• Authors:
    • Hegde, M.
    • Kulkarni, K. A.
    • Lingappa, S.
  • Source: Indian Journal of Plant Protection
  • Volume: 31
  • Issue: 1
  • Year: 2003
  • Summary: A study was conducted during the 1997 and 1998 kharif seasons in Karnataka, India, to evaluate the impact of intercrops on the conservation of Chrysoperla carnea and other natural enemies in the cotton ecosystem. Cotton hybrid (DCH-32) was grown alone (monocrop) or intercropped with cowpea, soyabean, groundnut, sorghum, chilli and lucerne. The average population of C. carnea and spiders were significantly high on cotton intercropped with lucerne, cowpea, and groundnut. The parasitization of bollworm egg and larvae were significantly high on cotton intercropped with sorghum and lucerne. Among the intercrops tested, lucerne conserved overall high natural enemy populations, while the natural enemy populations were least on cotton intercropped with soyabean. Similarly, the pest load was low on cotton grown in intercropping systems except with soyabean. Significantly higher number of good opened bolls (GOB) and seed cotton yield were harvested from cotton intercropped with lucerne. Cotton intercropped with groundnut and cowpea performed equally better and was at par with cotton intercropped with lucerne. However, intercropping with sorghum recorded the least number of GOB and seed cotton yield.
  • Authors:
    • Pringle, H. C.,III
    • Martin, S. W.
  • Source: Journal of Cotton Science
  • Volume: 7
  • Issue: 4
  • Year: 2003
  • Summary: Deep tillage at a 45 angle has been a recommended practice since the mid-1970s on most Mississippi Delta cotton soils. This practice disrupts hard pans and allows deeper wetting of the soil profile with winter rainfall. The newest deep tillage "subsoiler" designs (Paratill, low-till parabolic) have the shank extending through the soil at an angle, thereby reducing soil surface disturbance and allowing the subsoiler to run under the row in the direction of the row, without the shank passing directly through the drill. Both centre pivot and furrow irrigation of cotton has expanded since the early 1980s. With intermittent rainfall, irrigation is supplemental and represents a type of insurance against yield uncertainty during extended periods of water deficit. Field experiments were conducted at Stoneville, Mississippi, USA, during 1994-2001, to determine the long-term effects of sprinkler irrigation and in-row subsoil tillage on cotton yield and economic return of cotton cultivars DES119 (1994-95), SG125 (1996-99) and SG747 (2000-01) on silt loam soil from 1994 to 2001. In-row subsoil tillage was performed with a low-till parabolic subsoiler and irrigation was applied with an overhead lateral-move sprinkler irrigation system. Production costs were calculated for direct costs and total specified costs excluding land rent, general farm overheads and returns to management. Average net returns were calculated as the difference between income at the cotton loan rate of $1.15 per kg of lint and total specified costs. Returns were maximized with either the irrigated, non-subsoiled or the non-irrigated, subsoiled environments. Lower returns occurred in the irrigated, subsoiled environment due to the higher costs and lack of yield increase.
  • Authors:
    • Beghin, J. C.
    • Fang, C.
  • Source: Agricultural trade and policy in China: issues, analysis and implications
  • Year: 2003
  • Summary: This chapter assesses the protection and comparative advantage of China's major agricultural crops in six regions, using a modified Policy Analysis Matrix and 1997-2000 data. The following commodities are considered: early indica rice, late indica rice, japonica rice, wheat, maize, sorghum, soyabean, rapeseed, cotton, tobacco, sugarcane, and a subset of fruits and vegetables. The results suggest that, with the exception of high quality rice, the production of grains and oilseeds tends to suffer from a lack of comparative advantage over other crops in China, such as fruit and vegetables, tobacco and cotton. Further, it is concluded that grain self-sufficiency policies reduce allocative efficiency several-fold.
  • Authors:
    • Anand, K. V.
    • Katyal, V.
    • Gangwar, B.
  • Source: Indian Journal of Agricultural Science
  • Volume: 73
  • Issue: 9
  • Year: 2003
  • Summary: An experiment was conducted in Akola, Parbhani and Rahuri, Maharashtra, India to evaluate the productivity of various cropping sequences. In Akola (1987-88 to 1997-98) representing Vidharbha zone, the cropping sequence involving upland cotton ( Gossypium hirsutum)-groundnut ( Arachis hypogaea) was the most suitable and efficient, resulting in the highest grain-equivalent yield (10 079 kg ha -1 year -1), productivity (43.82 kg day -1 ha -1 wheat grain equivalent), profitability (49 539 rupees ha -1 year -1), economic efficiency (135.7 rupees day -1 ha -1) and land use efficiency (90.0%), and good benefit:cost ratio (16.57) and stability (0.68). However, in terms of energetics, soyabean ( Glycine max)-groundnut sequence was superior. In Central Maharashtra Plateaux Zone, cotton-groundnut sequence was also identified as the most efficient based on an 8-year study at Parbhani (1990-91 to 1997-98). This sequence gave the highest yield (12 060 kg ha -1 year -1 wheat grain equivalent), productivity (50.04 kg day -1 ha -1), profitability (62 053 rupees ha -1 year -1), economic efficiency (170.0 rupees day -1 ha -1) and land use efficiency (85%), with moderate system stability (0.59). In terms of energetics, soyabean-Indian mustard ( Brassica juncea) was superior. At Rahuri, representing western Maharashtra scarcity zone, sole sugarcane recorded the highest net return (93 429 rupees ha -1 year -1), economic efficiency (255.9 rupees ha -1 day -1) and benefit:cost ratio (19.96). Sorghum ( Sorghum bicolor)-cabbage ( Brassica oleracea var. capitata)-cowpea ( Vigna unguiculata) was equally profitable for fodder, resulting in a wheat grain yield equivalent of 22 793 kg ha -1 year -1, productivity of 94.2 kg day -1 ha -1, profitability of 81 733 rupees ha -1 year -1, economic efficiency of 223.9 rupees day -1 ha -1, and carbohydrate production of 4.69 g 10 6/ha.
  • Authors:
    • Jones, R. H.
    • Leonard, B. R.
    • Gore, J.
  • Source: Environmental Entomology
  • Volume: 32
  • Issue: 1
  • Year: 2003
  • Summary: Field and laboratory studies evaluated the influence of selected crop hosts on Helicoverpa zea population dynamics in relation to genetically engineered Bt (Bollgard) and non-Bt cottons. Host specific H. zea colonies were initiated with a colony originally collected from sweetcorn. The colony was allowed to complete one generation on meridic diet then split into cohorts and allowed to complete one generation on field maize, grain sorghum, soyabean, cotton, or meridic diet in individual 29.5 ml plastic cups. During the first part of the study, larval developmental times, pupal weights, and survival were measured. H. zea survival was higher on meridic diet and grain sorghum than on soyabean and cotton. The development of H. zea larvae was faster on field maize than the other larval diets. Also, H. zea required a longer period of time to complete development on cotton than on the other hosts. Pupal weights were higher on meridic diet than the plant hosts. Pupal weights of H. zea that completed larval stadia on cotton were lower than on the other larval diets. Neonates (F 1) from each of the host specific colonies (200 per colony) were exposed to Bt and non-Bt cottons. Mortality of second generation H. zea on non-Bt and Bt cottons was measured at 96 h. H. zea larvae from the cotton colony had higher mortality on non-Bt cotton than the other host specific colonies except the grain sorghum colony. On Bt cotton, larvae from the maize colony had a higher level of mortality than larvae from the soyabean and grain sorghum colonies. These data provide valuable information for evaluating the contribution of cultivated hosts as additional, alternative refugia in Bt-cotton resistance management plans.
  • Authors:
    • Rozelle, S.
    • Hu, R.
    • Huang, J.
    • Pray, C. E.
  • Source: The Plant Journal
  • Volume: 31
  • Issue: 4
  • Year: 2002
  • Summary: Bt cotton is spreading very rapidly in China, in response to demand from farmers for technology that will reduce both the cost of pesticide applications and exposure to pesticides, and will free up time for other tasks. Based on surveys of hundreds of farmers in the Yellow River cotton-growing region in northern China in 1999, 2000 and 2001, over 4 million smallholders have been able to increase yield per hectare, and reduce pesticide costs, time spent spraying dangerous pesticides, and illnesses due to pesticide poisoning. The expansion of this cost-saving technology is increasing the supply of cotton and pushing down the price, but prices are still sufficiently high for adopters of Bt cotton to make substantial gains in net income.
  • Authors:
    • Delaney, D. P.
    • Reeves, D. W.
  • Source: E. van Santen (ed.) 2002. Making Conservation Tillage Conventional: Building a Future on 25 Years of Research. Proc. of 25th Annual Southern Conserva­tion Tillage Conference for Sustainable Agriculture. Auburn, AL, 24-26 June 2002. Special Report no. 1.
  • Year: 2002
  • Summary: Intensive cropping and conservation tillage can increase soil organic C (SOC) and improve soil quality, however, economic reality often dictates cotton ( Gossypium hirsutum) monoculture. We conducted a study on a Compass loamy sand (coarse-loamy, siliceous, subactive, thermic Plinthic Paleudults) from 1998-2001 to compare an intensive conservation cropping system to standard cotton production systems used in the southeastern USA (Alabama). The system uses sunn hemp ( Crotalaria juncea) and ultra-narrow row (UNR; 8-inch drill) cotton in a rotation with wheat ( Triticum aestivum) and maize ( Zea mays). The standard systems used continuous cotton (both standard 40-inch rows and ultra-narrow row) and a maize-cotton rotation with standard row widths. A cover crop mixture of black oat ( Avena strigosa [ A. nuda])/rye ( Secale cereale) was used in all systems preceding cotton and a white lupin ( Lupinus albus)/crimson clover ( Trifolium incarnatum) mix was used before maize in the maize-cotton and intensive system. All systems were tested under conservation and conventional tillage in a split plot design of four replications; main plots were cropping systems and subplots were tillage. We used extension budgets to calculate net returns over variable costs and determined C balance of all residues returned to the soil. At the end of the experiment, soil C was determined by dry combustion (0-0.4, 0.4-2, 2-4, 4-8, and 8-12 in depths). Cropping system had a more consistent effect on cotton yield than tillage system. Four-year average lint yields were 872, 814, 711 and 663 lbs acre -1 for continuous UNR, intensive, maize-cotton, and continuous 40-in cotton systems, respectively. The UNR systems with conservation tillage had the highest net returns ($105 acre -1 year -1 (continuous) and $97 acre -1 year -1 (intensive)) while the conventional tillage continuous 40-in system had the lowest returns ($36 acre -1 year -1). Conservation tillage increased SOC concentration in the top 2 inches of soil 46% compared to conventional tillage. Cropping system affected SOC levels to the 4-in depth and the maize-cotton rotation resulted in the lowest SOC levels of all systems. Results suggest that small grain cover crops and wheat for grain in the intensive system were the dominate factor in SOC changes. For these drought-sensitive soils, UNR cotton production systems with conservation tillage and small grain cover or cash crops have the potential to rapidly increase soil organic matter; improving soil productivity and enhancing economic sustainability of cotton production in the southeastern USA.
  • Authors:
    • Reeves, D. W.
    • Burmester, C. H.
    • Motta, A. C. V.
  • Source: Making Conservation Tillage Conventional: Building a Future on 25 Years of Research. Proceedings of 25th Annual Southern Conservation Tillage Conference for Sustainable Agriculture, Auburn, AL, USA, 24-26 June, 2002 - Special Report no. 1, Alabama Agricult
  • Year: 2002
  • Summary: A replicated cotton (Gossypium hirsutum) rotation experiment has been conducted for 22 years (1980-2001) on a Decatur silt loam (fine, kaolinitic, thermic, Rhodic Paleudults) in the Tennessee Valley of northern Alabama, USA. The highly productive soil with little disease and nematode problems resulted in cotton yield increases from rotations of generally less than 10% during the first 15 years of the study. A switch to no-tillage in all rotations except continuous cotton in 1995 greatly improved cotton yield response to rotations. From 1995 to 2001 cotton yield increases to rotation have averaged between 5% and 18%. In this study, yield increases due to rotations seem linked to increases in soil organic matter and consequent improvements in soil quality. From 1979 to 1994 using conventional tillage, the only rotation that produced a greater than 10% yield increase was cotton rotated with wheat ( Triticum aestivum) and double-cropped soyabean ( Glycine max). This rotation was also the only rotation that significantly increased organic matter levels under conventional tillage. From 1995 to 2001, all rotations were no-tilled and the greater yield increases to rotations can also be associated with higher soil organic matter levels. Wheat as a grain rotation or cover crop often produced the greatest yield increases to the following cotton crop. Under conventional tillage the wheat residue provided increased organic matter residue. With no-tillage the wheat cover crop reduced surface soil compaction. No-tillage and rotations that increased residue production were linked to increased cotton yields on this soil.
  • Authors:
    • Spurlock, S. R.
    • Elmore, C. D.
    • Wesley, R. A.
  • Source: Agronomy Journal
  • Volume: 93
  • Issue: 1
  • Year: 2001
  • Summary: Deep tillage (subsoiling) of clayey soils in the fall when the profile is dry is a new concept that results in increased yields and net returns from soyabean (Glycine max) grown without irrigation. Crop rotation may also result in increased crop yields. Field studies were conducted on Tunica clay (clayey over loamy, smectitic, nonacid, thermic, Vertic Haplaquept) near Stoneville, Mississippi, USA (33degrees 26′ N lat), during 1993-97, to determine the individual and combined effects of fall deep tillage and crop rotations on crop yields and net returns. Treatments included monocrop cotton (Gossypium hirsutum cultivars DES 119 and Suregrow 125), soyabean (cultivars Pioneer 9592 and DPL 3588), and grain sorghum ( Sorghum bicolor cv. Pioneer 8333), and biennial rotations of cotton with grain sorghum and soyabean with grain sorghum grown without irrigation and in either a conventional-till (CT) or deep-till (DT) production system. Yields from all cotton and soyabean crop sequences grown in the DT respectively averaged 541 kg ha -1 and 525 kg ha -1 greater than comparable cotton (2184 kg ha -1) and soyabean (2983 kg ha -1) crop sequences grown in the CT. Net returns from monocrop cotton ($552 ha -1) and soyabean ($462 ha -1) in the DT respectively averaged $392 ha -1 and $121 ha -1 more than similar crop sequences in the CT. Rotations increased cotton and soyabean yields but not net returns because of the low value of the grain sorghum component. These data indicate that fall deep tillage should be incorporated into monocrop cotton and soyabean crop sequences to maximize and stabilize net returns from these crops on Tunica clay.
  • Authors:
    • Nyakatawa,E. Z.
    • Reddy,K. C.
  • Source: Agronomy Journal
  • Volume: 92
  • Issue: 5
  • Year: 2000
  • Summary: Inadequate and less vigorous crop stand is a constraint to adoption of conservation tillage in cotton (Gossypium hirsutum L.) production. We evaluated the effects of tillage (conventional till, mulch-till, no-till), cropping system (cotton-winter fallow, cotton-winter rye, Secale cereale L.), and N source and rate (ammonium nitrate and poultry litter; 0, 100, and 200 kg N ha(-1)) on rotten seedling emergence on a Decatur silt loam soil (Typic Paleudults) in northern Alabama, from 1996 to 1998. Cotton seedling counts under no-till were 40 to 150% greater than those under conventional till at 1 and 2 d during seedling emergence. Cotton-winter rye cropping system had 14 to 50% greater seedling counts than cotton-winter fallow cropping during the first 4 d of emergence in 1998. Poultry litter source of N gave 17 to 50% greater cotton seedling counts than ammonium nitrate during the first 4 d of emergence in 1998, In all these cases, the differences progressively narrowed down by the 4th day of seedling emergence. Cotton seedling counts were significantly correlated to cotton growth parameters and lint yield, especially in the drier year (1998). These results were attributed to soil moisture conservation during seedling emergence. Our results show that conservation tillage improved cotton germination, emergence, dry matter, and lint yield. Therefore, no-till with winter rye cover cropping and poultry litter can be used for achieving early cotton seedling emergence and growth in the U.S. cotton belt where dryland cotton production systems are on the increase and safe disposal of poultry litter is becoming an environmental problem.