• Authors:
    • Yaduraju, N. T.
    • Das, T. K.
    • Tadesse, B.
  • Source: Weed Biology and Management
  • Volume: 10
  • Issue: 3
  • Year: 2010
  • Summary: Parthenium is widely distributed across the uncropped areas of the tropics. It has slowly encroached into many crops and causes considerable yield loss. It heavily infests sorghum, which is widely cultivated by the resource-poor farmers in Africa and Asia. Its interference and management in sorghum in these cropping systems is not well understood. Therefore, this experiment was undertaken to determine the appropriate parthenium management techniques to use in sorghum crops. All the studied weeds, in combination with parthenium, offered greater competition to sorghum than parthenium alone. Similarly, under a composite stand of weeds, parthenium was inferior in competitiveness to the other weeds until 60 days after sowing (DAS); by 90 DAS, it could accumulate a higher dry weight due to its consistent growth. A pre-emergence treatment of atrazine (0.75 kg ha -1) with wheat straw mulch (5.0 t ha -1) brought about a consistent and significant reduction in the parthenium growth and, consequently, increased the sorghum yield by 90.8%. Cowpea intercropping with and without pendimethalin (1.0 kg ha -1) as a pre-emergence treatment could not control parthenium between 0 and 60 DAS, but could reduce the parthenium growth during the later period of 60-90 DAS, which resulted in a significant increase in sorghum growth. These intercropping treatments increased the sorghum grain yield by 156.2% and 142.4%, respectively, over the unweeded control and by 18.5% and 12.1%, respectively, over the weed-free control. These treatments also promoted a higher uptake of N, P, and K by the sorghum crop. Thus, cowpea intercropping was the most effective method for parthenium management vis-a-vis sorghum yield improvement, followed by cowpea intercropping with pendimethalin and then by atrazine as a pre-emergence treatment with wheat straw mulch.
  • Authors:
    • Khan, A.
    • Khan, Q.
    • Saif-ur-Rehman
    • Sanaullah
  • Source: Journal of Agricultural Research (Lahore)
  • Volume: 48
  • Issue: 2
  • Year: 2010
  • Summary: In a field experiment conducted at Agricultural Research Institute, Dera Ismail Khan, Pakistan during 2004-06 effect of bio-chemical amendments {FYM, gypsum, press mud and dhaincha (green manure)} on phosphate availability and wheat yield was studied under rice-wheat cropping pattern in salt affected soil. The result showed that all treatments significantly (P
  • Authors:
    • Muchaonyerwa, P.
    • Chiduza, C.
    • Murungu, F. S.
  • Source: African Journal of Agricultural Research
  • Volume: 5
  • Issue: 13
  • Year: 2010
  • Summary: Production of large biomass yields and weed suppression from cover crops have been major constraints affecting success and uptake of conservation agriculture technologies by smallholder irrigation farmers. A field study was undertaken to evaluate biomass accumulation and N uptake by oats ( Avena sativa), grazing vetch ( Vicia dasycarpa), faba bean ( Vicia faba), forage peas ( Pisum sativum) and Lupin ( Lupinus angustifolius) and their winter weed suppression efficacy in the 2007 and 2008 winter seasons. Cover crops were grown at two fertiliser levels: no fertiliser and fertilized. Control plots were included where no cover crop was grown. At the end of each winter season, glyphosate was applied to kill the cover crops and maize planted. Oats, grazing vetch and forage pea's cover crops produced mean dry weights of 13873, 8945.5 and 11073 kg ha -1 respectively while lupin had the lowest dry weight of 1226 kg ha -1. Oats responded to fertilisation while, there was little or no response from the other cover crops. Oats and grazing vetch also reduced weed density by 90 and 80% respectively while lupin only reduced weed density by 23% compared with the control plots. Grazing vetch fixed a mean of 112 kg N ha -1. The results suggest that legumes such as grazing vetch and forage peas may be grown to maximise biomass yields with minimal fertilizer inputs. Amount of biomass produced was a major factor in controlling winter weeds, while there was a progressive decline in the winter weed burden from the first to the second season. The low C:N ratio of grazing vetch (
  • Authors:
    • Wu, Z.
    • Yu, T.
    • Song, F.
    • Zhuoremu, T.
    • Shi, Y.
    • Hadier, Y.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 47
  • Issue: 5
  • Year: 2010
  • Summary: Objective: The microclimatic factors in different jujube-wheat intercropping densities (3 m * 4 m, 2 m * 6 m) and jujube-cotton intercropping densities (3 m * 4 m, 2 m * 6 m) were studied in the arid area of the Tarim basin, in order to improve theory of Jujube-crops intercropping, optimize intercropping model, and provide theoretic basis for crop selection. Method: Auto-meteorology Vantage Pro2 and portable meteorological instrument KS4000 were used to observe the microclimatic factors, such as light intensity, air temperature and humidity, wind speed and direction. The ground temperature was tested by WQG-15 thermomicro-climatemeter at same time. Result: The climatic factors changed to some extent with different jujube-crops intercropping systems. Within the same intercropping system, the micro-climate varied in different lines, especially for light intensity. Among the different intercropping system, the order of light intensity was 3*4 (m) jujube-wheat intercropping
  • Authors:
    • Al-Naeem, M.
  • Source: American Journal of Plant Physiology
  • Volume: 5
  • Issue: 3
  • Year: 2010
  • Summary: A field study was carried out to determine the effect of irrigation scheduling on growth parameters and Water Use Efficiency (WUE) of barley and faba bean crops for optimum production during the winter seasons of 2001-02 and 2002-03. Four irrigation treatments T 1 (application of water at field capacity soil moisture), T 2, T 3 and T 4 irrigation at 15, 30 and 45% soil moisture depletion of the available water at field capacity of soil, respectively were tested on a loamy-sand soil. Plant growth parameters of both the crops were significantly affected by the different irrigation treatments. Mean barley grain yield ranged from 4.52-6.72 Mg ha -1 and the faba bean seed yield from 0.86-1.45 Mg ha -1 in different irrigation treatments. The WUE, based on total grain/seed yield ranged between 0.90-148 kg m -3 of water for barley and 0.17-0.30 kg m -3 of water for faba bean in different irrigation treatments. There was no significant difference in WUE of barley and faba bean crops between T 1 and T 2 treatments. The WUE was slightly higher in T 2 (irrigation at 15% soil moisture depletion) than T 1 (irrigation at soil moisture of field capacity level). In conclusion, appreciable grain yield of barley and faba bean seed can be achieved if irrigated at 15% soil moisture depletion. The study provided useful information for scheduling irrigation of barley and faba bean crops under arid environment for efficient water use and management.
  • Authors:
    • Muller, C.
    • Amor, T.
  • Source: Agricultural Journal
  • Volume: 5
  • Issue: 2
  • Year: 2010
  • Summary: In this study, we estimate agricultural technology for Tunisian peasants, accounting for the crop choice of perasants and distinguishing inputs for individual crops such as: vegetable farming cereal and fruit-trees. The study employed the use of cross-section data from distinguishable irrigated crops survey conducted on a sample of 218 farmers frome 11 regions in Tunisia. The data were collected with the aid of structured questionnaire and were later analysed. The Cobb Douglass production frontier model is employed in order to analyse data collected. Among the irrigated crop farmers, the significant variables were: farmuar manuar fertiliser quantity, labor, mecanic traction and among of irrigated water applied. The estimated sigma square (sigma 2) and gamma (gamma) are widely significants for all irrigated crops and revealed that >85% of the variation in the Tunisian irrigated output among farmers in the study area are due to the differences in their efficiencies. Howerver, we find that predicted technical efficiency widely varies across farms and crops from an average of 54.7% for vegetable farming up to 80.6% for fruit-trees. The study also revealed the existing on inefficiency effects among the farmers as: education, farmer's age, irrigation techniques, lack of education, property of land.
  • Authors:
    • Zhang, J.
    • Zhang, X.
    • Sun, J.
    • Kang, S.
    • Du, T.
  • Source: Agricultural Water Management
  • Volume: 97
  • Issue: 1
  • Year: 2010
  • Summary: Water shortage is the major bottleneck that limits sustainable development of agriculture in north China. Crop physiological water-saving irrigation methods such as temporal (regulated deficit irrigation) and spatial (partial root zone irrigation) deficit irrigation have been tested with much improved crop water use efficiency (WUE) without significant yield reduction. Field experiments were conducted to investigate the effect of (1) spatial deficit irrigation on spring maize in arid Inland River Basin of northwest China during 1997-2000; (2) temporal deficit irrigation on winter wheat in semi-arid Haihe River Basin during 2003-2007 and (3) temporal deficit irrigation on winter wheat and summer maize in Yellow River Basin during 2006-2007. Results showed that alternate furrow irrigation (AFI) maintained similar photosynthetic rate ( Pn) but reduced transpiration rate ( Tr), and thus increased leaf WUE of maize. It also showed that the improved WUE might only be gained for AFI under less water amount per irrigation. The feasible irrigation cycle is 7d in the extremely arid condition in Inner River Basin of northwest China and less water amount with more irrigation frequency is better for both grain yield and WUE in semi-arid Haihe River Basin of north China. Field experiment in Yellow River Basin of north China also suggests that mild water deficit at early seedling stage is beneficial for grain yield and WUE of summer maize, and the deficit timing and severity should be modulated according to the drought tolerance of different crop varieties. The economical evapotranspiration for winter wheat in Haihe River Basin, summer maize in Yellow River Basin of north China and spring maize in Inland River Basin of northwest China are 420.0 mm, 432.5 mm and 450.0 mm respectively. Our study in the three regions in recent decade also showed that AFI should be a useful water-saving irrigation method for wide-spaced cereals in arid region, but mild water deficit in earlier stage might be a practical irrigation strategy for close-planting cereals. Application of such temporal and spatial deficit irrigation in field-grown crops has greater potential in saving water, maintaining economic yield and improving WUE.
  • Authors:
    • Hao, M.
    • Fan, J.
    • Malhi, S.
  • Source: Canadian Journal of Soil Science
  • Volume: 90
  • Issue: 3
  • Year: 2010
  • Summary: Nitrate (NO 3-) leaching and water contamination have become a worldwide concern. In this review, some examples are presented to show the extent and magnitude of NO 3- accumulation in the soil profiles and its potential effects on contamination of ground water and surface water under dryland farming in northern China. Climatic and management factors affecting NO 3- leaching are also discussed. In northern China, rainfall is relatively sparse, but the high intensity of precipitation and porous soils play an important role in the accumulation of NO 3N in soil and its subsequent leaching in the soil profile. There is a risk of nitrate accumulation and leaching when high rates of fertilizer N are applied to improve crop yields, and it becomes even worse when conventional land use is changed from cereal crops to vegetable crops and fruit orchards. Under such conditions, shallow ground water might be polluted by NO 3-. This suggests that more attention should be paid to prevent this problem by using best management practices, especially by controlling the amount of N fertilizer input, balanced fertilization, split N application, inclusion of crops with deep taproots in the rotation and minimizing summer fallow (especially tilled) frequency.
  • Authors:
    • Abbaspour, K.
    • Schulin, R.
    • Yang, H.
    • Faramarzi, M.
  • Source: Agricultural Water Management
  • Volume: 97
  • Issue: 11
  • Year: 2010
  • Summary: In most parts of Iran, water scarcity has been intensifying and posing a threat to the sustainability of agricultural production. Wheat is the dominant crop and the largest irrigation water user in Iran; hence, understanding of the crop yield-water relations in wheat across the country is essential for a sustainable production. Based on a previously calibrated hydrologic model, we modeled irrigated and rainfed wheat yield ( Y) and consumptive water use ( ET) with uncertainty analysis at a subbasin level in Iran. Simulated Y and ET were used to calculate crop water productivity ( CWP). The model was then used to analyze the impact of several stated policies to improve the agricultural system in Iran. These included: increasing the quantity of cereal production through more efficient use of land and water resources, improving activities related to soil moisture conservation and retention, and optimizing fertilizer application. Our analysis of the ratio of water use to internal renewable water resources revealed that 23 out of 30 provinces were using more than 40% of their water resources for agriculture. Twelve provinces reached a ratio of 100% and even greater, indicating severe water scarcity and groundwater resource depletion. An analysis of Y-CWP relationship showed that one unit increase in rainfed wheat yield resulted in a lesser additional water requirement than irrigated wheat, leading to a larger improvement in CWP. The inference is that a better water management in rainfed wheat, where yield is currently small, will lead to a larger marginal return in the consumed water. An assessment of improvement in soil available water capacity ( AWC) showed that 18 out of 30 provinces are more certain to save water while increasing AWC through proper soil management practices. As wheat self-sufficiency is a desired national objective, we estimated the water requirement of the year 2020 (keeping all factors except population constant) to fulfill the wheat demand. The results showed that 88% of the additional wheat production would need to be produced in the water scarce provinces. Therefore, a strategic planning in the national agricultural production and food trade to ensure sustainable water use is needed. This study lays the basis for a systematic analysis of the potentials for improving regional and national water use efficiency. The methodology used in this research, could be applied to other water scarce countries for policy impact analysis and the adoption of a sustainable agricultural strategy.
  • Authors:
    • Rasul, G.
  • Source: International Journal of Rural Management
  • Volume: 6
  • Issue: 1
  • Year: 2010
  • Summary: Although South Asian countries made impressive progress in food production during 1960s, 1970s and 1980s, the dynamism in the agricultural sector has, however, lost recently. Productivity of major food grains has slowed down and even declined, for some crops and food production is failing to keep pace with population growth. Therefore, food security has remained a major concern in South Asian countries. The linkage between food production and the Himalayan mountains is poorly understood though the Himalayan mountains are the major source of dry season water in Pakistan, Nepal, Bangladesh and Bhutan for irrigated rice and wheat, which are the staple food in South Asia. In view of that this article briefly examines the role of the Himalayan mountain systems in food production and agricultural sustainability in South Asian countries looking at the emerging challenges posed by the increasing water stress and climate change. The analysis suggests that a common challenge is being faced by all South Asian countries - for increased food production to meet the demand of burgeoning population, the growing stress of water as rice and wheat, the staple food in South Asia, require huge amounts of water. Moreover, the increased food production in South Asia has to come from the same amount of land, by increasing productivity through bringing additional land under irrigation, as the frontier for expansion of agricultural land has almost been exhausted. The availability of irrigation water is, therefore, critical for increased food production and agricultural sustainability in entire South Asia. Climate change introduces a new challenge to agriculture and food security in South Asia. Recent studies suggest that the impact of climate change on cereal production in South Asia could be negative and that may be as high as 18.2-22.1 per cent. Our analysis reveals that the Hindu Kush-Himalayan mountain systems play a significant role in agriculture and food security in South Asia through water supply, climate and wind regulation, groundwater recharge and in sustaining wetland ecosystems. It is the major source of dry season water for several large river systems, such as the Indus, the Ganges and the Brahmaputra from the snow and glacier melt of the Himalayas, which provide the main basis for surface and groundwater irrigation. These three rivers form the largest river basins (Indo-Ganga-Brahmaputra) which are the major source of rice and wheat in South Asia. Besides surface water, the contribution of mountain discharge to groundwater is also significant, which makes it an important resource for agriculture and food security in South Asia. In addition to providing surface and groundwater, the Himalayan mountain system provides huge inputs to agriculture through regulating micro-climates as well as wind and monsoon circulation, and by supporting river and wetland ecosystems in South Asia. It is estimated that the Ganges river ecosystem alone supports 25,000 or more species, ranging from micro-organisms to mammals, which support agricultural sustainability and provide livelihoods for millions of people. This article concludes that the long-term agricultural sustainability and food security of South Asia is heavily dependent on the water and other ecosystem services it receives from the Himalayan ecosystems. Attention therefore must be paid to conserve the Himalayan ecosystems in order to ensure sustained flow of ecosystem services required for agriculture, food production and overall well-being of Himalayan and downstream population. Options and opportunities for enhancing the agricultural sustainability and food security by sustainable utilization of Himalayan resources and ecosystem services are briefly analyzed and suggestions have been made.