124)

Abstract:
he hydraulic properties of three unsaturated purple soils were determined by a simple horizontal infiltration method in one-dimensional horizontal infiltration experiment. While the study accurately estimates soil water retention curve, its estimates of soil water diffusion and conductivity are not very accurate. Estimated soil water diffusion and conductivity of the three purple soils by the simple infiltration method are 1~2 order of magnitude lower than that of the measured values. However, the model-estimated and measured variation tendencies of soil water diffusion and conductivity are similar. Under high soil water conditions, the estimated soil water diffusion and conductivity by the horizontal infiltration method are lower than that of the measured values. However, under low soil water conditions, the estimated soil water diffusion and conductivity by the horizontal infiltration method are higher than that of the measured values. This suggests that the model slowly responds to soil water change.

Analysis of allelochemicals and allelopathic effect of rhizosphere soils of newly planted and ratoon sugarcane (Saccharum officenarum L.)

ZHANG Ai-Jia, YUAN Zhao-Nian, CHEN Dong-Mei, WANG Hai-Bin, WU Wen-Xiang, LIN Sheng, CHEN Ting, CHEN Lan-Lan, FANG Chang-Xun, LIN Wen-Xiong

2010, 18(5): 1013-1017. doi: 10.3724/SP.J.1011.2010.01013

Abstract(1461) PDF(1428)

Abstract:
An experiment was conducted on the allelopathic effects of rhizospheric soil extracts (by water and polarity solvents) from newly planted and ratoon sugarcane (“FN28”, “GZ18”) and non-sugarcane (CK) soils. Putative allelochemicals of the rhizospheric soil extracts were then identified via GC-MS. In comparison with CK, high concentration water extracts inhibit lettuce growth whereas low concentration extracts promote growth. Inhibitory effects of rhizospheric soil water extracts of ratoon sugarcane are higher than that of newly planted sugarcane. Rhizospheric soil extracts from newly planted and ratoon sugarcanes by weak polarity petroleum ether and ether solvents promote lettuce growth. The reverse is true for extracts by medium polarity chloroform and strong polarity methanol. Further allelochemical analysis suggests that inhibitory effect of methanol extract is the strongest. Allelopathic effect of rhizospheric soil of “GZ18” is higher than that of “FN28” both by water extracting and polarity solvent extracting. GC-MS analysis of methanol extract substances from “GZ18” rhizospheric soils shows 54 compounds related with allelopathy, including acids, terpenoids, phenols, steroids and esters.

Identification and fungi toxicity of volatiles in Metasequoia glyptostroboides seeds

YANG Jun-Jie, CHEN Li-Jun, , YANG Hai-Xia, SHI Qing-Feng

2010, 18(5): 1018-1021. doi: 10.3724/SP.J.1011.2010.01018

Abstract(1493) PDF(1523)

Abstract:
GC-MS analysis was used to identify the volatile chemical constituents of M. glyptostroboides seeds, and their toxicity to 8 plant pathogens (Alternaria kikuchiana, A. alternate, Stemphylium botryosum, Botrytis cinerea, Fusarium graminearum, Pestalotiopsis theae, Colletotrichum sp. and A. porri) was measured by mycelium growth inhibition method. The main components of M. glyptostroboides seed volatiles are 1R-alpha-Pinene (46.355%), Limonene (13.663%), Bicyclo [2.2.1] heptan-2-ol,1,7,7 -trimethyl-acetate (1S-endo) (6.941%), Caryophyllene oxide (6.924%), beta-Pinene (4.902%), Bicyclo [3.1.1] heptane,6,6-dimethyl-2-methylene (1S) (4.807%), etc. The volatiles evidently inhibit mycelium growth of 8 plant pathogenic fungi. At 100 μL·dish^-1 dose, the inhibitory rates are higher than 60% to S. botryosum, F. graminearum and P. theae. The results indicate that volatiles of M. glyptostroboides seeds have various active components. They have copious application prospects in medicine, chemical industry and the development of pesticides of agriculture.

Effect of exogenous Gly on the growth and oxidative damage of alfalfa seedling under Cd stress

SUN Hong, LIU He-Gang, CUI Jin-Jin, LIU Xiao-Jing, YANG Li-Lin, XU Jin

2010, 18(5): 1022-1025. doi: 10.3724/SP.J.1011.2010.01022

Abstract(1388) PDF(1360)

Abstract:

Effect of chitosan on germination and enzyme activity of Caragana korshinkii Kom seed from different provenances

ZHANG Jun-Feng, LI Qing-Mei, DUAN Xin-Fang, LIU Guang-Quan, PENG Zuo-Deng

2010, 18(5): 1026-1030. doi: 10.3724/SP.J.1011.2010.01026

Abstract(1456) PDF(1252)

Abstract:
C. korshinkii seeds from two regions (Wuqi County, and Yuyang District in Yulin City) of Shaanxi Province were treated with acidic chitosan solution of different concentrations. Then the germination and seedling growth indices were investigated along with the activities of a-amylase, dehydrogenase, POD and CAT. Results show that chitosan improves seed germination and at the same time shortens germination time. With increasing chitosan concentration, germination indices and enzyme activities initially increase before decreasing under higher chitosan concentration. Seeds from different provenances respond differently to chitosan. When chitosan concentration is 0.5%, germination rate of seeds from Yuyang is 1.2 times that of CK, with mean germination time shortened by 0.9 d. Enzyme activities increase significantly compared with CK, producing the best enhancement effect. At 1.0% chitosan concentration, the germination rate of seeds from Wuqi increases by 13% and the mean germination time shortens by 1.7 d. Enzyme activities increase significantly compared with CK, producing the best enhancement effect. However, 1.5% chitosan concentration inhibits germination of seeds from Yuyang, but does not negatively impact germination of seeds from Wuqi. Chitosan generally improves growth of C. korshinkii seedling. Seedling root length, height, dry-weight, fresh-weight and chlorophyll content significantly increase. Optimum chitosan concentrations for seeds from Wuqi and Yuyang are respectively 1.0% and 0.5%.

Enzymatic hydrolysis of chinaberry bark residue by Penicillium waksmanii F10-2

HAN Li-Rong, WANG Yong-Hong, ZHANG Jing, FENG Jun-Tao, ZHANG Xing

2010, 18(5): 1031-1035. doi: 10.3724/SP.J.1011.2010.01031

Abstract(1345) PDF(1044)

Abstract:
The extra-cellular enzyme activity of Penicillium waksmanii F10-2 was determined using chinaberry bark residues as substrate at different times. The ultra-structure and chemical constituents of the residues before and after fermentation were also compared by using scanning electron microscope (SEM) and Fourier transform infrared spectrum (FTIR). The results show that fermentation of P. waksmanii F10-2 utilizes methyl cellulose as substrate. After 8~16 days of fermentation, the maximum activities of cellulase, hemi-cellulase, lignin peroxidase and Mn-depended peroxidase are 6.42 U·g^-1, 7.62 U·g^-1, 6.55 U·g^-1 and 3.33 U·g^-1, respectively. The ultra-structure of degraded chinaberry bark residues is soft and loose with some micro-pores. FTIR spectrum analysis of the residues shows that P. waksmanii fermentation products degrade components of chinaberry bark residues. After fermentation for 24 d, the ratios of degradation of cellulose, hemi-cellulose and lignin in residues are 42.70%, 33.96% and 24.62%, respectively.

Effect of Trichoderma aureoviride 1010 on chilly stress-resistance of tomato in solar-greenhouse conditions

CHEN Wei-Jing, LI Run-Fang, YANG Huan-Ming, CHEN Jian-Ai

2010, 18(5): 1036-1040. doi: 10.3724/SP.J.1011.2010.01036

Abstract(1298) PDF(1294)

Abstract:
In this study, we determined the enhancement effects of Trichoderma aureoviride 1010 (T1010) on chilly stress-resistance of tomato in solar-greenhouse conditions via soil application and 3 days of inferior chilly-stress (16 ± 2 °C in the day and 8 ± 2 °C at night ). Results show significant differences in the indicators for inferior chilly stress-resistance of functional tomato leaves and roots. SOD, CAT, POD and PPO activities of functional tomato leaves treated with T1010 increase by 266.33%, 16.85%, 20.89% and 632.89% respectively over the control. Carotenoid, ABA, proline, glucose and starch contents also increase by 50.53%, 119.40%, 55.38%, 128.57% and 23.40% respectively. For tomato roots treated with T1010, SOD, CAT, POD and PPO activities increase by 274.10%, 69.06%, 8.26% and 164.14% respectively. The contents of proline, glucose, and starch also increase by 49.81%, 66.00% and 86.76% respectively. In addition to decreasing soluble sugar content, the indicators for functional tomato leaves treated with 1/2T1010 increase at varying degrees. However, the indicators for tomato roots treated with 1/2T1010 decrease at varying degrees. ANOVA analysis shows significant difference in indicators of inferior chilly stress-resistance among CK, T1010 and 1/2T1010 treatments. T1010 positively influences chilly stress-resistance of functional tomato leaves and roots in solar-greenhouse conditions with reasonable soil organic quality.

Effect of root-knot nematode inoculation on rhizospheric soil pH and microbial community of cucumber (Cucumis sativus L. ) plant

XU Hua, RUAN Wei-Bin, GAO Yu-Bao, SONG Xiao-Yan, WEI Yu-Kun

2010, 18(5): 1041-1045. doi: 10.3724/SP.J.1011.2010.01041

Abstract(1929) PDF(1623)

Abstract:
Root-knot nematodes (RKNs) are the most destructive field pathogens of cucumber plant. This study evaluated rhizospheric soil pH and soil microbial community response to RKN inoculation. Results of the study show that aerobic bacteria, anaerobic bacteria and total bacteria number as well as bacteria/fungi (B/F) ratio gradually decline with the increasing inoculation rate. However, fungi number gradually increases with increasing inoculation rate. Both actinomyce/fungi (A/F) ratio and actinomyce number increase at an inoculation rate of 2 000 eggs per plant, but gradually decrease with increasing inoculation rate. Under RNKs inoculation, rhizospheric soil pH is significantly positively correlated with aerobic bacteria, B/F, anaerobic bacteria number, total bacteria number, actinomyce number and A/F ratio. However, rhizospheric soil pH is significantly negatively correlated with fungi number. RKNs infection apparently increases fungal population density in rhizospheric soils, implying degradation of soil quality due to RKNs infection.

Relationship between Oides decempunctata and its natural enemies under different fertilization treatments in grapery in Jianghuai hilly region and ancient course of the Yellow River

LI Gui-Ting, TIAN Yu-Long, ZOU Yun-Ding, LU Shen, DANG Feng-Hua, KE Sheng-Bing, ZHAO Xue-Juan, YU Kun

2010, 18(5): 1046-1053. doi: 10.3724/SP.J.1011.2010.01046

Abstract(1402) PDF(1192)

Abstract:
A systematic investigation of O. decempunctata and its natural enemies was conducted in grapery under four fertilization treatments (water, vinegar, neodymium and lanthanum spray) in order to protect and use natural enemies in integrated pest management and high-yield cultivation of graperies in Xiaoxian County and Feidong County, Anhui Province. Grey systematic and ecological niche analyses were used to establish the number and spatio-temporal distribution correlations between O. decempunctata and its natural enemies. The results of synthetic ranking are that, for Xiaoxian grapery, the main natural enemies of O. decempunctata are Propylaea japonica, Erigonidium graminicolum and Lycosa pseudoannulata under water spray treatment; L. pseudoannulata, P. japonica and Harmonia axyridis under vinegar spray treatment; E. graminicolum, H. axyridis and P. japonica under neodymium spray treatment; and P. japonica, H. axyridis and E. graminicolum under lanthanum spray treatment. For Feidong grapery, the main natural enemies of O. decempunctata are E. graminicolum, Theridion octomaculatum and L. pseudoannulata under water spary treatment; L. pseudoannulata, E. graminicolum and P. japonica under vinegar spray treatment; E. graminicolum, L. pseudoannulata and T. octomaculatum under neodymium treatment; and T. octomaculatum, E. graminicolum and L. pseudoannulata under lanthanum spray treatment. Natural enemies of O. decempunctata distinctly vary with treatment type and location. The most common natural enemies of O. decempunctata in two locations are E. graminicolum and L. pseudoannulata under water spray treatment, L. pseudoannulata and P. japonica under vinegar spray treatment, and E. graminicolum under neodymium and lanthanum spray treatments.

Pymetrozine application techniques against Nilapabata lugens (St?l) and safety evaluation to its natural enemies

XU De-Jin, GU Zhong-Yan, XU Guang-Chun, XU Xiao-Long, FAN Peng

2010, 18(5): 1054-1059. doi: 10.3724/SP.J.1011.2010.01054

Abstract(1497) PDF(1523)

Abstract:
Laboratory bioassay, pot and field experiments on the action mode, toxicity to instar, application technique and control effect of pymetrozine against brown planthopper (BPH) [Nilapabata lugens (St?l)] were conducted. The impact of pymetrozine on N. lugens natural enemies, Cyrtorhinus lividipennis (Reuter) and spider [Agelena difficilis (Fox)], was investigated. The results show that pymetrozine influences BPH through not only contact poisoning, but also a strong systemic action. LC50 values after 168 h of pymetozine application against the 1st and 3rd BPH nymphs are respectively 14.99 mg·L^-1 and 13.08 mg·L^-1, significantly lower than those against the 5th and adult nymphs. The results from the pot experiment indicate that control effects of pymetrozine are high when pots contain water layer. After 15 days, control effects exceed 95% in young BPH larva under 25% pymetrozine WP at 300 g·hm^-2, 450 g·hm^-2 and 600 g·hm^-2 with sustained paddy water layer. Further studies show that pymetrozine is moderately toxic to C. lividipennis (Ⅲ class), and C. lividipennis number decreases after pymetrozine application. Pymetrozine is safe to spiders (Ⅰ class), with insignificant impact on spider population after spray. This study therefore lays the scientific basis for rational use of pymetrozine.

Estimation of annual total livestock/poultry excrement in Henan Province

ZHOU Kai, LEI Ze-Yong, WANG Zhi-Fang, SHI Jie, PENG Xing-Zhi

2010, 18(5): 1060-1065. doi: 10.3724/SP.J.1011.2010.01060

Abstract(2429) PDF(2110)

Abstract:
Based on statistical data and various related parameters, annual total excrement from main livestock/poultry in Henan Province was evaluated for 2008. The study shows that gross livestock/poultry excrement in 2008 comprises of 18 329.5×10⁴ tons of feces and 9 790.8×10⁴ tons of urine. The total livestock/poultry excrement contains 169.84×10⁴ tons N, 96.33×10⁴ tons P, and 142.93×10⁴ tons K. Among the main livestock/poultry (e.g., pig, cattle, sheep, rabbit and chicken), pigs excrete the highest amount of feces, accounting for 39.5% of the total excrement. This is followed by cattle, accounting for 27.0% of the total excrement. 83.4% of the livestock/poultry urine is also produced by pigs, followed by cattle (11.6%). The highest amount of livestock/poultry excrement comes from Zhumadian City, followed by Nanyang City, Zhoukou City, Shangqiu City and Kaifeng City. Excrement from these five cities accounts for almost half of total livestock/poultry excrement in Henan Province. Average excretion load of croplands is 40.79 t·hm^-2, which is much higher than the 4.19 t·hm^-2 national average. This finding suggests that rural environments of Henan Province are confronted with severe pollution and ecological risks.

Using Equivalent Standard Pollution method to evaluate impacts of agricultural non-point pollution resources on water environment in Shandong Province

GAO Xin-Hao, JIANG Li-Hua, LI Xiao-Lin, LIU Zhao-Hui, XU Yu, WEI Jian-Lin

2010, 18(5): 1066-1070. doi: 10.3724/SP.J.1011.2010.01066

Abstract(1386) PDF(1165)

Abstract:
A comprehensive evaluation of impacts of different pollution resources on water environment is a prerequisite for controlling total amount of pollutants. This forms an important basis for prevention of agricultural non-point source pollution. The amount of total nitrogen and phosphorus loss from agricultural sources (chemical fertilizer, livestock and poultry manure, and live sewage), equivalent standard pollution loads (ESPL) and equivalent standard pollution indices (ESPI) of 17 cities in Shandong Province were calculated in this study. The results show that chemical fertilizer and livestock and poultry manure are the biggest sources of total nitrogen and phosphorus, respectively. Livestock and poultry manure, chemical fertilizer and live sewage account for 49.3%, 42.6% and 8.1% of the total nutrients loss respectively. Total ESPL of nitrogen is slightly higher than total ESPL of phosphorus in Shandong Province. Of the investigated cities, Weifang has the highest ESPLs of chemical fertilizer, livestock and poultry manure, as well as nitrogen and phosphorus. Linyi exhibits the highest ESPL of live sewage. Livestock and poultry manure has the strongest impact on water environment in Shandong Province. ESPL ratio for live sewage, chemical fertilizer and livestock and poultry manure is 1∶4∶7. Based on comprehensive ESPL effect and water resources, Dezhou has the highest ESPI and potential threat to water environment in Shandong Province. This is followed by Liaocheng, Heze, Binzhou, and Tai’an. In order to reduce water pollution, it is important to implement different prevention and control strategies based on key pollution sources in different regions.

Relationship between topographic factor and land use—A case study of Zhuanyaogou watershed

HAN Jian-Ping, JIA Ning-Feng

2010, 18(5): 1071-1075. doi: 10.3724/SP.J.1011.2010.01071

Abstract(1600) PDF(1642)

Abstract:
GIS and SPSS were used to quantitatively analyze the relationships between land use type and topographic factors for 2003 and 2008. The succession pattern and driving factors of land use were also explored on 10 m×10 m grid-base for Zhuanyaogou watershed in the hilly region of the Loess Plateau of China. The study shows that land elevation, slope gradient and aspect significantly influence the spatial distribution of land use. The average elevation, slope gradient and aspect of the watershed are respectively 1 069 m, 19.24° and 279° (west). Aspect-distribution map from average sin(aspect) and cos(aspect) of different land use types clearly shows the distribution characteristics of land use. Farmlands and barren-hills form about 80% of the study area, and their distribution change controls the topographic pattern of land use distribution in the watershed. Farmlands are mainly located in the upper slope and tops of the loess mountain ridges with low slope gradients and high elevations. While farmland area is significantly negative correlated with slope gradient, it is significantly positive correlated with elevation. Barren hills exhibit the opposite trend. The results fully reflect the topographic characteristics of land use in the study area. Implementation of eco-construction projects could induce significant changes in the spatial distribution of land use in the short-run.

Effect of changing spatial grain size and land-use classification on landscape index — A case study of Wenxi County, Shanxi Province

GAO Yan, BI Ru-Tian, CAO Yi

2010, 18(5): 1076-1080. doi: 10.3724/SP.J.1011.2010.01076

Abstract(1321) PDF(1302)

Abstract:
Using the 1∶10 000 land-use map of Wenxi County of Shanxi Province, GIS and the landscape pattern software Fragstats, the effect of spatial grain size on landscape indices of different land-use classification systems, and the effect of land-use classification system on the landscape indices under different spatial grain sizes were investigated. The results show that with increasing spatial grain size, patch density (PD), landscape shape index (LSI) and landscape contagion (CONTAG) gradually decline, whereas perimeter-area fractal dimensions (PAFRAC) increase. There is no significant change in the largest patch index (LPI) and Shannon diversity index (SHDI). With increasing number of land-use types, PD, LSI and SHDI increase, and LPI decreases. There is no significant change in PAFRAC, and the landscape contagion curve changes rather complicated.

Application of traditional ecological footprint and its derivatives in evaluating utilization of croplands

WANG Guo-Gang, YANG De-Gang, SU Rui, TANG Hong

2010, 18(5): 1081-1086. doi: 10.3724/SP.J.1011.2010.01081

Abstract(1311) PDF(1173)

Abstract:
Cropland is a public resource with important functions such as ensuring food security, offsetting the demands of industrialization and urbanization and balancing ecological requirements by returning farmlands to forests and grasslands. Based on emergy theory analysis, two modified ecological footprint accounting models [regional emergetic ecological footprint (REMF) and cropland emergetic ecological footprint (EMEF)] and the traditional ecological footprint model were used to evaluate utilization of croplands in Xinjiang. The merits and demerits of the three models were also determined. The study shows rising ecological footprint of cropland for per-capita in Xinjiang in 1978~2007. Per-capita ecological capacity in the study area is stable, indicating a marked decline in sustainable ecological development index (ESI) in the region. EMEF also shows an unsustainable use of croplands in Xinjiang for 2001~2007, following a sustainable use in 1978~2000, with ESI dropping from 5.63 in 1978 to 0.60 in 2007. Comparative studies of the three methods show that the regional emergy ecological footprint model (which is only a general analysis of regional sustainability) is not suitable for evaluating use of croplands. Cropland emergy ecological footprint model is the best as it takes into account of sustainability of croplands and to some extent overcomes the shortcomings of traditional ecological footprint model.

Constructure of competitiveness evaluation index system of ecological agriculture using AHP method

ZHENG Jun, SHI Jian-Min

2010, 18(5): 1087-1092. doi: 10.3724/SP.J.1011.2010.01087

Abstract(1840) PDF(1146)

Abstract:
Whether eco-agriculture will be a dominant strategy and basic agricultural and rural economic development pattern in China depends on its competitive advantage over other agro-development models. Using the AHP method (which is driven by “elements-structure-performance” paradigm), the competitiveness evaluation index system of eco-agriculture was established, which was composed of 5 first-level indexes, 22 second-level indexes and 66 third-level indexes. The results show that the body layer is the main impact zone in 5 first-level indexes. This is followed by the efficiency layer, product layer, element layer and organization layer. Based on the results, appropriate countermeasures for building and enhancing the competitiveness of eco-agriculture are advanced.

Research on eco-economic functional regionalization of important water supply region of the Yellow River in Gannan area

XUE Zhong-Zheng, LI Wen-Long, XU Dan-Dan, WANG Xun, YANG Zhan-Shan

2010, 18(5): 1093-1098. doi: 10.3724/SP.J.1011.2010.01093

Abstract(1614) PDF(1076)

Abstract:
Using TM image and statistical yearbook data of the Yellow River source in Gannan area, Gansu Province, along with vegetation coverage, water conservation, land use pattern, population density and agricultural and animal products as ecological factors, the eco-economic functional regionalization of important water supply region of the Yellow River in Gannan was conducted. An analytical hierarchy process was developed to weigh ecological factors in study area. Based on the weights of the ecological factors, the Yellow River source region in Gannan was classified into town construction and eco-agricultural economy zone, hydro-ecological recharge zone of the Yellow River, eco-agricultural economy zone of the Tao River, livestock product supply and ecological tourism zone, and livestock product supply zone of Maqu. The ecological characteristics and problems in eco-economic development of different zones were discussed through analysis on the internal connection among different zones. The developmental directions, ways and countermeasures were also advanced. The findings of the research could provide guidelines for protecting, constructing and developing the study area.

Factors affecting farmers’ willingness to adopt wheat/maize agronomic water-saving technology in the piedmont plain region of Mount Taihang

LIU Xiao-Min, WANG Hui-Jun, LI Yun-Chao

2010, 18(5): 1099-1105. doi: 10.3724/SP.J.1011.2010.01099

Abstract(1568) PDF(1341)

Abstract:
Farmers is the main body of agricultural water-saving. For successful adoption of agronomic water-saving technologies, it is important to learn the factors affecting farmers’ willingness to adopt agricultural water-saving technologies. This paper therefore analyzed the factors affecting farmers’ willingness to adopt wheat/maize agronomic water-saving technologies in the piedmont plain of Mount Taihang using farmer household investigation and Logit model. The study shows that the proportion of crop to gross income of farming households, cost of water, and training significantly positively affect farmers’ willingness. However, the degree of water shortage has a significant negative effect on farmers’ willingness. In the piedmont plain of Mount Taihang, wheat/maize agronomic water-saving technologies should be introduced to households with high proportion of crop to gross household income, high proportion of labor to household population, high annual gross household income, large farmland area, female householder and a householder with high level education. As farmers’ awareness of water-saving is generally weak in the study area, it is necessary to use additional means to promote water-saving technologies to farmers. In order to popularize wheat/maize agronomic water-saving technologies in the piedmont plains of Mount Taihang, demonstration households and the effects of leading households should be emphasized. Government support should also increase, while more effort, such as training, is needed to spread information about agronomic water-saving in the region.

Circular agriculture as an important way to low-carbon economy

GAO Wang-Sheng, CHEN Yuan-Quan, DONG Wen

2010, 18(5): 1106-1109. doi: 10.3724/SP.J.1011.2010.01106

Abstract(2218) PDF(2045)

Abstract:
Low-carbon economy is a new developing economic thinking that responds to global climate change. In this paper, energy saving and emission reduction in agriculture is presented as an important low-carbon agriculture development method. This is mainly achieved through circular agriculture development. The ways of circular agriculture development in China includes enhancement of cropland carbon pools and cropland input reduction via developing circular production patterns. It is also an important way to develop combined circular pattern of cropping and pasture for reducing pollution from wastes and improving the competitive strength of pasture. Extending production chains in croplands and increasing farmer income via improving circular chains of edible fungi also make it viable. Meantime, a well developed circular agriculture increases biodiversity, improves the use efficiency of natural resources, enhances engineered energy saving and emission reduction. Developing circular industrial patterns and agricultural enterprises is another important way.

Countermeasures of low-carbon economy for sustainable development of China’s tea industry

HUANG Dong-Feng, LI Wei-Hua, FAN Ping, QIU Xiao-Xuan

2010, 18(5): 1110-1115. doi: 10.3724/SP.J.1011.2010.01110

Abstract(1615) PDF(1663)

Abstract:
The indispensable connotation and development of low-carbon economy were introduced in this paper. Moreover, the major limiting factors of tea-oriented industry development in China’s low carbon economy were analyzed. These factors include blindfolded and excessive use of nitrogenous fertilizers, high costs and frequent use of pesticides, difficulties in timely tea shoot picking, low use efficiency of tea resources, low input/output proportion, low benefits due to the large acreages of low-yield tea gardens, low efficiency of matter and energy cycles due to single species and short bio-chain tea gardens, etc. Finally, countermeasures for the sustainable development of China’s tea-oriented industries in low-carbon economy are put forward. Such countermeasures include reducing nitrogenous fertilizer use, and in-depth studies of fertilizer application techniques to increase use efficiency, reducing application rate and improving efficiency of pesticides, integrating agronomic measures with prevention/cure of plant diseases and pests, optimizing structural varieties and accelerating low-output tea garden rebuilding, promoting high efficiency matter and energy cycles of tea gardens via eco-tea garden construction and bio-chain extension.

Effect of elevated CO₂ concentration and increased temperature on physiology and production of crops

FANG Shi-Bo, SHEN Bin, TAN Kai-Yan, GAO Xi-Ning

2010, 18(5): 1116-1124. doi: 10.3724/SP.J.1011.2010.01116

Abstract(1817) PDF(3146)

Abstract:
Increasing concentration of global atmospheric CO₂ and temperature are the two most important factors in the national list of the impact of climate change on crop yield. This brief summary focused on research advances on the impact of increasing [CO₂] and temperature on crop photosynthesis, respiration, transpiration, yield, quality, etc. The review shows that increasing [CO₂] increases the rates of photosynthesis and transpiration, but decreases respiration rate and stomatal conductance. Though crop quality decreases with increasing yield, there is no general research consensus on this trend. C3 and C4 crops’ response to variations in CO₂ concentration is inconsistent, with short- and long-term effects on photosynthetic pathways. It is generally conceived that atmospheric temperature increase inhibits crop photosynthesis, reducing crop yield. Most of the existing reports on the response of crop yield to climate change focus on crop modeling or simulation experiment. Research also shows discrepant model/simulation results. There are also discrepant yield assessment results from different scholars. Some recent studies suggest that rising temperatures have a nonlinear effect on crop yield. Crop yield declines rapidly when temperatures exceed threshold values. As most of the simulation experiments are conducted in gas chambers (which are quite different from real-world conditions), their conclusions require further validation. The crop model results generally lack verifications by experiment.

Research trend on regulating effect of laser pretreatment on plant growth

CUI Ying, CHEN Yi-Ping

2010, 18(5): 1125-1129. doi: 10.3724/SP.J.1011.2010.01125

Abstract(1803) PDF(1649)

Abstract:
This paper reviewed researches in recent years on the response of plant growth, physio-biochemistry to laser treatment. The review shows a clear research trend. Earlier studies focused on the effects of laser pretreatment on seeds germination, seedlings growth and physio-biochemical characteristics, with emphasis on the mechanisms by which laser pretreatment influences plants. Latter studies, on the other hand, focused on the effects of laser pretreatment on physio-biochemical traits of plants under such environmental stresses as drought, cold and enhanced UV-B radiation. In the latter research stage, more emphasis was placed on the effects of laser pretreatment under enhanced UV-B radiation on plants. Research results indicated that laser irradiance improved plant resistance to drought and cold stress, and enhanced UV-B radiation. On these bases, the mechanisms were discussed also. Future research should focus on repairing mechanisms of laser-pretreated plants under global eco-environmental change conditions.

Research advances of phenolic functional mechanisms in soils and plants

LIN Kai-Min, YE Fa-Mao, LIN Yan, LI Qing-San

2010, 18(5): 1130-1137. doi: 10.3724/SP.J.1011.2010.01130

Abstract(2233) PDF(4163)

Abstract:
Phenol is an important element of secondary metabolism. It affects plant growth, nutrient absorption, physiological characteristics, enzyme activity, soil and micro-organism in growth environment, etc. This paper describes phenolic functional mechanisms in soils and plants. The content and distribution of phenol in plant ecosystem, its effect on physiological and biochemical characteristics of plants, and on physical and chemical properties of soils were discussed too. The paper prospects the research trend of phenolic substances in practical agriculture and forestry to provide the basis for solving phenol-related production decline in agriculture and forestry.

Participatory geographic information system review

WANG Xiao-Jun

2010, 18(5): 1138-1144. doi: 10.3724/SP.J.1011.2010.01138

Abstract(2713) PDF(4678)

Abstract:
Participatory Geographic Information System (PGIS or PPGIS) is the spontaneous linkage of participatory concepts and approaches with Geographic Information Techniques and System (GIT&S). In the last two decades, it was both a technology and a tool for assisting communities and the public to organize scientific and indigenous spatial knowledge systems by using GIT&S. It was also a planning support system (PSS) for effective participatory planning and decision-making at community, regional levels. Based on the reviewed references and authors’ perspectives of PGIS, this paper comprehensively introduces the technical and social backgrounds of PGIS. In the context of participation, the paper also identifies the main features of PGIS (after screening the merits against the demerits of traditional GIS). The paper further evaluates the global application patterns of PGIS under participatory programs and conditions. The paper specifically notes web-based PPGIS, community-integrated GIS, visual-interactive PGIS and GIS for participation. The review shows that PGIS is still in its infancy and requires in-depth research on the technical, social and political issues of participation.

Effect of cadmium and acid rain dualcross-stress on membrane lipid peroxidation in germinated soybean seeds

WU Peng, ZHOU Qing

2010, 18(5): 1145-1147. doi: 10.3724/SP.J.1011.2010.01145

Abstract(1590) PDF(1266)

Abstract:

Herbicidal activities of Paeonia lactiflora Pall. organs

LUO Xiao-Yong

2010, 18(5): 1148-1150. doi: 10.3724/SP.J.1011.2010.01148

Abstract(1071) PDF(1072)

Abstract:

2010 Vol. 18, No. 5