• Authors:
    • Tang, L.
    • Zheng, Y.
    • Ren, J.
    • Wang, Y.
  • Source: Journal of Yunnan Agricultural University
  • Volume: 26
  • Issue: 6
  • Year: 2011
  • Summary: Through field experiment, we studied the dynamics change of phosphorus in rhizosphere and bulk soil under wheat and faba bean intercropping and wheat monoculture, and the effects rhizosphere and bulk soil phosphorus under wheat and faba bean intercropping and wheat monoculture. The results showed that there was consistency in each growth date of rhizosphere soil phosphorus under wheat intercropping and monoculture, the bulk soil phosphorus content was highest in filling under wheat monoculture, and reached the highest in tilling under wheat intercropping. In wheat and faba bean intercropping, the rhizosphere soil phosphorus content of wheat was increasing from tilling stage to filling stage, and the rhizosphere and bulk soil phosphorus content in maturity was dramatically bringing down. The rhizosphere soil phosphorus contents of wheat increased by 6.81%, 8.71% and 12.95% in jointing, tilling and filling stages, respectively, and reduced by 21.11% in maturity stage.
  • Authors:
    • Yang, L.
    • Yin, S.
    • Xia, L.
    • Yu, Y.
    • Wu, D.
  • Source: PEDOSPHERE
  • Volume: 21
  • Issue: 6
  • Year: 2011
  • Summary: In the Three Gorges Area of China, soil erosion and the resultant non-point source pollution and ecological degradation have endangered agricultural ecosystems and fresh water reservoirs. Although efforts have been undertaken to reduce soil and water losses from slope land used for citrus production, information on the effects of management practices on soil fertility indices is either limited or nonexistent. This study was conducted to compare the effects of 10 years of various management practices, citrus intercropped with white clover (WC), citrus mulched with straw (SM), citrus intercropped with contour hedgerows (CH), citrus orchard land with impermeable membrane (IM), and citrus intercropped with wheat ( Triticum aestivum) and peanut ( Arachris hypogaea) (WP), as treatments on soil fertility indices with that of the conventional citrus management (CM). Results showed that the soil organic carbon, total and available nitrogen, available potassium, and water-stable aggregate (>0.25 mm) contents at the 0-5 cm depth were higher for the WC and SM treatments than the CM treatment. There was also spatial variation in soil fertility along slopes of the WC and SM treatments. The soil total and available nitrogen, phosphorus, and potassium, and water-stable aggregate (>0.25 mm) contents at both the 0-5 and 5-20 cm depths were higher for the CH and IM treatments than the CM treatment. The average soil available nitrogen and available potassium contents were higher for the WP treatment than the CM treatment, but the WP treatment had little effect on the soil organic carbon, total nitrogen, and water-stable aggregate (>0.25 mm) contents. These suggested that white clover intercropping and straw mulching were the most effective approaches to improve soil fertility in citrus orchard land of the Three Gorges area.
  • Authors:
    • Xu, L.
    • Zhang, P.
    • Guo, W.
    • Liu, R.
    • Yang, C.
  • Source: Jiangsu Journal of Agricultural Sciences
  • Volume: 27
  • Issue: 5
  • Year: 2011
  • Summary: To investigate the effect of wheat-cotton double cropping system on cotton, planting pattern experiments in field were conducted in 2009-2010, with wheat-cotton intercropping system as control. The indexes of development characteristics and yield component of cotton were analyzed. The results were showed as follows. In wheat-cotton intercropping treatment, the development process was earlier, and the forming of fruit node and boll was longer and more than those of cotton transplanted after wheat harvest. The later autumn boll percent was only 3.2%-4.7% and the rate of blossom before frost was 88.6%-95.7%. The cotton in intercropping system also had high biomass and harmonious relationship between vegetative growth and reproduction. For cotton transplanted after wheat harvest treatments, the dry matters were low and pre-summer bolls were few. For cotton with substrate or nutrition treatment, the forming of fruit node and boll was later and less than those of cotton with intercropping treatment, the late autumn boll percents were 11.8%-20.8%, and the rate of blossom before frost was 77.2%-90.7%. The seed yield of cotton with substrate treatment was lower than that of cotton with intercropping treatment, but higher than that of cotton with nutrition treatment. For direct seeding cotton of medium-matured variety after wheat harvest, the reproductive growth was later and weaker. The forming of fruit node and boll was later and had no obvious peak, which easily caused invalid growth at later stage. The late autumn boll percent was 24.5%-34.0% and the rate of blossom before frost and seed yield were low. For direct seeding cotton of early-matured variety after wheat harvest, the transforming growth from vegetative to reproductive growth was earlier. The forming of fruit node and boll was concentrated with higher peak value and the total dry matter in reproductive organ was higher. The late autumn boll percent was only 3.3% and the rate of blossom before frost was 88.0%. The seed yield was equal to that of cotton transplanted after wheat harvest. As a result, the yield of cotton in intercropping system was higher and more stable, and that of transplanted cotton might be potential, while that of direct seedling cotton depended on the variety characteristics.
  • Authors:
    • Shan, Y.
    • Mu, M.
    • Han, S.
    • Zhang, Y.
    • Yu, K.
  • Source: Zhongguo Shengtai Nongye Xuebao / Chinese Journal of Eco-Agriculture
  • Volume: 19
  • Issue: 4
  • Year: 2011
  • Summary: Yantai (a city in Shandong Province) is a strong base for winter wheat-maize double-copping system. A previous double-copping system experiment involving single-stem late wheat intercropped with late-maturing maize in Longkou (a county of Yantai City) yielded 22 770 kg.hm -2. Other studies have reported grain yields excess of 22 500 kg.hm -2 in North China. For various reasons, however, replicating these experiments at field scales has not been feasible. As one of the first institutions to develop super-high-yield experiments, the Grain and Food Safety Research Center of China Agricultural University was founded in July 2004 in Yantai City, Shandong Province, at where we conducted a 3-year experiment on high-yield technology system of double-cropping system. Based on weather analysis in Longkou and Laizhou Counties of Yantai City, where super-high-yield experiments were first conducted, this paper put forward a new research direction that makes rational use of the abundant light, heat and species resources in Yantai for high-yield wheat-maize double copping system. The strategy delayed the sowing time of wheat to get the effective temperature (≥16degreesC) for maize to fully exploit yield potential of longer growth period maize varieties. Two modes of double-cropping system cultivation techniques with suitable improved varieties were designed and selected. Based on the design, Longkou was best fitted for a double-copping system of mid-late wheat intercropped with mid-late maturing maize with Oct. 10 -> Oct. 10 crop-rotation periods. Laizhou, on the other hand, was best fitted for double-copping system of single-stem late wheat variety mixed with mid-late maturing maize with Oct. 15 -> Oct. 15 crop-rotation periods. Furthermore, the corresponding suitable varieties were incorporated into the experiments. The results of the double-copping system experiments were as follows: Longkou was suitable for the mid-late wheat "Liangxing 99" intercropped the mid-late maturing maize "Jinhai No. 5" of double-copping system with Oct. 10 -> Oct. 10 crop-rotation period. Laizhou was suitable for directly sowed single-stem late wheat "Liangxing 99" mixed with the mid-late maturing maize "Jinhai 607" of double copping with Oct. 15 -> Oct. 15 crop-rotation period. The results of three-year high-yield experiments in Laizhou and Longkou showed that yields were above 21 000 kg.hm -2 per year. Yields for the last year reached the expected target of 22 500 kg.hm -2. Yields for the area of 0.074 hm 2 reached 24 792.45 kg.hm -2 for the two seasons. The study showed that wheat-maize double-cropping system technology that made full use of light, heat and variety resources was more rational for Yantai, which brought local potential productivity to full realization.
  • Authors:
    • Smith, D.
    • Yang, W.
    • Chen, X.
    • Liu, W.
    • Zhang, J.
  • Source: African Journal of Agricultural Research
  • Volume: 6
  • Issue: 27
  • Year: 2011
  • Summary: Production practice shows shaded soybean in wheat-maize-soybean; relay strip intercropping system has better tolerance to drought as compared with sole cropping soybean. Our researches are to understand the reasons through non-hydraulic root signals (nHRS), yield and the relationships among them. Pot experiments were conducted with two soybean cultivars, under shade of maize (LI) and normal irradiance (HI). nHRS were traced during manipulative progressive soil drying period at branching stage under good soil conditions (HW), water stress treatment (LW), in 2010. Well-watered (WW), light drought (LD), moderate drought (MD) and severe drought (SD) were applied in 2009. In response to soil drying, nHRS appeared earlier in Gongxuan No.1 (GX) than Gongqiudou 05-8 (GQ) under two irradiance treatments, but it disappeared earlier for GX than GQ under normal irradiance. GX exhibited a wider average soil water content threshold range (TR) of nHRS under low irradiance. Drought stress significantly decreased the shoot dry mass, root mass and grain yield (P
  • Authors:
    • Li, Z.
    • Zhang, M.
    • Sun, X.
    • Song, X.
    • Zhao, Q.
  • Source: Plant Nutrition and Fertilizer Science
  • Volume: 17
  • Issue: 6
  • Year: 2011
  • Summary: Soil microorganism quantities and enzyme activities were studied in fields under wheat-cotton and garlic-cotton intercropping systems. Compared with cotton monoculture, both intercropping systems proved to be conducive to the proliferation of soil bacteria and actinomycetales and inhibited proliferation of fungi, the effects of the garlic-cotton intercropping system being more pronounced than those of the wheat-cotton intercropping system. Throughout the growth period of the cotton crop, soil urease activity and sucrase activity in 0-20 cm soil layer in the garlic-cotton intercropping system were significantly higher than in cotton monoculture, and the alkaline phosphatase activity in the garlic-cotton intercropping system was significantly higher than that in the cotton monoculture except at the flowering and blooming stages of cotton. The catalase activities in the garlic-cotton intercropping system at the seedling stage and boll-opening stage were significantly higher than in cotton monoculture. In the wheat-cotton intercropping system, soil urease activity and sucrase activity in the 0-20 cm soil layer at the seedling, flowering and boll stages of cotton were higher than in cotton monoculture, alkaline phosphatase activity at the bud stage was significantly higher than in cotton monoculture, and catalase activity at the seedling and boll opening stages was significantly higher than in cotton monoculture. In conclusion, the garlic-cotton and the wheat-cotton intercropping systems can increase the quantities of soil bacteria and actinomycetales, thus effectively suppressing the occurrence of succession cropping obstacles in cotton fields, and they also increase the activities of soil-related enzymes, which is good for creating healthy soil in cotton fields.
  • Authors:
    • Du, X.
    • Zhang, D.
    • Dong, M.
  • Source: Acta Phytophylacica Sinica
  • Volume: 38
  • Issue: 4
  • Year: 2011
  • Summary: Aphids are primary pests of peach in early organic field. In order to know the relationship between aphids and their natural enemies and the ecological management, we design three ecological control mode, which are the treatment of planting garlic+mulch plastic film, the treatment of planting 100% alfalfa and the treatment of planting 70% alfalfa+30% Lagopsis supine. We investigate the insect community, analyse the natural enemies of aphids and the effect of ecological management. The results showed the main natural enemies of Myzus persicae (Sulzer), Hyalopterus amygdali (Blanchard) and Tuberocephalus momonis (Matsumura) were Propylea japonica (Thunberg), Orius sauteri (Poppius) and Coccinella septempunctata (Linnaeusaeus). There was negative relationship between aphids and natural enemy/pest index. The natural enemy/pest index and evenness of natural enemies was significantly higher and the abundance of M. persicae, H. amygdali and T. momonis were significantly lower in the treatment of planting 100% alfalfa and in the treatment of planting 70% alfalfa +30% L. supina than those of control treatment. It is benefit to control green peach aphids with planting 100% alfalfa and it is benefit to control M. persicae, H. amygdali and T. momonis with planting 70% alfalfa+30% L. supina.
  • Authors:
    • Li, Y.
    • Zu, Y.
    • Wu, B.
    • An, T.
    • Zhan, F.
    • Yang, J.
    • Fu, Z.
  • Source: Research of Environmental Sciences
  • Volume: 24
  • Issue: 11
  • Year: 2011
  • Summary: In order to explore the effects of different planting patterns for the effective control of farmland runoff contamination, loss of TN, TP, COD Cr and SS under different planting patterns were analyzed with field plot experiments. The results showed that the surface runoff, loss of TN, TP, COD Cr and SS under a mono-cropping system were higher than under a maize and vegetables intercropping system. The surface runoff, loss of TN, TP, COD Cr and SS could be reduced using a maize and vegetables intercropping system. The maize || cauliflower/potato intercropping pattern was the most effective. Comparing with cauliflower/potato mono-cropping system, its reduction percentages of surface runoff, TN, TP, COD Cr and SS were 79.59%, 86.87%, 84.23%, 91.41% and 82.46%, respectively.
  • Authors:
    • Han, T.
    • Huang, Z.
  • Source: Guizhou Agricultural Sciences
  • Issue: 9
  • Year: 2011
  • Summary: Beiqing 7, a new hulles barley variety with characteristics of early maturity, high yield, 13% crude protein content, good agronomic characters, strong resistance to lodging and disease and wide adaptability, was bred from MDYT (female parent) * 245 (male parent) combination by systematic breeding method for 13 years and approved by Qinghai Crops Variety Examination Committee to improve breeding level of hulless barley, culture new hulless barley varieties with quality and high yield for promoting development of hulless barley industrialization in Qinghai province. The yield of Beiqing 7 in the production tests was 10% higher than Beiqing 6 (a current commercial variety). Beiqing 7 can be cultivated in dryland areas with 0degreesC in Tibet plateau.
  • Authors:
    • Vasseur, L.
    • Lotz, L.
    • You, M.
    • Lai, R.
  • Source: Agronomy Journal
  • Volume: 103
  • Issue: 3
  • Year: 2011
  • Summary: The green peach aphid, Myzus persicae (Sulzer), is an insect pest that causes extensive damage to tobacco ( Nicotiana tabacum L.) in China. Field trials were conducted in 2008 and 2009 at Longyan in the Fujian Province (China) to evaluate the effects of garlic ( Allium sativum L.) as a deterrent to green peach aphids and other arthropods when intercropped in flue-cured tobacco fields. This study demonstrated that green peach aphids were affected by intercropping garlic in tobacco fields during the 2 yr studied. The appearance of green peach aphids in intercropped tobacco fields was delayed for approximately 7 d by the presence of garlic. Aphid abundance was reduced by 100% in intercropped fields compared with monocultures, especially when populations peaked (34.7-39.0% in 2008 and 42.0-47.2% in 2009). Other arthropod populations were not negatively affected by intercropping garlic. Species richness, diversity, and stability of the arthropod communities increased and the dominance concentration index decreased in the intercropped garlic fields. The tobacco mosaic viruses (cucumber mosaic virus, potato virus Y, tobacco etch virus, and tobacco ring-spot virus) transmitted by green peach aphids were decreased by 9.6 to 42.4% in 2008 and by 22.1 to 27.9% in 2009 by intercropping garlic in flue-cured tobacco fields. The net benefits of cropping flue-cured tobacco were also increased by 52.1 to 80.2% by intercropping garlic in the tobacco fields. Therefore, intercropping tobacco with garlic may be useful in deterring green peach aphids and in stabilizing arthropod communities in tobacco.