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Kerala Agricultural University, Thrissur

The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively. Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively. On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs. In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc. During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU). Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.

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1982 - 198911990 - 19951
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Subject: Soil Science and Agriculture Chemistry × Author: Usha, P B × End date: 1995 × Type: Thesis ×
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    ThesisItemOpen Access
    Characterisation of soil organic matter in different soil types of Kerala
    (Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 1982) Usha, P B; KAU; Jose, A I
    Large number of surface soils representing the different districts of the state were analysed in order to work out precise relationships between organic carbon, total nitrogen and available nitrogen in these soils. The soils were categorized into different groups based on soil texture and content of organic matter. Relationships between different soil properties applicable to the different categories of soil were then examined. Fractionation of soil organic matter was carried out in a limited number of soils. Also the distribution of elemental components of soil organic matter was studied in soils selected for the fractionation of organic matter. Observations on the general characteristics of soil revealed that the content of organic carbon, total nitrogen and available nitrogen showed an increasing trend with increase in acidity of soil. In general more organic carbon was seen in fine textured soils. The total and available nitrogen content of soil increased with increase in content of organic matter. The content of available nitrogen showed significant and positive correlation with total nitrogen. Since the C/N ratio increased with increase in content of organic carbon it was necessary to predict the total and available nitrogen content of soil based on precise regression equations rather than depending on a conversion factor. On an average 10.82 per cent of the nitrogen in soil was extracted as available nitrogen. The C/aN ratio was positively and significantly correlated with organic carbon and total nitrogen while it was negatively correlated with available nitrogen. On an average the percentage of humic acid, fulvic acid and humin in soil organic matter were 28.28, 36.51 and 35.21 respectively. Of the 28.28 per cent humic acid, 9.60 per cent (of organic matter) was represented by hymatomelanic acid and the remaining 18.68 per cent by the insoluble fraction of humic acid. Humic acid was found to be significantly and positively correlated with total organic carbon, total nitrogen, clay and fulvic acid. Of the total fulvic acid 12.35 per cent (of organic matter) was represented by beta humus and the remaining by the soluble fraction of fulvic acid. Fulvic acid was positively and significantly correlated with organic carbon, total nitrogen, humic acid and clay. Humic acid and fulvic acid maintained a constant proportion irrespective of the variation in content of total organic matter. Humin was also positively and significantly correlated with organic carbon and total nitrogen. The mean phosphorus, sulphur and potassium content of organic matter were 0.051, 6.96 and 0.32 per cent respectively. The C/org.P, C/org.K, C/org.S, N/org.P, N/org.K, N/org.S, Org.P/org.K, Org.P/org.S and Org.K/org.S ratios were 1672.8, 94.1, 19.23, 205.81, 9.77, 2.91, 0.07, 0.008 and 0.0073 respectively.
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    ThesisItemOpen Access
    Evaluation of acidity parameters in wetland soils of Kerala in relation to nutrient availability
    (Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellayani, 1995) Usha, P B; KAU; Thomas, Varghese (Guide)
    Soil acidity is a major constraint in the wetland rice soils of the tropics, which has got aggravated in recent times with the introduction of high yielding varieties of rice and intensive use of fertilizers. Kerala State, with its unique geomorphology, climate, hydrology and other environmental factors has led to the formation of wetland soils with specific physico-chemical and mineralogical properties. These soils sustain a major part of the rice tracts in the State. Attempts to bring these lands under rice cultivation brought to light the intensity and severity of soil acidity in the natural as well as manmade wetlands of this region. Though studies have started way back in 1920 to tackle the problem of acidity and associated nutritional factors, a detailed study to unveil the intricate physico- chemical phenomena contributing to acidity and an economic and efficient methodology to alleviate the severity of acidity has not been attempted so far. Hence a study has been conducted to evaluate the acidity parameters in relation to nutrient availability in wetland rice soils of Kerala. Twelve major wetland rice soils have been identified and classified according to Soil Taxonomy. They belong to natural as well as manmade wetlands, some of them having been indigenously classified and known by vernacular names like Kari land (acid peat), Karapadam (riverine alluvium), Kayal land (lake bed sediments), Pokkali lands (saline acid), Kole lands (flood plain), Kaipad lands (saline marsh). Twelve profile samples representing the major wetland rice soils comprising an area of 6 lakh ha have been subjected to detailed investigations for morphological, physical, chemical, mineralogical and electro chemical parameters. Surface samples, each at a radial distance of 5 km from the twelve locations were collected and subjected to detailed studies to evaluate the acidity parameters and acidity generating factors. Studies were also taken up to observe the kinetics of pH and nutrient availability under submergence for different intervals of time. A comparative study on the efficacy of different methods of estimating the lime requirement was also taken up. From the detailed investigations on the evaluation of acidity parameters of wetland rice soils of Kerala, it has been observed that there exists a great extent of variation with respect to the severity of acitive acidity in the profile and surface samples. Barring Chittoor soils which were slightly alkaline, all the soils under study were acidic in reaction. The profile and surface samples of Kari soil of Thakazhi and Pokkali soil of Njarakkal recorded the highest active acidity with a dry soil pH around 3.2. The rating of these surface soils on the basis of active acidity was Kari ≥ Pokkali > Karapadom > Vellayani > Kayal > Kole > Wyanad > Pattabi > Kaipad > Karamana > Kattampally. However, with respect to the mean values of pH of profile samples the rating was Kari > Pokkali > Kole > Kayal > Karapadom > Vellayani > Wyanad > Pattambi > Karamana > Kattampally > Kaipad. All the soils having high active acidity recorded high exchange, non-exchange and potential acidity with significant correlation between them. It was observed that major part of potential acidity of wetland soils of Kerala was constituted by non-exchange acidity due to the preponderance of Kaolinite clay minerals and high content of sesquioxides. Highest values for potential acidity were recorded by 18-30 cm. of Kari and surface layers of Pokkali profiles. Based on mean potential acidity of surface samples the soils could be rated as Kari > Pokkali > Kayal > Karapadom > Kole > Pattambi > Kattampally > Vellayani > Kaipad > Karamana > Wyanad. HOWEVER, WITH RESPECT TO PROFILE SAMPLES THE SEQUENCE WAS Kari > Pokkali > Kayal > Karapadom > Kole > Wyanad > Vellayani > Kattampally > Pattambi > Kaipad > Karamana. From the correlations worked out, it was found that aqueous pH (1:1) under dry condition was a more reliable parameter for evaluating acidity in the wetland rice soils of Kerala than pH under wet condition or in salt solution, because this parameter gave more significant correlations with acidity generating factors and available nutrients. It was also observed that available sulphur determined both active and potential acidity rather than total sulphur in sulphur rich soils. Path coefficient analysis of acidity contributing factors indicated that exchangeable aluminium was the best parameter for measurement of acidity, 87 per cent of variation in exchange acidity, 57 per cent of variation in non- exchange acidity and 63 per cent of variation in potential acidity. Comparison of different methods for calculating lime requirement proved the superiority of exchangeable aluminium method for the wetland rice soils of Kerala. Lower rates of lime requirement were observed by this method for Kattampally, Wyanad, Karamana, Pattambi and Kaipad soils. Studies on submergence showed that wetland rice soils of Vellayani, Karamana, Karapadom, Kole, Kaipad, Kattampally and Wyanad do not require lime to raise the Ph for rice cultivation because all these soils attain a pH value of 5.5 within two weeks of submergence. Consequently there was increased availability of nitrogen, phosphorus, potassium, calcium, magnesium, iron, manganese and silica. However, zinc, copper and sulphur were found to decrease by prolonged submergence. The detailed investigations conducted under this study on the evaluation of acidity parameters of wetland rice soils of Kerala in relation to nutrient availability have unveiled many intricate phenomena of soil acidity which are of great theoretical and practical significance. Contrary to the conventional concept that liming is a must in all acid soils, the present study underlines the cheap and easy method of alleviating acidity of certain wetland rice soils by optimum submergence and scientific water management. Further the study has revealed the feasibility of liming in soils with severe acidity based on specific methods of estimating the lime requirement of soils. However it is necessary to confirm the results of these in- vitro studies by adequate field studies in specific wetland rice tracts of Kerala State.