98 research outputs found

    Performance Evaluation Of Drip Irrigation System Under Onion Crop In Semi-Arid Region Of Eastern Rwanda

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    Efficient irrigation systems are needed not only to reduce environmental hazard but also to promote sustainable utilization of water resources. Drip irrigation is common irrigation systems that can save water and increase crop production by transferring small amounts of water frequently to the periphery of the roots of plants. So far, to establish a better irrigation system, it is necessary to improve onion growth, and yield. The present study was carried out to evaluate drip irrigation in 8 hectares for growing different crop particular onion vegetable at The Fresh Gate East Africa farm located in Rwamagana district, of Eastern province of Rwanda. A research study was conducted from January to May, 2020. The meteorological data were collected and analysed. Soil physical properties like soil texture, bulk density and infiltration rate were determined. The observations on water application through drippers and performance indicators were assessed. The results revealed that the rainfall in the study area is not sufficient in all decades of the months taken for crop period so irrigation is inevitable. The soil of the area is sandy loam and suitable for crop production. The performance indicators like Distribution efficiency (Ed), application efficiency (Ea), field emission uniformity (EUf), Absolute emission uniformity (EUa) and design emission uniformity (EUd) with the corresponding values of 91.66, 88.23%, 91.20%, 89.25% and 78.60% respectively were fitting in the standards of good to excellent performance. The value of coefficient of variance (Cv) with 0.085 falls in the category of marginal While statistical uniformity coefficient (SUC) with 91.5% presents good to perfect drip system. We conclude that drip irrigation has increased more 100% of onion production with the harvest of 12 Tons/Ha at FGEA Farm. It is therefore recommended that drip system is highly efficient irrigation system for Rwandan conditions and can easily be promoted through farmer’s sensitization and government support

    Application of FAO-CROPWAT software for modelling irrigation schedule of rice in Rwanda

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    The overall objectives of the present research are the study of weather, soil, discharges in the irrigation channels crop water requirement and irrigation scheduling of rice in Muvumba-8 marshland of Nyagatare district in Rwanda. The specific objective is to study the crop water requirement and irrigation scheduling of rice in the marshland. The average infiltration rate of the soil in the experimental field was 12.8 mm/hour. The average discharge in the primary channel is 7.94 m3/sec. The average reference crop evapotranspiration for the site was 3.89 mm/day. It varies from 3.51 to 4.38 mm/day. The maximum reference crop evapotranspiration was recorded in August and the minimum was May. The difference between maximum and minimum of reference crop evapotranspiration was observed to be 0.87 mm/day. CROPWAT derived the maximum effective rainfall of 80.3 mm in the month of October and the minimum of 20.9 mm during July. The total irrigation water requirement for rice crop for the season from Sept. to March was 412.7 mm. This low water requirement for rice is mainly due to higher effective rain fall in the experimental site from Sept to Dec. It was also inferred that the higher irrigation is needed from Dec to Feb because effective rainfall is lesser during that period. The moisture depletion pattern during the irrigation schedule varies from 59 to 71% with an average depletion of 64.8%. The net irrigation supplied to the field varies from 11.3 to 14.7 mm with an average net irrigation requirement 13.2 mm. The gross irrigation water requirement was varying from 16.2 to 21 mm with an average gross irrigation requirement of 18.96 mm. The average flow rate of water to the field was worked out to be 0.6 liter/sec/ha and it varies from 0.33 to 0.78 0.6 liter/sec/ha. The total gross irrigation was 906.9 mm and the total net irrigation was 634.8 mm.Keywords: CROPWAT, rice field, water requirement, irrigation schedul

    Characterization of Botrytis cinerea isolates from chickpea: DNA polymorphisms, cultural, morphological and virulence characteristics

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    Eight isolates of Botrytis cinerea, causal organism of chickpea from eight different locations of western and eastern Indo-Gangetic Plains (IGP) of India were analyzed for morphological, cultural, virulence and genetic variations. Characterization of virulence and genetic variations of the isolates was based on their pathogenicity against 40 selected chickpea genotypes and randomly amplified polymorphic DNA (RAPD) analysis, respectively. The isolates differed in their optimum growth, temperature, conidial formation and size of conidia on potato dextrose agar. Based on cluster analysis, the eight test isolates were separated into three pathotypes with two isolates from western and four from eastern IGP grouped together with >80% similarity. Based on cluster analysis of the RAPD banding patterns, genetic similarity of the isolates varied from 14-44%, and the isolates were separated into three groups. However, pathotypes variation detected among B. cinerea isolates could not be differentiated based on the RAPD markers examined.Keywords: Botryotinia fuckeliana, Botrytis gray mold, variabilit

    Subcutaneous Zygomycosis Due to Basidiobolus ranarum: A Case Report from Maharastra, India

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    Entomophthoromycosis is a rare entity. We hereby report a case of entomophthoromycosis in a three-year-old Asian child who presented with a painless, nontender, rapidly increasing large swelling on the thigh of six months duration, which was initially misdiagnosed as a soft tissue tumor and resected. The cause of misleading diagnosis was rapid growth of the lesion in a short duration of time, indicating the possibility of a tumor. Histopathological examination revealed an inflammatory lesion with aseptate fungal hyphae and the characteristic Splendore-Hoeppli phenomenon. Microbiological examination identified the fungus as Basidiobolus ranarum. Complete excision of the lesion followed by antifungal therapy was associated with complete recovery. Entomophthoromycosis should be considered early when children from endemic areas present with unusual, rapid-growing lesions of the subcutaneous region. In order to emphasize tumor-like presentation of zygomycosis, we are presenting this case

    Studies on green house gas emissions from rice field in Rwanda

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    The overall objective of this research is to estimate the Green House Gases (GHGs) emissions in different time of the day and to bring out the time of maximum and minimum GHGs emissions from the rice field. An experiment was conducted to estimate the GHGs emission from the rice fields of Muvumba P-8. Gas collection chambers were installed in 9 plots to collect the greenhouse gases. The gas samples were analyzed in Gas Chromatography and converted its results in to usable form. There was marked difference in the mean CO2 gas emission among the plots. The overall mean of CO2 gas emission among the experimental plots was 1950521 ÎĽg m-2 h-1. CH4 gas emission was high at 9 am and the minimum is at 3 pm among the mean gas production. Maximum CH4 gas emission at 9 am is due to the fact that during night time rice plant takes more CH4 and release the same due to ambient temperature rise at 9 am. The minimum CH4 gas emission at 3 pm is due to the fact that rice plant released all its CH4 during day time around 9 am to 3 pm and there was less CH4 in the rice plant to release at 3 pm. The mean of N2O gas emission at 6 am, 9 am, 12 noon and 3 pm of all the experimental plots was found to be 960.86 ÎĽg m-2 h-1. The mean N2O gas emission at 9am was found to be 995.82ÎĽg m-2 h-1. The important conclusion from the study is that N2O gas emission at 6 am and 12 noon are behaving similarly with decreasing trend. It was also found that N2O gas emission at 9 am and 3 pm are behaving similarly with decreasing trend.Keywords: Rice field, Green House Gases, emission, marshlan

    Potential for modulation of the hydrophobic effect inside chaperonins

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    Despite the spontaneity of some in vitro protein folding reactions, native folding in vivo often requires the participation of barrel-shaped multimeric complexes known as chaperonins. Although it has long been known that chaperonin substrates fold upon sequestration inside the chaperonin barrel, the precise mechanism by which confinement within this space facilitates folding remains unknown. In this study, we examine the possibility that the chaperonin mediates a favorable reorganization of the solvent for the folding reaction. We begin by discussing the effect of electrostatic charge on solvent-mediated hydrophobic forces in an aqueous environment. Based on these initial physical arguments, we construct a simple, phenomenological theory for the thermodynamics of density and hydrogen bond order fluctuations in liquid water. Within the framework of this model, we investigate the effect of confinement within a chaperonin-like cavity on the configurational free energy of water by calculating solvent free energies for cavities corresponding to the different conformational states in the ATP- driven catalytic cycle of the prokaryotic chaperonin GroEL. Our findings suggest that one function of chaperonins may be to trap unfolded proteins and subsequently expose them to a micro-environment in which the hydrophobic effect, a crucial thermodynamic driving force for folding, is enhanced

    Adaptation of grain legumes to climate change: a review

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    Humanity is heading toward the major challenge of having to increase food production by about 50% by 2050 to cater for an additional three billion inhabitants, in a context of arable land shrinking and degradation, nutrient deficiencies, increased water scarcity, and uncertainty due to predicted climatic changes. Already today, water scarcity is probably the most important challenge, and the consensual prediction of a 2–4°C degree increase in temperature over the next 100 years will add new complexity to drought research and legume crop management. This will be especially true in the semi-arid tropic areas, where the evaporative demand is high and where the increased temperature may further strain plant–water relations. Hence, research on how plants manage water use, in particular, on leaf/root resistance to water flow will be increasingly important. Temperature increase will variably accelerate the onset of flowering by increasing thermal time accumulation in our varieties, depending on their relative responses to day length, ambient, and vernalizing temperature, while reducing the length of the growing period by increasing evapotranspiration. While the timeframe for these changes (>10–20 years) may be well in the realm of plant adaptation within breeding programs, there is a need for today’s breeding to understand the key mechanisms underlying crop phenology at a genotype level to better balance crop duration with available soil water and maximize light capture. This will then be used to re-fit phenology to new growing seasons under climate change conditions. The low water use efficiency, i.e., the amount of biomass or grain produced per unit of water used, under high vapor pressure deficit, although partly offset by an increased atmospheric CO2 concentration, would also require the search of germplasm capable of maintaining high water use efficiency under such conditions. Recent research has shown an interdependence of C and N nutrition in the N performance of legumes, a balance that may be altered under climate change. Ecophysiological models will be crucial in identifying genotypes adapted to these new growing conditions. An increased frequency of heat waves, which already happen today, will require the development of varieties capable of setting and filling seeds at high temperature. Finally, increases in temperature and CO2 will affect the geographical distribution of pests, diseases, and weeds, presenting new challenges to crop management and breeding programs
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