• Authors:
    • Tom, C. T.
    • Ngwuta, A. A.
    • Ibeawuchi, I. I.
    • Ogoke, I. J.
    • Onweremadu, E. U.
  • Source: Journal of Sustainable Agriculture
  • Volume: 33
  • Issue: 8
  • Year: 2009
  • Summary: Soil nutrient and physical status in small holder farms in southeastern Nigeria are subjected to debilitating effects of continuous cropping without adequate efforts towards replenishment and conservation to ensure sustainability of soil resources. Although inorganic fertilizers are quick acting for soil nutrient enhancement, to guarantee soil health they must be used within the context of integrated soil fertility management relative to soil type and other climatic conditions. On the other hand, apart from maintaining required nutrient levels, the use of appropriate crop combinations and arrangements in farmers' fields can improve soil health. Leguminous plants including tree, shrub and annual species have been determined to be useful components in such systems. These species can contribute immensely to soil carbon and other mineral contents in addition to improving soil physical properties. Apart from their high edible protein content, some leguminous seeds also have high phytate content, which should enhance the bioavailability of Zn, making them good nutrient sources in human and animal nutrition. However, indigenous leguminous tree, shrub, and grain legume species are currently underutilized in the common cropping systems on smallholder farms. While tree species are lost through logging, with very limited research toward their improvement, research on grain legumes has been limited in this zone resulting in the loss of indigenous grain species. Low available soil P is another constraint to legume cultivation in this region that has to be addressed through well coordinated agronomic research. Increased and sustainable food production on small holder farms in southeastern Nigeria is possible with improved practices within the prevailing cropping systems. This is achievable with intensive breeding, agronomic and utilization studies on legume species in the cropping systems.
  • Authors:
    • Suryawanshi, J. S.
    • Bhondave, T. S.
    • Ranshur, N. J.
    • Talathi, M. S.
    • Pinjari, S. S.
  • Source: International Journal of Agricultural Sciences
  • Volume: 5
  • Issue: 2
  • Year: 2009
  • Summary: Present investigation was carried out at Pulses Research Unit, DnPDKV, Akola (M.S.) during kharif and rabi season in wilt sick plot, in which fungi population was observed more in rhizosphere of sunflower, soybean, and groundnut as compared with sorghum, mung and udid. There was a gradual increase in the propagules of Fusarium oxysporum f.sp. ciceri from sowing to harvesting of chickpea. In correlation study the inoculum range of 10.11 to 14.00 per cent was recorded and there was positive but non-significant correlation between the inoculum available and the wilt incidence in chickpea.
  • Authors:
    • Feltran, J. C.
    • De Castro, C. M.
    • De Almeida, D. L.
    • Valle, Teresa L.
    • Duarte Ribeiro, R. De L.
    • Pries Devide, A. C.
  • Source: Bragantia
  • Volume: 68
  • Issue: 1
  • Year: 2009
  • Summary: Organic systems were evaluated for cassava root production directed to human comsumption in natura, at Seropedica-RJ. Treatments consisted of: cassava ('IAC 576-70') in single cropping and its intercropping with corn ('Eldorado'), cowpea ('Maua') or corn plus cowpea. The organic management was standardized and the experimental area was submitted to artificial irrigation during the period of stay of maize in the system. "Green" (immature) corn ears were harvested at the "point" required for fresh marketing and the shoot placed on the ground. The cowpea was included to function as green manure being Cut at flowering with residues left on the soil Surface. Corn and cowpea were sown between cassava rows, in an alternate design, following the first weeding of the main crop (cassava). The cultivar IAC 576-70 showed suitability with respect to organic management, yielding approximatelu 31 Mg ha(-1) of marketable roots. No significant differences were detected between cassava single cropping and any of the intercropping tested systems. Thus, corn crop has considerable potential for additional income to the growers. Yield of 'Eldorado' corn averaged 18.125 ears ha(-1) correspponding to 5,1 Mg ha-1. Residues coming from cowpea cutting brought about an input close to 12 Mg ha(-1), which meant an expressive contribution in nutrient elements, especially nitrogen (about 44 kg N ha(-1)). The legume crop, in addition, completely covered cassava inter-rows demonstrating its potential for controlling erosion and weeds. The triple intercropping becomes advantageous considering that corn harvesting would justify irrigation and that inclusion of cowpea meant benefitial effects to the system and did not interfere on cassava yield.
  • Authors:
    • Deen, W.
    • Earl, H.
    • Queen, A.
  • Source: Agronomy Journal
  • Volume: 101
  • Issue: 6
  • Year: 2009
  • Summary: Red clover (Trifolium pratense L.) use as an underseeded cover crop in winter cereals has declined due to inability of growers to consistently establish uniform stands. The objective of this study was to assess the effect of light and soil moisture competition on underseeded red clover establishment and end of season dry matter production. Field trials were conducted at multiple locations in 2005 and 2006 in Ontario, Canada. Wheat (Triticum aestivum L.) N rate (67 and 135 kg N ha(-1)) and row thinning treatments (19-cm rows, every third 19-cm row removed at the 4-5 leaf stage) were used to alter light penetration and soil moisture competition. The high N rate and row thinning treatments consistently reduced light penetration, beginning as early as wheat stem elongation initiation, but had no effect on soil gravimetric moisture content. Soil moisture was primarily affected by location and year. Red clover dry weight in 2005, a relatively dry year, ranged from 688 to 1184 kg ha(-1), and in 2006, a relatively wet year, ranged from 2336 to 2805 kg ha(-1). Average final red clover stand count was 23 plants m(-2) in 2005 and 55 plants m(-2) in 2006. In 2005, plant mortality occurred before wheat anthesis. In both years, and at most locations, red clover final dry weight was positively correlated with light penetration, again beginning as early as initiation of wheat stem elongation. Final red clover dry weight in both years and red clover stand count in 2005 were correlated with soil gravimetric water content during wheat anthesis, but this was primarily due to location and year effects. Although both light penetration through the wheat canopy and soil moisture influence biomass production of underseeded red Clover, soil moisture has the greater influence and is altered very little by wheat management.
  • Authors:
    • Jadon, C.
    • Meena, D. S.
    • Kumar, R.
  • Source: Haryana Journal of Agronomy ALSO THE JOURNAL OF RURAL AND AGRICULURAL RESEARCH, pp. 17-18, June, 2010
  • Volume: 25
  • Issue: 1/2
  • Year: 2009
  • Summary: The field experiment was undertaken during 2004-05 to 2007-08 on ARS, Kota to evaluate the performance of soybean-wheat, soybean-chickpea, soybean-coriander and soybean-onion cropping sequences in heavy textured, non-calcareous soils. The results revealed that soybean-onion sequence was more productive and remunerative compared to other sequences in irrigated areas of humid southeastern plain of Rajasthan.
  • Authors:
    • Khating, L. E.
    • Shirale, S. T.
  • Source: Annals of Plant Physiology
  • Volume: 23
  • Issue: 1
  • Year: 2009
  • Summary: A field experiment was conducted on clay soil (Typic Haplusterts) of MAU, Parbhani during 2002-03 to study the effect of application of organic, inorganic and organic combined with inorganic nutrient sources on yield of various cropping systems, NPK uptake and balance in soil. Recommended dose of fertilizers and combined application of glyricidia @1.5 t ha -1+25% RDF increased grain yield and N, P, K uptake. The highest total grain yield (2335 kg ha -1) was recorded by RDF fallowed by glyricidia @1.5 t ha -1+25% RDF (2213 kg ha -1) and it was at par with each other. The cropping systems sorghum+pigeonpea recorded highest yield (2438 kg ha -1). The maximum N, P and K uptake (142.16, 23.92 and 63.71 kg ha -1 respectively) was recorded with the soybean+pigeonpea cropping system. There, was more buildup of available N, P and K in soil with soybean+pigeonpea cropping system with FYM followed by glyricidia.
  • Authors:
    • Zudilin, S. N.
  • Source: Kormoproizvodstvo
  • Issue: 2
  • Year: 2009
  • Summary: Productivity of fodder crop rotation was studied in the Samara Region, Russia in 1993-2004. The fodder crop rotation consisted of 7 following combinations: (1) rape and radish; (2) winter wheat; (3) pea; (4) maize; (5) vetch and oat; (6) pea and barley and (7) goat's-rue. The most productive crop was goat's-rue which showed green mass yield of 20.27 t/ha. Rape, maize, vetch and oat mix had green mass yield of 19.78, 20.11 and 16.42 t/ha, respectively. Winter wheat and pea produced 2.4 and 1.18 t/ha of grain, respectively. Application of mineral fertilizers increased yield by 25-40%. Detailed data are presented in 2 tables.
  • Authors:
    • Miyao, G.
    • Jackson, J.
    • Mitchell, J. P.
    • Horwath, W. R.
    • Doane, T. A.
    • Brittan, K.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 85
  • Issue: 3
  • Year: 2009
  • Summary: In spite of potential benefits and positive assessments of reducing primary tillage operations, only a small part of irrigated row crops is currently managed using reduced tillage, for reasons that include concerns about its agronomic suitability for certain crop rotations. Three years of a tomato/corn rotation under standard and no-tillage management were used to understand the fate of a fertilizer and cover crop nitrogen (N) application. Uptake of both inputs was reduced under no-tillage during the year of application, in this case a tomato crop. As a result, more input N was retained in the soil in this system. The initial challenge of reduced tomato yields diminished as no-tillage management remained in place and the soil N reservoir developed. Corn production was not affected by tillage treatment. Inclusion of a legume cover crop increased the amount of fertilizer N retained in the soil over time, more so under no-tillage than under standard tillage, emphasizing the benefit of cover crops in reducing the amount of fertilizer required to maintain productivity. While acceptance of reduced tillage ultimately depends on economic performance, the results of this study support its agronomic viability for irrigated row crops.
  • Authors:
    • Drinkwater, L. E.
    • Gardner, J. B.
  • Source: Ecological Applications
  • Volume: 19
  • Issue: 8
  • Year: 2009
  • Summary: Intensively managed grain farms are saturated with large inputs of nitrogen (N) fertilizer, leading to N losses and environmental degradation. Despite decades of research directed toward reducing N losses from agroecosystems, progress has been minimal, and the currently promoted best management practices are not necessarily the most effective. We investigated the fate of N additions to temperate grain agroecosystems using a meta-analysis of 217 field-scale studies that followed the stable isotope N-15 in crops and soil. We compared management practices that alter inorganic fertilizer additions, such as application timing or reduced N fertilizer rates, to practices that re-couple the biogeochemical cycles of carbon (C) and N, such as organic N sources and diversified crop rotations, and analyzed the following response variables: N-15 recovery in crops, total recovery of N-15 in crops and soil, and crop yield. More of the literature (94%) emphasized crop recovery of N-15 than total N-15 recovery in crops and soil (58%), though total recovery is a more ecologically appropriate indicator for assessing N losses. Findings show wide differences in the ability of management practices to improve N use efficiency. Practices that aimed to increase crop uptake of commercial fertilizer had a lower impact on total N-15 recovery (3-21% increase) than practices that re-coupled C and N cycling (30-42% increase). A majority of studies (66%) were only one growing season long, which poses a particular problem when organic N sources are used because crops recover N from these sources over several years. These short-term studies neglect significant ecological processes that occur over longer time scales. Field-scale mass balance calculations using the N-15 data set show that, on average, 43 kg N.ha(-1).yr(-1) was unaccounted for at the end of one growing season out of 114 kg N.ha(-1).yr(-1), representing similar to 38% of the total N-15 applied. This comprehensive assessment of stable-isotope research on agroecosystem N management can inform the development of policies to mitigate nonpoint source pollution. Nitrogen management practices that most effectively increase N retention are not currently being promoted and are rare on the landscape in the United States.
  • Authors:
    • Beber Vieira, F. C.
    • Zanatta, J. A.
    • Piccolo, M. d. C.
    • Costa, F. d. S.
    • Bayer, C.
    • Gomes, J.
    • Six, J.
  • Source: Soil & Tillage Research
  • Volume: 106
  • Issue: 1
  • Year: 2009
  • Summary: It has been shown that cover crops can enhance soil nitrous oxide (N(2)O) emissions, but the magnitude of increase depends on the quantity and quality of the crop residues. Therefore, this study aimed to evaluate the effect of long-term (19 and 21 years) no-till maize crop rotations including grass [black oat (Avena strigosa Schreb)] and legume cover crops [vetch (Vigna sativa L), cowpea (Vigna unguiculata L. Walp), pigeon pea (Cajanus cajan L. Millsp.) and lablab (Dolichos lablab)] on annual soil N(2)O emissions in a subtropical Acrisol in Southern Brazil. Greater soil N(2)O emissions were observed in the first 45 days after the cover crop residue management in all crop rotations, varying from -20.2 +/- 1.9 to 163.9 +/- 24.3 mu g N m(-2) h(-1). Legume-based crop rotations had the largest cumulative emissions in this period, which were directly related to the quantity of N (r(2) = 0.60, p = 0.13)and inversely related to the lignin:N ratio(r(2) = 0.89,p = 0.01) of the cover crop residues. After this period, the mean fluxes were smaller and were closely related to the total soil N stocks (r(2) = 0.96, p = 0.002). The annual soil N(2)O emission represented 0.39-0.75% of the total N added by the legume cover crops. Management-control led soil variables such as mineral N (NO(3)(-) and NH(4)(+)) and dissolved organic C influenced more the N(2)O fluxes than environmental-related variables as water-filled pore space and air and soil temperature. Consequently, the synchronization between N mineralization and N uptake by plants seems to be the main challenge to reduce N(2)O emissions while maintaining the environmental and agronomic services provided by legume cover crops in agricultural systems. (C) 2009 Elsevier B.V. All rights reserved.