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2012 - 20152
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Author: KAU × End date: 2019 × Start date: 2011 × Rating Count: 5 × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Socio-economic vulnerability and adaptive strategies to environmental risk: a case study of water scarcity in agriculture
    (Department of agricultural economics, College of horticulture, Vellanikkara, 2012) Rinu T, Varghese; KAU; Indira Devi, P
    Water stress is predicted as one of the most pronounced risk of climate change in countries like India. Kerala is reported as moving from wetness to dryness. Management of risks of climate change necessitates scientific estimates of the level of potential damage, accommodating for the vulnerability and adaptive mechanisms of the communities. The study entitled ‘Socio-Economic Vulnerability and Adaptive Strategies to Environmental Risk: A Case Study of Water Scarcity in Agriculture’ was undertaken with the objectives of measuring farmers’ vulnerability to water stress in agriculture and its impact on household welfare and to identify and assess the relative influence of various factors on the level of vulnerability. Further, short term and long term adaptive strategies to water stress among farmers of different socioeconomic conditions were also analysed. The most backward district of the state of Kerala, Wayanad was selected as the study area. Multistage random sampling method was adopted for sample selection. Nine panchayats from four Community Development Blocks were selected, from each of which, 15 farmers were selected. Thus the total sample size was 135. Primary data regarding the socio-economic status, land use pattern and production, sources of water for domestic use and irrigation, perceptions and adaptive strategies to water scarcity were gathered using pretested interview schedule. Indicator based approach was used for constructing the composite vulnerability index to assess the vulnerability level of the farmers. Logit model was employed to identify the factors influencing vulnerability. Apart from these, conventional tabular analysis was also used. The cropping pattern in Wayanad shows a clear shift in favour of commercial crops like arecanut, banana and rubber. The conversion of paddy lands for these crops was to the tune of 41 per cent during the last decade. The area under pepper shows a decline (54 %) and that of other commercial crops show an increase. Among other reasons, climate change is perceived as one of the major reasons for this decision by the farmers. The analysis of weather parameters and climate predictions for Wayanad also supports the farmer level observation. The rainfall and temperature pattern of the district during past years indicate an increasing level of water stress. Climate change models project very high variation in the rainfall pattern of the district in future years. An increase in the average annual rainfall coupled with lower levels of summer showers are predicted. By 2020, summer showers may decline to 43.6 mm as against the present, 70 mm. High intensity rains with low duration will be the major characteristic. A gradual increase in annual temperature by about 1.5ºC is also predicted. In this background, a composite vulnerability index considering social, economical and agronomic factors of the farmers was constructed to measure the vulnerability. More than 50 per cent of farmers were highly vulnerable and the proportion of the farmers in that group was found to be increasing during the past five years. An inverse relationship was observed between the land holding size and vulnerability level, three- fourth of the marginal farmers were vulnerable while most of the small and large farmers (41.27 % and 34.78 % respectively) belonged to the other group. Thavinjal panchayat of Manathavady block was found to be the most vulnerable and Muppainad and Vythiri panchayats of Kalpetta block were found to be the least vulnerable. The results of the logit model shows that five out of eight factors viz. diversity index, cropping intensity, percentage of irrigated area to total cropped area, net cropped area and education as having significant influence on the probability of an agricultural household being vulnerable, of which the diversity index and cropping diversity are the most influential factors. Farmers often have their own adaptive mechanism to cope with the water stress condition within the constraints. In general, adaptation strategies followed in domestic and agricultural sector can be classified into supply management strategies and demand regulating strategies or long term and short term strategies. The supply management programme includes those activities which ensure the steady supply of water and the demand side management mainly focus on more efficient use of available water resources and improving water resources. Among the respondents, a gradual shift from the dependence on external sources of water to owned sources has occurred. The dependence on external sources increases the time spent and drudgery of women folk in such households. Common adaptation strategies followed by the farmers include irrigation, varietal selection, mixed cropping, crop diversification, organic farming, soil and water conservation measures (mulching, earthen bunds and rain pits) and migration (geographical and sectoral). About 39 percent of the sample respondents were adopting irrigated farming and the average expenditure was found to be Rs 18187 per household which is nearly nine percent of the total household income. Only a few farmers were adopting micro-irrigation methods because of its high investment. This cost of adaptation, further reduces their consumption expenditure leading to household welfare loss. The study suggests research interventions in developing a sustainable cropping pattern and scientific validation with location specific studies on the impact of climate change on major crops. The need for empowering the farmers through technology, infrastructure, financial and extension support to adapt to water stress is also underlined. It highlights the importance of water resource development and the need for identifying the constraints in the adoption and develop/modify the technologies to suit local conditions. Further the implementation of weather based crop insurance programmes with localised meteorological stations as reference points is also stressed.
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    ThesisItemOpen Access
    Molecular marker development for cassava mosaic disease resistance using bioinformatics tools
    (Department of Plant Biotechnology, College of Agriculture, Vellayani, 2015) Ambu, Vijayan; KAU; Sreekumar, J
    The study entitled “Molecular marker development for cassava mosaic disease resistance using bioinformatics tools” was conducted at ICAR-CTCRI, Sreekariyam, Thiruvananthapuram during October 2104 to October 2015. The objectives of the study included development and evaluation of various SNP and SSR prediction pipelines, computational prediction and characterization of SNP and SSR in cassava, verification of SNP and SSR markers for cassava mosaic disease (CMD) resistant and susceptible breeding lines. The preliminary data set for the identification of SSR and SNP markers was obtained from the EST section of NCBI and the cassava transcript sequences from the Phytozome. A total of 120461 sequences was classified into 20 cultivars. The dataset was reduced to 14336 sequences after several pre-processing and screening steps. The resulting sequences were assembled and aligned using CAP3 and 2088 contigs were obtained. SNPs and SSRs were predicted from these datasets using respective prediction tools. The SNP prediction tools such as QualitySNP and AutoSNP were compared for their performance. Analysis was performed to identify the tool with the ability to annotate and identify more viable nonsynonymous and synonymous SNPs. The SSR prediction tools such as MISA and SSRIT was compared for their performance. Analysis was performed to identify the tool having the ability to predict more viable SSRs and the ability to classify them as mono, di, tri, tetra, penta, hexa and poly SSRs. Using QualitySNP, thirty nonsynonymous SNPs and twenty-six synonymous SNPs were identified. Using MISA, n 217 mono SSRs, 132 di SSRs, 139 tri SSRs, 3 tetra SSRs, 1 penta SSRs, 3 hexa SSRs and 42 complex SSRs were identified. Five sequences from identified SNPs and SSRs which have high hit percentage were selected for validation and primer designing for CMD resistant genes. These primers were validated using 5 resistant and 5 susceptible cassava varieties. Among the 10 primers after validation in wet lab, one SNP (SNP896) and one SSR (SSR 2063) primer was able to clearly differentiate between the resistant and susceptible varieties which can be used as potential markers in the breeding program for screening CMD resistance in cassava.