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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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Subject: Soil Science and Agriculture Chemistry × Author: Anila Kumar, K × End date: 2001 × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    Nitrogen losses from the rice soils of Kerala with special reference to ammonia volatilization
    (Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 1989) Anila Kumar, K; KAU; Rajaram, K P
    In order to get a deeper insight in to the N dynamics of selected submerged rice soils, an investigation entitled “Nitrogen losses from the rice soils of Kerala with special reference to ammonia volatilization” was carried at the Regional Agricultural Research Station, Pattambi during 1985 – 87 with the following objectives. 1. To estimate the magnitude of ammonia volatilization losses from submerged rice soils, representing major rice growing tracts of Kerala. 2. To study the factors which are responsible for accelerating the rate of ammonia volatilization under flooded soil conditions. 3. To evaluate the effect of submergence, organic matter application, complementary effect of P and K on ammonia volatilization from the rice soil ecosystem. 4. To identity suitable N carriers capable of reducing the loss of N due to ammonia volatilization from submerged paddy soils. 5. To find out the effect of continuous application of organic and inorganic manures in lateritic submerged paddy soils on the quantum of N loss through ammonia volatilization. 6. To find out the transformations and extent of mineralization of applied urea. With these objectives, in view, a serious of laboratory incubation studies, followed by pot culture trials were carried out and the results were finally verified under field experiment also. Besides these, the plots of permanent manorial trial (dwarf indica) were utilized for estimating the N loss through ammonia volatilization on long term application of organic manures and inorganic fertilizers. In the incubation study for estimating the magnitude of N loss though ammonia volatilization, eight rice soils of kerala viz., sandy, karapadam, kayal, kari, pokkali, kole, poonthalpadam and laterite soils representing the major rice growing tracts of Kerala were incubated with no N and 27 g N m-2 as urea. Air train and acid trapping device was utilized to collect the volatilized ammonia. The results showed that sandy soil collected from Onattukara region registered an increased N loss through ammonia volatilization, whereas in the kole soil of kattukampal, the process was retarded to the lowest level. More than 75 per cent of the volatilization loss was observed within 9 days after urea application. Significant negative correlation was observed between ammonia volatilization and organic matter content, clay fraction and cation exchange capacity of the soil, whereas the coarse sand fraction showed significant positive correlation. Soil sterilization had little influence on ammonia volatilization in any of the soil under study. Another incubation study to assess the impact of quantity of urea applied on the quantum of N loss through ammonia volatilization was carried out using four soil types (sandy, kayal, poonthlpadam and laterite soils) with four rates of N application (9, 18, 27 and 36 g N m-2 ). The results indicated that the N loss through ammonia volatilization had a positive relationship with increased rates of urea application, though not linear. The complementary effect of phosphorus and potassium on the extended loss of N through ammonia volatilization was estimated in another incubation study utilizing the same four soil types with treatment as N alone, N and P, N and K and N, P, K @ 27:13.5:13.5 g N, P, K m-2 respectively as urea, superphosphate and muriate of potash. The results revealed that combind application of urea and muriate of potash was found to be significantly better in reducing the volatilization loss to be significantly better in reducing the volatilization loss of ammonia compared to the treatments, N alone and N and P. The incubation study to find out the influence of depth of submergence on the rate of volatilization of ammonia was conducted using the same soil types and four treatments (soil saturation, 5,10 and 20 cm submergence). The results showed that the soil samples maintained at saturation point recorded double the values for ammonia volatilization, compared to samples kept under submergence of 20 cm depth. The effect of application of organic matter on N loss through ammonia volatilization was studied in the same four soil types with the treatments as no organic matter, 0.25, 0.50, 0.75 kg organic matter m-2 as farm yard manure. The results indicated that application of organic matter was found to reduce volatilization losses considerably in all the soils studied and the lowest value recorded was for the treatment receiving farm yard manure @ 0.75 kg m-2. The relationship between N sources and the extent of volatilization of ammonia was investigated in another incubation study employing the same four soil types and ten different N carriers to supply 27 g N m-2. The relative efficiency of different N carriers in reducing the ammonia volatilization loss was in the order sulphur coated urea > urea mudball > gypsum coated urea > rock phosphate coated urea = neem cake coated urea = ammonium sulphate = ammonium chloride > urea : coconut pith: soil = urea. The pot culture study to trace the pathway of transformation and extent of mineralisation of urea under flooded soil condition consisted of three soil types (laterite, kari and poonthalpadam soil) and two levels of N (no N and 90 kg N ha-1 as urea). The rate of mineralisation of applied urea followed the soil reaction and the mineralisation stopped at the stage of NH+4 formation and hence chances of N loss through denitrification is meagre, unless the soil is aerobic. The second pot culture experiment was conducted with a view to identify the different ways that result in minimum loss of N through ammonia volatilization in sandy and laterite soils. The study showed that the decreasing order of N loss through ammonia volatalization from different N carriers followed the order, urea basal = urea; coconut pith: soil = coaltar coated urea = gypsum coated urea = rock phosphate > coated urea > urea split > urea super granule > urea mudball > sulphur coated urea. The five treatments selected from this experiments viz., urea split, urea mudball, urea super granule, gypsum coated urea and rock phosphate coated urea on reduced ammonia volatilization and high grain yield were compared in another pot culture trial and finally it was verified under field experiments in trial and finally it was verified under field experiments in laterite soil. The results revealed that urea mudball placement in the anaerobic layer of soil was found to reduce the n loss through ammonia volatilization to negligible level. Treatments with surface application of rock phosphate coated urea and urea in split dose ranked second and third position respectively in reducing the volatilization losses. Treatment receiving split application (top dressing of urea at 20 and 40 DAT) reduced ammonia volatilization considerably. Significant positive correlation was found between the cumulative N loss through ammonia volatilization and flood water pH measured at 0800 hrs and 1400 hrs, flood water NH4 – N content and flood water bicarbonate content. The pH of flood water measured at 1400 hrs were significantly higher than the value recorded at 0800 hrs and highest diurnal variation was observed for treatment with urea super granule deep placement. The urea super granule deep placement treatment resulted in increased grain yield in both the pot culture trials and field experiment. However, in field experiment the effect of different N carriers on grain yield was found to be uniform. The periodical N uptake by plants as well as N accumulation in grain and straw at harvest were found to be higher in the case of treatments receiving USG deep placement and urea split application. The effect of long term application of organic and inorganic nitrogen sources in soil on the rate of n lose through ammonia volatilization was studied utilizing the permanent manorial experiments. Plots receiving combined application of cattle manure + green leaves + NPK @ 45:45:45 kg N, P2 o5, K2 o as ammonium sulphate, super phosphate and muriate of potash were recorded the lowest value of n loss via ammonia volatilization when compared to other treatment plots.