• Authors:
    • Kelley, J.
    • Oliver, D.
    • Gbur, E. E.
    • Brye, K. R.
    • Amuri, N.
  • Source: Weed Science
  • Volume: 58
  • Issue: 3
  • Year: 2010
  • Summary: Management practices and cropping systems that serve as integrated weed management practices, and at the same time can contribute to improved soil quality, will be important for the sustainability of agricultural production systems. The objective of this study was to assess weed species population density under contrasting tillage (conventional tillage [CT] and no tillage [NT]), residue burning (burn and no burn), and residue level (low and high) treatments after 5 and 6 yr of consistent management in a wheat-soybean double-crop production system. A field experiment was conducted from fall 2001 to fall 2007 in the Mississippi River Delta region of eastern Arkansas on a Calloway silt-loam. Weed assessments were conducted twice during the soybean growing season, before (early season) and after herbicide application (late season) in 2006 and 2007. Total weed density was greater under CT (513 plants m(-2)) than under NT (340 plants m(-2)) early in the growing season in 2006, but was greater under NT than CT late in the season in 2007, suggesting that the effectiveness of glyphosate on total weeds differs between CT and NT. Averaged across residue levels, grass species density was greatest in the NT burn (68 to 167 plants m(-2)) combination and lowest in the NT no-burn (41 to 63 plants m(-2)) early in the growing season in both years. Broadleaf density was greater early (200 to 349 plants m(-2)) than late (18 to 20 plants m(-2)) in the growing season under both CT and NT in 2006, but in 2007 broadleaf density did not differ by tillage treatment between seasons. Perennial weed density was greater in the burn (99 plants m(-2)) than in the no-burn (59 plants m(-2)) treatment in 2006. No tillage, no burning, and a high residue level appeared to contribute to the suppression of most weed species without reducing herbicide efficiency.
  • Authors:
    • Basso, F. C.
    • Montanari, R.
    • Passos e Carvalho, M. de
    • Andreotti, M.
    • Pariz, C. M.
    • Azenha, M. V.
    • Vercese, F.
  • Source: Ciência Rural
  • Volume: 40
  • Issue: 3
  • Year: 2010
  • Summary: The variation and the spatial dependence attributes of the following plant and soil characteristics: soyabean yield (SY) in no-till and irrigated soil; the macroporosity (MA); microporosity (MI); total porosity (TP); and bulk density (BD), in depths of 1 (0-0.10 m), 2 (0.10-0.20 m) and 3 (0.20-0.30 m), were studied in a Red Latosol of Mato Grosso do Sul, Brazil, were analysed during 2004/05, to study the variation and the linear and spatial correlations among the attributes (plant and soil) and select an index of soil physical quality with good capacity to represent the soyabean yield. A geostatistical grid to collect soil and plant data was installed, with 124 sample points, in an area of 4000 m 2. The linear relationship between soyabean yield and physical attributes of soil studied was low. So, there was a direct spatial relationship between SY and MA1 (0-0.10 m), as well as between SY and MA2 (0.10-0.20 m). The MA1 showed its best index of the soil physical quality, when it was destined to estimate the soyabean yield in no-till soil.
  • Authors:
    • Bartosik, R.
  • Source: Julius-Kühn-Archiv
  • Issue: 425
  • Year: 2010
  • Summary: Concerning grain production, South America is divided in two main regions: (1) the Mercosur region (Argentina, Brazil, Uruguay and Paraguay) which produces more than 250 million tonnes of grains and oilseeds, and (2) the Andes Mountain region countries, which are net importers of these products. The main challenges related to grain postharvest that South America is facing are to minimize the quality and quantity losses; improve the food safety; enhance the capability for segregation and traceability of identity preserved (IP) grains; and incorporate technology to maintain the overall efficiency of the postharvest system. Among the critical points affecting the efficiency of the system are the shortage of permanent storage capacity; large storage structures which affects the segregation of IP grains; deficient transportation system (roads and railroads); poor management of integrated pest control system; and unsatisfied demand of formal and informal education in suitable grain postharvest technologies and practices. However, the region remains highly competitive in producing and delivering food for the rest of the world and it has demonstrated high capacity for incorporating cost efficient grain handling technologies. As a result, one of the main changes in the region was the appearance of the silobag system for temporary storage of dry grain and oilseeds. Each silobag can hold approximately 200 tonnes of wheat and with the available handling equipment is quite simple to load and unload. During the 2008 harvest season, more than 33 million tonnes of grain were stored in these plastic bags in Argentina (including corn, soybean, wheat, sunflower, malting barley, canola, cotton seed, rice, lentils, sorghum, beans and even fertilizers). The silobag technology is also being adopted not only in neighbor countries, but also in countries around the world such as the USA, Mexico, South Africa, Australia, Russia and Ukraine, among others.
  • Authors:
    • Frederick, J. R.
    • Fortnum, B. A.
    • Bauer, P. J.
  • Source: Agronomy Journal
  • Volume: 102
  • Issue: 4
  • Year: 2010
  • Summary: Longer rain-free periods are predicted to occur more often in the southeastern United States as a result of global climate change. This nonirrigated field study was conducted from 1997 through 2002, which coincided with the 1998-2002 drought that affected most of the United States. The objective was to determine the effect of rotation and tillage on cotton (Gossypium hirsutum L.) productivity. Treatments in the study were rotation [cotton rotated with corn (Zea mays L.), cotton planted after a rye (Secale cereale L.) winter cover crop, and continuous cotton with no cover crop] and tillage system (conventional tillage and conservation tillage). Two levels of aldicarb [2-methyl-2-(methylthio)propanal O-{(methylamino)carbonyl}oxime] (0 and 1.18 kg a.i. ha(-1)) were also included because of known soil management effects on thrips (Frankliniella sp.) and root-knot nematodes (Meloidigyne incognita). The predominant soil types were Bonneau loamy sand (loamy, siliceous, subactive, thermic Arenic Paleudult) and Norfolk loamy sand (fine-loamy, kaolinitic, thermic Typic Kandiudult). Rotation did not affect cotton yield in any year. Tillage did not affect cotton yield in 1997. Conservation tillage resulted in an average 25% yield increase in cotton lint yield over conventional tillage during the 5-yr drought. Tillage and aldicarb affected both thrips and root-knot nematodes, but lack of interaction among these factors for lint yield suggested that management of these pests was not the predominant cause for the cotton yield increase with conservation tillage. Conservation tillage for cotton production could be an important method to help mitigate the effects of climate change in the region if change occurs as predicted.
  • Authors:
    • McSorley, R.
    • Bhan, M.
    • Chase, C. A.
  • Source: Nematropica
  • Volume: 40
  • Issue: 1
  • Year: 2010
  • Summary: Two field experiments were initiated in summer 2006 in north-central Florida to compare the effects of integrating cover crops, living mulches, and intercropping on plant-parasitic nematode populations, as well as the effect of fall and spring vegetables on the multiplication rate of root-knot nematodes. Treatments consisted of seven organic cropping systems that included a summer cover crop followed by fall and spring vegetables. The summer cover crop included: pearl millet (Pennisetum glaucum), sorghum sudangrass (Sorghum bicolor x S. bicolor var. sudanense), sunn hemp (Crotalaria juncea), velvetbean (Mucuna pruriens var. pruriens), weedy fallow, mixture of pearl millet-sunn hemp, and mixture of sorghum sudangrass-velvet bean. One experiment utilized fall yellow squash (Cucurbita pepo) and spring bell pepper (Capsicum annuum) as vegetable crops, and fall broccoli (Brassica oleracea) and spring sweet corn (Zea mays) were used in the other experiment. Nematode populations were monitored at the end of the cover crop and vegetable seasons. Summer cover crops of sorghum-sudangrass or pearl millet increased root-knot nematode (Meloidogyne incognita) population levels in some instances while sunn hemp suppressed it in the broccoli-sweet corn experiment. The multiplication rate of root-knot nematodes was lowest when broccoli was planted in the cropping system. Systems with sorghum-sudangrass (alone or in mixture) increased population densities of ring (Mesocriconema spp.) and lesion (Pratylenchus spp.) nematodes, and occasionally increased stubby-root nematodes (Paratrichodorus spp.). Cover crops that increased nematode numbers when planted alone usually gave the same result when planted in mixtures with another cover crop. Other cropping systems failed to suppress plant-parasitic nematodes but maintained low densities similar to weedy fallow.
  • Authors:
    • Balasubramanian, A.
    • Lakshmi, K. V.
    • Sankaran, N.
  • Source: Madras Agricultural Journal
  • Volume: 96
  • Issue: 1-6
  • Year: 2009
  • Summary: A field experiment was conducted during North East Monsoon season of 2002 and 2003 at Tamil Nadu Agricultural University, Coimbatore to study the productive and economically viable integrated rainwater and nitrogen management practice for dryland maize under different rainfall situations. It is concluded that for early withdrawal of rainfall around 45 DAS, two supplemental irrigations given at tasseling and silking stages through run off recycling from farm pond increased growth, yield parameters, grain yield by 134 percent and net returns by Rs.3389 ha -1 over rainfed maize in 2002. For moisture stress at tasseling and soft dough stages, two supplemental irrigation increased growth, yield attributes, grain yield by 88 percent and net return by Rs. 3305 ha -1 over rainfed maize in 2003. Application of 40 kg N ha -1 with intercropping and incorporation of either sunnhemp or cowpea at 45 DAS increased yield and net returns of maize over sole maize with out inorganic nitrogen.
  • Authors:
    • Abrol, V.
    • Sankar, G.
    • Singh, B.
    • Sharma, P.
  • Source: Indian Journal of Agricultural Sciences
  • Volume: 79
  • Issue: 11
  • Year: 2009
  • Summary: A Field experiment was conducted during 2005-06 and 2006-07 at Dryland Research Sub Station, Dhiansar to study the influence of tillage and mulching practices on crop productivity, economics and soil properties of maize-wheat system under rainfed situation. Four different tillage methods, viz conventional, minimum, no tillage and raised bed were used in the main plots and four different mulch materials, viz straw, polyethylene, soil mulch including no mulch were used in the sub-plots. Tillage practices significantly influenced the yield of maize and wheat. Grain yield of maize and wheat was statistically at par in conventional and minimum tillage system and significantly higher than no tillage system in both the years. Mulching also resulted in increased in yield. Significantly higher mean grain yield of maize (1.91 tonnes/ha) and wheat (0.63 tonnes/ha) was recorded from polyethylene mulch, followed by straw mulch (1.77 tonnes/ha, 0.61 tonnes/ha) respectively. Minimum tillage and polyethylene mulch or straw mulch conserve more moisture and infiltration rate than other tillage methods and mulch application. The highest mean net returns (Rs 10 078) and benefit:cost ratio (1.28) was obtained with minimum tillage and lowest with conventional tillage (Rs 8 631 0.90). Minimum tillage in conjunction with polyethylene mulch or straw mulch was economically profitable and improve, the crop production and soil quality for maize-wheat sequence in rainfed condition.
  • Authors:
    • Peeyush, S.
    • Vikas, A.
    • Shankar, G.
  • Source: Research on Crops
  • Volume: 10
  • Issue: 3
  • Year: 2009
  • Summary: A field experiment was conducted during 2005-06 and 2006-07 at Dryland Research Sub-Station, Dhiansar to study the influence of tillage and mulching management on soil physical and chemical properties and crop yield on maize-wheat system under rainfed situations. Maize and wheat yield was statistically at par in conventional and minimum tillage and significantly higher over control. Increase in bulk density was higher in conventional tillage as compared to the minimum tillage. Reduction in infiltration rate was 17.24% higher in conventional tillage than minimum tillage. Minimum tillage improved the net return, benefit:cost ratio as well as fertility status. Application of plastic mulch resulted in maximum grain yield, infiltration rate and nutrient status than no mulch.
  • Authors:
    • Raper, R. L.
    • Siri-Prieto, G.
    • Reeves, D. W.
  • Source: Agronomy Journal
  • Volume: 101
  • Issue: 6
  • Year: 2009
  • Summary: The use of crop rotation systems involving winter-annual grazing can help peanut (Arachis hypogaea L.) producers increase profitability, although winter-annual grazing could result in excessive soil compaction, which can severely limit yields. We conducted a 3-yr field study on a Dothan loamy sand in southeastern Alabama to develop a conservation tillage system for integrating peanut with winter-annual grazing of stocker cattle under dryland conditions. Winter-annual forages and tillage systems were evaluated in a strip-plot design, where winter forages were oat (Avena sativa L.) and annual ryegrass (Lolium mutiflorum L.). Tillage systems included moldboard and chisel plowing, and combinations of noninversion deep tillage (none, in-row subsoil, or paratill) with/without disking. We evaluated soil water content, peanut leaf stomatal conductance, plant density, peanut yield, peanut net return, and total system annual net return. Peanut following oat increased soil water extraction (15%), stands (12%), and yields (21%) compared with peanut following ryegrass. Strict no-till resulted in the lowest yields (2.29 Mg ha(-1), 42% less than the mean) and noninversion deep tillage (especially in-row subsoil) was required to maximize water use and yields with conservation tillage. Net return from annual grazing ($185 ha(-1), USD) represented 40% of the total return for the best treatment (no-tillage with in-row subsoil following oat = $462 ha(-1)). Integrating winter-annual grazing in this region using noninversion deep tillage following oat in a conservation tillage system can benefit peanut growers, allowing extra income without sacrificing peanut yields.
  • Authors:
    • Jyoti, K.
    • Tarunvir, S.
  • Source: Agricultural Situation in India
  • Volume: 66
  • Issue: 7
  • Year: 2009
  • Summary: This study examines the cost and returns of dry land maize in the Jammu District of Jammu and Kashir state in India; the resource use efficiency and estimates the extent of instability in cropped area, yield and net returns.