• Authors:
    • Li, L.
    • Du, F.
    • Zhang, F.
    • Zhang, W.
    • Li, H.
  • Source: Plant Nutrition and Fertilizer Science
  • Volume: 16
  • Issue: 5
  • Year: 2010
  • Summary: Since 2004, China has significantly increased its grain production due to the impetus of strong policy support from the government, including soil testing and fertilizer recommendation. This paper analyzes the changes in fertilizer efficiency in China's grain production systems by comparing the farmers' practice in 2008 and 2001. In the period investigated, chemical fertilizer application rate increased by 5.4% and 29.0% in wheat and maize production, respectively, and decreased by 4.3% in rice cultivation. Total fertilizer consumption increased by 1.3 * 10 6 t on grain crops, but its proportion decreased from 68% to 50% in the total chemical fertilizer consumption of the country. PFP (partial factor productivity, i.e. grain yield divided by the amount fertilizer), used to represent the fertilizer use efficiency of rice, was higher than that of wheat and maize. The PFP of wheat and rice increased from 10.6 kg/kg to 11.9 kg/kg and from 13.9 kg/kg to 15.7 kg/kg, respectively, and that of maize decreased from 13.8 kg/kg to 11.5 kg/kg. The change of planting structure had a strong impact on fertilizer application. The concentration of the production of main cereal crops to the areas with advantageous conditions is believed to be good to the improvement of fertilizer efficiency of cereal crops. On the other hand,the continuous increase in the cultivation area of economic crops will bring additional variables to the changing trend of fertilizer efficiency in China.
  • Authors:
    • Silva, M.
    • Goncalves, M.
    • Souza, C.
    • Souza, L.
    • Marchetti, M.
    • Mercante, F.
    • Lourente, E.
  • Source: SEMINA-CIENCIAS AGRARIAS
  • Volume: 31
  • Issue: 4
  • Year: 2010
  • Summary: Soil management practices exert important influence on biological and biochemical properties of soil. This work aimed to valuate the impact of crop rotation on soil biochemical and microbiological attributes, as well and influence on corn crop yield. The experiment was carried out during 2005/06 crop season, in Dourados - MS, Brazil. Experimental design was randomized blocks with treatments established in sub-divided plots with tree replications, which seasons were plots and management systems were sub-plots. Studied seasons were winter and summer and no tillage systems were represented by five crop rotation schemes, which involved the cultures of hairy vetch, bean, oat, forage turnip, soybean, crotalaria, corn, sorghum, pearl millet, sunflower and, in conventional tillage, with corn in winter and with soybean in summer. Native vegetation constituted one treatment and, with conventional tillage, it was used as ecosystem of reference as control for comparison between possible alterations in chemical and microbiological attributes with the establishment of a system more conservationist for soil management. There was a positive correlation among Norg, Corg, Porg and C-BMS contents with chemical attributes of soil fertility, which shows interdependence between chemical and biology of soil. The elimination of native vegetation and the substitution for cultivation system after that reduce the C-BMS. In Cerrado conditions, studied cultivation systems increased phosphorus content in soil. Crop rotation influenced corn yield after the cultivation of determined species as crotalaria and vetch in crop rotation.
  • Authors:
    • Manorama, K.
    • Lal, S.
  • Source: Indian Journal of Agronomy
  • Volume: 55
  • Issue: 3
  • Year: 2010
  • Summary: Field trials were conducted on sandy clay loam soils of the Nilgiris during summer seasons of 2003 to 2005 to study the intercropping possibilities of French beans ( Phaseolus vulgaris L), maize ( Zea mays L.) and wheat ( Triticum aestivum L) with potato ( Solanum tuberosum L.) in three population proportions (75:25, 75:50 and 50:50) under rainfed conditions. The results indicated that potato+French bean at 75:50 population recorded significantly higher potato equivalent yield, (PEY) (27.1 t/ha), land equivalent ratio (LER) (1.28) and net returns (Rs 69,090) over sole potato. Intercropping of potato with wheat and maize resulted in significant decrease in PEY over sole potato. Potato is more competitive than other crops as evident from Relative Crowding Coefficient (RCC) values. However, at 50:50 ratios, French bean and maize are more competitive. Potato+maize (75:50 and 50:50) was found soil exhaustive while potato+French bean is soil restorative system.
  • Authors:
    • Gamzatov, I.
    • Muslimov, M.
  • Source: Kormoproizvodstvo
  • Issue: 12
  • Year: 2010
  • Summary: Continuous green fodder conveyor production system allows quality fodder supply during the grazing season. Field trials were conducted in Dagestan, the North Caucasus, Russia, with Red Steppe cattle. Data are tabulated on sowing dates and period of use of fodder crops, i.e. natural pastures, winter rape, winter rye + winter vetch, pea-oat + vetch-oat, regrowth of perennial grasses after hay cutting, Sudan grass, maize and maize + Sudan grass, sorghum, regrowth of Sudan grass and sorghum, maize sown after winter cereals grown for green fodder, maize and sorghum grown for silage for additional feed rations, winter rye after pea + oat, squash, pumpkin, fodder watermelon and fodder beet, and regrowth of natural pastures and meadows. The importance of natural pastures and drought resistant plants, such as sorghum crops, for production of high yield of fodder in dry conditions of Dagestan is considered.
  • Authors:
    • Ossom, E.
  • Source: International Journal of Agriculture and Biology
  • Volume: 12
  • Issue: 4
  • Year: 2010
  • Summary: Sweet potato is a major root storage crop in Swaziland, whereas maize ( Zea mays L.) is the staple food crop in Swaziland. In this experiment, sweet potato cv. Kenya was grown in the field and intercropped with maize cv. SC 603 with the objective of determining the effects of crop association on soil temperature, weed infestation and crop yields. Five plant population treatments (T) were investigated: T 1, Maize alone at 40,000 plants/ha; T 2, sweetpotato alone at 33,333 plants/ha; T 3, maize at 40,000 plants/ha, intercropped with sweetpotato at 33,333 plants/ha; T 4, maize at 40,000 plants/ha, intercropped with sweet potato at 16,666 plants/ha and T 5, sweet potato alone at 16,666 plants/ha. Soil surface temperatures were generally higher than temperatures at 10 cm depth; nonetheless there were no significant differences in soil temperatures among the cropping systems. The three most dominant weed species in all plots were Bidens pilosa L. (37.5-59.3% relative abundance), followed by Cynodon dactylon L. (15.7-43.6%) and Oxalis latifolia (7.1-18.7%). Sida rhombifolia (0-0.4%); Schkuhria pinnata (0-0.4%) and Leucas martinicensis (0-0.4%) were the three least abundant weed species. Land equivalent ratio (LER) values indicated that Sweet potato-maize mixture at the recommended sole sweet potato population (33,333 plants per hectare) was a better cropping system (LER, 0.77) than intercropping at 50% of the recommended Sweet potato (LER, 0.74). Correlation data showed that maize cob yield was not significantly correlated to the 100-grain mass (r=0.508; R 2=0.2581; N, 12); the resultant correlation of determination showed that 25.8% in the variation in cob yield could be ascribed to 100-grain mass. In sweet potato, correlation data showed that the number of tubers per plant was positively correlated to tuber yield ha -1 (r=0.676; R 2=0.4570; N, 16); from the co-efficient of determination, 45.7% of tuber yield could be associated with the number of tubers per plant. In conclusion, sweet potato monocropping was the best system; nonetheless, if it has to be intercropped with maize, there should be 33,333 and 40,000 plants ha -1 of sweet potato and maize, respectively.
  • Authors:
    • Rosolem, C.
    • Olibone, A.
    • Olibone, D.
    • Prando, M.
  • Source: REVISTA BRASILEIRA DE CIENCIA DO SOLO
  • Volume: 34
  • Issue: 3
  • Year: 2010
  • Summary: In soils with physical and/or physical hydric restrictions for root growth, it may be a viable strategy to increase crop productivity by increasing water storage potential through improvements in water infiltration. Accordingly, the objective of this study was to determine water infiltration in a Hapludult in three crop rotations under no-tillage, with and without initial chiseling. Crop rotations consisted of: millet/soybean/sorghum/maize/sorghum; millet/soybean/Brachiaria ruziziensis/corn/Brachiaria ruziziensis; and millet/soybean/Brachiaria ruziziensis+castor bean/corn/Brachiaria ruziziensis+castor bean. Water infiltration in soil was evaluated in the field, using concentric discs at the soil surface and at depths of 0.10 and 0.20 m, in 2006 and 2007. After the first year, chiseling led to increased infiltration of water into the soil. Water infiltration was greatest in the crop rotation system with Brachiaria ruziziensis+castor bean. The activity of root systems of crops in the plots without chiseling increased the rate of water infiltration into the soil.
  • Authors:
    • Sundermeier, A.
    • Diedrick, K. A.
    • Dygert, C. E.
    • Mullen, R. W.
    • Henry, D. C.
  • Source: Agronomy Journal
  • Volume: 102
  • Issue: 1
  • Year: 2010
  • Summary: Inclusion of a winter legume cover crop into a crop rotation has been suggested as a method to provide a substantial portion of the N requirement of the following crop. While the benefits of winter cover crops such as reduced soil erosion, increased soil organic matter, and increased mulch cover have been well documented, the N contribution to the subsequent crop has shown to be variable. The objective of this study was to determine the N contribution from a red clover (Trifolium pratense L.) cover crop following wheat (Triticum aestivum L.) to a subsequent corn (Zea mays L.) crop. The experiment was conducted at two western Ohio locations over 3 yr. At both locations, red clover was either interseeded into wheat or seeded after harvest, the red clover cover crop was eliminated with tillage or herbicide application, and corn was planted with three N rates (0, 90, and 180 kg N ha(-1)). The data revealed that for three of the four site years (when the cover crop was successfully established) there was no N contribution attributable to the presence of red clover. The one site that did show a N contribution revealed that the amount of N contributed was less than 90 kg N ha(-1). However, even when no N benefit was found, yields were improved by non-N-related rotational effects. Significant reductions in N fertilization rates following a red clover cover crop are likely to result in lost corn yield opportunities in western Ohio.
  • Authors:
    • Jajoo, S. B.
    • Kambale, P. G.
    • Atal, G. R.
  • Source: Green Farming OR Soil & Water Conservation Engineering
  • Volume: 1
  • Issue: 1
  • Year: 2010
  • Summary: A study was conducted to suggest optimal resources allocation i.e. land and water using linear programming model for Amravati district in Maharashtra State. Considering the land capability classification, availability of water in different seasons, crop water requirements, food requirements of the district, affinity towards the crops and investment capacity of peoples, crop plan was developed to maximize the net return. In existing crop plan during kharif season major area is under cotton (32.41%) followed by soybean (20.19%) whereas in proposed optimal crop plan without capital constraints major area was allocated under soybean (30%), cotton (10%) and jowar (10%) of cultivable area. In rabi major area in existing crop plan is under gram (5.2%) whereas in proposed plan area is allocated to wheat (30%) followed by gram (27%). In existing crop plan gross investment and net return were Rs. 9,268 and Rs. 4,906 per ha where as in proposed plan Rs. 16,057 and Rs. 9,642 per ha. Thus increases net return by Rs. 4,362 by increasing gross investment of Rs. 6,415 per ha.
  • Authors:
    • Maeder, P.
    • Niggli, U.
    • Wiemken, A.
    • Burger, D.
    • Berner, A.
    • Krauss, M.
  • Source: Soil Use and Management
  • Volume: 26
  • Issue: 1
  • Year: 2010
  • Summary: To promote conservation tillage in organic farming systems, weed control and ley removal within arable-ley rotations need to be optimized. A long-term field trial was thus established in Frick, Switzerland in 2002 on a clayey soil and with a mean precipitation of 1000 mm/year. The tillage experiment distinguished between conventional tillage with mouldboard ploughing (CT, 15 cm depth) and reduced tillage (RT), including a chisel plough (15 cm) and a stubble cleaner (5 cm). Results of a 2-year grass-clover ley (2006/2007) and silage maize (2008) are presented. Due to dry conditions, mean grass-clover yields were 25% higher in RT than in CT, indicating better water retention of RT soils. Clover cover and mineral contents of the fodder mixture were also higher in RT. The ley was successfully removed in autumn 2007 in RT plots, and a winter pea catch crop was sown before maize. In CT, ploughing took place in spring 2008. Maize yields were 34% higher in RT than in CT, despite a two- to three-fold higher but still tolerable weed infestation. Maize in RT plots benefited from an additional 61.5 kg of easily decomposable organic N/ha incorporated into the soil via the pea mulch. Measurement of arbuscular mycorrhizal colonization of maize roots indicated a similar mechanical disturbance of the topsoil through the reduced ley removal system compared with ploughing. It is suggested that RT is applicable in organic farming, even in arable-ley rotations, but long-term effects need further assessment.
  • Authors:
    • Lal, R.
  • Source: Crop Science
  • Volume: 50
  • Issue: Supplement 1
  • Year: 2010
  • Summary: Global cereal production must be increased by ~50% by 2050. Crop yields in sub-Saharan Africa and South Asia have either stagnated or declined since the 1990s because of the widespread use of extractive farming practices and problems of soil and environmental degradation. Yield potential of improved varieties and elite germplasm is not realized because of soil degradation. The concept of eco-efficiency implies efficient and sustainable use of resources in agronomic production and soil management. However, it is not enough to merely minimize the environmental impact. It is also important to maximize agronomic production while enhancing ecosystem services. Most degraded and depleted soils of agro-ecosystems contain a lower soil organic carbon (SOC) pool than in those under natural ecosystems. Thus, restoring the SOC pool is essential to improving soil quality, increasing eco-efficiency, and enhancing numerous ecosystem services. Increasing the SOC pool in the root zone can enhance agronomic production (kg grains ha -1 Mg C -1) at the rate of 200 to 300 for maize ( Zea mays L.), 30 to 60 for bean ( Phaseolis vulgaris L.), 20 to 40 for wheat ( Triticum aestivum L.), 20 to 50 for soybean [ Glycine max (L.) Merr.], and 20 to 50 for rice ( Oryza sativa L.). Not all improved management practices are applicable to all soil and ecological conditions. However, no-till farming along with application of crop residue mulch, manuring, legume-based complex rotations, and integrated nutrient management should be applicable under most conditions. Global food insecurity, affecting 1.02 billion people in 2009, can only be alleviated by improving soil quality and eco-efficiency through restoration of degraded/depleted soils.