• Authors:
    • Ma, X. W.
    • Liu, H.
    • Xu, Y. M.
    • Chen, B. Y.
    • Niu, X. X.
    • Wang, B.
    • Yang, T.
    • Zhu, J. R.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 48
  • Issue: 4
  • Year: 2011
  • Summary: Objective: To reveal how water affects fertilizer is important to make decision to regulate and control water and fertilizer use. Method: The paper described temporal-spatial character of soil N extracted by alkaline affected by different irrigation water usage in Awati County, Xinjiang. Result: Irrigation resulted in change of soil N content in depth from 0 cm to 100 cm obviously, especially from 0 cm to 40 cm; generally the more water irrigated, the more nitrogen dissolved and moved down. Conclusion: One reason that water promoted fertilizer use efficiency was to enlarge distribution area of nitrogen in soil profile, then more cotton roots could adsorb nutrients.
  • Authors:
    • Lee, G. J.
    • Abdel-Haleem, H.
    • Boerma, R. H.
  • Source: Theoretical and Applied Genetics
  • Volume: 122
  • Issue: 5
  • Year: 2011
  • Summary: Drought stress adversely affects soybean at various developmental stages, which collectively results in yield reduction. Unpredictable rainfall has been reported to contribute about 36% to variation of yield difference between the rain-fed and irrigated fields. Among the drought resistance mechanisms, drought avoidance in genotypes with fibrous roots was recognized to be associated with drought resistance in soybean. Plant introduction PI416937 was shown to possess fibrous roots and has been used as a parent in breeding programs to improve soybean productivity. Little information is available on relative contribution and chromosomal location of quantitative trait loci (QTL) conditioning fibrous roots in soybean. To identify the genomic locations and genetic bases of this trait, a recombinant inbred line population was derived from a cross between PI416937 and 'Benning'. To detect associated QTLs, phenotypic data were collected and analyzed for 2 years under rain-fed field conditions. The selective genotyping approach was used to reduce the costs and work associated with conducting the QTL analysis. A total of five QTLs were identified on chromosomes Gm01 (Satt383), Gm03 (Satt339), Gm04 (Sct_191), Gm08 (Satt429), and Gm20 (Sat_299), and together explained 51% of the variation in root score. Detected QTLs were co-localized with QTLs related to root morphology, suggesting that fibrous roots QTL may be associated with other morpho-physiological traits and seed yield in soybean. Genetic dissection of the fibrous roots trait at the individual marker loci will allow for marker-assisted selection to develop soybean genotypes with enhanced levels of fibrous roots.
  • Authors:
    • Nwanguma, E. I.
    • Adebayo, O. S.
  • Source: Acta Horticulturae
  • Issue: 917
  • Year: 2011
  • Summary: A statewide survey of commercial irrigated pepper fields was conducted in Katsina, Nigeria to gain information on the incidence of diseases with wilt symptoms, their causative organisms, and the existing pepper production systems. Eighty fields were surveyed at different growth stages of pepper plants. Diseased plants with wilt symptoms occurred in all fields. The percentage wilt incidence in each field ranged from 50 to 100%. Field diagnosis, along with laboratory assays of wilted plants, revealed that the wilting was caused by Ralstonia solanacearum and Phytophthora capsici. The two pathogens were found in 88% of the fields and occurred together in 12% of the fields. Interviews conducted to assess farmers' practices, which contribute to pathogen damage, showed that successive planting of susceptible crops without land rotation may have contributed to the build up of the soil populations of the pathogens. The mode of irrigation also contributed to the pathogen control failures. Intercropping pepper with crops such as tomato ( Lycopersicum esculentum) and Solanum species did not reduce disease incidence in some areas. Results indicate the necessity for the adoption of integrated pest management strategies in pepper production in Katsina State, Nigeria.
  • Authors:
    • Peluzio, J. M.
    • Almeida, R. D. de
    • Afférri, F. S.
  • Source: Revista Ciência Agronômica
  • Volume: 42
  • Issue: 1
  • Year: 2011
  • Summary: The aim of this work was to evaluate the genetic divergence among twelve soybean cultivars under irrigated lowland conditions in south Tocantins State, Brazil, in the Companhia Brasileira de Agropecuaria (COBRAPE), at Formoso do Araguaia, TO, in the inter-cropping 2005. The experimental design employed was randomized blocks with twelve treatments and tree replications. The treatments consisted on the following cultivars: DM Vitoria, MG/BR 46 (Conquista), Suprema, BRS Pintado, DM 247, BRS/MG 68, BRS/MG Lideranca, BRS MG Seguranca, DM 339, BRS/MG Garantia, A 7002, and DM 309. The following characteristics were evaluated: grain yield, weight of hundred seeds, number of seeds per pod, number of pods per plant, number of days for flowering; number of days for maturation, plant height and height insertion of the primary pod. Genetic divergence was evaluated by multivariate procedures: generalized Mahalanobis distance, Tocher's agglomerative method of Tocher and nearest neighbor. The Tocher's method and nearest neighbor agreed among themselves. Number of days for the maturation (39.49%), weigh of hundred seeds (26.56%) and number of days for flowering (13.59%) were the traits that most contributed to the genetic dissimilarity. The presence of genetic variability allowed the identification of dissimilar cultivars with high average for the traits studied. BRS/MG Garantia * DM 339 and BRS/MG Garantia * MG/BR 46 (Conquista) hybridizations are promising for obtaining segregate populations with higher variability.
  • Authors:
    • Gautam, M.
    • Ambati, R. R.
    • Reddy, A. R.
  • Source: Indian Journal of Agronomy
  • Volume: 56
  • Issue: 4
  • Year: 2011
  • Summary: Field trials were conducted to validate farm pond sizes for supplemental irrigations during 2004-2011 at the Central Institute for Cotton Research, Nagpur (′21degrees09′N, 79degrees09′E.). Ten farm ponds 200 to 15,120 m 3 size resulted in a runoff storage of about 60, 75 and 28, 36, 58% (2007, 2010 and 2008, 2009, 2011) in normal and drought years at the end of August month. During actual drought the water availability was 0 and 18% only of the capacity designed in 2011 and 2008 July seedling droughts. Special recharging techniques like opening borewells/percolation tanks etc in under ground storages and using it with sprinkler irrigation during seedling droughts is the only option. Two supplemental irrigations at flowering stage along with application of deficient micronutrients on shallow and medium soils to Bt hybrid cotton ( G. hirsutum L.) resulted in increased seed cotton yield by 50% and 44%, which was verified during 2008 and 2009 seasons in Yeotmal district. The minimum economical catchment was found to be 21 ha or 0.7 ha m pond size, with which 25% and 50% area could be irrigated by conventional and alternate furrow/sprinkler irrigation respectively, with a payback period (PBP) of 2 years in Bt hybrid cotton. Rotational soybean ( Glycine max (L.) Merrill) could be irrigated to the extent of 16 and 33% catchment area with improved water use efficiency (WUE) from 250 to 500 kg/ha-cm for 1.5 and 3.5 years of pay back period (PBP) under conventional and sprinkler irrigation, respectively, during drought conditions. The same sprinkler and drip irrigation systems could also be used to irrigate subsequent wheat [ Triticum aestivum (L.) emend. Fiori & Paol] crop with a gravitational well, covering 14 and 57% of catchment area with WUE of 180 kg/ha-cm with a PBP of 11 and 21 years.
  • Authors:
    • Emerick, J. A. N.
    • Calazani, W. R.
    • Silva, C. F. da
    • Wendling, I. J.
    • Cunha, F. F. da
    • Araujo, R. A. S.
  • Source: Bioscience Journal
  • Volume: 27
  • Issue: 6
  • Year: 2011
  • Summary: The success in the use of pastures in silvopastoral systems depends on the understanding of the morphophysiological mechanisms and its interaction with the environment and of the management. It was aimed to evaluate the leaf appearance rate (LAR), leaf elongation rate (LER), stem elongation rate (SER), emerging leaf numbers (EmLN), expanded leaf numbers (ExLN), living leaf numbers (LLN), soil cover and plant height of Marandu grass intercropped with coconut. The experiment was mounted in a completely randomized arrangement, with six replications, in a split-plot design. The plots a treatments irrigated and not-irrigated and six rest periods in the split-plots (14, 21, 28, 35, 42 and 49 days). The irrigation provided increase in the soil cover, plant height, LER and SER of Marandu grass for the rest periods of 49 and 14 days, respectively. The rest periods provided linear reduction in the LAR and SER, and linear increase in the ExLN, LLN, soil cover and plant height of Marandu grass. The LER is bigger when rest periods used of 37 and 29 days, for Marandu grass irrigated and not-irrigated, respectively. It concludes that exactly in shade conditions, Marandu grass, when irrigated and submitted the biggest rest periods, provides to greaters morphogenic taxes and growth, indicating the potential of this fodder plant in integrated systems of production.
  • Authors:
    • Bandici, G. E.
    • Ardelean, I.
  • Source: Analele Universităţii din Oradea, Fascicula ProtecÅ£ia Mediului
  • Volume: 17
  • Year: 2011
  • Summary: The paper based on the research carried out during 2008-2010 in the long term trial placed in 1990 on the preluvosoil from Oradea. Three kind of crop rotation (wheat - monocrop; wheat - maize; wheat - maize - soybean) were studied in unirrigated and irrigated conditions. The smallest content of the protein from wheat grains were registered in the wheat monocrop both nonirrigated and irrigated variant. In the wheat-maize and wheat-maize-soybean crop rotation the values registered were significant statistically bigger than in wheat monocrop. Irrigation determined the decrease of the protein content.
  • Authors:
    • Yawson, D. O.
    • Obiri, S.
    • Yengoh, G. T.
    • Odoi, J. O.
    • Armah, F. A.
    • Afrifa, E. K. A.
  • Source: Mitigation and Adaptation Strategies for Global Change
  • Volume: 16
  • Issue: 3
  • Year: 2011
  • Summary: Desertification, climate variability and food security are closely linked through drought, land cover changes, and climate and biological feedbacks. In Ghana, only few studies have documented these linkages. To establish this link the study provides historical and predicted climatic changes for two drought sensitive agro-ecological zones in Ghana and further determines how these changes have influenced crop production within the two zones. This objective was attained via Markov chain and Fuzzy modelling. Results from the Markov chain model point to the fact that the Guinea savanna agro-ecological zone has experienced delayed rains from 1960 to 2008 while the Sudan savanna agro-ecological zone had slightly earlier rains for the same period. Results of Fuzzy Modelling indicate that very suitable and moderately suitable croplands for millet and sorghum production are evenly distributed within the two agro-ecological zones. For Ghana to adapt to climate change and thereby achieve food security, it is important to pursue strategies such as expansion of irrigated agricultural areas, improvement of crop water productivity in rain-fed agriculture, crop improvement and specialisation, and improvement in indigenous technology. It is also important to encourage farmers in the Sudan and Guinea Savanna zones to focus on the production of cereals and legumes (e.g. sorghum, millet and soybeans) as the edaphic and climatic factors favour these crops and will give the farmers a competitive advantage. It may be necessary to consider the development of the study area as the main production and supply source of selected cereals and legumes for the entire country in order to free lands in other regions for the production of crops highly suitable for those regions on the basis of their edaphic and climatic conditions.
  • Authors:
    • Selvakumar, T.
    • Balakumbahan, R.
    • Joshua, J. P.
  • Source: Indian Journal of Arecanut Spices - Medicinal Plants
  • Volume: 13
  • Issue: 4
  • Year: 2011
  • Summary: The importance, geographical distribution, cultivars, cultivation aspects (soil, climate, land preparation, propagation, planting material, raising of nursery, shade, transplanting, manures and fertilizers, irrigation, and intercropping), pest and diseases and their control, harvesting, crop yield, drying, distillation of oil, oil content and chemical constituents and storage of oil of patchouli ( Pogostemon patchouli [ Pogostemon cablin]) are briefly discussed.
  • Authors:
    • Gillen, A. M.
    • Reddy, K. N.
    • Bellaloui, N.
    • Fisher, D. K.
    • Mengistu, A.
  • Source: American Journal of Plant Sciences
  • Volume: 2
  • Issue: 5
  • Year: 2011
  • Summary: Information on the effect of planting date and irrigation on soybean [ Glycine max (L.) Merr.] seed composition in the Early Soybean Production System (ESPS) is deficient, and what is available is inconclusive. The objective of this research was to investigate the effects of planting date on seed protein, oil, fatty acids, sugars, and minerals in soybean grown under irrigated (I) and non-irrigated (NI) conditions. A 2-yr field experiment was conducted in Stoneville, MS in 2007 and 2008. Soybean was planted during second week of April (early planting) and second week of May (late planting) each year. Results showed that under irrigated condition, early planting increased seed oil (up to 16% increase) and oleic acid (up to 22.8% increase), but decreased protein (up to 6.6% decrease), linoleic (up to 10.9% decrease) and linolenic acids (up to 27.7% decrease) compared to late planting. Under I conditions, late planting resulted in higher sucrose and raffinose and lower stachyose compared with early planting. Under NI conditions, seed of early planting had higher protein (up to 4% increase) and oleic acid (up to 25% increase) and lower oil (up to10.8% decrease) and linolenic acids (up to 13% decrease) than those of late planting. Under NI, stachyose concentration was higher than sucrose or raffinose, especially in early planting. Under I, early planting resulted in lower leaf and seed B, Fe, and P concentrations compared with those of late planting. Under NI, however, early planting resulted in higher accumulation of leaf B and P, but lower seed B and P compared with those of late planting. This research demonstrated that both irrigation and planting date have a significant influence on seed protein, oil, unsaturated fatty acids, and sugars. Our results suggest that seed of late planting accumulate more B, P, and Fe than those of early planting, and this could be a beneficial gain. Limited translocation of nutrients from leaves to seed under NI is undesirable. Soybean producers may use this information to maintain yield and seed quality, and soybean breeders to select for seed quality traits and mineral translocation efficiency in stress environments.