• Authors:
    • Wang, J.
    • Jolliffe, P.
    • Kimmins, J.
    • Cao, F.
  • Source: Agroforestry Systems
  • Volume: 79
  • Issue: 3
  • Year: 2010
  • Summary: Ginkgo ( Ginkgo biloba L.) is a multi-value deciduous tree species grown for the production of nuts, timber and foliage for medicinal products. Understanding the ecological and biological basis for Ginkgo agroforestry systems is essential for the design of optimum Ginkgo-crop species combinations. We established two greenhouse replacement series to examine interactions between Ginkgo and wheat ( Triticum aestivum L.); and Ginkgo and broad bean ( Vicia faba L.). The results showed that crop species were more competitive than Ginkgo at low Ginkgo density, but less competitive than Ginkgo at high Ginkgo density. Ginkgo: wheat ratio 5:1 and Ginkgo: broad bean ratio 5:1 had relative yield total (RYT) and relative land output (RLO) values of more than one and the largest total land output (TLO) values in respective mixtures. Therefore, these two ratios might be considered optimum Ginkgo: crop ratio for enhancing the combined biomass of the Ginkgo and crop in respective mixtures. Broad bean and wheat were more competitive than Ginkgo, which was less affected by wheat than by broad bean. However, there were compensatory interactions between Ginkgo and wheat, and Ginkgo and broad bean. There was significant belowground competition for soil N between Ginkgo and the two crop species in the Ginkgo/crop mixtures. The two mixtures outperformed monocultures of the individual species when comparing the mixtures with the crop monoculture system.
  • Authors:
    • Chen, L.
    • Sun, Q.
    • Li, H.
    • Fang, S.
  • Source: Agroforestry Systems
  • Volume: 79
  • Issue: 2
  • Year: 2010
  • Summary: The importance of agroforestry systems in CO 2 mitigation has become recognized worldwide in recent years. However, little is known about carbon (C) sequestered in poplar intercropping systems. This study aims compare the effects of three poplar intercropping designs (configuration A: 250 trees ha -1; configuration B: 167 trees ha -1 and configuration C: 94 trees ha -1) and two intercropping systems (wheat-maize cropping system and wheat-soybean cropping system) on biomass production and C stocks in poplar intercropping systems. The experiment was conducted at Suqian Ecological Demonstration Garden of fast-growing poplar plantations in northwestern Jiangsu, China. A significant difference in C concentration was observed among the poplar biomass components investigated ( P≤0.05), with the highest value in stemwood and the lowest in fine roots, ranging from 459.9 to 526.7 g kg -1. There was also a significant difference in C concentration among the different crop components ( P≤0.05), and the highest concentration was observed in the maize ear. Over the 5-year period, the total poplar biomass increased with increasing tree density, ranging from 8.77 to 15.12 tonnes ha -1, while annual biomass production among the crops ranged from 4.69 to 16.58 tonnes ha -1 in the three configurations. Overall, total C stock in the poplar intercropping system was affected by configurations and cropping systems, and configuration A obtained the largest total C stock, reaching 16.7 tonnes C ha -1 for the wheat-soybean cropping system and 18.9 tonnes C ha -1 for the wheat-maize cropping system. Results from this case study suggest that configuration A was a relative optimum poplar intercropping system both for economic benefits and for C sequestration.
  • Authors:
    • Miao, G.
    • Gao, Z.
    • Guo, C.
  • Source: Acta Agronomica Sinica
  • Volume: 36
  • Issue: 4
  • Year: 2010
  • Summary: Shading post flowering, caused by cloudy weather and the surrounding protective trees, often occurs in some wheat ( Triticum aestivum L.) area in north China. In general, wheat yield is negatively influenced by shading post flowering, but the effect on grain quality is reported discrepantly. This study aimed at disclosing the effects of post-flowering shading on photosynthesis of leaf and yield and quality of grain in wheat, accordingly, giving suggestions to wheat production. Three treatments were designed with shading of 20%, 50%, and 80% for 30 d, respectively. The normal condition was taken as the control. The results showed that shading treatments had significant influences on photosynthetic characteristics of flag leaf. The shading treatments increased the number of sterile spikelet and reduced the grain weight per spike and the 1000-grain weight. As a result, the grain yield of the three shading treatments significantly decreased by 27.6%, 49.0%, and 60.2% compared with the control. In the shading treatments, the contents of the chlorophylls a and b increased, whereas the ratio of chlorophyll a to chlorophyll b decreased. Moreover, the net photosynthetic rate, the stomatal conductance, and the transpiration rate were also significantly reduced, but the intercellular CO 2 concentration was promoted. The shading depression on net photosynthetic rate became smaller in the process of grain filling, with the largest effect at early stage of grain filling and the smallest effect at late stage of grain filling stage. The contents of protein, wet gluten, glutenin, gliadin and the ratio of glutenin to gliadin in grains increased significantly with the increase of shading. The shading influence on glutenin was greater than that on gliadin. Although the shading treatments decreased grain yield obviously, it raised some quality parameters, such as extensibility, development time, stability time, and water absorption of dough. The responses of yield and quality of wheat grain to shading were different because of the discrepant synthesis mechanisms of starch and protein under weak light condition. In wheat protective areas, yield is a priority factor and the tree-wheat intercropping mode should be avoided.
  • Authors:
    • Li, L.
    • Chen, W.
    • Sun, J.
    • Hu, H.
    • Yu, C.
    • Li, Q.
  • Source: Plant Nutrition and Fertilizer Science
  • Volume: 16
  • Issue: 4
  • Year: 2010
  • Summary: In a field micro-plot experiment in China of three intercropping systems (barley/maize, wheat/maize, faba bean/maize) and their corresponding sole cropping systems, nitrogen (N) was applied at N 0 and 225 kg/ha, and N absorption and use efficiency and its accumulation on the soil profile were investigated. The competitive ability of crops for nutrients was closely related to the concentration and accumulation of mineral nitrogen in the root zone of the plants. Accumulation of mineral nitrogen under barley or wheat strips intercropped with maize decreased by 203-282 or 107-171 kg/ha in the 0-100 cm soil profile, respectively, compared with faba bean intercropped with maize. Accumulation of mineral nitrogen under maize strips intercropped with barley or wheat was reduced by 93-120 or 56-87 kg/ha compared with maize intercropped with faba bean, respectively. Crop types, interspecific competition and soil condition affected accumulation of mineral nitrogen in the soil profile. Interspecific interaction increased nitrogen recovery efficiency for barley and wheat intercropped with maize and decreased that for maize intercropped with barley and wheat. Nitrogen use efficiency was the highest in the no-N treatment for competitive intercropping systems (barley/maize or wheat/maize). Nitrogen harvest index was reduced in barley and wheat with N fertilizer application, but increased in maize and not changed in faba bean. It is concluded that competition between crops, soil fertility status, fertilizer rate and cultural measures should be considered carefully in order to achieve intercropping advantage when associated crops are chosen. Complement systems of legumes/cereals are recommended for low soil fertility and competitive systems of cereals/cereals for high soil fertility.
  • Authors:
    • Liu Qian
    • Zhang TingWei
    • Liu ChangZhong
  • Source: Guizhou Agricultural Sciences
  • Issue: 6
  • Year: 2010
  • Summary: The results from studying the effect of inter-cropping of wheat with different crops on occurrence quantity of wheat aphid at flowering and filling stage of wheat showed that the aphid occurrence quantity of inter-cropping of wheat with maize or Helianthus annuus or soybean significantly lower than wheat single cultivation, there was significantly difference in aphid occurrence quantity among three inter-cropping patterns and the aphid occurrence quantity of wheat/maize inter-cropping pattern was the lowest, followed by wheat/ Helianthus annuus inter-cropping pattern.
  • Authors:
    • Duan, Z.
    • Dong, Y.
    • Tang, L.
    • Zheng, Y.
    • Zhao, P.
    • Lu, Y.
  • Source: Journal of Triticeae Crops
  • Volume: 30
  • Issue: 2
  • Year: 2010
  • Summary: Field and pot experiments were carried out in China to investigate the effects of intercropping wheat with faba bean on manganese uptake by wheat plants grown under a paddy-upland rotation system. Samples of wheat plants and rhizosphere soil were taken at the tillering, stem elongation, heading, milking and ripening stages of wheat for various determinations. Exchangeable manganese (NH 4OAC-Mn) in the soil rhizosphere of intercropping wheat was significantly higher than that of continuous cropping. NH 4OAC-Mn content of row 1 (IW1) and row 3 (IW3) of intercropping wheat increased by 21.09% and 7.78% in the field experiment and by 37.63% in the pot experiment, respectively. However, manganese absorption of wheat intercropping showed no advantage at the stem elongation stage before heading. After heading, faba bean intercropped with wheat promoted the absorption of manganese in wheat. Manganese accumulation in the above-ground parts of wheat in IW1 and IW3 increased by 39.30% and 29.06% at the heading stage, by 51.50% and 65.30% at the milking stage and by 36.17% and 13.86% at the ripening stage in the field experiment, respectively. In the pot experiment, manganese accumulation in the above-ground intercropping wheat increased by 107.46, 36.07, 26.67, and 20.92%, respectively, at the tillering, stem elongation, milking and ripening stages. However, NH 4OAC-Mn content in rhizosphere soil of intercropping showed no accumulation. In conclusion, intercropping faba bean with wheat increased manganese available in the rhizosphere soil before heading and its uptake by the above-ground parts of the wheat plants, especially leaves and spike, at the milking stage.
  • Authors:
    • Jing, Q.
    • Dai, T.
    • Wollenweber, B.
    • Jiang, D.
    • Mu, H.
    • Cao, W.
  • Source: Journal of Agronomy and Crop Science
  • Volume: 196
  • Issue: 1
  • Year: 2010
  • Summary: Low radiation reduces wheat grain yield in tree-crop intercropping systems in the major wheat planting area of China. Here, two winter wheat ( Triticum aestivum L) cultivars, Yangmai 158 (shading tolerant) and Yangmai 11 (shading sensitive), were shaded from jointing to maturity to evaluate the impact of low radiation on crop growth, photosynthesis and yield. Grain yield losses and leaf area index (LAI) reduction were less than the reduction in solar radiation under both shading treatment in both cultivars. Compared with the control (S0), grain yield only reduced 6.4% and 9.9% under 22% shading treatment (S1), while 16.2% and 25.8% under 33% shading (S2) in Yangmai 158 and Yangmai 11 respectively. The reduction in LAI was 6.0% and 9.2% (S1), and 18.2% and 22.2% (S2) in Yangmai 158 and Yangmai 11 respectively. However, decline in canopy apparent photosynthetic rate (CAP) was 15.0-22.9% (S1) and 29.5-49.6% (S2), which was consistent with the reduction in radiation. The reduction in LAI was partially compensated by increases in the fraction of the top and bottom leaf area to the total leaf area, which facilitated to intercept more solar radiation by the canopy. The decrease in photosynthetic rate ( Pn) of flag leaf was partially compensated by the increase in Pn of the third leaf from the top. In addition, an inconsistency between the low Pn and the high Chl content in flag leaf was observed at 30 DAA. This could be explained that more excitation energy was dispersed via the non-photochemical approaches in the photosystem II (PSII) of flag leaf after long-term shading.
  • Authors:
    • Chai, Q.
    • Qi, W.
  • Source: Chinese Journal of Eco-Agriculture
  • Volume: 18
  • Issue: 1
  • Year: 2010
  • Summary: A field experiment was conducted in China to investigate the effect of different root partition patterns on wheat/maize competitiveness under intercropping system and how it affects yield. Two root partition patterns (plastic film and nylon mesh partition patterns) were used. Results showed that wheat/maize competitiveness in intercropping system steadily increased from sowing to flowering stage of wheat and then decreased the competitive advantage of wheat over maize under intercropping decreases by root partitioning. Intercropping system without root partition increased the competitive advantage of wheat by 20.5 and 4.9% respectively, compared to those with plastic film and nylon mesh partitions. The land equivalent ratios of intercropping systems without root partition, with plastic film partition and nylon mesh partition were 1.46, 1.20 and 1.39, respectively. Yield for the intercropping system was quadratically correlated with wheat competitiveness to maize. Improving wheat/maize competitiveness in intercropping systems increased yield. The stage of wheat flowering was critical for optimizing wheat competitiveness.
  • Authors:
    • Li, S.
    • Zheng, Y.
    • Tang, L.
    • Qiao, P.
  • Source: Plant Nutrition and Fertilizer Science
  • Volume: 16
  • Issue: 5
  • Year: 2010
  • Summary: Crop varieties are different in nutrient uptake, and intercropping may influence nutrient uptake and disease incidence of the crops. Pot experiments were carried out to investigate the characteristics of N, P and K uptake and powdery mildew incidence of 6 wheat cultivars, which differed in powdery mildew resistance and were intercropped with faba bean: 2 highly resistant cultivars YM47 and YM53, 2 medium resistant cultivars YM42 and YM51 and 2 sensitive cultivars YX11-12 and YX93-124. The biomass of YM47 and YM53 increased by 11.9% and 6.6% in intercropping, compared with that in mono-cropping. Nitrogen contents of the leaves of intercropped wheat cultivars YM47 and YM53 and YX11-12 significantly increased, by 1.20-1.25 times in comparison with those of mono-cropping. The phosphorus contents of wheat leaves increased at the milky and ripening stages, and potassium content of wheat leaves significantly increased by 9.1-22.3% at the jointing stage under the intercropping. The incidence of wheat powdery mildew of all wheat cultivars significantly decreased under the intercropping system, the relative disease controlling effects being 0.76-81.49%. The most desirable disease-controlling effects under the intercropping were observed in YM42, YM53 and YM93-142 at the milky stage.
  • Authors:
    • Wu, Z.
    • Yu, T.
    • Song, F.
    • Zhuoremu, T.
    • Shi, Y.
    • Hadier, Y.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 47
  • Issue: 5
  • Year: 2010
  • Summary: Objective: The microclimatic factors in different jujube-wheat intercropping densities (3 m * 4 m, 2 m * 6 m) and jujube-cotton intercropping densities (3 m * 4 m, 2 m * 6 m) were studied in the arid area of the Tarim basin, in order to improve theory of Jujube-crops intercropping, optimize intercropping model, and provide theoretic basis for crop selection. Method: Auto-meteorology Vantage Pro2 and portable meteorological instrument KS4000 were used to observe the microclimatic factors, such as light intensity, air temperature and humidity, wind speed and direction. The ground temperature was tested by WQG-15 thermomicro-climatemeter at same time. Result: The climatic factors changed to some extent with different jujube-crops intercropping systems. Within the same intercropping system, the micro-climate varied in different lines, especially for light intensity. Among the different intercropping system, the order of light intensity was 3*4 (m) jujube-wheat intercropping