• Authors:
    • Tiwari, K. N.
    • Kaore, S. V.
  • Source: Fertiliser Marketing News
  • Volume: 42
  • Issue: 8
  • Year: 2011
  • Summary: Earlier, it was believed that continued and even increased use of fertilisers is essential for sustaining India's high yielding agriculture. Of late, it has been experienced that by increasing the doses of NPK through fertilisers, crop productivity cannot be sustained mainly due to decline in organic carbon content and depletion of soils nutrient reserves leading to multiple nutrients deficiencies, imbalanced use of nutrients and many more factors depending on location specific areas. This, indeed, is a major challenge to those who are concerned with agricultural development and fertiliser use in the country. The escalating prices of fertilisers and raw materials required for production of fertilisers in global market have made it necessary to search the alternatives sources giving due emphasis to renewable nutrient sources to ensure sustainable agricultural development in the country. Experience shows that the goal of sustainable agriculture can be achieved by technological manipulations blending the indigenous knowledge with modern technologies suited to specific agro-ecological regions. Integrated use of all the nutrient resources (fertilisers, organics, crop residues, biofertilisers, industrial wastes/byproducts etc.) would be essential and inevitable. At least 25% of the total nutrient needs of India can be managed with organic manures, crop residues, biofertilisers and industrial wastes. Apart from this, our focus should be on efficient land and water management coupled with responsible plant nutrient supply along with best management practices. Various components of land and water management suited to site-specific conditions need to be adopted to ensure India's food, nutrition and environmental security. This paper highlights the sustainable pathways towards greening India's "Green Revolution" for sustainable agricultural development. The salient findings of the "Soil Rejuvenation and Productivity Enhancement Project" recently initiated by the IFFCO have also been briefly elucidated in this paper.
  • Authors:
    • Maalouf, F.
    • Lahmer, F. Z.
    • Mastrorilli, M.
    • Katerji, N.
    • Oweis, T.
  • Source: European Journal of Agronomy
  • Volume: 35
  • Issue: 1
  • Year: 2011
  • Summary: The response of faba bean ( Vicia faba L., variety ILB1814) was evaluated in a factorial salinity-drought experiment, combining three levels of salinity in the irrigation water (EC 1.0, 2.3 and 3.6 dS/m) and two levels of plant water status during two successive cropping seasons. The two levels of plant water status were obtained by supplying irrigation when the pre-dawn leaf water potential of the control treatments attained values of -0.3 and -0.6 MPa. The experiment was designed to analyse the effects of soil salinity, the effects of drought (detected by the level of the plant water status), and the combined effect of salinity and drought on the plant-water relationships, nitrogen balance and crop productivity (for both grain and straw). Soil salinity levels equal to or higher than 6.5 dS m -1 affected the plants by reducing the grain number but not the straw weight. Drought at flowering, early podding and grain-filling stages reduced both grain and straw yields. Moreover, yield reductions were associated with increasing soil salinity levels, confirming an interaction between the salinity and drought effects on faba bean productivity. Symbiotic nitrogen fixation, as evaluated by the nitrogen balance, was more affected by drought than by salinity, and it may explain the absence of any observed effects of salinity under drought conditions. The comparison of these results with those obtained in similar experiments on wheat and barley revealed that these cereals and faba bean have contrasting behaviours under saline-drought conditions.
  • Authors:
    • Joshi, A. K.
    • Dixon, J.
    • Waddington, S. R.
    • Li, X.Y.
    • Vicente, M. C. de
  • Source: Food Security
  • Volume: 3
  • Issue: 1
  • Year: 2011
  • Summary: Variation in water availability is a major source of risk for agricultural productivity and food security in South Asia. Three hundred and thirty expert informants were surveyed during 2008-09 to determine the relative importance of drought and water-related constraints compared with other constraints limiting the production of four major food crops (wheat, rice, sorghum, chickpea) in five broad-based South Asian farming systems. Respondents considered drought an important constraint to crop yield in those farming systems that are predominantly rainfed, but associated it with low yield losses (well below 10% of all reported losses) for crops in farming systems with well-developed irrigation. In these systems, other water-related constraints (including difficult access to sufficient irrigation water, the high cost of irrigation, poor water management, waterlogging and flooding of low-lying fields) were more important. While confirming the importance of drought and water constraints for major food crops and farming systems in South Asia, this study also indicated they may contribute to no more than 20-30% of current yield gaps. Other types of constraint, particularly soil infertility and the poor management of fertilizer and weeds for the cereals, and pests and diseases for chickpea, contributed most yield losses in the systems. Respondents proposed a wide range of interventions to address these constraints. Continued investments in crop-based genetic solutions to alleviate drought may be justified for food crops grown in those South Asian farming systems that are predominantly rainfed. However, to provide the substantial production, sustainability and food security benefits that the region will need in coming decades, the study proposed that these be complemented by other water interventions, and by improvements to soil fertility for the cereals and plant protection with chickpea.
  • Authors:
    • Bueckert, R.
    • Gan. Y.T.
    • Liu, L. P.
    • Rees, K. van
  • Source: Field Crops Research
  • Volume: 122
  • Issue: 3
  • Year: 2011
  • Summary: Oilseed and pulse crops have been increasingly used to diversify cereal-based cropping systems in semiarid environments, but little is known about the root characteristics of these broadleaf crops. This study was to characterize the temporal growth patterns of the roots of selected oilseed and pulse crops, and determine the response of root growth patterns to water availability in semiarid environments. Canola ( Brassica napus L.), flax ( Linum usitatissimum L.), mustard ( Brassica juncea L.), chickpea ( Cicer arietinum L.), field pea ( Pisum sativum L.), lentil ( Lens culinaris), and spring wheat ( Triticum aestivum L.) were tested under high- (rainfall+irrigation) and low- (rainfall only) water availability conditions in southwest Saskatchewan, in 2006 and 2007. Crops were hand-planted in lysimeters of 15 cm in diameter and 100 cm in length that were installed in the field prior to seeding. Roots were sampled at the crop stages of seedling, early-flower, late-flower, late-pod, and physiological maturity. On average, root length density, surface area, diameter, and the number of tips at the seedling stage were, respectively, 41, 25, 14, and 110% greater in the drier 2007 than the corresponding values in 2006. Root growth in all crops progressed rapidly from seedling, reached a maximum at late-flower or late-pod stages, and then declined to maturity; this pattern was consistent under both high- and low-water conditions. At the late-flower stage, root growth was most sensitive to water availability, and the magnitude of the response differed between crop species. Increased water availability increased canola root length density by 70%, root surface area by 67%, and root tips by 79% compared with canola grown under low-water conditions. Water availability had a marginal influence on the root growth of flax and mustard, and had no effect on pulse crops. Wheat and two Brassica oilseeds had greater root length density, surface area and root tips throughout the entire growth period than flax and three pulses, while pulse crops had thicker roots with larger diameters than the other species. Sampling roots at the late-flower stage will allow researchers to capture best information on root morphology in oilseed and pulse crops. The different root morphological characteristics of oilseeds, pulses, and wheat may serve as a science basis upon which diversified cropping systems are developed for semiarid environments.
  • Authors:
    • Bueckert, R.
    • Gan, Y. T.
    • Liu, L. P.
    • Rees, K. van
  • Source: Field Crops Research
  • Volume: 122
  • Issue: 3
  • Year: 2011
  • Summary: Root distribution patterns in the soil profile are the important determinant of the ability of a crop to acquire water and nutrients for growth. This study was to determine the root distribution patterns of selected oilseeds and pulses that are widely adapted in semiarid northern Great Plains. We hypothesized that root distribution patterns differed between oilseed, pulse, and cereal crops, and that the magnitude of the difference was influenced by water availability. A field experiment was conducted in 2006 and 2007 near Swift Current (50°15′N, 107°44′W), Saskatchewan, Canada. Three oilseeds [canola ( Brassica napus L.), flax ( Linum usitatissimum L.), mustard ( Brassica juncea L.)], three pulses [chickpea ( Cicer arietinum L.), field pea ( Pisum sativum L.), lentil ( Lens culinaris)], and spring wheat ( Triticum aestivum L.) were hand-planted in lysimeters of 15 cm in diameter and 100 cm in length which were pushed into soil with a hydraulic system. Crops were evaluated under low- (natural rainfall) and high- (rainfall+irrigation) water conditions. Vertical distribution of root systems was determined at the late-flowering stage. A large portion (>90%) of crop roots was mainly distributed in the 0-60 cm soil profile and the largest amount of crop rooting took place in the top 20 cm soil increment. Pulses had larger diameter roots across the entire soil profile than oilseeds and wheat. Canola had 28% greater root length and 110% more root tips in the top 10 cm soil and 101% larger root surface area in the 40 cm soil under high-water than under low-water conditions. In 2007, drier weather stimulated greater root growth for oilseeds in the 20-40 cm soil and for wheat in the 0-20 cm soil, but reduced root growth of pulses in the 0-50 cm soil profile. In semiarid environments, water availability did not affect the vertical distribution patterns of crop roots with a few exceptions. Pulses are excellent "digging" crops with a strong "tillage" function to the soil due to their larger diameter roots, whereas canola is more suitable to the environment with high availability of soil water that promotes canola root development.
  • Authors:
    • Souza, R. F. de
    • Medeiros, M. A. de
    • Marouelli, W. A.
    • Resende, F. V.
  • Source: Horticultura Brasileira
  • Volume: 29
  • Issue: 3
  • Year: 2011
  • Summary: The efficient use of water and the environmental diversity are crucial to the balance and sustainability of the organic production system of tomatoes. The present study aimed to evaluate the organic production of tomato cultivated as a single crop and in consortium with coriander, under sprinkler and drip irrigation. The experiment was carried out at an organic production area on the Federal District of Brazil. The experimental design was randomized blocks with treatments arranged in a 2*2 factorial (two irrigation systems * two cropping schemes). No significant interaction between the both factors occurred, and there was no significant effect of the cropping scheme over the evaluated variables. Although the crop cycle has been reduced when tomato was drip irrigated, the fruit yield was not affected by the irrigation systems. The larger reduction in the stand of plants observed under sprinkler irrigation has been compensated by an increase in the number of fruits per plant, without a change on the fruit mass. The smaller volume of soil explored by the tomato roots associated with the higher incidence of South American tomato pinworm ( Tuta absoluta) and mainly powdery mildew ( Leveillula taurica) may have limited the yield of drip irrigated tomato. The fruit decay rate on sprinkle irrigated plants was twice the rate found on the drip irrigated system.
  • Authors:
    • Knies, A. E.
    • Streck, N. A.
    • Radons, S. Z.
    • Martins, J. D.
    • Carlesso, R.
  • Source: Ciência Rural
  • Volume: 41
  • Issue: 6
  • Year: 2011
  • Summary: The plastochron, which is the time interval between the appearance of two successive nodes and the final node number (FNN) are important variables of the vegetative development in soybean. The objective of this study was to determine the plastochron and the FNN of soybean ( Glycine max (L.) Merrill) cultivars sown in different dates under irrigated conditions in a subtropical location. A field experiment was carried out in Santa Maria, RS, Brazil during 2005/2006 growing season, with three sowing dates (09/11/2005, 09/12/2005 and 28/01/2006). It was used 15 soybean cultivars recommended for the Central and North Argentina, and South and Southeast Brazil. The variables measured were the number of nodes (NN) and the (FNN) on the main stem. The plastochron was estimated by the inverse of the slope of the linear regression between NN and the thermal time (base temperature=10degreesC) accumulated since plant emergence. The late sowing resulted in lower plastochron and FNN, probably because of the lower photoperiod under which the plants were submitted in the node phase, a typical response of short day plants.
  • Authors:
    • Mapurazi, S.
    • Mapfaire, L.
    • Masona, C.
    • Makanda, R.
  • Source: Journal of Sustainable Development
  • Volume: 4
  • Issue: 6
  • Year: 2011
  • Summary: A study was carried out in March 2010 at Firle Sewage Works in Harare, Zimbabwe to determine the effects of long term wastewater irrigation on the concentrations of heavy metals (Zn, Cu, Mn, Cd, Pb, Ni, Fe and Cr) in soil, and their subsequent accumulation in maize plants. The study revealed that long term wastewater use for irrigation results in heavy metal accumulation in soils and bioaccumulation in plants beyond maximum permissible limits (MPL) for both humans and livestock consumption. Lead had highest transfer factor and iron had the least transfer factor. The soil pH was found to be less acidic (pH=5.6) in soils exposed to waste water than in soils where no wastewater had been applied (pH=5). As a recommendation there is need for phytoextraction of heavy metals by intercropping maize plants with local agro forestry shrubs to reduce amount of heavy metals in the soil.
  • Authors:
    • Middleton, A. B.
    • Bremer, E.
    • McKenzie, R. H.
    • Pfiffner, P. G.
    • Woods, S. A.
  • Source: Canadian Journal of Plant Science
  • Volume: 91
  • Issue: 2
  • Year: 2011
  • Summary: High crop productivity is essential for irrigated crops and may be strongly affected by decisions of seeding date and rate. An irrigated field experiment was conducted at two locations in southern Alberta for 4 yr to compare the impact of seeding date and rate on productivity and quality of nine cereal crops and two oilseed crops. Seeding rate was only evaluated on one date in late April or early May, when maximum yields were expected. Delayed seeding reduced crop yields by 0.6 to 1.7% per day after the end of April: flax ( Linum usitatissimum L.) ≤ CWRS wheat ( Triticum aestivum L.), feed triticale (* Triticosecale W.) ≤ CPS or SWS wheat ≤ triticale or barley ( Hordeum vulgare L.) silage ≤ durum ( T. turgidum L.), feed or malt barley
  • Authors:
    • Mengistu, A.
    • Bellaloui, N.
    • Ray, J. D.
    • Smith, J. R.
  • Source: Plant Disease
  • Volume: 95
  • Issue: 9
  • Year: 2011
  • Summary: The seasonal progress of charcoal rot (caused by Macrophomina phaseolina) was measured over two growing seasons in four separate experiments: irrigated infested, irrigated non-infested, non-irrigated infested, and non-irrigated noninfested. Disease was assessed at V5, R1, R3, R5, R6, and R7 growth stages based on colony forming units (CFU) of M. phaseolina recovered from the lower stem and root tissues and the area under the disease progress curve (AUDPC). The population density of M. phaseolina increased slowly from the V5 to R6 growth stages and then rapidly from the R6 to R7 growth stages for all genotypes in all four experiments. Yield loss due to charcoal rot ranged from 6 to 33% in irrigated environments. The extent of yield loss was affected by severity of charcoal rot, which in turn was affected by year. Yield loss due to charcoal rot was consistently measured in all paired comparisons in irrigated environments, suggesting that charcoal rot can be an important disease in irrigated environments. Disease severity based on CFU accounted for more yield loss variation (42%) than did the AUDPC (36%) when used to assess disease. Growth stage R7 was found to be the optimum stage for assessing disease using CFU. In addition, screening soybean genotypes under irrigation environment may have utility in breeding programs where there is a need for evaluating soybean genotypes for both disease resistance and yield.