• Authors:
    • Zhang, P.
    • Yan, J. P.
    • Xu, H. L.
    • Zhao, X. F.
  • Source: Acta Pedologica Sinica
  • Volume: 48
  • Issue: 6
  • Year: 2011
  • Summary: After comparative analysis of the distribution characteristics of soil water and salt in farmlands (3 cotton fields and 1 orchard) and their shelterbelts in drip irrigation prevailing Kalamiji Oasis in the lower reaches of Tarim River, Northwest China through comparative tests and field monitoring, effects of the current drip irrigation pattern on farmlands within forest networks and their shelterbelts and main factors affecting salt-water dynamics in the soil within the forest network were studied and analyzed with the following conclusions obtained. (1) In Kalamiji oasis, the groundwater table in the fields lowers at a rate of 0.5 m a -1 as a result of popularization of drip irrigation and varies seasonally; it is relatively shallow in non-irrigation season and relatively deep in irrigation season; and over 1 m deeper in the latter than in the former. (2) As the impact of drip irrigation on soil never goes deeper than 80 cm, the irrigation supplies little water, almost nil, to groundwater, while the roots of farmland shelterbelt have to go deep into the soil to absorb water, thus leading to significantly lower soil water content in the shelterbelt than in farmland ( p
  • Authors:
    • Ma, X. W.
    • Liu, H.
    • Xu, Y. M.
    • Chen, B. Y.
    • Niu, X. X.
    • Wang, B.
    • Yang, T.
    • Zhu, J. R.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 48
  • Issue: 4
  • Year: 2011
  • Summary: Objective: To reveal how water affects fertilizer is important to make decision to regulate and control water and fertilizer use. Method: The paper described temporal-spatial character of soil N extracted by alkaline affected by different irrigation water usage in Awati County, Xinjiang. Result: Irrigation resulted in change of soil N content in depth from 0 cm to 100 cm obviously, especially from 0 cm to 40 cm; generally the more water irrigated, the more nitrogen dissolved and moved down. Conclusion: One reason that water promoted fertilizer use efficiency was to enlarge distribution area of nitrogen in soil profile, then more cotton roots could adsorb nutrients.
  • Authors:
    • Gautam, M.
    • Ambati, R. R.
    • Reddy, A. R.
  • Source: Indian Journal of Agronomy
  • Volume: 56
  • Issue: 4
  • Year: 2011
  • Summary: Field trials were conducted to validate farm pond sizes for supplemental irrigations during 2004-2011 at the Central Institute for Cotton Research, Nagpur (′21degrees09′N, 79degrees09′E.). Ten farm ponds 200 to 15,120 m 3 size resulted in a runoff storage of about 60, 75 and 28, 36, 58% (2007, 2010 and 2008, 2009, 2011) in normal and drought years at the end of August month. During actual drought the water availability was 0 and 18% only of the capacity designed in 2011 and 2008 July seedling droughts. Special recharging techniques like opening borewells/percolation tanks etc in under ground storages and using it with sprinkler irrigation during seedling droughts is the only option. Two supplemental irrigations at flowering stage along with application of deficient micronutrients on shallow and medium soils to Bt hybrid cotton ( G. hirsutum L.) resulted in increased seed cotton yield by 50% and 44%, which was verified during 2008 and 2009 seasons in Yeotmal district. The minimum economical catchment was found to be 21 ha or 0.7 ha m pond size, with which 25% and 50% area could be irrigated by conventional and alternate furrow/sprinkler irrigation respectively, with a payback period (PBP) of 2 years in Bt hybrid cotton. Rotational soybean ( Glycine max (L.) Merrill) could be irrigated to the extent of 16 and 33% catchment area with improved water use efficiency (WUE) from 250 to 500 kg/ha-cm for 1.5 and 3.5 years of pay back period (PBP) under conventional and sprinkler irrigation, respectively, during drought conditions. The same sprinkler and drip irrigation systems could also be used to irrigate subsequent wheat [ Triticum aestivum (L.) emend. Fiori & Paol] crop with a gravitational well, covering 14 and 57% of catchment area with WUE of 180 kg/ha-cm with a PBP of 11 and 21 years.
  • Authors:
    • Tann, C. R.
    • Baker, G. H.
    • Fitt, G. P.
  • Source: Bulletin of Entomological Research
  • Volume: 101
  • Issue: 1
  • Year: 2011
  • Summary: Pheromone and light traps have often been used in ecological studies of two major noctuid pests of agriculture in Australia, Helicoverpa armigera and H. punctigera. However, results from these two methods have rarely been compared directly. We set pheromone and light traps adjacent to or amongst cotton and various other crops for 10-11 years in the Namoi Valley, in northern New South Wales, Australia. Catches in pheromone traps suggested a major peak in (male) numbers of H. punctigera in early spring, with relatively few moths caught later in the summer cropping season. In contrast, (male) H. armigera were most abundant in late summer. Similar trends were apparent for catches of both male and female H. armigera in light traps, but both sexes of H. punctigera were mostly caught in mid-summer. For both species, males were more commonly caught than females. These catch patterns differed from some previous reports. At least three generations of both species were apparent in the catches. There was some evidence that the abundance of later generations could be predicted from the size of earlier generations; but, unlike previous authors, we found no positive relationships between local winter rainfall and subsequent catches of moths, nor did we find persuasive evidence of correlations between autumn and winter rainfall in central Australia and the abundance of subsequent 1st generation H. punctigera moths. Female H. punctigera were consistently more mature (gravid) and more frequently mated than those of H. armigera. Overall, our results highlight the variability in trap catches of these two species and question the use of trap catches and weather as predictors of future abundance in cropping regions.
  • Authors:
    • Joshi, O. P.
    • Billore, S. D.
    • Bhatia, V. S.
    • Ramesh, A.
  • Source: Soybean Research
  • Volume: 9
  • Year: 2011
  • Summary: The work done so far on soybean-based intercropping systems in India involving crops like sorghum, maize, pigeonpea, pearl millet, cotton, sugarcane, minor millets, wheat, rice, oilseeds and plantation crops is reviewed. The compilation brings out the possibilities of rational utilization of natural resources by resorting to diversified cultivation rather than monoculture of crops. Soybean being a short duration leguminous crop with wide agro-climatic adaptability, offers a good opportunity to fit in cropping systems in different regions with added advantage of better economic returns, risk coverage and utilization of natural resources. The benefits of sustainability can be harnessed by adoption of scientifically evaluated and suggested intercropping systems.
  • Authors:
    • Blaise, D.
  • Source: Soil & Tillage Research
  • Volume: 114
  • Issue: 2
  • Year: 2011
  • Summary: Transgenic Bt cotton hybrids, in India, now constitute more than 90% of the cotton area. Conservation tillage systems such as reduced tillage (RT) improve soil health and crop productivity. Field experiments were conducted to study the response of Bt cotton hybrids to the tillage methods in a split plot design for three years (2005-2006 to 2007-2008) with tillage practices as main plots (conventional tillage {CT}, RT with two inter-row cultivations {RT(1)} and RT with no inter-row cultivation {RT(2)}). In the sub-plot, in situ green manure (GM) was included along with 100 (GM + N(100)), 80 (GM + N(80)) and 60 kg N ha(-1) (GM + N(60)) and were compared to N alone (N(100)). Growth, yield and fibre quality of Bt transgenic cotton hybrid (RCH-2 Bt) were monitored during the study. In all seasons, weed density and biomass were significantly lower in the RT treatments than in the CT treatments. Taller plants with more main stem nodes were produced on the RT plots (63.6-75.8 cm) than on the CT plots (58.1-70.2 cm). Thus, plants of RT treatment retained more bolls (60.8-62.0 m(-2)) than those of the CT treatment (52.4 m(-2)). Averaged over seasons, RT treatment had seed cotton yield (1717-1740 kg ha(-1)) significantly higher than the CT treatment (1489 kg ha(-1)). The treatments N(100), GM + N(100) and GM + N(80) (1687-1734 kg ha(-1)) did not differ and were significantly better than the GM + N(60) (1303 kg ha(-1)). Tillage x GM interaction was significant in two of three years and data combined over years. The RT plots with GM had significantly greater yield than the CT plots. Compared to the CT treatment, the RT plots had significantly greater proportion of water stable aggregates (48.6% vs. 54.4-56.0%) and mean weight diameter (0.47 mm vs. 0.49-0.51 mm). The GM plots had significantly higher WSA and MWD than those without. Further, soil moisture content was greater in the GM mulched plots up to 0.60 m depth compared to without GM treatment (CT + N(100)). Favourable soil physical properties may have contributed to improved seed cotton yield in the RT treatments with GM than in the CT treatment. Fibre quality was not affected by either the tillage systems or GM. This study indicates that Bt transgenic cotton can be grown under RT systems with an in situ legume GM. (C) 2011 Elsevier B.V. All rights reserved.
  • Authors:
    • Bagwan, N.
  • Source: International Journal of Plant Protection
  • Volume: 3
  • Issue: 2
  • Year: 2010
  • Summary: Crop root exudates of 20 crops like groundnut, soybean, pigeonpea, green gram, black gram, chickpea, pea, cowpea, mustard, cotton, castor, sunflower, safflower, sesamum, sorghum, pearl millet, maize, wheat, onion, and garlic were used in this study. Large variations of inhibitory effect of root exudates on S. rolfsii were observed. Low concentrations of root exudates (5% and 10%) had no effect on inhibition of mycelial growth and germination of sclerotia while, at high concentration (20%) inhibited the mycelial growth and germination of sclerotia. Mycelial growth, dry mycelium weight and sclerotial germination were recorded lowest in root exudates of sunflower, maize, pearl millet, sorghum, safflower, garlic, and onion. Mycelial growth, dry mycelium weight and sclerotial germination was recorded highest in root exudates of soybean, groundnut, green gram, black gram, pigeonpea, chickpea, pea and cowpea. It was observed that the root exudates of maize, sunflower and pearl millet showed a highest percentage of inhibition of mycelial growth and sclerotial germination. Another interesting of thing was observed that root exudates of groundnut, soybean and pea stimulate the mycelial growth and germination of sclerotia as compared to control. The results of this study suggested that the intercropping or crop rotation of safflower, maize, pearl millet, sorghum, sunflower, garlic, and onion with groundnut may be useful for the management of stem rot of groundnut and also for reduction of soil population of S. rolfsii in groundnut field. Similarly intercropping or crop rotation of soybean, green gram, black gram, chickpea, pea and cowpea with groundnut should be avoided. Based on these findings, it is hypothesized that root exudates of some crops contain antifungal compounds, while other stimulate the growth of fungal pathogens. Cultivation of safflower, maize, pearl millet and sorghum with groundnut could lead to a reduction in the occurrence of stem rot disease, especially when chemical control is not effective and economically costly. However, further investigation is necessary for isolation and identification of antifungal compounds in root exudates related to host-pathogen interaction.
  • Authors:
    • Elliott, N.
    • Giles, K.
    • Phoofolo, M.
  • Source: Environmental Entolomology
  • Volume: 39
  • Issue: 3
  • Year: 2010
  • Summary: Creating conditions that enhance the abundance of resident populations of natural enemies in agroecosystems is considered critical to the efficiency of biological control of insect pests. We conducted a study to determine the potential of relay-intercropping for enhancing the abundance of aphidophagous lady beetles in sorghum. A relay-intercropping system consisting of alfalfa, winter wheat, and cotton as intercrops and sorghum as a main crop was compared with sorghum monoculture plots at two study sites in OK from 2003 to 2006. Lady beetles and aphids were sampled throughout the season using sticky traps and field counts on individual sorghum plants. Results from sticky traps and field counts show that differences in abundance and species composition of lady beetles between intercropped and monoculture sorghum were not statistically different during each year of study. Also, the lady beetle-greenbug ratios in relay-intercropped and monoculture plots were not significantly different. Lack of significant effects of relay-intercropping in our study may have been attributable to the confounding effects of spatial and temporal scale and the low number of aphids and other alternative prey in the intercrops compared with high incidence of corn leaf aphids in sorghum early in the season.
  • 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
  • Authors:
    • Kumar, S. N.
    • Byjesh, K.
    • Aggarwal, P. K.
  • Source: Mitigation and Adaptation Strategies for Global Change
  • Volume: 15
  • Issue: 5
  • Year: 2010
  • Summary: Climate change associated global warming, rise in carbon dioxide concentration and uncertainties in precipitation has profound implications on Indian agriculture. Maize ( Zea mays L.), the third most important cereal crop in India, has a major role to play in country's food security. Thus, it is important to analyze the consequence of climate change on maize productivity in major maize producing regions in India and elucidate potential adaptive strategy to minimize the adverse effects. Calibrated and validated InfoCrop-MAIZE model was used for analyzing the impacts of increase in temperature, carbon dioxide (CO 2) and change in rainfall apart from HadCM3 A2a scenario for 2020, 2050 and 2080. The main insights from the analysis are threefold. First, maize yields in monsoon are projected to be adversely affected due to rise in atmospheric temperature; but increased rainfall can partly offset those loses. During winter, maize grain yield is projected to reduced with increase in temperature in two of the regions (Mid Indo-Gangetic Plains or MIGP, and Southern Plateau or SP), but in the Upper Indo-Gangetic Plain (UIGP), where relatively low temperatures prevail during winter, yield increased up to a 2.7°C rise in temperature. Variation in rainfall may not have a major impact on winter yields, as the crop is already well irrigated. Secondly, the spatio-temporal variations in projected changes in temperature and rainfall are likely to lead to differential impacts in the different regions. In particular, monsoon yield is reduced most in SP (up to 35%), winter yield is reduced most in MIGP (up to 55%), while UIGP yields are relatively unaffected. Third, developing new cultivars with growth pattern in changed climate scenarios similar to that of current varieties in present conditions could be an advantageous adaptation strategy for minimizing the vulnerability of maize production in India.