中国生态农业学报(中英文)

Effect of tillage practices on structural properties and content of organic carbon in tilth soil

XU Shu-Qing, ZHANG Ren-Zhi, DONG Bo, Zhang Ming

2009, 17(2): 203-208. doi: 10.3724/SP.J.1011.2009.00203

Abstract(1954) PDF(2047)

Abstract:
To further explore tillage practices for improving soil structure, the effect of different tillage practices on the structure and organic carbon of tilth soils were investigated using routine method (Wet-sieving, Potassium dichromate volumetry and Core-cutting sampling). The 7-year research was conducted at an experimental station in the semiarid Loess Plateau zone in central Gansu Province. The conservative management practices of no-tillage (NT), conventional tillage with straw incorporation (TS) and no-tillage with straw mulch (NTS) increase soil organic C and water-stable soil aggregates contents, with the highest effect under NTS tillage. Soil bulk density decreases while soil porosity increases, greatly improving soil structure under NTS in the 0~10 cm soil layer. Content of soil water-stable aggregate (1~0.5 mm) is the highest in all 3 soil layers, 0~5 cm, 5~10 cm and 10~30 cm. Soil water-stable aggregate (>0.25 mm) has a significant positive correlation with soil organic C content and porosity, but is significantly negatively correlated with soil bulk density.

Effect of different crop rotation systems and continuous fallow on soil microbial biomass carbon and nitrogen under different fertilizer treatments

LIANG Bin, ZHOU Jian-Bin, 1YANG Xue-Yun, AI Na

2009, 17(2): 209-214. doi: 10.3724/SP.J.1011.2009.00209

Abstract(1688) PDF(1295)

Abstract:
Crop rotation affects the amount and quality of crop residue returned into the soil. In this study, a 17-year long-term field experiment was conducted to study the effect of different crop rotation systems [continuous fallow(CF), wheat and summer fallow (WF), and wheat and maize rotation (WM)] under various fertilization treatments on the contents of soil microbial biomass carbon (SMBC), soil microbial biomass nitrogen (SMBN), soluble organic carbon (SOC) and soluble organic nitrogen (SON). Compared with WF rotation, WM rotation increases SMBC, SMBN, SOC, SON, total organic carbon (TOC) and total nitrogen (TN) contents in the 0~10 cm layer soil, but this is not so obvious in the 10~20 cm soil layer. CF also significantly increases SMBC, SMBN, SOC, SON, TOC and TN contents in the 0~10 cm soil layer in comparison with treatments without fertilizer (CK) or with chemical fertilizer (NPK) under both WF and WM rotations. The effect of different fertilizer treatments on the level of SMBC, SMBN, SOC and SON is in the following order: MNPK>NPK>CK. Crop rotation systems and fertilizer treatments have insignificant effect on SMBC/TOC and SMBN/TN ratios in the soil.

Effect of land-use type on enzyme activity in black soil

HOU Xue-Ying, HAN Xiao-Zeng, WANG Shu-Qi, SONG Chun, ZHANG Di

2009, 17(2): 215-219. doi: 10.3724/SP.J.1011.2009.00215

Abstract(1461) PDF(1233)

Abstract:
Based on long-term experiment at Hailun Agricultural Ecology Station of Chinese Academy of Sciences, the characteristics of soil enzyme activity in black soil under different land-use types were investigated. The results show significant differences among the soil enzyme activity under different land-use types. In comparison with bare-land (BL), urease, invertase and phosphatase activity in grassland (GL) respectively increases by 24.66%, 29.56% and 34.67% in April, and 56.12%, 128.40% and 30.42% in July. This suggests that after natural restoration, soil bioactivity increases and soil fertility improves significantly. Compared, however, with the control (i.e. zero-fertilizer; ZF), soil enzyme activity in the cropping treatments follow the same order: nitrogen and phosphorus fertilizers plus organic manure (NPM) > nitrogen and phosphorus fertilizers (NP) > zero-fertilizer (ZF) application. Invertase and phosphatase activity in the ecosystems have the following order: GL > cropping system > BL, and urease activity is the order of: NPM treatment in cropping system > GL > NP treatment in cropping system > ZF treatment in cropping system > BL. This indicates that some fertilization patterns and natural restoration increase soil enzyme activity thereby improving soil fertility. Urease, invertase and phosphatase activity is significantly positively correlated with soil organic matter and total N content, largely reflecting soil property.

Response of typical paddy soil fertility to long-term cultivation in Taihu Lake Region

WANG Xu-Kui, XU Mao, WANG Ji-Dong, WANG Jian-Ming, ZHANG Yong-Chun

2009, 17(2): 220-224. doi: 10.3724/SP.J.1011.2009.00220

Abstract(1600) PDF(1269)

Abstract:
The chemical properties of collected soil samples (2004) were compared with that of the Second National Soil Survey (1982) to analyze changes in soil fertility in Wujin, Taihu Lake Region of Jiangsu Province. The results show that of all the six sub-soil varieties of paddy soil collected from 198 sampling sites, the average content of soil total nitrogen, organic matter, available phosphorous and potassium has significantly increased from 1982 to 2004. That of soil pH and CEC (cation exchange capacity) has decreased during the same period. The soil fertility indices of the six paddy sub-soil varieties are largely the same, except for silty and sandy soils. A single factor soil fertility index for all the sub-soil varieties have a similar trend, i.e. available potassium and pH are the lowest single factor soil fertility indices for 1982 and 2004 respectively. White soil has the lowest pH fertility index (1.73). CEC fertility index has decreased from 2.91 ~ 3.0 of the Second National Soil Survey to 2.14 ~ 2.93 of 2004 collected samples. This indicates that the major restricting factor for soil fertility in this region is low soil pH and loss of exchangeable base anions.

Soil nitrogen status in Tieguanyin tea plantation of Fujian Province

ZHENG Li-Yan, HOU Ling-Li, CHEN Yan-Hui, GUO Ya-Ling, ZHUO Jing-Jing, WANG Guo

2009, 17(2): 225-229. doi: 10.3724/SP.J.1011.2009.00225

Abstract(1795) PDF(1092)

Abstract:
An investigation on the content and availability of nitrogen in surface soil and corresponding nitrogen concentration in tea leaf was conducted in 14 major Tieguanyin tea-producing areas in Anxi, Yongchun and Hua’an Counties of Fujian Province. The objective of the research was to determine N supply capacity of soil of Tieguanyin tea plantation in Fujian Province. To that end, 150 surface soil samples and corresponding tea leaves were collected and analyzed. The results show that total soil N is medium to low with an average of 0.79 g·kg^-1. Alkali-hydrolysis N is medium to high with an average of 95.56 mg·kg^-1. Total soil N is significantly correlated with alkali-hydrolysis N. Organic matter content and CEC have significant correlations with both total and alkali-hydrolysis N. Total soil N content also depends on the parent soil, and decreases in the following order: paddy rice soil > yellow soil > red soil > yellowish red soil > lateritic red soil. Soil with higher clay content contains higher total N. N concentration in tea leaf ranges from 8.1~141.8 g·kg^-1, with an average of 23.7 g·kg^-1. No significant correlation exists between tea-leaf N and soil alkali-hydrolysis N. The use of alkali-hydrolysis N as a source of soil nitrogen and tea-leaf N concentration index to monitor N deficiency in tea plants is subject to further research. More organic manure is required for the tea plantations in Fujian Province. It is important to avoid over application of N fertilizer.

Tropical Crop Genetics Resources Institute, Chinese Academy of Tropical Agricultural Science; Key Open Lab of Tropical Crop Idioplasm Resources, Ministry of Agriculture, Danzhou 571737, China

HAO Li-Hong, ZHANG Dong-Ming, , WU Peng-Fei, DAI Yu, QI Zhi-Ping

2009, 17(2): 230-234. doi: 10.3724/SP.J.1011.2009.00230

Abstract(1597) PDF(1509)

Abstract:
Geographical information system (GIS) combined with Geostatistics was applied to determine the spatial distribution of heavy metal (Hg, Cd, Pb, As and Cr) contents in the farmlands of Hainan Island. The results show that average content of the five heavy metals is below Grade Ⅱ standard of the National Environmental Quality Standard for Soil (GB15618-1995). Theoretical semivariogram models of soil Hg, Cd, Cr and Pb match well with exponential models. Spatial correlation of Hg and Pb is weak, indicating that their content is largely affected by soil formation factors. Theoretical semivariogram model of soil As matches well with the Gaussian model. The distributed spatial correlation of Cd, Cr and As is moderate, indicating that their content is affected by external inputs. Distribution contour maps of the 5 heavy metals for farmlands in Hainan Island obtained from Kriging in GIS show that heavy metal pollution caused by external inputs from industrial zones are most serious on Hainan Island.

Effects of different organic fertilizers on soil microbial biomass and yield of peanut

LIN Xin-Jian, WANG Fei, CAI Hai-Song, LIN Rong-Bin, HE Chun-Mei, LI Qing-Hua, LI Yu

2009, 17(2): 235-238. doi: 10.3724/SP.J.1011.2009.00235

Abstract(1558) PDF(1637)

Abstract:
A pot experiment was set up to investigate the effects of different organic fertilizers on soil microbial biomass and yield of peanut. The results show that economic and biologic yields of peanut are improved by applying fertilizers. The highest yields are for the treatment with compound organic fertilizer containing monosodium glutamate. The total amount of bacteria, epiphyte and actinomyce of soil in the treatment with chicken faeces is highest among the different fertilizer treatments, while the other treatments have only minor differences. Through total DNA extraction, PCR amplification and DGGE analysis of soil microbe, it is found that the certain microbe population increases by the application of various organic fertilizers compared with the treatments of inorganic fertilizer and CK. Also the application of different organic fertilizers improves microbial biomass though to different degrees. Therefore different organic fertilizers affect both soil microbial biomass and diversity trait.

Effect of slope and planting mode on erosion and nutrient loss in purple soils

ZHOU Jing, HE Bing-Hui, LIU Li-Zhi, HE Dan

2009, 17(2): 239-243. doi: 10.3724/SP.J.1011.2009.00239

Abstract(1535) PDF(1026)

Abstract:
Based on the six runoff plots built at the soil and water conservation monitoring station in Fuling, the soil and water loss on cultivated purple soil slopes was investigated. The results show that plot runoff and sedimentation increase with increasing rainfall. Environmental rehabilitation reduces soil and water loss with only 0.41 kg·m^-3 sediment from 3.66 m³ runoff, an effective control measure of soil and water loss on cultivated purple soil slopes. On cultivated plots which in sequence with slope, evident positive correlations exist between runoff and rainfall, but with less evident correlation between sediment and rainfall. Runoff and sediment decreases with decreasing slope degree. 15° slope plough is most environmental friendly, but as to whether it is most suitable for cultivation in Fuling area is subject to further rainfall data analysis. In one strong rainfall observation, the sequence of soil nutrient loss is almost consistent with runoff and sediment. Runoff and sediment on monitoring plots with waste residue of building material are much higher than on other plots, indicating it is important to prevent soil and water loss on soil-water -conservation engineering.

Effect of non-tillage with straw mulch on wind erosion in irrigated oases of Hexi Corridor

ZHANG Wen-Ying, ZHANG En-He, JING Rui, HUANG Gao-Bao

2009, 17(2): 244-249. doi: 10.3724/SP.J.1011.2009.00244

Abstract(1375) PDF(1085)

Abstract:
A wind tunnel simulation experiment was performed to quantitatively determine soil wind erosion and wind profile in the 25 ~ 250 mm soil layer under two stubble heights (20 cm and 40 cm) and two stubble modes (stubble with stem and overpowered stubble after harvest). The relationship between soil erosion rate and wind velocity was analyzed. The results show that NS (no-tillage with high stubble at spring wheat harvest) treatment under wind velocity below 20 m·s^-1 significantly reduces soil wind erosion (P < 0.05). Compared with conventional tillage and NPS40 (leaving 40 cm stubble at spring wheat harvest), wind speed of NS40 (no-tillage with 40 cm stubble at spring wheat harvest) treatment decreases by 87.84% and 5.89%, respectively. This indicates that NS40 not only has the lowest wind erosion but the best effect on preventing wind erosion. A power function relation exists between wind erosion rate (Q）and wind velocity (V) under conventional tillage, while a quadratic function relation exists between Q and V under no-tillage treatment.

Soil seed bank under different diversity restoration measure in the grassland of Bashang region

LIU Jian-Li, WANG Yan-Hui, CHENG Li-Li, MA Chang-Ming, YUAN Yu-Xin

2009, 17(2): 250-255. doi: 10.3724/SP.J.1011.2009.00250

Abstract(1485) PDF(1106)

Abstract:
Field surveys and laboratory experiments were conducted to study the characteristics of soil seed banks such as species composition, density and diversity in Bashang grasslands. Results show that soil seed bank richness under shallow plough treatment (18) is greater than that under nature restoration (15) and that under nature restoration is in turn greater than that under deep plough treatment (14). Soil seed bank density under nature restoration, shallow and deep plough treatments, is respectively 23 949, 15 746 and 10 600 seed·m^-2. Soil seed bank density under shallow and deep plough treatments respectively decreases by 34.3% and 55.7% than under nature restoration. Regression analysis indicates that the relationship between density of soil seed bank and that of associated vegetation has a cubic-shaped curve. There is high similarity of soil seed bank among diversity restoration measures. However, the similarity decreases with increasing artificial disturbance.

Soil moisture dynamics of different land-cover types in the black soil regions of China

WANG Feng, WANG Shu-Qi, HAN Xiao-Zeng, WANG Feng-Xian, ZHANG Ke-Qiang

2009, 17(2): 256-260. doi: 10.3724/SP.J.1011.2009.00256

Abstract(1545) PDF(1399)

Abstract:
Based on collected soil moisture data from the fixed-position monitoring system in the black soil regions of China, soil moisture dynamics in different land-cover types were analyzed. The results show that the variation in soil water under the three land-cover types decreases with increasing soil depth for which vertical change in soil water along the soil profile can be put into four groups, vertiginous layer, active layer, transitional layer and relative stable layer. The depth of soil water cycle for the different land-cover types is as follows: soybean-land > grassland > bare-land, and the order of soil water cycle intensity is: grassland > soybean-land > bare-land. Soil water content in the three land-cover types increases with increasing soil depth, and water content of the surface layer (0~20 cm)in bare-lands is higher than in grasslands and soybean-lands. However, under 30 cm soil depth, soil water content takes the following order: grassland > bare-land > soybean-land. Water storage in the 170 cm soil layer is controlled by rainfall. Under the three land-cover types, the order of total evapotranspiration is: grassland > soybean-land > bare-land.

Water-saving and high-yield mechanism of tomato under different irrigation methods

WANG Yan, CAI Huan-Jie, CHEN Xin-Ming, ZHENG Jian, JI Hong

2009, 17(2): 261-265. doi: 10.3724/SP.J.1011.2009.00261

Abstract(1531) PDF(1190)

Abstract:
The objective of this article was to study the effect of different irrigation methods (non-pressure subsurface irrigation, drip irrigation and furrow irrigation) on photosynthetic physiology, yield, water use efficiency and root hydraulic conductance of tomato. The results show higher root hydraulic conductance of tomato under non-pressure subsurface irrigation (characterized as less water for many irrigation times) than under drip and furrow irrigations. Non-pressure subsurface irrigation adjusts root-zone soil moisture to a suitable range for crop growth which improves crop water absorption capacity. Compared to furrow irrigation, non-pressure subsurface and drip irrigations respectively increase tomato chlorophyll content by 16.2% and 12.8%, reduces stomatal conductance and transpiration dehydration, maintain relatively stable photosynthetic rate and increase WUE by 51.3% and 17.2%. A comprehensive evluation of investment and output indicates that non-pressure subsurface irrigation has the highest benefits, followed by drip irrigation while furrow irrigation is the lowest.

Energy balance and water use efficiency at wheat canopy under free-air CO₂ enrichment

WANG Ming-Na, SUN Yan-Kun, LUO Wei-Hong, ZHU JianGuo, WANG Liang

2009, 17(2): 266-272. doi: 10.3724/SP.J.1011.2009.00266

Abstract(1313) PDF(1282)

Abstract:
FACE system was used to investigate the effect of wheat canopy energy balance and water use efficiency. Wheat canopy microclimate observations were conducted from March 19 to May 24, 2007 at elongation to maturity stage. The results show that daytime total canopy sensible heat flux of FACE is higher than the ambient heat flux, while a lower latent heat flux of FACE is observed throughout the observation period. The maximum difference in wheat canopy sensible and latent heat flux between FACE and the ambient varies by 12 ~ 78 W·m^-2 and -12 ~ -63 W·m^-2 respectively. Canopy stomatal conductance from P-M calculation agrees well with measured leaf stomatal conductance of wheat, indicating that microclimate data, latent and sensible heat flux estimated from residual energy balance are accurate. Total water-use by wheat throughout the observation period is 26 mm less under FACE than that under control condition. Reduced transpiration combined with increased total biomass results in a 19% increase in water use efficiency of wheat in FACE.

Effect of long-term fertilization on the content of different forms of phosphorus in wheat

TIAN Feng-Jiao, CHEN Jun-Ping

2009, 17(2): 273-276. doi: 10.3724/SP.J.1011.2009.00273

Abstract(1337) PDF(1038)

Abstract:
Based on a long-term fertilization experiment, the effect of different fertilizations on the content of different forms of phosphorus in wheat was investigated. The results indicate that under different treatments, the contents of different forms of phosphorus in wheat grain are higher than those in the stem. In wheat grain, lecithoid phosphorus is the highest (1.19 g·kg^-1), followed by labile organic and inorganic phosphorus; whereas the content of unknown forms of phosphorus is lowest (0.348 g·kg^-1). In the stem, the content of labile inorganic phosphorus is highest (0.142 g·kg^-1) while that of labile organic phosphorus is lowest (0.034 g·kg^-1). The content of labile organic phosphorus in wheat stem under organic manure (OM) treatment is significantly lower than in the control treatment. Also the content of the other forms of phosphorus is higher under P (PK, NP, NPK, OM & 1/2OM + 1/2NPK) treatments than under non-P (CK, NK) treatments. Compared with the control treatment, the content of the different phosphorus forms and total phosphorus in wheat grain and labile inorganic P, unknown forms of P and total phosphorus in stems increases significantly under OM treatment. In wheat stem, the content of labile organic phosphorus and lecithoid phosphorus under NP treatment is higher than under other treatments. There is a significant positive correlation between the different forms of phosphorus and total phosphorus content in the grain.

Variation law of nitrate content of celery during growth period under water and fertilizer coupling

ZHANG Jie-Xia, CHEN You-Qi, MA Hai-Long, WENG Sen-Hong

2009, 17(2): 277-284. doi: 10.3724/SP.J.1011.2009.00277

Abstract(1342) PDF(1595)

Abstract:
In order to determine the effect of water and fertilizer coupling on the variation law of nitrate content in celery at the growth stage, a 3×5 orthogonal block design experiment was conducted under rain-free condition in the semiarid cold region of Northwest Hebei Province. Results show that celery nitrate content increases at early growth stage and then decreases at late growth stage, reaching its lowest at harvest under different combinations of high, moderate and low water and fertilizer. However, the nitrate content order is different for low water and fertilize treatment and also in the control treatment. Of all the treatments, only 7 (N_109.5P₃₆W₅₆₉₂) and 20 (N₂₇₀P₉₀W₄₅₀₀) treatments, low fertilizer and high water treatment, and moderate fertilizer and water treatments meet safe standards for public health. The one-factor, two-factor and three-factor effect on nitrate content under different combinations show that the effect of N increases, that of P is uncertain while that of water decreases. Unreasonable N, P, water combination restricts normal growth of celery, increases nitrate accumulation.

Variation analysis of nicotine content in flue-cured tobacco in different ecotopes

CHEN Wei, WANG San-Gen, WANG Yu-Ming, TANG Yuan-Ju

2009, 17(2): 285-290. doi: 10.3724/SP.J.1011.2009.00285

Abstract(1476) PDF(1252)

Abstract:
In this study, 12 counties in 7 provinces of China’s main tobacco cultivation areas were divided into 7 ecotopes based on geographic orientation and latitudinal difference. Then nicotine content variation in flue-cured tobacco under the same cultivation conditions in different ecotopes was analyzed. The results show extensive flue-cured tobacco nicotine content variation for different ecotopes. The degree of inter-annual nicotine content variation is highest for Liaoning and lowest for Henan and Fujian regions. Inter-annual nicotine content stability in the southern regions (Guizhou, Sichuan, Yunnan and Fujian) is higher than in the northern regions (Liaoning, Shandong and Henan). Nicotine content variation in flue-cured tobacco among different stalk parts is highest for Guizhou and Sichuan, but lowest for Liaoning. The characteristics of nicotine content in the stalk parts are more obvious for the southern than the northern regions. Nicotine content variation in the stalk parts is low for Henan region but high for Fujian region. Nicotine content variation is high in middle leaves, low in lower leaves and relatively stable in upper leaves. Nicotine content stabi- lity in the different stalk parts and grades in north are higher than in the south. Nicotine content of orange leaves is higher than lemon-yellow leaves in all the ecotopes. Nicotine content variation among the different regions is mainly driven by variation of nicotine in orange leaves of flue-cured tobacco. Difference in nicotine content from one ecotope to another is significant. Nicotine content of flue-cured tobacco is highest for Henan region and lowest for Liaoning, and is higher for the north than for the south; that in Liaoning region is approaching that in the south, while that in Yunnan region approaching the north.

Effect of herbicide spray-time on yield, quality and net photosynthesis of wheat

DANG Jian-You, PEI Xue-Xia, WANG Jiao-Ai, CHENG Mai-Feng, QU Hui-Xuan, ZHANG Ding-Yi

2009, 17(2): 291-296. doi: 10.3724/SP.J.1011.2009.00291

Abstract(1599) PDF(1187)

Abstract:
A field experiment was conducted to study the effect of 2,4-D butyl and sigma spray-time on the yield components, grain yield, quality and leaf net photosynthetic rate (Pn) of high quality wheat “Linyou 145”. Results show that Pn decreases under three spray-time of 2,4-D butyl, and decreasing rank increases with spring-time delay. Leaf and flag leaf Pn during early and middle filling stages drops compared with the control 1~15 days after sigma application in three spray-time. 2,4-D butyl applied in three spray-time shows little effect on filling parameters. Sigma prolongs filling period (S) and effective filling period (Se) but decreases average filling rate (R) and effective filling rate (Rs). Herbicide spray-time has greater effects on 1000-kernel weight and per-hectare ear than per-ear kernel. Yield decreases with later 2,4-D butyl spray. Sigma sprayed on Nov. 15 and March 20 increases flag leaf Pn during late filling stage compared with the control, and respectively increases yield by 157.44 kg·hm^-2 and 222.34 kg·hm^-2, but yield decreases by 512.71 kg·hm^-2 when sprayed on April 4. Wheat quality is improved when 2,4-D butyl is sprayed on Nov. 15 and March 20, but decreases when 2,4-D butyl is used on April 4 and sigma used in three spray-time. In summary, 2,4-D butyl and sigma sprayed on April 4 has a more obvious effect on wheat quality than sprayed on Nov. 15 and March 20. Sigma sprayed on April 4 produces the lowest yield and quality of wheat.

Effect of drought stress and water recovery on endogenous hormone content in roots of pea

YAN Zhi-Li, XUAN Chun-Xiang, NIU Jun-Yi, XI Ling-Ling, LIU Jian-Hua, ZHAO Tian-Wu

2009, 17(2): 297-301. doi: 10.3724/SP.J.1011.2009.00297

Abstract(1886) PDF(1490)

Abstract:
Pot experiment was conducted to determine the content of endogenous hormone, including Abscisic acid (ABA), Indole-3-acetic acid (IAA), Gibberellins (GA) and Zeatin (ZT), in the roots of pea (Pisum sativum Linn.) under drought stress and water recovery. The results indicate that different degrees of drought stress increase ABA and IAA contents while decreasing the contents of GA and ZT. With severe drought stress, the effects generally tend to increase. Different degrees of drought stress leads to different proportions of endogenous hormones in the roots at different growth stages. Drought has considerable impact on ZT/ABA, GA/ABA, GA/IAA and ZT/IAA ratios. But drought effect on ZT/GA, IAA/ABA ratios is insignificant. There is compensation effect of water recovery after drought stress on the 4 endogenous hormones at every growth stage which varies with growth stage, drought stress intensity and water recovery rate. Water recovery leads to variations in endogenous hormones ratio.

Effect of post-decapitation NAA-smearing on ABA and CTK content in the functional leaves of cotton plant

BAIDENGSHA, ZHANG Shi-Rong, TIAN Xiao-Li, FENG Gu

2009, 17(2): 302-306. doi: 10.3724/SP.J.1011.2009.00302

Abstract(1967) PDF(1362)

Abstract:
A pot experiment was conducted to investigate the effect of decapitation (a conventional technique in cotton cultivation in Xinjiang) on the premature senility and contents of phytohormone, carbonhydrate and chlorophyll in the functional leaves of cotton plant under low (150 mg·kg_-1) and high (500 mg·kg_-1) nitrogen application. Compared with non-decapitated plants under low nitrogen application, CTK and soluble protein content decreases while ABA and MDA content increases in decapitated plants. Both CTK and soluble protein content increases when smeared with NAA after decapitation in relation to decapitation only or non-decapitation treatments. ABA content in plants smeared with NAA after decapitation is lower than in decapitation only, but is higher than in non-decapitation treatment. ABA/CTK ratio for cotton plant with decapitation treatment is higher than in non-decapitation or post-decapitation NAA-smearing treatments. Decapitation increases plant MDA content while MDA decreases in post-decapitation NAA-smearing treatment, compared with non-decapitation treatment. Under higher N supply, ABA content under decapitation or post-decapitation NAA-smearing treatment is higher than under non-decapitation treatment. Chlorophyll content in leaves under low N supply is higher than under high nitrogen supply. Accumulation of ABA under high nitrogen supply indicates that high N might inhibit plant growth. The increase in ABA and MDA content and in ABA/CTK ratio under decapitation with low N supply suggests that decapitation enhances premature senility of cotton plants. Post-decapitation NAA smearing, on the other hand, may delay premature senility.

Allelopathic effect of oxygenic terpenoid on Echinochloa crus-galli L.

WANG Hai-Bin, HE Hai-Bin, ZENG Cong-Ming, LIN Yin-Ying, LIN Wen-Xiong

2009, 17(2): 307-311. doi: 10.3724/SP.J.1011.2009.00307

Abstract(1465) PDF(1506)

Abstract:
In this paper, five oxygenic terpenoids — (-)Carveol (C₁₀H₁₆₀), (+)Carvone (C₁₀H₁₄₀), (-)Menthone (C₁₀H₁₈₀), (-)Carvyl acetate (C₁₂H₁₈₀₂) and (+)Cedrol (C₁₅H₂₆₀) were used as test compounds and barnyardgrass(Enchinochloa crusgalli L.) receptor in rotational regression design experiment. The objective was to analyze allelopathic effect of oxygenic terpenoid on barnyardgrass. The results show that the main effects of (-)Carveol, (+)Carvone, (-)Menthone and (-)Carvyl acetate have an downward parabolic curve, while (+)Cedrol shows the opposite. Boundary effect of single factor indicates that, when single factor concentration falls below -2, the inhibition trend of the oxygenic terpenoids on barnyardgrass root length follows the order of: (-)Menthone >(-)Carveol>(+)Carvone>(-)Carvyl acetate>(+)Cedrol. When the single factor concentration is above +2, the order of inhibition trend of the oxygenic terpenoids is: (+)Cedrol>(+)Carvone>(-)Carvyl acetate>(-)Carveol>(-)Menthone. Furthermore, when the concentrations of (-)Carveol, (+)Carvone, (-)Menthone, (-)Carvyl acetate and (+)Cedrol are respectively 0.033 mmol·L^-1, 0.030 mmol·L^-1, 0.080 mmol·L^-1, 0.020 mmol·L^-1 and 0.001 mmol·L^-1, inhibition rate could theoretically reach 93.69%.

Allelopathic effect of aqueous extract from cucumber (Cucumis sativus L.)aboveground part on tomato (Lycopersicon esculentum Mill)

LIU Jian-Xin, HU Hao-Bin, WANG Xin

2009, 17(2): 312-317. doi: 10.3724/SP.J.1011.2009.00312

Abstract(1596) PDF(1605)

Abstract:
The allelopathy and its physiobiochemical mechanism of aqueous cucumber aboveground part extract on tomato were investigated under culture experiment. Chemical constituents of the extract were qualitatively analyzed using the test-tube method. The results show that cucumber aboveground part extract contains akaloids, phenols, organic acids, saponinsand, sterols, polysaccharides, protein and fats oils, but not tannins. The aqueous extract significantly inhibits the respiration rate and α-amylase activity during tomato seed germination. It also inhibits germination rate, germination index and the inhibition effect increase with increasing concentration of the aqueous extract. Watering tomato seedlings with the aqueous extract increases the contents of O₂^-., H₂O₂, glutathione (GSH) and ascorbic acid (ASA), malondialdehyde (MDA) and plasma membrane permeability in leaves of tomato seedlings and decreases catelase (CAT) and peroxidase (POD) activity. Superoxide dismutase (SOD) and ascorbate peroxidase (APX) activity initially increases and then decreases with increasing concentration of the aqueous extract. Also chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr) and dry seedling weight decrease while intercellular carbon dioxide content (Ci) increases. Kinetic data on chlorophyll fluorescence reveal that the minimal initial fluorescence (Fo) of tomato seedling leaves increases with increasing aqueous extract concentration. The maximum fluorescence (Fm), PSII potential fluorescence efficiency (Fv/Fo), PSII intrinsic photochemical efficiency (Fv/Fm), actual photochemical efficiency of PSII (ΦPSII), photochemical quenching (qP), electron transport rate (ETR) and photochemical rate (PCRNPQ) initially increases and then decreases, which is harmful to the photosynthetic structure.

Autotoxicity of aquatic extracts from chrysanthemum and rhizosphere soil on photosynthesis in the same plant species

ZHOU Kai, GUO Wei-Ming, WANG Zhi-Fang, HAO Feng-Ge

2009, 17(2): 318-322. doi: 10.3724/SP.J.1011.2009.00318

Abstract(1581) PDF(1369)

Abstract:
Autotoxicity is a major obstacle in continuous cropping under protected cultivation. Previous studies have shown that autotoxicity is a critical factor in chrysanthemum cultivation under continuous cropping. In this paper, autotoxic effects of aquatic extracts from different parts (litters, leaves, stems, roots) and rhizosphere soil of cultivated chrysanthemum “Gaoyataizi” on the photosynthesis of the same species of crop were investigated. The results show that aquatic extracts, especially the extracts of aboveground parts, significantly decrease chlorophyll content, net photosynthetic rate and leaf photosynthetic activity and stomatal conductance. It however, enhances dark respiration rate. The study shows that inhibiting photosynthesis and enhancing dark respiration is one of the mechanisms of autotoxicity in chrysanthemum.

Interaction between avermectin pretreatment and subsequent short-term heat treatment on 3rd diamondback moth instar larvae (Plutella xylostella)

GU Xiao-Jun, TIAN Su-Fen, GAO Fei, ZHAO Shi-Xi, YOU Min-Sheng

2009, 17(2): 323-329. doi: 10.3724/SP.J.1011.2009.00323

Abstract(1407) PDF(1138)

Abstract:
Interaction between avermectin pretreatment and subsequent short-term heat treatment on the 3rd diamondback moth (Plutella xylostella) instar larvae was investigated based on changes in mortality rate, pupation time, pupation rate, eclosion rate and adult emergence rate. When temperatures are set at 35 ℃ or 40 ℃ for 4 h or longer, tested insects exhibit negative effects such as significant increase in mortality rate and decrease in pupation and eclosion rates, adult emergence rate. Compared with 35 ℃, the negative effects at 40 ℃ appear earlier while pupation time delays. 0.56 mg·L^-1 avermectin toxicity significantly improves after 35 ℃ treatment for 12 h. Meanwhile heat tolerant ability of the insects to 35 ℃ treatment for 4 h or 8 h significantly improves by pretreatment with avermectin at 0.14 or 0.56 mg·L^-1. However, avermectin toxicity at 0.14 or 0.56 mg·L^-1 can significantly improve by short-term follow-up heat treatment at 40 ℃ for 2 h or longer. The tolerant ability of the insects to short-term heat treatment at 40 ℃ for 8 h is significantly weakened by pretreatment with avermectin at 0.14 mg·L^-1. 0.56 mg·L^-1 avermectin can weaken insect tolerance to short-term heat treatment at 40 ℃ for 2 h, 4 h or 8 h.

Insect community structure in spring and summer cotton fields

LU Wen-Yan, QIN Xue-Feng, XU Yan-Ling, SHEN Zong-Xia

2009, 17(2): 330-334. doi: 10.3724/SP.J.1011.2009.00330

Abstract(1381) PDF(1153)

Abstract:
Community dynamics of major insect in spring and summer cotton fields were investigated according to the theory and method of community ecology from June 26 to August 20, 2007. The community structure dynamics was analyzed based on collected data on relative richness, dominance index, dominant concentration index, diversity index and evenness. The results show a rich constitution of insect communities in spring and summer cotton fields. About 48 insect species, belonging to 35 families and 10 orders are observed. In spring cotton field, the insect community comprises 39 species, 30 families and 9 orders while in summer cotton field, the insect community comprises of 43 species, 30 families and 10 orders. The dominant species are Aphis gossypii, Bemisia tabaci and Tetranychus cinnarinus. The dominant species in spring cotton field is T. cinnarinus from the end of June to the beginning of July, reaching the peak at the beginning July. The dominant species after mid. July is A. gossypii, and B. tabaci from the end of July to mid. August in the two cotton fields. Total individual numbers of insect community vary greatly. The total individual numbers of insect community and pest sub-community in spring cotton fields are always higher than in summer cotton fields. Relative richness of pests in spring cotton fields and that of the natural predator in summer cotton fields are larger. Similarity coefficient of parasitical natural predator is highest (0.949 4) and that of phytophagous pest community is lowest (0.439 4). The highest diversity indices of insect community in spring cotton fields and summer cotton fields are 1.895 3 and 2.095 1 respectively. Changes of diversity and evenness are similar in both cotton fields. However, change in aggregation index of dominance is contrary to that of diversity and evenness, which increases with decline in diversity and evenness.

Effect of soil on colonization and growth promotion-function of Streptomyces sp. S506

WANG Su-Fang, WANG Zhan-Wu, LI Hong-Tao, ZHANG Cui-Mian, ZHAO Bao-Hua

2009, 17(2): 335-338. doi: 10.3724/SP.J.1011.2009.00335

Abstract(1396) PDF(1157)

Abstract:
Isolated Streptomyces sp. S506 from tomato rhyzosphere is one of the beneficial strains which can promote root growth, control soil-borne diseases and attenuate root autotoxicity. In this paper, the effect of soil texture, temperature and moisture on Streptomyces sp.S506 colonization in tomato rhizosphere and growth-promotion effect of Streptomyces sp. S506 on tomato seedling were studied through pot experimentation. The results show that optimum soil texture order for Streptomyces sp. S506 colonization in tomato rhizosphere and the corresponding expression of growth-promotion function is loamy soil, followed by sandy soil and then clay soil. In the tested temperature gradient, the optimum temperature order for Streptomyces sp. S506 colonization is 30 ℃, 22.5 ℃ and the 15 ℃; and that for growth-promotion function expression is 22.5 ℃, 30 ℃ and 15 ℃ respectively. The optimum soil relative moisture order for colonization and growth-promotion function expression of Streptomyces sp. S506 is 20%, 25%, 15% and 30%. This study enhances our knowledge on the role of soil environment on the colonization and function expression of target strains in tomato rhizosphere.

QTL mapping of rice leaf photooxidation tolerance control

SUN Xiao-Xia, DENG Jia-Yao, JIANG Bao-Yue, JIA Xiao-Li, LIN Wen-Xiong

2009, 17(2): 339-342. doi: 10.3724/SP.J.1011.2009.00339

Abstract(1504) PDF(1307)

Abstract:
A linkage map consisting of 97 SSR markers was constructed using 123 F12 lines (recombinant inbred lines, RILs) derived from crossing between “Lemont” and “Dular” rice cultivars. QTL analysis was conducted for flag leaf photooxidation tolerance, including tolerance index (T) and sensitivity index (S). Using WinQTLcart 2.5 software, a total of eleven QTLs are detected with percentage variance explanation (PVE) of 6%~23%, and LOD of QTLs of 2.02~5.07. Of the QTLs, seven tolerance indices are detected on chromosomes 1, 2, 3, 6 and 8, with PVE of 6%~19%; four controlling sensitivity indices are detected on chromosomes 1, 3, 5 and 8, respectively explaining 19%, 23%, 6% and 7% of total phenotypic variation. On the basis of both traits, two QTLs for tolerance index and sensitivity index are co-localized around RM85~RM468 and RM408~RM250 respectively, which could explain negative significant correlation between tolerance index and sensitivity index, i.e . the pleiotrophic effect.

Effect of lanthanum on the germination and peroxidase activity in sorghum under acid-rain stress

QIU Lin, WANG Na, ZHOU Qing

2009, 17(2): 343-347. doi: 10.3724/SP.J.1011.2009.00343

Abstract(1519) PDF(1604)

Abstract:
The effect of lanthanum on the germination, MDA content and peroxidase (POD) activity in sorghum seeds under acid-rain stress were investigated. The objective of the study was to develop a scientific method and technical guide for mitigating acid-rain damage on seed germination. Results show that sorghum seeds germinate best when seed soaked in 12 mg·L^-1 La(Ⅲ) solution, damage on seed germination from acid-rain decreases. Germination rate, germination energy, germination index, vigor index are all higher than untreated seeds. Abnormal germination in treated seeds also tends to be lower than untreated, especially at pH 2.5. Because internal structure of seeds is destroyed by acid-rain with pH 2.0, La(Ⅲ) cannot reverse damage by acid-rain at pH 2.0. MDA content and POD activity of La(Ⅲ) treatment groups are lower than the non-La(Ⅲ) treatments, especially at pH 2.5 and 2.0. This indicates that La(Ⅲ) probably decreases membrane lipid peroxidation induced by acid-rain through POD activity adjustment, which eventually alleviates acid-rain damage on seed germination.

Methods and techniques for comprehensive agricultural eco-economic system assessment

YAN Lu-Ming

2009, 17(2): 348-353. doi: 10.3724/SP.J.1011.2009.00348

Abstract(1435) PDF(1343)

Abstract:
A research was conducted on the comprehensive assessment of agricultural eco-economic systems in Fujian Province. Using GIS & RS along with mathematical methods, a series of data collection and discrimination of original indicator data was performed. A frame of comprehensive indicator system of assessment of agricultural eco-economic system (with 5 levels including top, status, norm, variable and element) was set up. Original combination indicators were transformed into comparable indices by the de-dimensionalization. The indicator weight was ascertained based on entropy weight method and the indicator system gradually converged. Using GIS platform, the spatial distribution of the agricultural eco-economic levels for the cities/counties were analyzed and extreme phenomena exposed. Such information can be used as a guiding reference at different levels of agricultural decision-making.

Sustainable development analysis from ecological footprints of traditional agricultural areas— A case study of Congjiang County of Guizhou Province

JIAO Wen-Jun, MIN Qing-Wen, CHENG Sheng-Kui, ZHANG Dan, YANG Hai-Long, HE Lu, LIU Shan

2009, 17(2): 354-358. doi: 10.3724/SP.J.1011.2009.00354

Abstract(1329) PDF(1329)

Abstract:
Due to some natural and historical reasons, Congjiang County of Guizhou Province has been maintaining a typically traditional rice-fish system that is characterized by both traditional ecological agriculture and distinctive cultural heritage. In order to appreciate the values of this kind of agricultural heritage and to provide theoretical basis for its rational protection, this paper analyzed the ecological footprint composition of the agricultural heritage site, Congjiang County, summarized the characteristics of resource consumption of the traditional agricultural area and revealed the significance of the traditional agriculture in regional ecological conservation, resource consumption and sustainable development. Results show that the footprints for food and shelter occupy a very high proportion, respectively registering 45.9% and 33.3% of the total footprint demand, which results in a high occupation of arable land and forest; the occupation of CO₂ area, however, is comparatively small, accounting for only 3.0% of the total footprint while the combustion of fuel wood provided by forest is a major part of the local energy footprint, which is dramatically different from that of industrialized regions characterized by fossil fuel combustion. Low resource consumption has enabled Congjiang County to maintain in an ecological balance with the ecological surplus of 0.058 1 hm2 per capita in 2007. Hence it can be seen that traditional agriculture plays a very important role not only on regional ecological conservation and cultural heritage but also on sustainable regional socio-economic development through changing the agricultural production mode and consumption patterns of local people.

Trend of crop water requirement in recent 35 years in Hebei Province

LI Chun-Qiang, LI Bao-Guo, HONG Ke-Qin

2009, 17(2): 359-363. doi: 10.3724/SP.J.1011.2009.00359

Abstract(1568) PDF(1354)

Abstract:
Long term changes of crop water requirement (CWR) and reference evapotranspiration have a significant effect on agricultural production and water resources management. Based on historical meteorological data, reference evapotranspiration (ETo), crop water requirement (derived by multiplying ETo by crop coefficient) and crop water deficit (the difference between crop water requirement and rainfall) were calculated using modified FAO Penman-Monteith equation. The change trend was then analyzed for winter wheat and maize in Hebei Province for the period 1965 ~ 1999. Results show a significant decrease in reference evapotranspiration and crop water requirement. Decrease in CWR is 26 mm per decade for winter wheat and 9.7 mm and 9.9 mm for summer and spring corn respectively. There are differences in water deficit among different crops but the average increase in water deficit is insignificant, which is respectively 345 mm, 20 mm and 29 mm per year for winter wheat, summer corn and spring corn.

Dynamic assessment and forecasting of provincial eco-environmental quality from matter element model and Markov chain— A case study of Jiangxi Province

LIU Yao-Bin, ZHU Shu-Fen

2009, 17(2): 364-368. doi: 10.3724/SP.J.1011.2009.00364

Abstract(1532) PDF(1166)

Abstract:
By developing a characteristics indicator system of eco-environmental matter elements, this paper advanced an assessment and forecasting method of provincial eco-environmental quality based on the matter element model and Markov chain. The system was applied to Jiangxi Province as case study. The results show that eco-environmental quality in Jiangxi Province as simulated by matter element model has been, on the overall, improved from 2000 to 2005. The degree of improvement is, however, different for the 11 districts in the province. On the other hand, Markov chain forecast shows that the eco-environmental quality seems heading in a better evolutional direction in the next 5~10 years, provided current eco-environment governance is sustained. The application effects imply that the assessment and forecast of the models, to a certain extent, reflect actual conditions and development trends of the provincial eco-environmental quality. However, because of limitations in the model assumptions, improvements are needed in application of the model to different regions in different phases of economic development.

Ecological and environmental water requirement in the middle Yellow River

WANG Hui-Xiao, XUE Ming-Jiao, QIN Long-Hua

2009, 17(2): 369-374. doi: 10.3724/SP.J.1011.2009.00369

Abstract(1667) PDF(1308)

Abstract:
As a significant factor for maintaining river ecosystem function, ecological and environmental water requirement of rivers is a key issue of hydrological research. Based on real conditions of the middle Yellow River, a few methods (Montana method, minimum monthly mean discharge method, etc.) were adopted to calculate ecological and environmental water requirement of the river. The results show that in the middle Yellow River the environment water requirement is 47.356×10⁸ m³, the water requirement for sediment delivery is 40.666×10⁸ m³, and the water surface evaporation is 10.314×10⁸ m³. Total tributary ecological and environmental water requirement from Kuye River, Wuding River, Fen River, Jing River, Beiluo River, Wei River, Yiluo River, and Qin River is respectively 2.071×10⁸ m³, 3.393×10⁸m³, 10.143×10⁸ m³, 8.699×10⁸ m³, 3.575×10⁸ m³, 34.601×10⁸ m³, 6.481×10⁸ m³ and 2.505×10⁸ m³. Due to the non-independence of the middle Yellow River, further ecological and environmental water requirement research is recommended.

Bioenergy, reduction of energy consumption and waste discharge, and low-carbon economy

CHENG Xu

2009, 17(2): 375-378. doi: 10.3724/SP.J.1011.2009.00375

Abstract(2175) PDF(2004)

Abstract:
The term ‘biomass’ has been frequently used in recent years. Borrowing from ecology, it refers to bio-energy and bio-based materials which can significantly substitute for fossil fuel and reduce GHG (green house gases) emission. China’s agriculture is a major consumer of fossil fuel and releaser of GHG. It may contribute to the less energy consumption and GHG emission in the nation. Agriculture is a unique industry that produces biomass—a renewable feedstuff of bioenergy. In the transition period from conventional high-carbon economy to low-carbon economy, bioenergy plays an important role in enriching China’s eco-agriculture.

Research advances in plant competition in agroforestry systems

MAO Rong, ZENG De-Hui

2009, 17(2): 379-386. doi: 10.3724/SP.J.1011.2009.00379

Abstract(1621) PDF(1776)

Abstract:
Plant competition plays an important role in the success and sustainability of agroforestry systems. Minimizing competition and maximizing resource utilization increase crop yield and overall productivity of agroforestry systems. This paper introduces the concept and theory of plant competition, reviews competition for light, water and nutrient among trees and crops, and summarizes allelopathy and competition related plant traits in agroforestry systems. Aboveground competition for light among trees and crops is a major constraint under humid climate conditions, while belowground competition for water predominates in semi-arid tropics and temperate agroforestry systems. In agroforestry systems, plant competitive ability for light is decided by leaf area, canopy structure, et al. Root traits related to belowground competitive ability include occupied soil space, morphological and physical elasticity and spatial and temporal soil partitions. It is suggested that future research on agroforestry systems focus on comparisons among different components in different climatic conditions, competition processes and physiological mechanisms, plant allelopathy and the role and mechanism of mycorrhizae in plant competition, interactions between above- and below-ground competition and the effect of global climate change on plant competition of the agroforestry systems.

Biological effect of agricultural application of rare earth elements on nucleic acid

WANG Li-Hong, ZHOU Qing

2009, 17(2): 387-392. doi: 10.3724/SP.J.1011.2009.00387

Abstract(1550) PDF(1795)

Abstract:
The extensive application of rare earth elements in agricultural practices in China has brought remarkable economic benefits. However, environmental safety concerns from rare earth element use in agriculture are growing in the Chinese and foreign scientific community. Nucleic acid is a polymer that stores and transfers genetic information. This paper reviews the effect of rare earth on nucleic acid and its mechanisms from the point of view of genetics. It is indicated that rare earth binds with nucleic acid or hydrolyzes nucleic acid. Binding sites of Ln3+ with nucleic acid, mode of action and hydrolytic mechanisms are elucidated. Finally, the future direction of research in this field is proposed.

An overview of ecological degradation and restoration of Eucalyptus plantation

YU Fu-Ke, HUANG Xin-Hui, WANG Ke-Qin, DUAN Chang-Qun

2009, 17(2): 393-398. doi: 10.3724/SP.J.1011.2009.00393

Abstract(1840) PDF(2950)

Abstract:
New research advances in ecological degradation and restoration of Eucalyptus plantation were analyzed from the point of view of eco-environmental effect of Eucalyptus plantation in recent past. Three cognitive conclusions were arrived at: Ecological degradation of Eucalyptus plantation usually leads to soil degradation, decrease in biodiversity and forestland productivity. These are mainly driven by soil and water loss in forestlands, unreasonable human activity and allelopathic effect of Eucalyptus species. Scientific strategy and technology such as soil and water conservation, biodiversity protection and forestland productivity regulation must be implemented in ecological restoration of Eucalyptus plantation. Multi-disciplinary research on ecological adaptability and eco-environmental effect of Eucalyptus species at molecular and cellular levels could be a promising direction of future studies on ecological degradation and Eucalyptus plantation restoration. Moreover, exploring ecological relationship between Eucalyptus species and other exotic plant species is key to successful future studies.

Effect of soil ecology modifier T1010 on soil environment improvement in solar-greenhouse in Shouguang City

CHEN Wei-Jing, CHEN Jian-Ai, YANG Huan-Ming

2009, 17(2): 399-401. doi: 10.3724/SP.J.1011.2009.00399

Abstract(1763) PDF(1321)

Abstract:

Inhibitive bioactivity of azadirachtin on phytopathogens

YE Min, LI Cheng-Yun, XIAO Chun, LI Yong-Ming

2009, 17(2): 402-404. doi: 10.3724/SP.J.1011.2009.00402

Abstract(1171) PDF(1222)

Abstract:

Agroecology：role of discipline

2009, 17(2): 484-484. doi: 10.3724/SP.J.1011.2009.00484

Abstract(544) PDF(658)

Abstract:

2009 Vol. 17, No. 2