19952015
  • Authors:
    • Srinivasarao, C.
    • Vittal, K.
  • Source: Indian Journal of Fertilisers
  • Volume: 3
  • Issue: 5
  • Year: 2007
  • Summary: Soil samples from 21 locations of the All India Coordinated Research Project for Dryland Agriculture (AICRPDA) were characterized for organic carbon and availability of nutrients such as nitrogen, phosphorus, potassium, sulfur, Ca, Mg, Zn, Fe, Mn, Cu and B. These twenty one locations cover agro-ecological regions from 2.3 to 12.3, semiarid, and sub-humid climate, soils examined were Vertisols, Vertic sub-groups, Affisols, Inceptisols and Aridisols from different Indian states including Uttar Pradesh, Punjab, Jammu and Kashmir, Orissa, Jharkhand, Andhra Pradesh, Karnataka, Gujarat, Madhya Pradesh, Maharshtra, Tamil Nadu, Rajasthan, and Haryana. Representative soil profile samples from following production systems were collected: upland rice, groundnut, soyabeans, cotton,Rabi sorghum, pearlmillet, fingermillet and maize-based system. Rainfall ranged from 412 to 1378 mm among locations. Various physico-chemical properties of the 21 profiles indicated that most of the locations were low in organic carbon showing less than 0.5% organic C. Clay content varied widely among soil types. Low organic matter in these soils was one of the important factors contributing to low soil fertility. Except few locations, most of the soils were low in available N. Available P varied from low to very high. Available K and sulfur varied from low to high. Available Zn was below critical limit in Rajkot, Anatapur, Rewa, Akola, Bellary, Bijapur and Solapur, Agra, S.K. Nagar, Arjia, Hoshiarpur and Rakh Dhiansar. Iron was deficient in Rajkot, Bellary and Bijapur. Surface layers of several profiles were deficient in available Ca (<1.5 me 100/g) such as Phulbani, Anantapur, S.K. Nagar and Bangalore. Surface layers of soils at Phulbani, Ranchi, Anantapur, Agra, Hisar, S.K. Nagar, Bangalore, Arjia, Hoshiarpur and Rakh Dhiansar were Mg deficient (<1.0 me 100/g). Out of the 21 locations, 11 were boron deficient. Except Indore, all other soils were multinutrient deficient. Results suggest that dryland soils are multinutrient deficient, thus proper nutrient management strategies and soil water conservation practices in dryland agriculture are needed.
  • Authors:
    • Grace, P.
    • Rochester, I.
    • Crothers, B.
    • Chen, D.
    • Weier, K.
    • Rowlings, D.
    • Kiese, R.
    • Butterbach-Bahl, K.
    • Li, Y.
  • Source: Non-CO2 Greenhouse Gas Fluxes in Australian-New Zealand Landscapes
  • Year: 2007
  • Authors:
    • Lachnicht-Weyers, S. L.
    • Tillman, P. G.
    • Whitehead, P. G.
    • Singh, B. P.
    • Schomberg, H. H.
    • Sainju, U. M.
  • Source: Soil & Tillage Research
  • Volume: 96
  • Year: 2007
  • Summary: Cover crops may influence soil carbon (C) sequestration and microbial biomass and activities by providing additional residue C to soil. We examined the influence of legume [crimson clover (Trifolium incarnatum L.)], nonlegume [rye (Secale cereale L.)], blend [a mixture of legumes containing balansa clover (Trifolium michelianum Savi), hairy vetch (Vicia villosa Roth), and crimson clover], and rye + blendfmixture cover crops on soil C fractions at the 0-150 mm depth from 2001 to 2003. Active fractions of soil C included potential C mineralization (PCM) and microbial biomass C (MBC) and slow fraction as soil organic C (SOC). Experiments were conducted in Dothan sandy loam (fine-loamy, kaolinitic, thermic, Plinthic Kandiudults) under dryland cotton (Gossypium hirsutum L.) in central Georgia and in Tifton loamy sand (fine-loamy, siliceous, thermic, Plinthic Kandiudults) under irrigated cotton in southern Georgia, USA. Both dryland and irrigated cotton were planted in strip tillage system where planting rows were tilled, thereby leaving the areas between rows untilled. Total aboveground cover crop and cotton C in dryland and irrigated conditions were 0.72-2.90 Mg C ha-1 greater in rye + blend than in other cover crops in 2001 but was 1.15-2.24 Mg C ha-1 greater in rye than in blend and rye + blend in 2002. In dryland cotton, PCM at 50-150 mm was greater in June 2001 and 2002 than in January 2003 but MBC at 0-150 mm was greater in January 2003 than in June 2001. In irrigated cotton, SOC at 0-150 mm was greater with rye + blend than with crimson clover and at 0-50 mm was greater in March than in December 2002. The PCM at 0-50 and 0-150 mm was greater with blend and crimson clover than with rye in April 2001 and was greater with crimson clover than with rye and rye + blend in March 2002. The MBC at 0-50 mm was greater with rye than with blend and crimson clover in April 2001 and was greater with rye, blend, and rye + blend than with crimson clover in March 2002. As a result, PCM decreased by 21-24 g CO2-C ha-1 d-1 but MBC increased by 90-224 g CO2-C ha-1 d-1 from June 2001 to January 2003 in dryland cotton. In irrigated cotton, SOC decreased by 0.1-1.1 kg C ha-1 d-1, and PCM decreased by 10 g CO2-C ha-1 d-1 with rye to 79 g CO2-C ha-1 d-1 with blend, but MBC increased by 13 g CO2-C ha-1 d-1 with blend to 120 g CO2-C ha-1 d-1 with crimson clover from April 2001 to December 2002. Soil active C fractions varied between seasons due to differences in temperature, water content, and substrate availability in dryland cotton, regardless of cover crops. In irrigated cotton, increase in crop C input with legume + nonlegume treatment increased soil C storage and microbial biomass but lower C/N ratio of legume cover crops increased C mineralization and microbial activities in the spring.
  • Authors:
    • Mitchell, J. P.
    • Horwath, W. R.
    • Veenstra, J. J.
  • Source: Soil Science Society of America Journal
  • Volume: 71
  • Issue: 2
  • Year: 2007
  • Summary: Conservation tillage (CT) and cover cropping (CC) are agricultural practices that may provide solutions to address water and air quality issues arising from intensive agricultural practices. This study investigated how CT and CC affect soil organic matter dynamics in a cotton(Gossypium hirsutum L.)-tomato (Lycopersicon esculentum Mill.) rotation in California's San Joaquin Valley. There were four treatments: conservation tillage, no cover crop (CTNO); conservation tillage with cover crop (CTCC); standard tillage, no cover crop (STNO); and standard tillage with cover crop (STCC). After 5 yr, the top 30 cm of soil in CTCC had an increase of 4500 kg C ha(-1), compared with an increase of 3800 kg C hat in STCC from initial soil C content in 1999. To enhance our understanding of C dynamics in CT systems, we pulse-labeled cotton with (CO2)-C-13 in the field and followed the decomposition of both the roots and the shoots through three physical fractions: light fraction (LF), which tends to turnover quickly, and two relatively stable C pools-intraaggregate LF (iLF) and mineral-associated carbon (mC). Soil under CT treatments retained more of the cotton-residue-derived C in LF and iLF than ST 3 mo after placement in the field. These differences disappeared after 1 yr, however, with no discernable differences between CT and ST regardless of CC. In California's Mediterranean climate, CT alone does not accumulate or stabilize more C than ST in tomato-cotton rotations, and the addition of cover crop biomass is more important than tillage reduction for total soil C accumulation.
  • Authors:
    • An, M.
    • Cheema, Z. A.
    • Iqbal, J.
  • Source: Plant and Soil
  • Volume: 300
  • Issue: 1/2
  • Year: 2007
  • Summary: A 2-year field investigation was carried out during 2003-2004 to determine the effectiveness of intercropping single and double rows of sorghum, soybean and sesame in a cotton crop on the suppression of purple nutsedge ( Cyperus rotundus L.). Results revealed that all three intercrops were effective in inhibiting purple nutsedge density (70-96%) and dry matter production (71-97%) during both years of experimentation. Control in the second year was more effective than in the first year. The seed cotton yield was also depressed by the intercrops but its suppression (8-23%) was far less severe than that of purple nutsedge and its loss was compensated by greater total economic returns. Intercropping of sorghum and sesame produced greater than 20% net benefits (up to 60%) in comparison with the control (cotton alone). Soybean intercropping produced comparable net benefits (95-103%). Sesame two rows intercrop treatment appeared the most profitable with net benefit of 51-59% with good purple nutsedge control (73-92% density suppression, 77-95% dry weight suppression) during both years of experimentation.
  • Authors:
    • Burmester, C.
    • Reeves, D. W.
    • Motta, A. C. V.
    • Feng, Y.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 38
  • Issue: 19-20
  • Year: 2007
  • Summary: The impact of conservation tillage, crop rotation, and cover cropping on soil-quality indicators was evaluated in a long-term experiment for cotton. Compared to conventional-tillage cotton, other treatments had 3.4 to 7.7 Mg ha(-1) more carbon (C) over all soil depths. The particulate organic matter C (POMc) accounts for 29 to 48 and 16 to 22% of soil organic C (SOC) for the 0- to 3- and 3- to 6-cm depths, respectively. Tillage had a strongth influence on POMc within the 0- to 3-cm depth, but cropping intensity and cover crop did not affect POW A large stratification for microbial biomass was observed varing from 221 to 434 and 63 to 110 mg kg(-1) within depth of 0-3 and 12-24 cm respectively. The microbial biomass is a more sensitive indicator (compared to SOC) of management impacts, showing clear effect of tillage, rotation, and cropping intensity. The no-tillage cotton double-cropped wheat/soybean system that combined high cropping intensity and crop rotation provided the best soil quality.
  • Authors:
    • McGawley, E. C.
    • Pontif, M. J.
  • Source: Nematropica
  • Volume: 37
  • Issue: 2
  • Year: 2007
  • Summary: Reniform nematodes that parasitize cotton and soybean can also reproduce on a wide spectrum of weed species, thereby maintaining nematode populations during the off-season. Microplot studies were conducted to evaluate the effects of three endemic weed species, morningglory ( Ipomoea lacunosa), hemp sesbania ( Sesbania exaltata), and johnsongrass ( Sorghum halepense), on reproduction of the reniform nematode, Rotylenchulus reniformison cotton (LA. 887) and soybean (Pioneer 96B21). Over two years of microplot trials, the co-culture of cotton with any of the three weed species suppressed numbers of reniform nematode juveniles in soil significantly. When grown singly, reproductive values of R. reniformis after 60 days on cotton averaged 69.0, while those for morningglory, hemp sesbania, and johnsongrass averaged 42.0, 23.5, and 18.0, respectively. Reproductive values on cotton co-cultured with morningglory averaged 38.5. Those for the cotton-hemp sesbania and cotton-johnsongrass combinations averaged 23.5 and 26.0, respectively. Nematode reproduction on soybean alone, and co-cultured with each of the three weeds, reduced reproduction of reniform nematode only in the presence of johnsongrass in two trials. Data from two subsequent 45-day duration greenhouse experiments conducted with cotton and leachates from each of the three weed species support the hypothesis that suppression of reniform nematode reproduction likely resulted from the secretion of allelopathic compounds by weed roots.
  • Authors:
    • Tiwary ,P.
    • Manual, D. K.
    • Prasad, J.
    • Hajare, T. N.
    • Challa, O.
  • Source: Agropedology
  • Volume: 17
  • Issue: 1
  • Year: 2007
  • Summary: An experiment was conducted to compare the production potential and economic feasibility of various crop combinations, i.e. cotton (cv. Anjali 561) intercropped with cowpea, urd bean and dhaincha, and soyabean (cv. JS 335) intercropped with maize, sorghum and pigeon pea, under rainfed farming conditions in Nagpur, Maharashtra, India, during 2002-04. The soils of the area are 22-24 cm deep (underlain by murrum/saprolite up to 40-45 cm), well-drained (Lithic Ustorthents) and occur on 1-3 and 3-5% slope. Cotton intercropping comprised row to row at 90 cm and plant to plant at 45 cm, while soyabean intercropping comprised 2 rows of main and 2 rows of intercrop at 45 cm. Irrespective of the slope, the highest yield of cotton was recorded under cotton + cowpea cropping system; however, the highest net return was observed under cotton + cowpea cropping system. For soyabeans, the highest yield was recorded under sole soyabean crop in both soil slopes. Among the intercropping systems, soyabean + pigeon pea had the highest yield followed by sorghum under both slopes during 2002-03. In 2003-04, soyabean + sorghum gave the highest soyabean equivalent yield in both soils followed by soyabean + pigeon pea. Comparative data on gross return, net return, average net profit and land equivalent ratio for both cotton and soyabean cropping systems are also presented.
  • Authors:
    • listed as anonymous
  • Source: Egyptian Journal of Plant Breeding
  • Volume: 11
  • Issue: 1
  • Year: 2007
  • Summary: These proceedings contain 30 papers on the various aspects of plant breeding including heterosis, combining ability and inheritance studies, characterization of cultivars, performance evaluation and genetic improvement of field crops (including wheat, cotton, soyabean, maize, rice, barley, rape, sorghum and faba bean) and horticultural crops (e.g. mango, tomato, pepper and grape).
  • Authors:
    • Awasthi, V. B.
  • Source: Agricultural insect pests and their control
  • Year: 2007
  • Summary: This book, which contains 24 chapters, covers the morphology (integument, head, thorax and abdomen), physiology (digestive system, circulatory system, excretory system, respiratory system, nervous system, photoreceptors, endocrine system, and reproductive system), development and metamorphosis, and control (through physical, mechanical, biological, chemical and integrated management strategies, and through quarantine and the use of pheromones) of agricultural insect pests. An overview of the life history and control of pests of cotton and fibre crops, sugarcane, oilseed crops, pulse crops, sorghum, cereals, fruits and fruit trees, vegetables, plantation crops, soyabean, ornamental plants, and stored grains is provided. This book is intended for students of agricultural entomology in India, but will also be useful for those who are preparing for examinations for admission in government agencies.