• Authors:
    • Jat, M.
    • Sharma, S.
    • Balyan, J.
    • Sharma, R.
    • Jain, L.
  • Source: Current Agriculture
  • Volume: 31
  • Issue: 1/2
  • Year: 2007
  • Summary: A study was conducted at Dryland Farming Research Station, Arjia, Bhilwara during 1996 and 1997, to find out the tillage requirement for the maize, Seven tillage systems were evaluated for production of maize in kharif season. The tillage systems included were: A. Summer (T1 - Disc plough followed by cultivator, T2 - Cultivator followed by cultivator, T3 - Deshi plough followed by cultivator and T4 - Deshi plough followed by deshi plough), B. After pre monsoon (T5 - Disc plough followed by cultivator and T6 - Cultivator followed by cultivator) and C. At sowing (T7 - Cultivator followed by cultivator). The tillage system comprising of summer disc ploughing followed by cultivator was more beneficial as of this resulted in higher yield and net return supported by effective reduction in runoff, soil loss and increase water use efficiency for crops in the region. However, during good and low rainfall, for higher net return, there is a need of shift in tillage practices.
  • Authors:
    • Jia, H.
    • Ma, C.
    • Yang, Q.
    • Liu, Z.
    • Li, G.
    • Liu, H.
  • Source: Nongye Jixie Xuebao = Transactions of the Chinese Society for Agricultural Machinery
  • Volume: 38
  • Issue: 12
  • Year: 2007
  • Summary: The present status of dry farming in northern China was analyzed and a three-year rotation tillage method suitable for the ridged cultivation region of northeastern China and the techniques for efficient utilization of natural rainfall in the Loess Plateau region of northwestern China was put forward. The tests conducted in the northeast showed that stalk mulching increased the percentage of soil moisture content by 10% and the content of soil organic matter by 0.06 percentage point after three years, decreased the volume density of soil by 0.09 g/cm 3, chiseling increased the percentage of soil moisture content by 26.2%, and less tillage increased the percentage of soil moisture content by 3 percentage point. The tests conducted in the northwest showed that for winter wheat, the percentage of water storage increased by 18-5%; for spring corn, the percentage of soil moisture content increased by 30%. The stalk mulching tests for two years showed that the content of soil organic matter increased by 0.05%-0.1% and the content of total nitrogen increased by about 0.1 g/kg.
  • Authors:
    • Payero, J. O.
    • Schneekloth, J. P.
    • Klocke, N. L.
  • Source: Transactions of the ASABE
  • Volume: 50
  • Issue: 6
  • Year: 2007
  • Summary: Dwindling water supplies for irrigation are prompting alternative management choices by irrigators. Limited irrigation, where less water is applied than full crop demand, may be a viable approach. Application of limited irrigation to maize ( Zea mays) was examined in a study conducted at the West Central Research and Extension Centre of the University of Nebraska-Lincoln at North Platte, Nebraska, USA. Maize was grown in crop rotations with dryland, limited irrigation, or full irrigation management from 1985 to 1999. Crop rotations included maize following maize (continuous maize), maize following wheat ( Triticum aestivum), followed by soyabean ( Glycine max) (wheat-maize-soyabean), and maize following soyabean (maize-soyabean). Full irrigation was managed to meet crop evapotranspiration requirements (ETc). Limited irrigation was managed with a seasonal target of no more than 150 mm applied. Precipitation patterns influenced the outcomes of measured parameters. Dryland yields had the most variation, while fully irrigated yields varied the least. Limited irrigation yields were 80 to 90% of fully irrigated yields, but the limited irrigation plots received about half the applied water. Grain yields were significantly different among irrigation treatments. Yields were not significantly different among rotation treatments for all years and water treatments. For soil water parameters, more statistical differences were detected among the water management treatments than among the crop rotation treatments. Economic projections of these management practices showed that full irrigation produced the most income if water was available. Limited irrigation increased income significantly from dryland management.
  • Authors:
    • Zhang,X. C.
    • Liu,W. Z.
  • Source: Field Crops Research
  • Volume: 100
  • Issue: 2-3
  • Year: 2007
  • Summary: Matching fertilizer rates with available water supplies in water-scarce environments remains a major challenge for improving water use efficiency and crop yield. The objectives are to (i) develop a new approach to characterizing interrelations of yield ( Y), evapotranspiration (ET), water use efficiency (WUE), and soil fertility using an elasticity index, and (ii) to further derive optimal-coupling domains of water and fertilizer inputs using maize data of 1997 and 1998, as an example. The experiment was an incomplete factorial design with two factors (water supply and fertilizer input) with five levels each, and had a total of 13 treatments with three replicates each. A maize cultivar (Zhongdan 2, Zea mays L.) was grown in a loessial silt loam in the hilly region of the Loess Plateau of China. Irrigation was hand applied at predetermined amounts as needed, and fertilizers including nitrogen, phosphate, and yard manure were applied at planting and jointing at predetermined rates. Approaches on how to use the crop-water production function and elasticity index (EI) to characterize the interrelations of Y, ET, and WUE were presented, and further extended to derive the optimal-coupling domains of water and fertilizer inputs. Yield responses to water and fertilizer inputs followed a quadratic function with a positive interactive term. When constrained by local maximum yields, the optimal-coupling domain took a half-ellipse form with the global maximum WUE and Y (or maximum ET) corresponding to the left and right end points on its long axis. As water supply increased, WUE reached its maximum before yield did. If water supply is limiting, fertilizer rates that maximize WUE rather than yield should be used; otherwise, seeking maximum yield may be desirable. For irrigation management, total water supply to maize should not exceed 550 mm in the region. Furthermore, the optimal domain can be used to determine optimal fertilizer rates for any given water supply, which may be estimated from seasonal climate forecasts in the case of dryland farming or based on available water supply for future irrigation. For a given water supply, fertilizer rates should be between the rate of reaching local maximum WUE and the rate of reaching local maximum yield.
  • Authors:
    • Radford, B. J.
    • Yule, D. F.
    • McGarry, D.
    • Playford, C.
  • Source: Soil & Tillage Research
  • Volume: 97
  • Issue: 2
  • Year: 2007
  • Summary: Heavy wheel traffic causes soil compaction, which adversely affects crop production and may persist for several years. We applied known compaction forces to entire plots annually for 5 years, and then determined the duration of the adverse effects on the properties of a Vertisol and the performance of maize and sorghum crops under no-till dryland cropping with residue retention. For up to 5 years after a final treatment with a 10 Mg axle load on wet soil, soil shear strength at 70-100 mm and cone index at 180-360 mm were significantly ( P<0.05) higher than in a control treatment, and soil water storage and grain yield were lower. We conclude that compaction effects persisted because (1) there were insufficient wet-dry cycles to swell and shrink the entire compacted layer, (2) soil loosening by tillage was absent and (3) there were fewer earthworms in the compacted soil. Compaction of dry soil with 6 Mg had little effect at any time, indicating that by using wheel traffic only when the soil is dry, problems can be avoided. Unfortunately such a restriction is not always possible because sowing, tillage and harvest operations often need to be done when the soil is wet. A more generally applicable solution, which also ensures timely operations, is the permanent separation of wheel zones and crop zones in the field-the practice known as controlled traffic farming. Where a compacted layer already exists, even on a clay soil, management options to hasten repair should be considered, e.g. tillage, deep ripping, sowing a ley pasture or sowing crop species more effective at repairing compacted soil.
  • Authors:
    • Sau, F.
    • Pineiro, J.
  • Source: Fourrages
  • Issue: 190
  • Year: 2007
  • Summary: The natural conditions in Galice and northern Spain are favourable for the production of forage, compared to the rest of the country. Agriculture in the country has undergone deep restructurations for the last 50 years, especially on the dairy farms. From 1960s onwards, the acreages of grass-clover leys and of forage maize have been constantly increasing, in parallel with an increasing milk production. The proportion of milk produced from forage crops have remained at 20 to 25%, and a particular effort should be made to reach the goal of 40%. In order to overcome water shortage during summer, the farmers make silage with their spring cuts, use lucerne and purchased feeds, and irrigate at a small scale. The few trials made show that irrigated pastures can increase the average yearly production by 40-45%. Since the water resources are scarce, and must be distributed with other economic activities, there should be no large development of irrigation. To overcome the water shortage during summer, it would seem more realistic to have recourse to more intensive rotations (2 crops per year), in which a crop better adapted to high temperatures and to dry spells would take over the leys. This intensified dry-land system would increase the yearly production by from 50 to 82%.
  • Authors:
    • Schmidt, C. J. J.
    • Adriaanse, F. G.
    • Preez, C. C. du
  • Source: South African Journal of Plant and Soil
  • Volume: 24
  • Issue: 1
  • Year: 2007
  • Summary: The principle objective of this study was to establish P fertilizer guidelines for dryland maize on the South African Highveld according to the sufficiency concept of soil extractable P. Data sets from nine different P fertilizer trials at various localities in the Free State, Gauteng, Mpumalanga and North West provinces were used. Different P treatments were applied for all trials in order to establish differences in extractable soil P levels, which were expected to have corresponding effects on maize yield. Long-term rainfall varied from 765 mm per annum for the Dirkiesdorp trial in the east to 494 mm per annum for the Wolmaransstad trial in the west. The duration of trials varied between one and nine seasons. The clay content of the top 150 mm soil at these localities ranged between 8.4 and 47%. Extractable P threshold values with varying R 2 values were derived for all localities. These values were related to soil properties and it was shown that the degree of leaching and silt-plus-clay content were the parameters that explained most of the variation. However, it was decided only to explore relationships between threshold P values and silt-plus-clay contents in more detail. By excluding data from two localities of which the topsoil contained free lime, the R 2 values of the mentioned relationships improved substantially so that P threshold values could be derived from the silt-plus-clay content range of the other seven localities. The extractable soil P threshold concentrations based on Bray 1 for the top 150 mm soil layer, to obtain 90% relative yield varied from 33.5 mg kg -1 at 13% silt-plus-clay to 14.6 mg kg -1 at 60% silt-plus-clay. These P thresholds were much higher on the sandy soils than the value of 19 mg P kg -1 (Bray 1) for 95% relative yield according to the ARC-Grain Crops Institute (1994) guidelines over all soils. This may not necessarily imply that overall more P fertilizers should be applied, since the corresponding soil sampling procedure also measures residual P from enriched zones over rows where P fertilizer was band-placed. Research results used to establish the ARC-Grain Crops Institute (1994) guidelines excluded sampling from enriched zones over rows.
  • 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:
    • Shah, Z.
    • Stromberger, M.
    • Westfall, D.
  • Source: Applied Soil Ecology
  • Volume: 35
  • Issue: 1
  • Year: 2007
  • Summary: In degraded agricultural soils, organic C levels can be increased and conserved by adopting alternative management strategies such as no-tillage and increased cropping intensity. However, soil microbial community responses to increased soil organic C (SOC) may be constrained due to water limitations in semi-arid dryland agroecosystems. The purpose of this study was to assess SOC, microbial biomass C (MBC) and community ester-linked fatty acid methyl ester (EL-FAME) composition under winter wheat ( Triticum aestivum L.) in no-till systems of wheat-corn ( Zea mays L.)-fallow (WCF), wheat-wheat-corn-millet ( Panicum miliaceum L.) (WWCM), wheat-corn-millet (WCM), opportunity cropping (OPP), and perennial grass across a potential evapotranspiration gradient in eastern Colorado. Rotations of WWCM and OPP, in which crops are chosen based on available soil water at the time of planting rather than according to a predetermined rotation schedule, increased levels of SOC to those measured under perennial grass. However, MBC under OPP cropping accounted for the smallest fraction (2.0-3.6%) of SOC compared to other systems, in which MBC ranged from 2.4 to 6.3% of SOC. Microbial community structure was most divergent between OPP-cropped and perennial grass soils, whereas few differences were observed among microbial communities of the WCF, WCM, and WWCM rotations. Compared to perennial grass and other cropping systems, microbial biomass in OPP-cropped soil was low and contained less of the arbuscular mycorrhizal fungal biomarker 16:1omega5 c. Microbial stress, as indicated by the ratio of 17:0 cy to 16:1omega7 c, was greatest under OPP and WCF cropping. In contrast, soils under perennial grass contained lower ratios of bacterial:fungal EL-FAMEs and higher levels of MBC, ratios of MBC:SOC, and relative abundances of 16:1omega5 c. Across locations, SOC and moisture content increased as soil texture became finer, whereas trends in MBC and community structure followed the potential evapotranspiration gradient. Soil from the high potential evapotranspiration site contained the lowest level of MBC but greater relative amounts of 16:1omega5 c and lower ratios of stress indicator and bacterial:fungal EL-FAMEs compared to soil located at the moderate and low potential evapotranspiration sites. Indistinct microbial communities under WCF, WCM, and WWCM could be explained by EL-FAME limitations to detecting slight differences in microbial community structure or to the overwhelming response of microbial communities to environmental rather than management conditions. Further research is needed to assess potential legacy effects of long-term agricultural management that may mask microbial responses to recent management change, as well as to identify conditions that lead to high microbial community resiliency in response to management so that communities are similar under a given crop despite different preceding crops.
  • Authors:
    • Babu, C.
    • Sureshkumar, P.
    • Sivakumar, S.
    • Chandaragiri, K.
    • Thirukumaran, K.
    • Ramesh, S.
    • Umashankar, R.
  • Source: Journal of Ecobiology
  • Volume: 19
  • Issue: 1
  • Year: 2007
  • Summary: Field experiments were carried out at the Tamil Nadu Agricultural University farm, Coimbatore, India, during north-east monsoon seasons of 2000-01 and 2001-02 to design a viable farming system by linking the crop and animal components viz., goat, rabbit and pigeon to sustain crop productivity and profitability and increasing the employment opportunity of dry land farmers. Among the different crops in the farming systems, pearl millet (cumbu) + soyabean grain, maize + cowpea fodder and Cenchrus ciliaris + Stylosanthes scabra fodder system with goat, rabbit and pigeon system were higher economic parameters in the second year than the first year. The economics of the integrated farming system revealed the superiority of pearl millet + soyabean grain, maize + cowpea fodder and C. ciliaris + S. scabra fodder with goat, rabbit and pigeon system in terms of higher total returns of Rs. 162 616 and 206 942, net returns of Rs. 80 924 and 125 250, benefit-cost ratio of 1.99 and 2.53 for every rupee invested and the per day returns (Rs.222 and 343) compared to other systems in first and second year, respectively. It also generated maximum employment opportunity of 490 man-days per year compared to other systems.