• 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:
    • Anderson, R. L.
    • Beck, D. L.
  • Source: Weed Technology
  • Volume: 21
  • Issue: 1
  • Year: 2007
  • Summary: Producers in the Great Plains are exploring alternative crop rotations with the goal of reducing the use of fallow. In 1990, a study was established with no-till practices to compare 8 rotations comprising various combinations of winter wheat (W), spring wheat (SW), maize (C), chickpea (CP), dry pea (Pea), soyabean (SB), or fallow (F). After 12 years, we characterized weed communities by recording seedling emergence in each rotation. Downy brome ( Bromus tectorum), cheat ( Bromus secalinus), redroot pigweed ( Amaranthus retroflexus), and green foxtail ( Setaria viridis) were the most common weeds observed. Weed community density was highest for W-CP, being 13-fold greater than with Pea-W-C-SB. Downy brome and cheat were rarely observed in rotations where winter wheat was grown only once every 3 or 4 years; in contrast, density of the brome species was 75-fold greater in W-CP. Warm-season weeds were also affected by rotation design; density of redroot pigweed and green foxtail was 6-fold greater in W-C-CP compared with Pea-W-C-SB or W-F. One rotation design that was especially favourable for low weed density was arranging crops in a cycle of 4, with 2 cool-season crops followed by 2 warm-season crops.
  • 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.
  • Authors:
    • Vigil, M. F.
    • Nielsen, D. C.
    • Mikha, M.
    • Benjamin, J. G.
    • Calderon, F.
    • Henry, W. B.
  • Source: Soil Science Society of America Journal
  • Volume: 71
  • Issue: 4
  • Year: 2007
  • Summary: No-till cropping systems in the semiarid West have the potential to improve soil physical properties by increasing cropping intensity and crop diversity. An investigation at Akron, Colorado, USA, compared soil conditions in winter wheat ( Triticum aestivum)-summer fallow (WF) plots with soil conditions in wheat-maize ( Zea mays)-fallow (WCF), wheat-maize-sunflower ( Helianthus annuus)-fallow (WCSF), wheat-maize-millet ( Panicum miliaceum) (WCM), and a perennial grass/legume mix. The study began in 1990. Bulk density, pore size distribution, and saturated hydraulic conductivity were measured 7, 11, and 15 years after inception. Bulk density in the grass plots decreased from 1.39 to 1.25 Mg m -3 in 15 years. Bulk density in the annually cropped plots decreased from 1.38 to 1.30 Mg m -3 during the same time period. The pore size distribution became more uniform among the cropped treatments 15 years after the start of the experiment. Saturated hydraulic conductivity increased in the grass plots from 27 to 98 mm h -1 in 15 years. Saturated hydraulic conductivity in the annually cropped plots increased from approximately 14 to approximately 35 mm h -1 during the same period. The results show that improving soil physical properties by cropping system alone may take many years. Perennial vegetation may be more effective than annually cropped systems at improving soil physical conditions because of less surface compaction from planting operations and the apparent ability of perennial root systems to create a more stable, continuous pore network.
  • Authors:
    • Pala, M.
  • Source: Options Mediterraneennes. Serie A, Seminaires Mediterraneens
  • Issue: 69
  • Year: 2006
  • Summary: The past several decades have witnessed a change from traditional to more intensive agriculture in dryland farming systems of West Asia and North Africa and also in the transitional period of Central Asia and Caucasus (CAC). These two areas can be combined and called the Central and West Asia and North Africa (CWANA) region, which covers diverse agroecological conditions from mild lowlands (Syria) to cold continental (CAC) and cold highlands (Turkey). This region is a major area of the world where drought invariably limits crop production in approximately 1.7 million ha arable land. Agriculture is primarily based on rainfed cropping during the relatively cooler late autumn to early spring as rainfall ranged generally between 200 to 600 mm per year. Dryland crops are mainly wheat, food legumes such as lentil, chickpea, faba beans, and forage legumes such as vetch, medics and lathyrus. Increasing human and livestock population has led desertification and soil degradation in the region. This has led also ICARDA to an assessment of tillage systems for efficiency, enhanced productivity and sustainability of the various farming system changes through a series of long-term trials in the mid 1980s at ICARDA headquarter as well as in the National Agricultural Research Services in close collaboration. Results at ICARDA and the region support a preference for the conservation tillage system (minimum tillage) over deep tillage systems on the grounds of both energy-use efficiency and increased net revenue as direct benefits to livelihood of the rural population. However, whenever available and tested and adopted by farmers with their participatory evaluation as in Central Asia, no-till direct drilling would increase soil organic matter from approximately 0.9% to 1.3% at 0-10 cm top soil and sustain the systems productivity in the long-run on the basis of the initial research results throughout the CWANA region.
  • Authors:
    • Waddell, J.
    • Lenssen, A.
    • Sainju, U. M.
    • Caesar-Tonthat, T.
  • Source: Soil Science Society of America Journal
  • Volume: 70
  • Issue: 2
  • Year: 2006
  • Summary: Sustainable management practices are needed to enhance soil productivity in degraded dryland soils in the northern Great Plains. We examined the effects of two tillage practices [conventional till (CT) and no-till (NT)], five crop rotations [continuous spring wheat (Triticum aestivum L.) (CW), spring wheat-fallow (W-F), spring wheat-lentil (Lens culinaris Medic.) (W-L), spring wheat-spring wheat-fallow (W-W-F), and spring wheat-pea (Pisum sativum L.)fallow (W-P-F)], and a Conservation Reserve Program (CRP) on plant biomass returned to the soil, residue C and N, and soil organic C (SOC), soil total N (STN), and particulate organic C and N (POC and PON) at the 0- to 20-cm depth. A field experiment was conducted in a mixture of Scobey clay loam (fine, smectitic, frigid Aridic Argiustolls) and Kevin clay loam (fine-loamy, mixed, superactive, frigid Aridic Argiustolls) from 1998 to 2003 near Havre, MT. Mean annualized plant biomass returned to the soil from 1998 to 2003 was greater in W-F (2.02 Mg ha(-1)) than in W-L and W-W-F, regardless of tillage. In 2004, residue cover was greater in CW (60%) than in other rotations, except in W-W-E Residue amount and C and N contents were greater in NT with CW (2.47 Mg ha(-1) and 963 and 22 kg ha(-1), respectively) than in NT with W-L and CT with other crop rotations. The POC at 0 to 5 cm was greater in W-W-F and W-P-F (2.1-2.2 Mg ha(-1)) than in W-L. Similarly, STN at 5 to 20 cm was greater in CT with W-L (2.21 Mg ha(-1)) than in other treatments, except in NT with W-W-E Reduced tillage and increased cropping intensity, such as NT with CW and W-L, conserved C and N in dryland soils and crop residue better than the traditional practice, CT with W-F, and their contents were similar to or better than in CRP planting.
  • Authors:
    • Lenssen, A.
    • Caesar-Thonthat, T.
    • Waddell, J.
    • Sainju, U. M.
  • Source: Journal of Environmental Quality
  • Volume: 35
  • Issue: 4
  • Year: 2006
  • Summary: Long-term use of conventional tillage and wheat (Triticum aestivum L.)-fallow systems in the northern Great Plains have resulted in low soil organic carbon (SOC) levels. We examined the effects of two tillage practices [conventional till (CT) and no-till (NT)], five crop rotations [continuous spring wheat (CW), spring wheat-fallow (W-F), spring wheat-lentil (Lens culinaris Medic.) (W-L), spring wheat-spring wheat-fallow (W-W-F), and spring wheat-pea (Pisum sativum L.)-fallow (W-P-F)], and Conservation Reserve Program (CRP) planting on plant C input, SOC, and particulate organic carbon (POC). A field experiment was conducted in a mixture of Scobey clay loam (fine-loamy, mixed, Aridic Argiborolls) and Kevin clay loam (fine, montmorillonitic, Aridic Argiborolls) from 1998 to 2003 in Havre, MT. Total plant biomass returned to the soil from 1998 to 2003 was greater in CW (15.5 Mg ha(-1)) than in other rotations. Residue cover, amount, and C content in 2004 were 33 to 86% greater in NT than in CT and greater in CRP than in crop rotations. Residue amount (2.47 Mg ha(-1)) and C content (0.96 Mg ha(-1)) were greater in NT with CW than in other treatments, except in CT with CRP and W-F and in NT with CRP and W-W-E The SOC at the 0- to 5-cm depth was 23% greater in NT (6.4 Mg ha(-1)) than in CT. The POC was not influenced by tillage and crop rotation, but POC to SOC ratio at the 0- to 20-cm depth was greater in NT with W-L (369 g kg(-1) SOC) than in CT with CW, W-F, and W-L. From 1998 to 2003, SOC at the 0- to 20-cm depth decreased by 4% in CT but increased by 3% in NT. Carbon can be sequestered in dryland soils and plant residue in areas previously under CRP using reduced tillage and increased cropping intensity, such as NT with CW, compared with traditional practice, such as CT with W-F system, and the content can be similar to that in CRP planting.
  • Authors:
    • Girija,A.
    • Khan,I. A.
    • Ramakrishna,Y. S.
    • Chary,G. R.
    • Vittal,K. P. R.
    • Sankar,G. R. M.
  • Source: Indian Journal of Dryland Agricultural Research and Development
  • Volume: 21
  • Issue: 2
  • Year: 2006
  • Summary: Sustainability indices of agricultural practices so far are developed independent of climatic effects. Especially under dry farming, the effect of rainfall is so overwhelming on the crop performance that this factor cannot be ignored while assessing for sustainability. In view of this, any sustainability index should be made independent of rainfall effect. Hence, a statistical measure of sustainability index 'eta', which is a function of estimate of error 'sigma' derived from a regression of yield through rainfall was developed. The 'eta' is a ratio between difference of mean and standard error (detrended for rainfall) to the maximum recorded yield during the period. Thus the limits of 'eta' are -1 to +1. The proposed procedure was utilized to arrive at sustainable practices from the data of All India Coordinated Research Project for Dryland Agriculture (India) field experiments conducted at both research station and on-farm from varying agroclimatic regions. The practices exceeding a sustainability yield index of 0.67 were considered as suitable for recommendation. The study indicated that barley, pearl millet, mustard, green gram, moth bean and cowpea had a moderate sustainability in arid conditions. Pearl millet at Akola (Maharashtra), pigeonpea and soybean at Indore (Madhya Pradesh) under wet semiarid conditions, and maize and horse gram at Arjia under dry semiarid conditions attained a moderate sustainability. Black gram, lentil and chickpea at Rewa (Madhya Pradesh), and lentil at Varanasi (Uttar Pradesh) also had moderate sustainability under dry subhumid conditions. A classification of superior genotypes of crops based on yield and sustainability and their variation under different climatic situations was made for cereals, pulses, oilseeds and vegetable and other crops. A grouping has also been made based on the variation of yield. Sustainability under different soils and climates and superior genotypes are identified. Some of the highly sustainable genotypes were Vandana of rice at Faizabad (Uttar Pradesh), RR-347-167 of rice at Ranchi, HUR-1095 of rice at Varanasi, BAU-2K-15 of linseed at Ranchi (Bihar), local variety of linseed at Rewa, AT-81 variety of sesame at Rajkot (Gujarat), HG-563 variety of cluster bean at Hisar (Haryana), S-1635 variety of mulberry at Bijapur (Karnataka) and SH-5 of sunn hemp at Hisar.
  • Authors:
    • Halvorson, A. D.
    • Reule, C. A.
  • Source: Agronomy Journal
  • Volume: 98
  • Issue: 5
  • Year: 2006
  • Summary: Irrigated, no-till (NT) production systems can potentially reduce soil erosion, fossil fuel consumption, and greenhouse gas emissions compared with conventional till (CT) systems. Including a legume in the rotation may also reduce N fertilizer requirements. Nitrogen fertilization (6 N rates) effects on irrigated, corn (Zea mays L.) and soybean [Glycine mar (L.) Merr.] yields in a corn-soybean rotation were evaluated for 5 yr on a clay loam soil to determine the viability of an irrigated NT system and N needs for optimum crop yield. Corn grain yields were significantly increased by N fertilization each of 3 yr in the rotation, but soybean grain yields (2 yr) did not respond to N fertilization, averaging 2.79 Mg ha(-1). Three year average corn grain yields were near maximum with an available N (AN) (soil + fertilizer + irrigation water N) level of 257 kg N ha(-1). Nitrogen use efficiency (NUE) by corn and soybean, based on grain N removal, decreased with increasing AN level and ranged from 155 to 46 and 88 to 18 kg grain kg(-1) AN for the low and high N treatments for corn and soybean, respectively. Estimated total N required to produce one Mg grain at maximum yield averaged 20 kg N for corn and 54 kg N for soybean. Corn residue increased with increasing N rate, but soybean residue was constant across N rates. Excellent irrigated, NT corn yields were obtained in this corn-soybean rotation for northern Colorado, but soybean yields were only marginally acceptable. Short soybean plant height (30-40 cm) and shattering made combine harvest difficult resulting in significant grain loss. Improved soybean cultivars are needed for this area to make a corn-soybean rotation a viable production system.
  • Authors:
    • Waddell, J.
    • Caesar-Tonthat, T.
    • Lenssen, A.
    • Sainju, U. M.
  • Source: Soil Science Society of America Journal
  • Volume: 70
  • Issue: 2
  • Year: 2006
  • Summary: Sustainable management practices are needed to enhance soil productivity in degraded dryland soils in the northern Great Plains. We examined the effects of two tillage practices [conventional till (CT) and no-till (NT)], five crop rotations [continuous spring wheat (Triticum aestivum L.) (CW), spring wheat-fallow (W-F), spring wheat-lentil (Lens culinaris Medic.) (W-L), spring wheat-spring wheat-fallow (W-W-F), and spring wheat-pea (Pisum sativum L.)-fallow (W-P-F)], and a Conservation Reserve Program (CRP) on plant biomass returned to the soil, residue C and N, and soil organic C (SOC), soil total N (STN), and particulate organic C and N (POC and PON) at the 0- to 20-cm depth. A field experiment was conducted in a mixture of Scobey clay loam (fine, smectitic, frigid Aridic Argiustolls) and Kevin clay loam (fine-loamy, mixed, superactive, frigid Aridic Argiustolls) from 1998 to 2003 near Havre, MT. Mean annualized plant biomass returned to the soil from 1998 to 2003 was greater in W-F (2.02 Mg ha-1) than in W-L and W-W-F, regardless of tillage. In 2004, residue cover was greater in CW (60%) than in other rotations, except in W-W-F. Residue amount and C and N contents were greater in NT with CW (2.47 Mg ha-1 and 963 and 22 kg ha-1, respectively) than in NT with W-L and CT with other crop rotations. The POC at 0 to 5 cm was greater in W-W-F and W-P-F (2.1-2.2 Mg ha-1) than in W-L. Similarly, STN at 5 to 20 cm was greater in CT with W-L (2.21 Mg ha-1) than in other treatments, except in NT with W-W-F. Reduced tillage and increased cropping intensity, such as NT with CW and W-L, conserved C and N in dryland soils and crop residue better than the traditional practice, CT with W-F, and their contents were similar to or better than in CRP planting.