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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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ThesisItem Open Access Response of chilly to plant growth promoting rhizobacteria fluorescent pseudomonads(Department of Agronomy, College of Agriculture, Vellayani, 2003) Anu, V; KAU; Elizabeth Syriac, KThe research project entitled 'Response of chilli (Capsicum annuum L.) to plant growth promoting rhizobacteria fluorescent pseudomonads' was carried out as two investigations viz., a pot culture trial and a field study at the College of Agriculture, Vellayani, during July 2002 to April 2003. The study was conducted on chilli cultivar, Jwalasakhi. The pot culture study was aimed at evaluation of fluorescent pseudomonads isolates for growth promotion and yield in chilli. The treatments consisted of five different isolates of fluorescent pseudomonads (PI, P5, P14, P22and KKI6). The trial was laid out in completely randomised design with four replications. Among the five isolates tested, isolate P22 was adjudged as the best one for growth promotion and P I for disease resistance. As far as yield and economics are concerned, these two isolates were found to be on par. Thus a dual culture of Tsolate P22 and PI was selected for further field study. The objective of the field study was to assess the suitability of the best isolate of fluorescent pseudomonads as a biofertilizer either alone or in combination with Azospirillum along with different doses of NPK . fertilizers on growth and productivity of chilli. The field study was laid out in factorial randomised block design with three replications. The different treatments included three different levels of NPK (75 per cent (56.3 : 30 : 18.8 kg ha"), 100 per cent (75 : 40 : 25 kg ha') and 125 per cent (93.8 : 50 : 23.5 kg ha-I) of the recommended dose of NPK as per POP) and four biofertilizer treatments (Fluorescent pseudomonads, Azospirillum; Fluorescent pseudomonads + Azospirillum and no biofertilizers). The abstract of the result is furnished below. r I~ All the growth characters increased significantly with graded doses or PK. Combined inoculation of fluorescent pseudomonads and Azospirillum was the most superior one among biofertilizer treatments. Similar trend was also observed for yield attributing characters. However with regard to marketable fruit yield, all the levels of NPK fertilizers tested were statistically on par. With respect to biofertilizer application, combined inoculation (7.75 ha") was on par with fluorescent pseudomonads application (7.56 t ha-I). Compared to control of no biofertilizer treatment, Fluorescent pseudo monads + Azospiriflum increased fruit yield by 46.69 per cent. Among the treatment combinations, 75 per cent of the recommended dose of NPK (56.3 : 30 : 18.8 kg ha-I) + Fluorescent pseudomonads + Azospirillum produced significantly higher yield (8.74 t ha-I) and ensured a saving of 25 per cent of recommended dose of NPK. 100 per cent POP + Fluorescent pseudomonads application was on par with this treatment. At 125 per cent of the recommended dose of NPK (93.8 : 50 : 23.5 kg ha I) microbial count in the rhizosphere was significantly lower and fruit rot incidence was significantly higher. Biofertilizer application significantly increased microbial count and reduced disease incidence. 75 per cent of recommended dose of PK + Fluorescent pseudomonads + Azospirillum was rated as the most economically viable treatment combination, with a net profit and benefit-cost ratio of Rs. 59328 ha-I and 1.82 respectively.ThesisItem Open Access Integration of nutritional inputs for improving rice productivity in laterite soils(Department of Agronomy, College of Horticulture, Vellanikkara, 2003) Jinappa, Halingali; KAU; Usha, K EA study on "Integration of nutritional inputs for improving nee productivity in laterite soils" was taken up during 2001-2003 at the College of Horticulture, Vellanikkara The experiment consisted of 17 treatments including two sources of organic manure and two levels of nutrition with combinations of lime and silica to develop a cost effective, high yield and sustainable production technology for rice by identifying the components of good management. The treatment .receiving poultry manure with 90 kg ha" of fertilizer N and 500 kg ha" of silica recorded the maximum height productive tillers, •number of spikelets per panicle and thousand grain weight which . contributed to the maximum grain yield 0[7004 kg ha". An increase in 1680 kg grain yield and 1087 kg straw yield than the package of practices recommendation of Kerala Agricultural University appear to be due to the application of Silica, substitution of cow dung by the poultry manure and increased dose of N with an organic: inorganic ratio of 1 :2.25, increased dose ofK and reduced dose ofP. Cow dung contains Fe, Zn and Cu in toxic levels to rice. Poultry manure has the content of these elements in far less quantities but has higher Ca content . which helps in reducing the uptake of unfavourable elements by the rice plants. Increase in'the level of K application @120 kg ha' has recorded 1387 kg ha" more grain than the present recommendation of 35 kg ha" and the uptake of K by the plants are far above the applied levels. This suggests that the present recommendation of35 kg ha' ofK has to be enhanced up to 120 kg ha" to prevent the soil degradation. It is also seen that the rice plants absorb only around 20 kg P and hence the P recommendation can be reduced from 35 kg to 20 kg ha". There was no apparent effect when lime and silica were applied together but individually they could improve the yield. The number of weeds and the incidence of pests and disease were less in thetreatment plots, which revealed the influence of soil ameliorants in impa~ing resistance in the rice pants. TIle. results of the present study indicate that the failure of rice plants to respond to higher doses of fertilizer N, appears to be because of the unfavourable organic: inorganic' ratio. A ratio of 1 :2.25 was found to be beneficial to nullity the unfavourable chemical effects of fertilizer N.ThesisItem Open Access Standardisation of mat nursery for rice(Department of Agronomy, College of Horticulture, Vellanikkara, 2003) Rajesh, G; KAU; Jaikumaran, UA field experiment was conducted during May to September 2002 at the Agricultural Research Station, Mannuthy, Thrissur to develop a suitable production package for rice mat nursery, evaluate it under mechanical transplanting and develop it as a substitute for conventional nursery for manual planting. The s~dy consisted of three experiments. (J) Raising of sixteen types of mat nurseries using . . four different media in two ratios under two systems (dry and wet) and its evaluation. (II) Mechanical transplanting of these sixteen types of mat nurseries along with manual planting of conventional nursery and crop performance study. (Ill) Manual transplanting of sixteen types of mat nursery along with conventional nursery and crop evaluation. Experiment-I was designed in GRD, while experiment-II and experiment-Ill were laid out in Randomised Block Design, with two replications each. Rice variety Kanchana, was tried in the experiment. Results revealed that soil+ cow dung in the ratio 2: 1 in the mat produced taller seedlings and coir pith compost produced shorter seedlings. Presence 'of cow dung produced dark green seedlings with maximum number of healthy and minimum number of weak seedlings. Soil+ cow dung in the ratio 2:1 produced heavy mats under both systems. Presence of chaff in the media resulted in stronger mats. The performance of the transplanter, as it is a fixed parameter for the machine was unaltered by the different media and systems of nursery. But generally, the , '. number of missing hills was lower under dry system, compared to wet system. In case of experiment-Il, a higher plant population of 65 hills m-2 was seen associated with the crop raised under manual planting using conventional nursery. But the same crop produced a significantly lower number of tillers hill-1 throughout its growth period and the crop had 9.5 tillers nnr', at the time of harvest. The physiological growth attributes, observed through CGR, RGR and NAR was distinctively lower for the manuaIIy planted crop using conventional nursery in the initial stages of growth, but the trend disappeared in the later stages, indicating a uniform rate of growth. The insect pest attack was uniform without any variation due to treatments. Incidence of BLB was higher in case of mechanically planted crop using soil+ coir pith compost in 2: 1 ratio under dry nursery and soil+ coir pith raw in 2:] ratio under wet nursery. Among the yield components, number of 'panicles m-2 and test weight were not altered by the treatments. The maximum number of filled ,grains panicle" was seen in case of soil+ cow dung in the ratio 2:] ,as the media under dry system (61). However, the final grain and straw yield remained unaffected due to the various treatments with a mean value of 4344 and 7464 kg ha" respectively. The NPK content of the grain and total uptake ofP and K by the crop were influenced by the various treatments. Under dry system soil+ coir pith raw and soil+ chaff in the ratios 2: 1 and in wet system soi1+ cow dung in the ratio 1:2 and soil+ coir pith compost in the ratio 2: 1 were economically superior and can be the mat nursery media for mechanical transplanting. The use of mat nursery instead of conventional nursery did not prolong the time required for manual planting. Conventional nursery recorded a lower tiller production (8.8 at the time of harvest). Similar level of tiller production was seen in cases of soil+ chaff in either of the ratios and soil+ coir pith raw in the ratio 1:2. The pest and disease incidence, except rice bug, did not show any discrimination between the treatments. SoiI+ chaff in the ratio ]:2 under dry system had a higher population of bugs (2.7 per hill). Soil+ coir pith raw in the ratio 2: 1 under both the systems had the highest number of panicles m-2 i.e., 352 and 341, respectively. Conventional nursery had the lowest number of filled grains panicle" (31). The grain yield was unaffected, due to treatments and the mean grain yield was 4441 kg ha-I. Straw yield was influenced by the different treatments. A very low harvest index value of 0.3 was recorded for the crop. Crop raised using conventional nursery had a very low B:C ratio (l.05) and all mechanically planted crops had higher B:C ratio than this. As the grain yield was not affected due to the various treatments, the selection of mat should be based basically on economic consideration. Soil+ coir .pith raw as well as soil+ chaff in the ratio of 2: 1 under dry system, and soil+ cow dung in the ratio] :2 and soi1+ coir pith compost in the ratio 2:], under wet system could be a better option for mechanical transplanting based on the economics. Soil+ cow dung in 1:2 ratio and soi1+ chaff in 2: 1 ratio under both systems, and soil+ coir pith raw in 1:2 ratio under dry system and soil+ coir pith raw in 2: 1 ratio under wet system were found economically suitable. for manual planting.ThesisItem Open Access Weed management in semi- dry rice intercropped with green manure crops(Department of Agronomy, College of Horticulture, Vellanikkara, 2003) Resmy, O N; KAU; Jose MathewAn investigation was conducted during the kharif season of 2002 at Agricultural Research Station, Mannuthy to formulate weed management practices in semi-dry rice intercropped with green manure crops. Fourteen treatments were laid out in RBD with three replications involving combinations of two green manure crops (cowpea and horsegram) for in situ green manuring and six weed management treatments (butachlor, pendimethalin, pretilachlor, anilofos, handweeding and control) in addition to rice monocropping . . Results of the study revealed that an integrated strategy encompassing the application of pre-emergence herbicides and intercropping of green manure crops was successful from the point of view of weed management, organic manure addition and crop yield in semi-dry rice. Among the fourteen treatments tried, the highest yield of grain and straw was recorded by monocropped rice with hand weeding (T 13) which was on par with treatments intercropped with horsegram (Ts) and cowpea (T2), both receiving pendimethalin application. Intercropping with horsegram encouraged better growth of rice over cowpea. Averaging the grain yield of rice in intercropping treatments, it was found that concurrent growing of horse gram has significant superiority over cowpea. Comparing the unweeded plots with cowpea or horse gram intercropping and rice monocrop, it was observed that intercropping reduced the weed count to the extent of 42.8 to 56.8 per cent upto 60 DAS and cowpea was found superior in suppressing the population of weeds. The contribution of N, P and K by cowpea at the time of self decomposition was almost double that of horse gram, leading to an increased soil fertility status. Pendimethalin, pretilachlor and butachlor can be used safely both in rice + cowpea and rice + horsegram cropping systems and they favoured growth and yield of green manure crops and rice, apart from their superior weed control efficiency.ThesisItem Open Access Identification of drought tolerant cocoa types(Department of Agronomy, College of Horticulture, Vellanikkara, 2005) Binimol, B; KAU; George Thomas, CExperiments were conducted at the college of Horticulture, Vellanikkara to investigate the drought tolerant characteristics of the most promising cocoa varieties and accessions. The investigation involved a two-stage screening of cocoa seedlings and budlings and monitoring of their field grown plants. As the first step, a preliminary screening was done on six month old seedlings and budlings of ten cocoa cultivars released from Kerala Agricultural University and twenty promising accessions. A secondary screening of cocoa cultivars/accessions selected from the preliminary screening was then conducted. Simultaneously, field monitoring of cocoa trees of the varieties selected from the primary screening was also done. From the preliminary screening, seven apparently tolerant varieties were selected for secondary screening in both seedlings and budlings based on higher RWC and DWF, lower percentage of dried leaves and longer duration of life under during moisture stress. Three apparently sensitive verities were also selected based on opposite values of the above characters. Varieties identified in the preliminary screening were subjected to a secondary screening under three moisture regimes of no irrigation , watering once in five days (life saving irrigation), and regular watering. Observations on physiological parameters such as relative leaf water content, dry weight fraction, leaf drying percentage, number of days taken for complete drying, stomatal conductance, transpiration rate, leaf water potential, chlorophyll ‘a’, ‘b’ and total chlorophyll, chlorophyll stability index, leaf area per seedling, membrane stability, relative injury; growth characters like plant height, collar girth, number of leaves and total biomass; biochemical characters such as proline content and nitrate reductase activity were recorded. After conducting a cluster analysis, the varieties with high RWC, DWF, total chlorophyll content, leaf water potential and proline content; low stomatal conductance, transpiration rate and leaf area during water stress were rated as drought tolerant and with opposite characters as drought sensitive. Based on these, in seedlings; the varieties M 13.12, GII 19.5 and GVI 55 were ranked as moisture stress tolerant and GVI 61, GV 50 and GI 4.8 as sensitive under no irrigation. In budlings, the varieties GI 4.8 and GII 19.5 were selected as drought tolerant and GIII 4.1, GVI 51 and GII 12.3 as drought sensitive under no irrigation Important characters were also monitored in 16-year old clonal trees of the seedlings/budlings of the varieties selected from primary screening. Transpiration rate, stomatal conductance, leaf water potential, stomatal frequency, leaf thickness, bark thickness and soil moisture content were recorded during summer. The varieties GVI 61, M 13.12 and GI 4.8 showed drought tolerant features. The accession M13.12 (CCRP2) showed drought tolerant features in secondary screening of seedlings and field performance. The accession GVI 51, which showed sensitivity to moisture stress in seedlings (but tolerant in budlings) under secondary screening, was showing similar behavior of sensitivity in field grown plants. The study shows the possibility of exploiting drought tolerant features of cocoa varieties/accessions. However, final conclusions are difficult to be drawn as only 10 accessions were subjected to secondary screening and field monitoring, and data for only one year were collected. In the light of the promising results obtained, screening trails involving more number of varieties/accessions have to be conducted and monitored for more number of years to get consistent values.ThesisItem Open Access Integrated weed management in lowland rice(Department of Agronomy, College of Agriculture, Vellayani, 2004) Seema, V; KAU; Janardhanan Pillai, SA field experiment was conducted at Cropping Systems Research Centre (CSRC), Karamana, Thiruvananthapuram to evolve a suitable integrated weed management practice for lowland nee. The study was conducted during the viruppu season of 2003. The field experiment was laid out in randomised block design having three replication with twelve treatments. The treatments include different herbicides in combinations, herbicides + hand weeding, hand weeding twice and unweeded control. Butachlor, 2,4~D, pretilachlor, anilofos + 2,4-DEE, anilofos, ethoxysulfuron, metsulfuron methyl and chlorirnuron- ethyl were the different herbicides used in the experiment. The rice variety used for the experiment was Kanchana. The results of the study revealed that grasses, broadleaved weeds and sedges competed with the rice crop. Different weed management practices significantly influenced the intensity and distribution of weeds ... The lowest dry matter of weeds was recorded by anilofos + ethoxysulfuron followed by one hand weeding which was on par with anilofos -+ ethoxysulfuorn alone. All the weed management treatments resulted in improved yield attributes and higher grain yield compared to weedy check. The plots treated with anilofos + ethoxysulfuron followed by hand weeding at 40 DA T recorded the highest grain yield. This treatment resulted in enhanced plant height, number of productive tillers un', LAI and nutrient uptake of rice. The yield attributes and grain yield were significantly increased by this treatment. The total weed population, weed dry matter production and nutrient removal by weeds were also reduced and weed control efficiency was increased by this treatment. Unweeded control recorded the lowest gram yield. No herbicide used in this experiment resulted m residual toxicity after the cropping season. Manual weeding is expensive, laborious and time consummg. Labour non-availability at peak crop season for weeding also poses great threat. Readymix application of anilofos + 2,4-DEE (T3) resulted in highest B:C ratio of 1.41 and butachlor + 2,4-D (T,) with 1.40. Pre-emergence application of anilofos + ethoxysulfuron followed by one hand weeding at 40 DA T (T 8) was the most remunerative treatment.ThesisItem Open Access Nutrient management of guinea grass (Panicum maximum J.) under open and shaded conditions(Department of Agronomy, College of Agriculture, Vellayani, 2004) Lekshmi, P; KAU; Lakshmi, SA field experiment was conducted at the Instructional Farm, College of Agriculture, Vellayani, Thiruvananthapuram, Kerala state to find out the nitrogen and phosphorus requirement for guinea grass (Panicum maximum J.) under zero and 50 per cent shade levels. The influence of shade levels, nitrogen and phosphorus application on growth parameters, fodder yield, quality of produce, physiological parameters, uptake of nutrients, chemical properties of soil and economics was investigated. Two levels of shade (0 and 50 per cent), three levels of nitrogen (100, 200 and 300 kg ha") and three levels of phosphorus (25, 50 and 75 kg ha") were combined to form eighteen treatment combinations. The experiment was laid out in split plot design with three replications. Results of the experiment revealed that lower levels of shade as well as higher- levels of nitrogen and phosphorus had significant positive influence on improving the fodder production potential of guinea grass. The lower levels of shade and higher doses of nitrogen and phosphorus were found to increase significantly the growth parameters namely number of tillers and leaf: stem ratio and physiological parameters like leaf area index, CGR, RGR and NAR. , Lower levels of shade and higher doses of nitrogen and phosphorus registered maximum green fodder yield in all the five harvests. Total green fodder yield was also highest at open and at higher levels of nitrogen and phosphorus. Similar results were obtained in the case of dry fodder yield also. Quality parameters of the forage significantly improved as shade progresses. Higher levels of nitrogen and phosphorus registered higher crude protein and chlorophyll contents and lower crude fibre content. The nutrient content of plant showed a significant increase with increasing levels of shade while the nutrient uptake showed a significant increase with lower levels of shade. Application of nitrogen and phosphorus significantly increased the content and uptake of nitrogen, phosphorus and potassium. There was a significant increase In available phosphorus and a decrease in available potassium content of the soil with increase in shade levels. Application of nitrogen significantly increased the nitrogen content of the soil while reduced phosphorus and potassium content of the soil after the experiment. Phosphorus levels also significantly increased the nitrogen and phosphorus content but potassium content of the soil after the experiment showed a parabolic type of response. Lower levels of shade with higher dose of nitrogen and phosphorus registered highest net returns and benefit cost ratio. But economic yield was obtained in shade intensity upto 50 per cent.ThesisItem Open Access Evaluation of establishment methods and AMF application on growth and yield of rice(Department of Agronomy, College of Agriculture, Vellayani, 2004) Jayakiran, K; KAU; Sajitharani, TAn experiment was conducted at College of Agriculture, Vellayani during kharif season (June - September 2003) to evaluate the efficiency of different planting methods and AMF application en the establishment, growth and yield attributes of rice. The experiment was laid out in split plot design with five replications. The main treatments were seedling , throwing, machine planting and line transplanting methods. The subplot treatments consisted of AMF application and without AMF application. Maximum establishment as noticed in line planting. More root activity, plant height, leaf area index, dry matter production and tillers were observed in seedling throwing method. Days to 50 per cent flowering was minimum in machine planting. Higher number of filled grains per panicle was observed in line planting. Higher number of productive tillers, panicles m-2 and straw yield was observed in seedling throwing method. Higher grain yield was observed in seedling throwing and line planting methods. Maximum harvest index was noticed in line planting. Higher uptake was noticed in seedling throwing method. AMF inoculated plants show~d supenor trends in establishment plant height, leaf area index, drymatter production, number of productive tillers, panicles m ", filled grains panicle.", 1000 grain ,eUEbt. grain yield and straw yield. Higher gross return and net return was observed in seedling ing method. In machine planting and see~ling throwing there was high labour saving compared to line planting .. High B : C ratio, gross turn and net return were observed in AMF inoculated plants. Machine planting of seedlings raised in AMF inoculated mat nursery, at a spacing of 30 x 10 cm followed by seedling throwing of MF inoculated seedlings recorded higher B : C ratio.ThesisItem Open Access Integrated nutrient management for short duration Cassava in lowlands(Department of Agronomy, College of Agriculture, Vellayani, 2003) Pamila Vimal, Raj; KAU; Kumari Swadija, OAn investigation entitled "Integrated nutrient management for short duration cassava in lowlands" was undertaken in the Instructional Farm, College of Agriculture, Vellayani from September 2002 to April 2003 to develop an integrated nutrient schedule for short duration cassava in lowlands and to work out the economics of cultivation. The treatments consisted of factorial combinations of two varieties of cassava (Sree Vijaya and Kariyilapothiyan), three sources of organic manure (farmyard manure, poultry manure and coir pith compost) and three levels of nitrogen (50, 75 and 100 kg N ha-I). The trial was laid out in 32 x 2 asymmetrical confounded factorial design with two replications confounding VMN in replication J and MN in replication II. A uniform dose of 50 kg P20S ha' and 100 kg K20 ha-' was applied to all the plots. In general, the local var. Kariyilapothiyan recorded superior values of growth characters like plant height, leaf number and leaf area index. Among organic manures, farmyard manure produced higher values of growth characters. But total dry matter production was not influenced either by varieties or by sources of organic manure. Levels of N had profound influence on growth characters and 75 kg N ha-' was found superior in the case of both varieties. Varieties exhibited no variation in yield components except length of tuber. The improved var. Sree Vijaya produced longer tubers than the local variety. The yield components except tuber weight per plant did not vary with the source of organic manure. Poultry manure recorded the highest value of tuber weight per plant. Nitrogen @ 75 kg N ha" recorded higher values of yield components. The performance of both varieties In terms of tuber yield, top yield and utilization index was found similar. Among organic manures, the highest tuber yield was recorded by poultry manure which was on par with farmyard manure but superior to coir pith compost. At the same time the effect of farmyard manure was on par with coir pith compost. The top yield was not influenced by the source of organic manure but utilization index exhibited the same trend as that of tuber yield. The tuber yield increased when N level was increased from 50 to 75 kg N ha-I but decreased with further increase in the level of nitrogen. Top yield increased with increase in the level of nitrogen. Application of75 kg N ha" registered the highest utilization index. Neither varieties nor sources of organic manure recorded any significant variation in starch content of the tuber. But the local variety recorded higher protein content and lower HeN content than the improved variety. Poultry manure treated plants registered the highest protein content and the lowest HeN content. Application of 75 kg N ha" was sufficient for obtaining higher starch and protein contents. The HeN content increased with increase in the level of nitrogen though it was within permissible limits. The improved var. Sree Vijaya obtained higher scores for taste than the local variety. The taste of the tuber was not affected by the source of organic manure. Maximum score for taste was recorded by 75 kg N ha'. The cooking quality of the tuber of both varieties was judged as good. Uptake of Nand K was not influenced by varieties. But in the case of P uptake, the var. Sree Vijaya recorded higher P uptake than the local variety. Nutrient uptake did not vary with the source of organic manure. Maximum uptake of nutrients was observed when 75 kg N ha-I was applied. Significant variation In available Nand K status of the soil after the experiment was observed only due to source of organic manure. Farmyard manure applied plots showed higher status of these nutrients compared to poultry manure and coir pith compost applied plots. Higher status of available P was observed in the soil when the improved variety was raised irrespective of the source of organic manure. Nitrogen @ 75 kg N ha-I registered higher available P content in the soil after the experiment. The study revealed that application of farmyard manure @ 12.5 t ha" or poultry manure @ 5 t ha" along with 75:50:100 kg NPK ha" resulted in higher returns from Sree Vijaya and Kariyilapothiyan, two short duration varieties of cassava, in lowlands. No variation between varieties was observed in their response to N levels as well as to the sources of organic manure. The results suggested the suitability of poultry manure as an alternative to farmyard manure for cassava cultivation in lowlands. Coir pith compost can also be used as an alternate source of organic manure provided it is made cost effective.