• Authors:
    • Shivani
    • Mishra, S.
    • Singh, V.
    • Sanjeev, K.
  • Source: Indian Journal of Agricultural Sciences
  • Volume: 76
  • Issue: 9
  • Year: 2006
  • Summary: A field experiment was conducted in Bihar, India during the winter of 2002-04 to determine the effects of irrigation and tillage on the soil-water-plant relationship and productivity of maize cv. Deoki. The treatments included disc ploughing + 2 harrowing + planking (T1), 2 cultivator + planking (T2), rotavator (T3) and zero-till planter (T4), in combination with 3 irrigations during the pre-knee height of the crop (30 days after sowing (DAS)), knee height and silking stages (I1), I1 + irrigation during the milking stage (I2), irrigation during the pre-knee height, knee-height, tasseling, milking and grain filling stages (I3) and irrigation during the pre-knee height, knee height, tassel initiation, silking, milking and grain filling stages (I4). The physical properties of the soil of rotavator-tilled plots recorded higher bulk density (1.33 and 1.30 mg/m 3), soil strength (2.10 and 2.05 MPa), infiltration rate (0.420 and 0.432 cm/ha) and porosity (49.81 and 50.94%) during 2002-03 and 2003-04, respectively. Plant height (189.33 and 190.07 cm), leaf area index (2.673 and 2.728) dry matter accumulation (369.77 and 392.78 g) and relative leaf water content (94.61 and 93.36%) were highest with rotavator tilling during 2002-03 and 2003-04. Plants receiving 5-6 irrigations exhibited superior crop yield and yield attributes. Rotavator-tilled maize showed higher water expense efficiency compared to plants under different tillage systems. Rotavator tilled maize irrigated 5-6 times recorded the highest grain yield (5831 and 5960kg/ha) and net returns (Rs. 16 173 and Rs. 17 493) during 2002-03 and 2003-04, respectively.
  • Authors:
    • Sankar, G.
    • Vittal, K.
    • Chary, G.
    • Ramakrishna, Y.
    • Girija, A.
  • Source: Indian Journal of Dryland Agricultural Research and Development
  • Volume: 21
  • Issue: 1
  • Year: 2006
  • Summary: The data of 48 field experiments conducted during 1999 to 2003 under on-station conditions for assessing the tillage requirements of 5 cereals (rice, wheat, maize, pearl millet and finger millet), 2 oilseeds (groundnut and soyabean) and one pulse crop (cluster bean) under different soil and climatic conditions at 13 centres of All India Coordinated Research Project for Dryland Agriculture are presented. Based on the data generated from field experiments with conventional tillage, low tillage + hand weeding and low tillage + herbicide application, a detailed statistical assessment of superiority of tillage practices was conducted. Results indicated that conventional tillage was superior at Bangalore, Karnataka for finger millet under semiarid Alfisols; peal millet under semiarid Vertisols of Solapur, Maharashtra and arid Inceptisols of Agra, Uttar Pradesh; rice under moist subhumid Oxisols of Phulbani, Orissa and dry subhumid Inceptisols of Varanasi, Uttar Pradesh; maize under dry subhumid Inceptisols of Rakh Dhiansar, Jammu and Kashmir; wheat under moist subhumid Inceptisols of Ballowal Saunkhri, Punjab; and soyabean under semiarid Vertisols of Indore, Madhya Pradesh. Low tillage + herbicide application was found to be superior for rice under humid Oxisols of Ranchi, Jharkhand; maize under dry subhumid Inceptisols of Ballowal Saunkhri; soyabean under moist subhumid Vertisols of Rewa; and cluster bean under semiarid Aridisols of Dantiwada. LOw tillage + hand weeding was found to be superior for pearl millet under semiarid Aridisols of Hisar, Haryana and groundnut under semiarid Alfisols of Anantapur, Andhra Pradesh.
  • Authors:
    • Suryadi, M.
    • Nagai, N.
    • Siregar, M.
  • Source: CAPSA Working Paper
  • Issue: 98
  • Year: 2006
  • Summary: This report is the outcome of the second phase of the AGRIDIV project in Indonesia. The goal of this second phase study is to examine the performance of farming, marketing and processing of CGPRT crops at two dryland sites that have different cropping patterns. The two selected sites were Siswa Bangun and Restu Baru village. The results would by no means represent a national average. Hence, the description of farming, marketing and processing of those crops given here forms a source of in-depth quantitative and qualitative information that might have wider validity. Findings relate to maize and cassava commodity systems. Policy recommendations are presented.
  • Authors:
    • Hergert, G. W.
    • Tarkalson, D. D.
    • Cassman, K. G.
  • Source: Agronomy Journal
  • Volume: 98
  • Issue: 1
  • Year: 2006
  • Summary: Tillage systems and nutrient management influence soil chemical properties that can impact the long-term sustainability of dryland production systems. This study was conducted to compare the effects of no-till (NT) and conventional till (CT) on the soil chemical properties and grain yield of a dryland winter wheat ( Triticum aestivum L.)-grain sorghum [ Sorghum bicolor (L.) Moench]/corn ( Zea mays L.)-fallow rotation. The effects of tillage practice over a 27-yr period (1962-1989) and the effect of the conversion of CT to NT over a 14-yr period (1989-2003) on selected soil chemical properties [pH, cation exchange capacity (CEC), base saturation (BS), soil organic C (SOC), K, Ca, Mg, and Bray-P] at different soil depths was determined. The acidification rate of the NT treatment from 1962 to 2003 was also determined. The study was conducted at North Platte, NE on a Holdrege silt loam (fine-silty, mixed, mesic Typic Argiustolls). In 1989, there were differences in soil chemical properties between CT and NT at some depths after 27 yr. However, in 2003, 14 yr after converting from CT to NT, there were no differences in the soil chemical properties compared with continuous NT. In 1989 and 2003, the soil chemical properties varied with soil depth. The acidification rate from 1962 to 2003 for the NT treatment in the 0- to 15-cm depth was 1.3 kmol H + ha -1 yr -1. This rate of acidification represents 38% of the total potential acidity from N fertilizer applications over 41 yr. Acidification was attributed to nitrification of ammonium-based fertilizers and leaching of NO 3-. Long-term winter wheat (1966-1983) and grain sorghum (1964-1988) grain yields were higher for NT (2718 and 4125 kg ha -1) than CT (2421 and 3062 kg ha -1). Retention of soil moisture as a result of increased residue cover under NT likely contributed to higher NT yields. Soil chemical properties in the wheat-sorghum/corn-fallow rotation will likely continue to change as a result of current management practices. Lime additions may become necessary in the future to ensure the sustainability of crop production in this system.
  • Authors:
    • Cassman, K. G.
    • Hergert, G. W.
    • Payero, J. O.
    • Tarkalson, D. D.
  • Source: Plant and Soil
  • Volume: 283
  • Issue: 1-2
  • Year: 2006
  • Summary: Soil pH is decreasing in many soils in the semiarid Great Plains of the United States under dry land no-till (NT) cropping systems. This study was conducted to determine the rate of acidification and the causes of the acidification of a soil cropped to a winter wheat (Triticum aestivum L.)-grain sorghum [Sorghum bicolor (L.) Moench]/corn (Zea mays L.)-fallow rotation (W-S/C-F) under NT. The study was conducted from 1989 to 2003 on soil with a long-term history of either continuous NT management [NT(LT)] (1962-2003) or conventional tillage (CT) (1962-1988) then converted to NT [NT(C)] (1989-2003). Nitrogen was applied as ammonium nitrate (AN) at a rate of 23 kg N ha(-1)supercript stop in 1989 and as urea ammonium nitrate (UAN) at an average annual rate of 50 kg N ha(-1) from 1990 to 2003 for both NT treatments. Soil samples were collected at depth increments of 0-5, 5-10, 10-15, and 15-30 cm in the spring of 1989 and 2003. Acidification rates for the NT(LT) and NT(C) treatments were 1.13 and 1.48 kmol H+ ha(-1) yr(-1) in the 0-30 cm depth, respectively. The amount of CaCO3 needed to neutralize the acidification is 57 and 74 kg ha(-1) yr(-1) for the NT(LT) and NT(C) treatments, respectively. A proton budget estimated by the Helyar and Porter [1989, Soil Acidity and Plant Growth, Academic Press] method indicated that NO3- leaching from the 30 cm depth was a primary cause of long-term acidification in this soil. Nitrate leaching accounted for 59 and 66% of the H+ from the acid causing factors for NT(LT) and NT(C) treatments, respectively. The addition of crop residues to the soil neutralized 62 and 47% of the acidity produced from the leaching of NO3-, and 37 and 31% of the acid resulting from NO3- leaching and the other acid-causing constituents for the NT(LT) and NT(C) treatments, respectively. These results document that surface soils in dry land W-S/C-F rotations under NT are acidifying under current management practices. Improved management to increase nitrogen uptake efficiency from applied fertilizer would help reduce the rate of acidification. The addition of lime materials to prevent negative impacts on grain yields may be necessary in the future under current management practices.
  • Authors:
    • Wang, X.
  • Source: Conservation tillage and nutrient management in dryland farming in China
  • Year: 2006
  • Summary: This thesis contains 8 chapters focusing on the relations between rainfall and crop yields, and on the effects of various tillage and nutrient management practices on erosion, crop yields and water and nutrient use efficiencies. The bases of the study were: desk studies on conservation tillage and on dust storm erosion in China; long-term field experiments conducted in the dry semi-humid region of northern China (Shanxi and Henan); and simulation modelling. The first two chapters provide a brief introduction and background information on the trends in soil conservation and conservation tillage practices on global, national and regional scales, with emphasis on dryland farming of northern China. Chapter 3 analyses the effects of variation in rainfall on crop yields. The next chapter covers tillage and residue effects on rainfed wheat and maize production. Chapters 5 and 6 discuss nutrient dynamics in dryland maize cropping systems with emphasis on grain yield, and water and nutrient use efficiencies and on nutrient balances and soil fertility indices. Chapter 7 presents a scenario analysis of tillage, crop residue, cattle manure and fertilizer application management effects on soil organic carbon dynamics, using the Century model with input from the long-term field studies. The final chapter provides a general discussion and synthesis of the research findings. The consequences for future research and application of conservation tillage are also discussed.
  • Authors:
    • Acciaresi, H. A.
    • Zuluaga, M. S.
  • Source: Planta Daninha
  • Volume: 24
  • Issue: 2
  • Year: 2006
  • Summary: The use of narrow plant spacing in corn (Zea mays) has been suggested as a technological alternative to obtain grain yield increases, due to a better use of resources. The regular pattern could diminish intraspecific competition while favoring interspecific competition with weeds. The objective of this study was to analyze the effect of corn row spacing on weed aboveground biomass and corn grain yield. Field experiments were conducted during 2002/ 2003 and 2003/2004 growing seasons. Three corn hybrids with two-row width (0.70 and 0.35 m) were tested. A greater photosynthetic photon flux density (PPFD) interception with a lower weed aboveground dry matter in narrow row arrangement was obtained. Corn grain yield was greater in the narrow row arrangement than in the wide row spacing. This increase in grain yield was related to a better resource use that allows for a reduced interspecific competition. The use of reduced spatial arrangement appeared to be an interesting alternative to increase both the grain yield potential and corn suppressive ability against weeds in corn dryland production systems.
  • Authors:
    • Cantero-Martinez, C.
    • Westfall, D. G.
    • Sherrod, L. A.
    • Peterson, G. A.
  • Source: Journal of Soil and Water Conservation
  • Volume: 61
  • Issue: 2
  • Year: 2006
  • Summary: The presence of crop residue is an important component of dryland cropping systems management in the semiarid environment where soil erosion by wind is a major soil degradation process. Residue also affects precipitation capture and runoff. Long-term residue quantity dynamics of different cropping systems has not been studied in the semi-arid environment of the western Great Plains. Long-term studies were conducted in eastern Colorado, USA to determine the interaction of no-till cropping systems, soils, and climatic gradient on the production, retention, and disappearance of crop residue over a 12-year period. The cropping systems evaluated were winter wheat ( Triticum aestivum)-summer fallow (WF), winter wheat-maize ( Zea mays) or sorghum ( Sorghum bicolor)-summer fallow (WC/SF), winter wheat-maize/sorghum-millet ( Panicum miliaceum)-summer fallow (WC/SMF), and continuous cropping (CC). A soil surface residue base was achieved in a few years (four to five) and changed little over time. However, as cropping intensity increased the total crop residue retained on the soil surface increased as the proportion of fallow time decreased; a general trend was for residue levels to increase slowly. However, in the winter wheat-summer fallow system residue levels showed a trend to decrease after the initial base was achieved. Greater residue production and retention occurred on the toeslope soil position because these soils are deeper, have greater water holding capacity, and receive run-on water from upslope positions. Residue disappearance was less in the fallow period before maize planting compared to before wheat planting due to the greater fallow period, which included summer fallow in the wheat system. Residue loss was greater during the crop production periods as compared to the fallow periods. The levels of residue present on the soil surface in our intensive no-till cropping systems were generally adequate to control erosion by wind. However, at our high potential evapotranspiration site the residue levels were "marginal" for adequate wind erosion abatement, particularly in the winter wheat-summer fallow system. A combination of no-till management and increased cropping intensity (greater than winter wheat-summer fallow) is the key to sustainable production and soil conservation in this semi-arid environment.
  • Authors:
    • Valdes, G. S. B.
    • Lee, H. C.
    • Cook, H. F.
  • Source: Soil & Tillage Research
  • Volume: 91
  • Issue: 1-2
  • Year: 2006
  • Summary: Application of organic amendment to the soil surface is widely used in order to ameliorate topsoil physical conditions, especially with respect to temperature, evaporation and water content. Water intercepted by mulch and crop canopy involves loss through evaporation that never replenishes the soil water. In this study, hydrological and temperature conditions beneath mulches of manufactured materials, organic waste, wheat straw ( Triticum aestivum L.) and soybean straw ( Glycine max L. Merrill) applied at different thickness were investigated in glasshouse and field conditions in southern England. Interception loss by a maize ( Zea mays L.) canopy and mulch modified the soil water balance by adversely affecting soil water content beneath thicker application. Mulching had a beneficial effect on soil water and temperature regimes. These findings are important for identifying mulching practices for dryland agriculture and under scenarios of climatic change that predict lower rainfall and higher temperatures in summer.
  • 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.