中国生态农业学报(中英文)

Effects of different conservation tillage measures on soil organic carbon pool in two sequence rotation systems of spring wheat and pease

CAI Li-Qun, QI Peng, ZHANG Ren-Zhi, LI Ai-Zong

2009, 17(1): 1-6. doi: 10.3724/SP.J.1011.2009.00001

Abstract(1609) PDF(1452)

Abstract:
A 5-year conservation tillage experiment was conduced in Lijiabu, Dingxi City of Gansu Province to study the effects of crop rotation and tillage on soil total carbon, active organic carbon, microbial biomass carbon and soil organic carbon pool management index. The results show that conventional tillage with straw mulching and conventional tillage, in which straw is plowed into soil, increase soil organic carbon, active organic carbon, microbial biomass carbon and soil carbon pool management index under both rotation sequences. Though zero-tillage increases soil carbon pool management index in 0 ~5 cm soil layer, it decreases index of the other soil layers. The findings then suggest that zero-tillage without straw mulching or straw plowing into the soil is non-sustainable for soil organic carbon management.

Effect of monoculture and intercropping on radiation use efficiency and yield of maize and soybean

GAO Yang, DUAN Ai-Wang, LIU Zu-Gui, SHEN Xiao-Jun, LIU Zhan-Dong, CHEN Jin-Ping

2009, 17(1): 7-12. doi: 10.3724/SP.J.1011.2009.00007

Abstract(1567) PDF(1895)

Abstract:
Field experiments were conducted to investigate the effect of two intercropping patterns (maize-soybean 1︰3 and 2︰3) and corresponding monoculture on the capture and use of solar radiation and on yields of maize and soybean in two growing seasons (2006 and 2007). Results show that light extinction coefficients of monocultured maize and soybean, and 1︰3 and 2︰3 intercropping are 0.45, 0.60, 0.53 and 0.52 respectively. There is no significant maize biomass difference between the intercropping and monoculture before 79 days after sowing. After the 79-day period, maize biomass in 1︰3 intercropping becomes significantly higher than that of maize monocultured at 0.01 probability level. There is a significant difference in maize biomass between 1︰3 and 2︰3 intercropping at 0.05 probability level. Soybean biomass of intercropping and monoculture is significantly different. RUE value of 1︰3 (3.51 g·MJ^-1) and 2︰3 intercropping (3.49 g·MJ^-1) is about 2.8 times that of monocultured soybean (1.24 g·MJ^-1). However, it is slightly less than that of the monocultured maize (3.56 g·MJ^-1). Grain yields for monoccultured maize and soybean are more than those for intercropping treatments. However, total yields for intercropping treatments are 6.0% and 320% higher than the yields for monocultured maize and soybean respectively. Incomes from the two intercropping systems are 56% ~ 60% and 70% ~ 74% higher than those from monocultured maize and soybean. The findings suggest that intercropping may help increase crop production through more efficient utilization of solar radiation, hence increase farmers’ income.

Effects of alternate furrow-irrigation on crop water consumption,yield and quality of cotton

WANG Zhen-Chang, DU Tai-Sheng, YANG Xiu-Ying, TANG Qing-Yun

2009, 17(1): 13-17. doi: 10.3724/SP.J.1011.2009.00013

Abstract(1731) PDF(1036)

Abstract:
A field experiment was carried out to study the effect of alternate furrow-irrigation (AFI) on water consumption characteristics, yield and quality of seed cotton in the oasis region of downstream Shiyang River Basin of Gansu Province. In the early stages of cotton growth (squaring to flowering stages), diurnal crop water consumption under conventional furrow-irrigation (CFI)is higher than in AFI. In the late stages (bolling to open-boll stages), diurnal crop water consumption under AFI is higher than in CFI. Under the same irrigation pattern, AFI improves yield of total seed cotton and seed cotton yield before frost. When irrigation is 375m³·hm^-2 and 480 m3·hm^-2, seed cotton yield and water use efficiency (WUE) under AFI are significantly higher than in CFI. In the two years, the difference in percent lint between AFI and CFI is insignificant. In 2005, average fiber length under AFI is 2.6 mm longer than in CFI, with a significant difference when irrigation is 225 m³·hm^-2. In 2006, no significant difference exists between AFI and CFI in fiber length. This can be attributed to different precipitation events in the two years. It is concluded that AFI is a feasible method of cotton cultivation in the oasis of Shiyang River Basin. With no reductions in fiber quality, AFI increases both seed cotton yield and water use efficiency.

Effect of sowing date on growth and yield of spring-maize

LIU Ming, TAO Hong-Bin, WANG Pu, YI Zhen-Xie, LU Lai-Qing, WANG Yu

2009, 17(1): 18-23. doi: 10.3724/SP.J.1011.2009.00018

Abstract(2232) PDF(2291)

Abstract:
Two sowing dates (April 24 and May 15) and two genotypes (“Zhengdan958” and “Ludan984”) were used to investigate the effect of meteorological change on the growth, development and yield of spring-maize. The results indicate significant differences in the growth and yield of spring-maize under different sowing dates. Yield of spring maize sown on May 15 increases by 2 157 kg·hm^-2 for “Zhengdan958” and 1 137 kg·hm^-2 for “Ludan984” than those sown on April 24. 1000-grain weight difference between two sowing dates and genotypes are insignificant. Difference in grain number per ear-corn is insignificant between the two genotypes, but significant between the two sowing dates. Grain number per ear-corn for spring-maize sown on May 15 increases by 37.8％ in “Zhengdan 958”and 11.2% in “Ludan 984” over those sown on April 24. Kernel number decline constitutes the main reason for low grain yield in spring maize which is driven by climatic factors. Precipitation affects yield by decreasing kernel number. Low temperature and solar radiation, due to high precipitation during flowering, leads to low pollination, hence low kernel number. Also the lack of dry matter accumulation as a result of low precipitation during 6-to-12-leaf stage affects kernel development. Thus May 15 is a better sowing date for the high yield. Determining appropriate sowing date and reducing the negative effects of precipitation on yield are key factors for high yield spring-maize in North China Plain.

Effect of different proceding crops on yield, quality of cucumber and soil enzyme activity in solar greenhouse

HE Li-NA, LIANG Yin-Li, XIONG Ya-Mei, ZHOU Mao-Juan, GAO Jing, WEI Ze-Xiu

2009, 17(1): 24-28. doi: 10.3724/SP.J.1011.2009.00024

Abstract(1168) PDF(1034)

Abstract:
Dynamic changes in cucumber yield, quality, soil respiration and enzyme activity were studied under different proceding crops in different growing seasons in Yan’an solar greenhouse. The results show that cucumber yield and soil alkaline phosphatase activity are high under cowpea-cucumber rotation. Soil respiration and cucumber soluble sugar content significantly increase under tomato-cucumber rotation. Vc content of cucumber improves significantly under kidney bean-cucumber rotation. Soil urease activity and nitrate content of cucumber also increase under maize-green manure-cucumber rotation. And sucrase activity in the soil is highest under black bean-green manure-cucumber rotation system. For high cucumber yield, cowpea-cucumber rotation system is the most suitable model. However, tomato-cucumber and kidney bean-cucumber rotation systems are the most suitable models for improving cucumber quality.

Effect of wheat cultivar mixtures on wheat yield and stripe rust

CHEN Qi-Cun, ZHU You-Yong, LI Zhen-QI, TANG Yong-Sheng, KANG Zhen-Shenf

2009, 17(1): 29-33. doi: 10.3724/SP.J.1011.2009.00029

Abstract(1187) PDF(1029)

Abstract:
Field experiment involving six cultivar-mixed combinations from seven wheat cultivars (“Fan19”, “Yin11-12”, “Chuanmai107”, “Jingmai10”, “Qingchun55”, “46548-3” and “An96-8”) was conducted in a multi-site setting from 2003 ~ 2006 in Qujing, Yunnan Province to evaluate the effects of mixed planting of different wheat cultivars on yield and stripe rust severity under natural disease conditions. Overall, the effect of cultivar mixture on yield is +3.9%. The frequencies of positive, neutral and negative effects on yield are 69.4%, 8.3% and 22.3% respectively. Individual environmental conditions like site location and year affect cultivar mixture effect on yield. In years when stripe rust is relatively severe, all mixed combinations reduce disease index of stripe rust. Thus using cultivar mixtures can have practical implications for wheat production in China.

Community structure of soil macrofauna under different land-use systems in the purple hilly areas of Sichuan Basin

WU Yu-Hong, CAI Qing-Nian, KIN Chao-Wen, CHEN Yi-Bing, LI Yu-Ying, CHENG Xu

2009, 17(1): 34-40. doi: 10.3724/SP.J.1011.2009.00034

Abstract(1423) PDF(1338)

Abstract:
In winter 2006 and spring 2007, soil macrofauna were investigated in four land-use systems (field margin, farmland, orchard and forestland returned from farmlands) in the purple hilly areas of Sichuan Basin. The soil macrofauna were manually sorted. A total of 2 838 soil individual macrofauna were captured and classified into 3 phyla and 9 classes. Results of the study show that individual density, group number and DG diversity index of soil macrofauna communities significantly vary with land-use systems. Individual density is significantly higher in field margins than in other forms of land-use, especially in the winter season, group number and DG diversity index are significantly higher in field margins than in farmlands and returned forests. The lowest individual density, group number and DG diversity index exists in farmlands. Individual density and group number decrease with increasing soil depth in the four land-use systems. Jaccard and Grower coefficients have a high similarity among soil macrofauna communities in field margin, orchard and returned forestland. A low similarity is observed among soil macrofauna communities in farmland and field margin, farmland and orchard, farmland and returned forest. The findings suggest that soil macrofauna communities are strongly influenced by land utilization. Also, field margin plays an important role in conserving soil macrofauna.

Content and seasonal change in soil labile organic carbon under different forest covers

ZHANG Jian, WANG Xi-Long, WANG Qing-Kui, LIU Yan-Xin

2009, 17(1): 41-47. doi: 10.3724/SP.J.1011.2009.00041

Abstract(1635) PDF(1623)

Abstract:
Based on the concentrations of soil labile organic carbon (SLOC) pools under native evergreen broad-leaved forest (NBF), and three plantations of pure Cunninghamia lanceolata , pure Michelia macclurei and their mixed forest in different seasons, the effect of forest types on the content and seasonal changes of SLOC was analyzed for Huitong County of Hunan Province. The results show that SLOC content decreases after native evergreen broad-leaved forest are substituted by planted forest. Compared with C. lanceolata plantation, C. lanceolata and M. macclurei mixed forest (MCM) increases SLOC content. However, the difference is statistically insignificant except for water-soluble organic carbon (WSOC). Substantial seasonal fluctuations in SLOC under forests are observed. Throughout the year, WSOC decreases in the following order of NBF > MCM > pure M. macclurei plantation (PM) > pure C. lanceolata plantation (PCF). For soil microbial biomass carbon (MBC), hot-water extractable C (HWC) and hot-water extractable carbohydrate-C (HWcC) is in the following order of NBF > PM > MCM > PCF. Compared with PCF, MCM increases soil quality. However, seasonal trends of SLOC under different forest covers are not completely consistent, suggesting that seasonal fluctuations in SLOC are influenced not only by climatic factors like temperature and precipitation, but also by vegetation type.

Effect of different fertilization systems on rice yield components and their stability

HU Jian-Li, WANG De-Jian, WANG Can, SUN Rui-Juan

2009, 17(1): 48-53. doi: 10.3724/SP.J.1011.2009.00048

Abstract(1795) PDF(1829)

Abstract:
Rice yield components including productive tillers per hill, average yield per panicle and yield per hill under different fertilization systems were researched into in a long-term nutrient recycling experiment at the Changshu National Agroecological Experimental Station (31°33′ N, 123°38′ E). The indices for yield-related traits were collected in a single rice growing season and regression analysis used to determine the quantitative relationship between nutrient content in the rice plants at booting stage and the yield components and their stability. Results of the study show that nitrogen fertilizer favors productive tiller number increase, but dramatically inhibits per panicle average yield. Average productive tillers per hill under N treatment are 4.2, 0.9 and 0.7 higher than under CK, NP and NPK respectively. The application of nitrogen along with phosphorus eliminates the conflict between productive tillers and per panicle average yield and therefore boosts per hill yield of rice. Productive tillers and per hill yield of rice increase with the addition of pig manure, but per panicle average yield does not significantly change. Only the stability of per hill productive tillers is significantly affected by chemical fertilizer treatments. The other two yield components are not affected by chemical fertilizer or pig manure treatments. Average coefficient of variation of productive tillers under CK, N, NP and NPK are 19.5%, 17.9%, 18.3% and 22.9% respectively. Thus potassium fertilization increases productive tillers CV. There is a good fit of the linear regression model for yield-related trait indices and N and K contents of plants at booting stage. The average CV of productive tillers is directly related with K content of rice plant.

Effect of nitrogen on vertical distribution of canopy nitrogen and chlorophyll relative value (SPAD value) of summer maize in sub-humid areas

DANG Rui-Juan, LI Shi-Qing, MU Xiao-Hui, LI Sheng-Xiu

2009, 17(1): 54-59. doi: 10.3724/SP.J.1011.2009.00054

Abstract(1509) PDF(1027)

Abstract:
A field experiment was carried out in sub-humid area using Eum Orthic Authrosols as sample soil type. The experiment analyzed the vertical distribution pattern of canopy leaf nitrogen and leaf chlorophyll relative value (SPAD value), differences in different layer-leaves for different nitrogen levels in summer-maize (Zeamays L.) at three growth stages (jointing, grain filling and maturity) and correlation for layer-leaf nitrogen content, leaf SPAD value and applied N. The results show that different layer-leaves have different nitrogen content which obviously diminishes from the upper to middle, then the lower leaf canopy. Based on the average of different leaf layers for the entire growth stage, upper leaf layer is 6.64% higher than middle leaf layer, which in turn is 5.18% higher than the lower leaf layer. With increasing application of nitrogen, the difference between upper and middle leaf layers increases. However, the difference between middle and lower leaf layers decreases with increasing nitrogen application. The vertically changing trend of canopy leaf chlorophyll relative value is similar to that of nitrogen content of leaves. Correlation analysis indicates a significant (R = 0.503^**) linear correlation between chlorophyll relative value and leaf nitrogen content throughout the growth stage. Further analysis indicates that the upper leaf layer has the most closed correlation of leaf nitrogen content, chlorophyll relative value with applied nitrogen. So the best diagnosis of nitrogen nutrition for summer-maize is in the upper leaf layer.

Effect of fertilizer application on nutritive quality and growth of hybrid sorghum grass

ZHOU Huai-Ping, HAO Bao-Ping, GUAN Chun-Lin, XIE Wen-Yan

2009, 17(1): 60-63. doi: 10.3724/SP.J.1011.2009.00060

Abstract(1385) PDF(1066)

Abstract:
The study on effect of fertilizer application on nutritive quality and growth of hybrid sorghum grass shows that application of mixed NPK fertilizer not only improves hybrid sorghum grass biomass but also increases its output per unit area in terms of crude protein, crude fiber and crude fat. Among the factors influencing biomass production, the N produces the best effect followed by P and K. Plant height and variability of crude protein, crude fiber and crude fat contents mainly depend on variety characteristics. Fertilizer application impacts output per unit area of crude protein, crude fiber and crude fat mainly through biomass variation in hybrid sorghum grass. With regard biomass amount and quality of hybrid sorghum grass, optimum harvesting time is from post floral stage to intermediate maturity stage. If hybrid sorghum grass is harvested early or late, its biologic yield drops. The quality is much inferior at late harvesting.

Effect of microelement deficiency on root exudates of ginseng

LI Yong, HUANG Xiao-Fang, DING Wan-Long

2009, 17(1): 64-69. doi: 10.3724/SP.J.1011.2009.00064

Abstract(1223) PDF(1843)

Abstract:
Changes in principal root exudates of referenced 3-year-old ginseng plants in different hydroponic trial treatments [one-Hoagland nutritional solution (CK) and nutritional solution free B, Mn, Zn and Fe elements, respectively] were measured and compared. The results show that in all 5 treatments including CK, 23 ~ 30 components are detected, including alcohol, fatty acids, fatty acid esters, phenolic acids and their derivatives, aldehydes, etc. further analysis shows that except for the 20 components detected in root exudates of the 5 treatments, compared with ck, components of other groups decrease and fatty acids and phenolic acids components increase under microelement deficiency treatments. The results imply that microelement deficiencies have significant effect on the composition of ginseng root exudate.

Spatial characteristics and yield increasing potential of fertilizer consumption among different regions of Xinjiang

CHEN Xi-Mei, XING Hei-Gang, ZHAO Ming-Yan

2009, 17(1): 70-74. doi: 10.3724/SP.J.1011.2009.00070

Abstract(1257) PDF(1466)

Abstract:
Based on official statistical data for 1989 ~ 2005, the characteristics of chemical fertilizer application in different regions of Xinjiang were analyzed. The relationships between yield and chemical fertilizer application in different regions were also investigated. Based on fertilizer application level in different regions, Xinjiang was divided into three zones, high application zone (219.59 kg·hm^-2), medium application zone (175.93 kg·hm^-2) and low application zone (115.88 kg·hm^-2). Grain yield index increase (GYII) per additional kilogram fertilizer application decreases in the following order: medium application zone (21.45 kg grain per kg fertilizer) > low application zone (13.88) >high application zone (10.80). High application zone has the lowest yield increase potential while medium and low application zones have higher yield potential. It implies more fertilizer utilization in the medium and low application zones in order to improve grain production in Xinjiang.

Effect of chemical fertilizer application on grain yield in Qitai County,Xinjiang Uygur Autonomous Region

ZHAO Ming-Yan, XING Hei-Gang, CHEN Xi-Mei

2009, 17(1): 75-78. doi: 10.3724/SP.J.1011.2009.00075

Abstract(1092) PDF(1374)

Abstract:
Based on official statistical data from 1989 to 2005, the characteristics of chemical fertilizer application in Qitai County, Xinjiang Uygur Autonomous Region were investigated by time series analysis. Then the relationship between grain yield and chemical fertilizer application was established through correlation analysis. Results show that average chemical fertilizer application in the county is influenced by the price of grains and fertilizers. From 1989 to 2005, fertilization application increased from 65.65 kg·hm-2 to 159.43 kg·hm^-2 and peaked in 1998 at 196.6 kg·hm^-2. The proportion of NPK fertilizer is moderate and has clearly increased grain yield. A significant direct correlation exists between grain yield and chemical fertilizer application rate. With increase in chemical fertilizer application, grain yield increases by many folds. When chemical fertilizer application is above 170 kg·hm^-2, increase in grain yield ceases to be significant. The best strategy is to control fertilizer application amount to avoid the potential pollution and other negative impacts. This can be achieved by paying appropriate attention to scientific application of fertilizers and sustainable development of agricultural production.

Characteristics of gas exchange in sweet potato leaf under differentsoil water content and fertilization

XU Yu-Bing, SONG Ya-Zhen, LI Shi-Qing

2009, 17(1): 79-84. doi: 10.3724/SP.J.1011.2009.00079

Abstract(1241) PDF(1197)

Abstract:
To understand the effect of soil water and fertilization on gas exchange in two cultivars of sweet potato leaf (“Qinshu 4” and “619”), photosynthesis rate (Pn), water use efficiency (WUE), transpiration rate (Tr), stomatal conductance (Gs), stomatal limitation (Ls) and intercellular CO₂ (Ci) were measured in a pot experiment. Results show that soil water has a significant influence on Pn, Tr, WUE, Ls, Gs and Ci of sweet potato. Fertilization has marked effect on these indexes as well, except for Gs in “Qinshu4” cultivar. With the decrease of soil water, a reducing tendency is found for Pn, Tr of sweet potato. Under light soil drought, Gs and Ls slightly decrease or increase but the change in Ci is unapparent. Under severe soil drought, however, both Gs and Ls significantly drop, while Ci increases significantly. WUE of “Qinshu 4” decreases with decreasing soil water content while light soil drought significantly enhances WUE in “619”, relative to CK or severe soil drought. Change in Ls and Ci with decreasing soil water content indicates that gas change in sweet potato leaf is mainly limited by stomatal factors under slight soil drought, and non-stomatal factors under severe soil drought. Sweet potato Pn is enhanced with increasing fertilization. Relative to CK, Tr slightly drops in “Qinshu 4” or significantly increases in “619” at moderate fertilization. However, Pn in the two varieties significantly increases at high fertilization. WUE apparently increases at moderate fertilization though high fertilization does not lead to any positive effect. The effect of fertilization on Gs is positive for “619” and insignificant for “Qinshu 4”. With improvement in soil nutrient, Ls initially shows an increasing tendency but eventually decreases. For Ci, leaf gas exchange is mainly limited by stomatal factors under moderate fertilization and non-stomatal factors under high fertilization. A significant interaction exists between soil water content and fertilization for all six indices. This suggests that Pn, Tr and WUE of sweet potato can be improved by selecting appropriate fertilization and soil water content. However, the degree of response to fertilization is different for the two varieties.

Effect of varying red soil moisture on amino acid and polyamine content in citrus (Citrus unshiu Marc.) leaves

ZHOU Jing, WANG Tian, CUI Jian, HU Feng, LI Hui-Xin, ZHANG Bin

2009, 17(1): 85-89. doi: 10.3724/SP.J.1011.2009.00085

Abstract(1118) PDF(1346)

Abstract:
In this study, 2-year pot seedlings of satsuma mandarin (Citrus unshiu Marc.cv. Miyagawa Wase) were selected and grown in Quaternary red clay soils to explore how varying soil water content impacts the ecophysiological factors of the citrus plant. Soil water content was monitored in real time by FDR and strictly controlled in five treatments (SWC30, SWC45, SWC60, SWC75 and SWC90) with 30%, 45%, 60%, 75% and 90% soil field capacity, respectively. The study shows that nitrogen accumulation in citrus leaves decreases with scanty or excess SWC. Total free amino acid (y) decreases with increasing SWC(x):y= -0.028 2x+ 12.049; R²= 0.852 4^*; n = 50. There is a negative relation between proline(y) and SWC (x) when SWC is below 75%:y = -0.015 2x+4.224; R² = 0.860 5^*; n = 50. Putrescine (Put) reaches the minimum when SWC is 75%. The change in spermidine (Spd) content follows a parabolic curve with increasing SWC, attaining the maximum at 45% SWC. Maximum of spermine (Spm) occurs at 60% SWC. There is a significant relation between Spd(y) and Put(x): y = 0.240 4x² - 51.337x +2 976.4; R² = 0.858 6^*; n= 50. When SWC drops below 75%, a significant linear relation develops between (Spd+Spm)/Put ratio (y) and SWC(x): y = 0.011 2x+0.173; R² = 0.851 8^*; n = 50. Spd and Spm are the main physiological adjustment factors of polyamine (PAs), which is produced under water stress condition. The degree of the effect of water stress on citrus is determined mainly by (Spd＋Spm)/Put ratio. This ratio is a crucial index for assessing the effects of soil water stress on citrus plants.

Comparison of water use efficiency of Zizyphus jujube and Ulmus pumilain semi-arid zones of the Loess Plateau

JIN Xin-Hong, WANG Bai-Tian, GUO Hong-Yan, WU Jing, LIAO Hang

2009, 17(1): 90-93. doi: 10.3724/SP.J.1011.2009.00090

Abstract(1535) PDF(1231)

Abstract:
In semi-arid regions of the Loess Plateau,Zizyphus jujube and Ulmus pumila samples were selected to study the net photosynthetic rate, transpiration rate and stomatal conductance using LI-6400 portable photosynthesis machine under different controlled soil water contents. Net photosynthetic and transpiration rates were observed under controlled solar radiation intensity through shading to determine water use efficiency. The results show obvious differences in the daily processes of net photosynthetic rate between Z. jujube and U. pumila under different soil water contents. The daily range of change in net photosynthetic rate and water use efficiency for Z. jujube is higher than that for U. pumila. Analysis of continuous daily transpiration rates show that soil water is a major influencing factor of evapotranspiration. Z. jujube has a higher water-consumption rate which decreases at high soil moistures. Therefore U. pumila is more suitable to semi-arid conditions of the Loess Plateau regions than Z. jujube .

Relationship between microclimatic factors and yield of spring tea [Camellia sinensis (L.) O. Kuntze] in Henan Jigongshan Nature Reserve

YU Hong, WANG Xian-Yun, YANG Xiao-Hui, LI Hai-Tao, XIAO Shu-Guang, DU Hua-Tang, HOU Zheng-Hui

2009, 17(1): 94-99. doi: 10.3724/SP.J.1011.2009.00094

Abstract(1071) PDF(1322)

Abstract:
Microclimatic factors have significant effects on yield of spring tea. Regression relations derived from these factors are crucial for the management of spring tea. 18 microclimatic factors and tea outputs were measured during spring tea harvest season. The relationships between yield of spring tea and microclimatic factors were explored. Using the multiple stepwise regression analysis, empirical yield models of spring tea were fitted to microclimatic factors, achieving a high confidence level. These models with different factors show similar and significant regression trends. Eighteen microclimatic factors are categorized into four groups through cluster analysis. Factor analysis indicates that common microclimatic factors of the environment variables are temperature, water and their combination factor, which own bigger load. In conclusion thus, an economic method can be established through measuring fewer microclimatic factors with significant regression models. Such economic methods can achieve similar outcomes with fewer investment, management and processing of spring tea. This can significantly benefit spring tea cultivation and economy.

Effect of pesticides on yield and quality of high quality wheat

PEI Xue-Xia, WANG Jiao-Ai, DANG Jian-You, ZHANG Ding-Yi

2009, 17(1): 100-104. doi: 10.3724/SP.J.1011.2009.00100

Abstract(1259) PDF(1021)

Abstract:
The effect of four pesticides (acetamiprid, imidacloprid, omethoate and beta-cypermethrin) on 1000-kernel weight, yield and quality of three high quality wheat varieties (“Linyou 145”, “Linyou 2069” and “Linyou 2018”) were studied in a field experiment. Results show that pesticides increase 1000-kernel weight and yield of high quality wheat. Omethoate has higher effect than the other pesticides followed by beta-cypermethrin. However, the differences of 1000-kernel weight and yield of high quality wheat under omethoate and beta-cypermethrin treatments are insignificant. Omethoate and beta-cypermethrin increase grain protein content in three high quality wheat varieties. Almost all processing quality indices of strong gluten wheat varieties (“Linyou 145” and “Linyou 2069”) are decreased, with no notable difference from the control. Nutritional and processing quality of moderate gluten wheat (“Linyou 2018”) improves. Acetamiprid has the worst effect on yield and quality of high quality wheat. Pesticides have higher effect on stored protein, gliadin and glutelin in high quality wheat than on soluble protein, albumin and globulin.

Residual dynamics and safely applying technology of pyridaben in vegetable-soybean

GUO Jian-Hui

2009, 17(1): 105-119. doi: 10.3724/SP.J.1011.2009.00105

Abstract(1003) PDF(1046)

Abstract:
In order to monitor pyridaben residue in vegetable-soybean and apply pyridaben scientifically and safely in pest control, the residual content and degradation dynamics of pyridaben in vegetable-soybean were studied by GC-ECD method and field experiment. Meanwhile the safe usage technology demonstration experiments were set up. The established quantitative determination method is simple, accurate and available with 88.8% ~ 94.0% average recoveries of pyridaben residue in vegetable-soybean, 2.2% ~ 4.7% RSD, 0.01 ng LOD and 0.005 mg·kg^-1 LOQ. The original sediment of pyridaben is different for different treatments and the residue degradation dynamics follows the exponential regression equation: ,C=A·e^kt with a correlation coefficient (|r|) range of 0.964 8 ~ 0.995 3 (P < 0.01). The degradation rate of pyridaben in vegetable-soybean is basically consistent in the late seasons of 2004 and 2005 for the different treatments. Pyridaben degradation coefficient (|k|) is 0.181 0 ~ 0.203 9. T_1/2 and T_0.99 of pyridaben are 3.4 ~ 3.8 d and 22.6 ~ 25.4 d respectively. Based on conventional application method, vegetable-soybean is sprayed once or twice (at 7 d intervals) in the demonstration fields with 84.38 g·hm^-2 effective composition of pyridaben. The final residue in vegetable-soybean products is less than 0.1 mg·kg^-1, with average residual contents of 0.054 mg·kg^-1, 0.059 mg·kg^-1 at 18 d after application. The quality of the products meets the minimum requirement level (MRL) of Japan.

Effect of selenium methionine on rumen fermentation and purine derivatives in Simmental steer

LIU Qiang, HUANG Ying-Xiang, WANG Cong, ZHOU Yi, WANG Hao

2009, 17(1): 110-114. doi: 10.3724/SP.J.1011.2009.00110

Abstract(909) PDF(1192)

Abstract:
Four Simmental steers (average BW 420 kg, aged 2.5 years) cannulated in rumen consuming corn straw diet were used in 4×4 Latin square design to evaluate the effects of different selenium methionine on ruminal pH, ammonia, volatile fatty acid, nutrient degradability and purine derivative of urine. Treatments consisted of 0 mg (control), 0.3 mg, 0.6 mg and 0.9 mg supplemental Se (selenium methionine) per kg DM diet. The results show that ruminal pH, volatile fatty acid concentration and actate to propionate ratio are not affected (P> 0.05). Ammonia concentrations in supplemented selenium methionine groups are lower than the control (P< 0.05). Degradability of dry matter, organic matter, and neutral and acid detergent fiber of corn straw, and the degradability of dry matter, organic matter and crude protein of soybean in the 0.6 mg supplemental Se per kg DM are significantly higher than the control group (P< 0.05). Allantoin and purine derivatives in group supplemented with 0.6 mg and 0.9 mg Se per kg are significantly higher than both the control and the 0.3 mg supplemental Se per kg DM (P< 0.05). Supplementation of selenium methionine has passive effect on rumen fermentation. Optimum Se supplementation dose is 0.6 mg·kg^-1.

Primarily study on molecular behavior ecology of rice seedling in response to daily change in sunlight intensity

LIM Wen-Xiong, YU Gao-Jing, XIONG Jun, CHEN Ting

2009, 17(1): 115-119. doi: 10.3724/SP.J.1011.2009.00115

Abstract(1012) PDF(1214)

Abstract:
Commonly cultivated high quality elite rice cultivar “Jiafuzhan” was used to study molecular behavior ecological mechanisms in functional leaves of rice seedlings through investigation on their response to daily changes in sunlight intensity (from 6: 00 to 18:00). The results reveal 7 proteins with regular patterns of daily change in expression abundance and 6 of them are successfully identified and predicted. The proteins are chloroplast photosystem I reaction center subunit II－proteinoid (spot 1 protein), UMP/CMP kinase b (spot 2 protein), OSJNBa0027P08.12 protein (spot 3 protein), putative reductase (spot 4 protein), putative chaperonin (spot 5 protein) and putative sesquiterpene cyclase 1 (spot 6 protein). Expression abundance of all identified proteins drop at mid-day (12:00 ~ 14:00), except for spots 2 and 3 proteins. This implies that the molecular behavior ecological properties are related to deferentially expressed protein abundance in functional rice leaves in response to changes in daylight.

Screening phosphorus-efficient genotypes of rapeseed (Brassica napus)at seedling stage by TOPSIS

LU Kun, ZHONG Wei-Ran, ZHANG Kai, WANG Rui, ZHENG Qin-Yu, LI Jia-Na

2009, 17(1): 120-124. doi: 10.3724/SP.J.1011.2009.00120

Abstract(1085) PDF(893)

Abstract:
Based on preliminary screening on the field, eight rapeseed varieties with different phosphorus efficiencies were adopted in the study. Under phosphate (Pi) deficient and sufficient solution culture conditions, eight indices (root length, shoot fresh weight, root fresh weight, single plant dry weight, root to shoot ratio, phosphorus content, shoot APase activity and root APase activity) that are significantly related to phosphorus efficiency in rapeseed seedling were analyzed. The indices were then ranked using TOPSIS method to precisely screen out real phosphorus-efficient rapeseed genotype. The results show that under Pi deficient and sufficient conditions, rapeseed variety, W17 ranks first and W39 ranks last under TOPSIS ranking, which tallies with filed observation. The rankings for W23 under Pi deficient conditions, and W11 and W31 under Pi sufficient conditions also agree with filed observations. But the ranks for W31 and W290 under Pi deficient conditions and the other 4 varieties under Pi sufficient conditions have an order of difference. More significantly, the ranks for W11, W27 and W288 under Pi deficient conditions exhibit 2 ~ 4 orders of difference with filed observations. It then implies that TOPSIS accurately screens out phosphorus-efficient rapeseed genotype W17 and phosphorus-inefficient rapeseed genotype W39. For the other varieties, TOPSIS ranking has a certain degree of coherence with field observations. This indicates that TOPSIS can improve material screening veracity and is especially suitable for screening extreme varieties.

Effect of phosphorus stress on the pigment and morphology of different maize genotypes

CHEN Jun-Yi, CAI Yi-Lin, XU Li, YANG Zhi-Guo, GAN Xiao-Ling, PAN Ting-Ni

2009, 17(1): 125-129. doi: 10.3724/SP.J.1011.2009.00125

Abstract(889) PDF(1623)

Abstract:
Four maize genotypes were selected to investigate the pigment and morphology of maize genotypes under low and high P dosage. The results show that the ratios of chlorophyll to carotenoid, purpurin and red pigment for four maize genotypes decrease under low P dose. Those of “7922” and “Ye107” are 0.4 ~ 0.8 times those under high P dose, with much higher decrease than in “178” and “*082”. PAL activity and total flavonoid content increase under low P dose. Those in “7922” and “Ye107” under low P dose are 1.5 ~ 2.0 times of those under high P dose, with much higher variation than in “178” and “*082”. Differences in leaf width and leaf fresh weight in “7922” and “Ye107” are significant between low and high P doses. The same is case for leaf chief venation diameter and leaf number in “Ye107”. Leaf width, leaf chief venation diameter, leaf number and leaf fresh weight is decreased under low P dose. A significant difference is observed in leaf pigments and maize leaf shape among the different genotypes. This implies that “7922”and “Ye107” are somehow sensitive to low P stress, while “178” and “*082” are tolerant to low P stress.

Effect of copper stress on photosynthesis of navel orange seedlings

ZHANG Guo-Jun, JIANG Hong, ZHENG Li-Qin, CHEN Juan, QIU Dong-Liang, LIU Xing-Hui

2009, 17(1): 130-134. doi: 10.3724/SP.J.1011.2009.00130

Abstract(1093) PDF(1131)

Abstract:
The hydroponic method was used to study the photosynthetic characteristics of navel orange “No.52” seedlings under Cu stress. The study shows that chlorophyll (Chl.) content under 0.1 mmol·L^-1 of Cu increases significantly, but decreases under 5 mmol·L^-1, 20 mmol·L^-1 and 40 mmol·L^-1 of Cu. Carotenoid content decreases with increasing Cu concentration. Net photosynthetic rate and light saturation point reduces under Cu stress as Cu concentration exceeds 5 mmol·L^-1. 0.1 mmol·L^-1 of Cu improves, but 5 mmol·L^-1 and 20 mmol·L^-1 of Cu decrease transpiration rate and stomatal conductance of orange. These parameters do not change significantly under 40 mmol·L^-1 of Cu. At the same time, high Cu concentration (5 mmol·L^-1, 20 mmol·L^-1 and 40 mmol·L^-1) restricts photoreduction activity. The findings indicate that lower Cu concentration improves photosynthesis while high Cu concentration inhabits it.

Effect of Cu stress on photosynthesis and nutrient absorption of grafted and ungrafted cucumber seedling

ZHANG Zi-Kun, LIU Zuo-Xin, ZHANG Ying, SHU Qiao-Sheng

2009, 17(1): 135-139. doi: 10.3724/SP.J.1011.2009.00135

Abstract(1438) PDF(1418)

Abstract:
Under water culture, this paper researched into the effect of copper stress on photosynthesis and nutrient absorption of grafted (Cucumis sativus L. “Xintaimici” / Cucurbita ficifolia) and ungrated cucumber. Under 6 days of copper stress, there is significant depression in the contents of chlorophyll, carotenoid, nutrient(N, K, Ca, and Mg), and in net photosynthetic rate and stomatal conductance in both grafted and ungrafted cucumber seedling leaves. An obvious increase in electrolyte leakage is also observed. Though intercellular CO₂ concentration depresses with increase in Cu concentration, there exists no significant correlation among the treatments. The contents of chlorophyll, carotenoid and nutrient (N, K, Ca, and Mg) and the net photosynthetic rate of grafted cucumber seedling leaves are significantly higher than those in ungrafted cucumber plants. On the other hand, percent electrolyte leakage is significantly lower in grafted than that in ungrafted cucumber plants. Copper content in grafted cucumber seedling leaves is significantly lower than that in ungrafted seedling leaves. This implies that grafted cucumber plants have the strong capacity for inhibiting Cu²⁺ accumulation in leaves which alleviates copper poison.

Effect of UV-B on growth and development and secondary metabolism of flue-cured tobacco

HUANG Yong, ZHOU Ji-Heng, ZHENG Ming, YANG Hong-Qi, ZHANG Ning-Yuan

2009, 17(1): 140-144. doi: 10.3724/SP.J.1011.2009.00140

Abstract(1500) PDF(1759)

Abstract:
UV-B was used to radiate flue-cured tobacco “K326”. Then the effects of different modes and intensities of UV-B radiant on tobacco growth, photosynthetic physiology, pigment, polyphenols, sugar and nicotine contents studied. Results show that tobacco “K326” stem dwarfs and thickens. Also leaf area and net photosynthetic rate moderately decline when flue-cured tobacco “K326” is treated with UV-B radiation. Chlorophyll, sugar and nicotine contents decrease with increasing of UV-B radiant intensity. Chlorophyll content is enhanced by low UV-B radiant intensity. The content of polyphenol in relation to plant stress resistance increases significantly, positively correlated with treatment time and radiant intensity. Pretreatment of rational intensity of UV-B radiant can increase chlorophyll, total carotenoids, and total sugar contents.

Chemical forms and transformations of Pb and Cd in granitic latosol of Hainan Island

TANG Wen-Hao, YUE Ping, CHEN Heng-Yu

2009, 17(1): 145-149. doi: 10.3724/SP.J.1011.2009.00145

Abstract(858) PDF(1169)

Abstract:
The transformation processes of Pb and Cd in granitic latosol of Hainan Island were characterized and the effect of exotic heavy metals (Pb and Cd) and three soil amendments on their chemical forms in the soil studied. Results show that the major fractions of Pb in the original tested soils are in bond and residual forms. Lower content of the available form of Pb indicates low environmental risk. The percentage of the different forms of Pb is in the order of: residual > organic > Fe-Mn oxide > carbonate > exchangeable > water soluble form. The major fractions of Cd in the original tested soils are in the form of Fe-Mn oxide bond and carbonate bond. The higher content of exchangeable Cd indicates high environmental risk. The percentage of the different forms of Cd is in the order of: Fe-Mn oxide > carbonate > exchangeable > organic > residual > water soluble form. With increasing loads of exotic heavy metals (Pb and Cd) in the soils, the tendencies are that Fe-Mn oxide Pb > residual Pb > organic Pb > carbonate Pb > exchangeable Pb > water soluble Pb, and that exchangeable Cd > Fe-Mn oxide Cd > carbonate Cd > residual Cd > organic Cd > water soluble Cd. The application of three soil amendments (calcium superphosphate, lime and sodium sulphide) significantly reduces the percentage of Pb and Cd in water soluble and exchangeable forms; and organic Pb, carbonate Pb and Fe-Mn oxide Pb decline. However, residuals of Pb, carbonate-Cd, Fe-Mn oxide bound Cd and organic Cd increase. Cd residual is basically stable.

Response of farmland with different natural quality to farm field input

CHEN Ya-Heng, LIU Hui-Ling, LI He-Jing, HUO Xi-Liang, XU Hao

2009, 17(1): 150-154. doi: 10.3724/SP.J.1011.2009.00150

Abstract(1262) PDF(1061)

Abstract:
To analyze the effect of field input on grain yield and economic benefit of farmlands, we used wheat-corn double crop-ping fields in northern Taihang Mountain Plain region of central Hebei to analyze the degree of response to input from farmland quality on basis of factor combination, hypothesis testing, regression analysis and agricultural land grade. The results suggest that grain yield can be improved by scientifically and reasonably increasing field input or using a combination of factors at low input. High yield on farmlands with poor natural conditions can be achieved through scientific and reasonable input. The optimal value of field input is within the interval between the maximum input-output benefit and maximum grain yield. Reasonably adjusted input based on differences in the influence of natural factors on grain yield and different factor combinations can increase yield significantly.

Spatial variation in agro-ecosystem based on county level emergy analysis in Fujian Province

HU Xiao-Hui, HUANG Min-Sheng, ZHANG Hong, REN Chan-Juan

2009, 17(1): 155-162. doi: 10.3724/SP.J.1011.2009.00155

Abstract(1382) PDF(1637)

Abstract:
This paper used emergy analysis method at unit county scale to study the spatial variation in agro-ecosystem in Fujian Province. The paper established 13 emergy indicators grouped into 4 levels of agro-ecological economic systems, and selected major emergy evaluation indices by component analysis. Indices and ranks were created for agro-ecosystem development at different aspects for the 67 counties using GIS platform. The result shows clear spatial variations in the agro-ecosystems. These variations are driven by geographical and hypsographical factors. Low-lying coastal counties / cities have absolute advantage in agro-economic development and farmers’ living standards. These advantages are, however weak and can therefore be hardly sustainable. Some inland mountainous counties / cites have obvious regional comparative advantage in natural agro-environmental condition and sustainable development capacity. Based on the results, these are spatially classified into 4 groups. The study provides scientific bases for regional agro-ecological planning and management decisions at all ranks.

Optimized eco-productive paradigm of hilly landscapes in the southern piedmont region of Daxing’anling Mountain—A case study of Linxi County, Inner Mongolia

LI Xin-Yu, TANG Hai-Ping, ZHANG Xin-Shi, SUN Li

2009, 17(1): 163-168. doi: 10.3724/SP.J.1011.2009.00163

Abstract(1283) PDF(1400)

Abstract:
On the basis of landscape ecology theory, the outstanding characteristics of the North Farming-pastoral Zone are the landscape of extensively cultivated farmland and villages scattered across grassland (and sometimes forestland) landscapes in China. Optimized eco-productive paradigm of the North Farming-pastoral Zone attempts to build optimized land-use and spatial distribution patterns. As a case study, hilly ecosystems in Linxi County in Inner Mongolia are divided into three agricultural and eco-economic regions with different integral functions based the characteristics of the eco-environment and social economy synthetically. Based on demand for land and optimized farmer production development modes in three regions, optimized eco-management land use pattern paradigm is proposed for Linxi hilly-mountains ecosystem. This is based on optimization principles and spatial land use allocation restrictions. River valley plain agricultural and eco-economic regions should be developed for intensive-efficient agricultural production zones. Low hilly-mountain agricultural and eco-economic regions like ecotones with production and other ecological sites should be positioned in the husbandry-food development mode. Mid-mountains ecosystem should be put in fruit-ecotourism and habitat-conservation areas and farmers emigrated to river valley plains and low hilly-mountain regions.

Depopulation of rural areas under the backdrop of urbanization— A case study of Kangbao County, Northwest of Hebei Province

PEI Hong-Wei, CHANG Chun-Ping, HE Wen-Hui, SHEN Yan-Jun

2009, 17(1): 169-173. doi: 10.3724/SP.J.1011.2009.00169

Abstract(1561) PDF(1505)

Abstract:
To understand the issues and driving factors of rural depopulation (a universal phenomenon in the rural areas of every nation under the backdrop of urbanization), we surveyed 19 villages in Kangbao County, Hebei Province. The villages are in the farming pastoral interlocks of North China where the ecology is fragile and the economic backward. The number of idle houses and the degree of damaged house were quantitatively analyzed. The survey shows that the proportion of idle brick houses to total brick houses is 0.360, and that of earthen houses to total usable earthen house is 0.254. That for dilapidated houses to total houses is 0.350. Depopulation of the rural villages in the farming pastoral interlocks of North China has the following characteristics: The extent of depopulation is in direct correlation with farmer income level. Low and slow economic development is the fundamental cause of depopulation in the area. Labor loss has resulted in severe dilapidation of village landscape and resource waste. Depopulation has severely retarded normal orders of rural production and life.

Physical influencing factors of groundwater depth in Hotan Oasis

LIU Min, HUANG Ling-Mei, SHEN Bing, SHEN Yan-Jun

2009, 17(1): 174-177. doi: 10.3724/SP.J.1011.2009.00174

Abstract(1435) PDF(1556)

Abstract:
The influences of natural factors on groundwater depth in Hotan Oasis were analyzed by grey relational analysis and multiple linear regression models set up to test the precision of the analysis. The results show that temperature and evaporation are the most important influencing factors of groundwater depth. Groundwater depth sinks deeper with increasing temperature and evaporation. Runoff recharges groundwater and is the second important factor. Groundwater depth gets shallower with increasing runoff and groundwater response lags by one to two months. The influence of wind speed, water temperature or humidity on groundwater depth is relatively low. There is no significant correlation between precipitation and groundwater depth. The groundwater depth regression models have high precision with confidence levels above α = 0.01.

Analysis of drought monitoring on Hainan Island from standardized precipitation index

LI Wei-Guang, CHEN Hui-Lin, ZHU Nai-Hai, CHEN Zhen-Li

2009, 17(1): 178-182. doi: 10.3724/SP.J.1011.2009.00178

Abstract(1604) PDF(1282)

Abstract:
The feasibility of simulating precipitation on different temporal scales on Hainan Island using Γ Distribution model was reviewed in this paper. Drought conditions on the island were determined using Standardized Precipitation Index (SPI). The results show that the combination use of SPI with different time scales can be useful in identifying the onset, duration and intensity of different degrees of drought during dry and rainy seasons. It is therefore suggested that 6 and 12 months SPI in winter-spring season and 1 or 3 months SPI in summer-fall season can be used to monitor drought conditions on Hainan Island.

Fractal features of scenic spatial construction in Wuyishan World Natural and Culture Heritage

ZHANG Chun-Ying, HONG Wei, WU Cheng-Zhen, HONG Tao, CHEN Can, LI Jian, WANG Ying-Zi

2009, 17(1): 183-188. doi: 10.3724/SP.J.1011.2009.00183

Abstract(1247) PDF(1072)

Abstract:
By using box dimension, information dimension and correlation dimension, fractal features of Wuyishan Natural and Culture Heritage were studied at a multi-dynamic scale. At the A sampling scale (with 1.474 box dimension, 1.415 information dimension, and 1.048 correlation dimension ), the derived correlation coefficients (R) are 0.994, 0.999 and 0.969. At the B sampling scale, box dimension ranges from B₁ to B₄, the correlation coefficient ranges from 0.825 ~ 1.200, R values are all above 0.961. The range of information dimension is 0.919 ~ 1.302 with R values above 0.964. Correlation dimension range is 0.822 ~ 1.364 with R values above 0.941. At the C sampling scale, range of box dimension is C₁ ~ C₁₆ (excluding plots with spot quantity between 0 ~ 1), the correlation coefficient is 0.175 ~ 0.931 with R values above 0.775. That of information dimension is 0.200 ~ 1.039 with R values above 0.771. Correlation dimension range is 0.506 ~ 1.929 with R values above 0.704. It is thus concluded that: the scenery system of Wuyishan Natural and Culture Heritage has obvious fractal characteristics. Furthermore, the fractal dimensions are sensitive to sampling scale.

Continuous cropping obstacle and allelopathic autotoxicity of medicinal plants

ZHANG Zhong-Yi, LIN Wen-Xiong

2009, 17(1): 189-196. doi: 10.3724/SP.J.1011.2009.00189

Abstract(3726) PDF(5526)

Abstract:
In this paper, the concept, mechanism and action mode of allelopathic autotoxicity of medicinal plants were discussed. The study identifies that the basic reason for the continuous cropping obstacles and allelopathic autotoxicity of medicinal plant is the homology of autotoxic-allelochemicals and pharmaceutical active substances.Accordingly, the relationship between the causes of the obstacles and the autotoxicity of allelochemicals in medicinal plants are also analyzed. Comprehensive agronomic methods based on rhizospheric soil microflora systems research using DGGE, T-RFLP and other related techniques are proposed. This reduces the inhibiting effect of continuous cropping obstacles and allelopathic autotoxicity

Function of microorganism in bioremediation of eutrophic water

ZHENG Huan-Chun, ZHOU Qing

2009, 17(1): 197-202. doi: 10.3724/SP.J.1011.2009.00197

Abstract(1875) PDF(3326)

Abstract:
The cause and discrimination standard of water eutrophication are introduced in this work. Furthermore, the main microorganisms involved in nitrogen and phosphorus removal during eutrophic water bioremediation are listed. This paper also analyzes the function of different microorganisms in water bioremediation of substance cycle. Substance cycle here includes carbon cycle, nitrogen cycle, phosphorus cycle and sulfur cycle. It reveals the function of microorganisms in water bioremediation. Finally, advances in microbial remediation of water and microbial preparation are briefly summarized. Some concluding comments are stated for future research on the role of microorganisms in bioremediation.

2009 Vol. 17, No. 1