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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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2003 - 20072
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Subject: Agricultural Entomology × Author: Karthikeyan, K × End date: 2007 × Type: Thesis ×
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    ThesisItemOpen Access
    Bio efficacy of newer isecticides against leaf hopper, empoasca motti pruthi in bitter gourd
    (Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2003) Karthikeyan, K; KAU; Mani, Chellappan
    Bio efficacy of newer insecticides was evaluated by two field experiments at the College of Horticulture, Vellanikkara during rabi, 2001 and summer, 2002.against major pests of bitter gourd. Imidacloprid (2 g a.i.kg") and acetamiprid (1.5 g a.i.kg") were used as a seed dressers .The newer molecules namely acetamiprid, ethofenprox and imidacloprid were sprayed at different crop stages viz., early vegetative (30 DAS), pre flowering (50 DAS) and fruiting stage (64 DAS) as separate treatments. Acephate was used as a standard check. The present investigation revealed that acetamiprid (1.5 g a. i. kg") was the most effective insecticide as seed dressers against sap feeders viz., leaf hoppers and aphids. Foliar spray application revealed that both imidacloprid (20 g a.i.ha") and acetamiprid (10 g a.i. ha") consistently effective in reducing the sucking pests viz., leaf hopper and aphids followed by ethofenprox (50 g a.i.ha") in both the season. Fruiting stage spray by acetamiprid and imidacloprid had registered the lowest fruitfly infestation .The fruit borer infestation was less in the plots, which received the preflowering and fruiting stage insecticide sprays. The highest yield of bitter gourd was recorded in the imidacloprid (pre flowering stage spray) treated plots in both rabi (1 o 1. 66'fruits/Sm2) and summer (1 02. 66fruits/Sm2) seasons. Seed treatment of newer insecticides had no harmful effect 'on soil micro flora (fungi, bacteria and actinomycetes). Population of natural enemies was unaffected by the insecticide applied along with the seed compared to the foliar applications. Studies on the residues of imidacloprid by high performance liquid chromatography indicated that imidacloprid applied at different stage of the crop viz., sowing, early vegetative, preflowering and fruiting stage to bitter gourd resulted no detectable residue in the harvested fruits.
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    ThesisItemOpen Access
    Bioecology, population dynamics and integrated management of rice blue beetle, Leptispa pygmaea Baly (Chrysomelidae:Coleoptera)
    (Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2007) Karthikeyan, K; KAU; Sosamma Jacob
    The Rice Blue Beetle Leptispa pygmaea Baly (Chrysomelidae : Coleoptera), hitherto reported as a minor pest of rice, has recently assumed a serious status by causing severe outbreaks in different northern districts viz., Palakkad, Kannur and Kasaragod of Kerala.This pest is reported to inflict extensive damage to rice in both kharif and rabi seasons. Since the rice blue beetle has been considered as a pest of minor importance, very scanty information is available on the pest. In this context, the present investigation on the “Bioecology, population dynamics and integrated management of Rice Blue Beetle Leptispa pygmaea Baly” was carried out at the Regional Agricultural Research Station, Pattambi, Kerala Agricultural University during 2004-06. The study has helped to generate information on the biology, population dynamics and management methods of rice blue beetle by which an IPM strategy could be formulated against this pest. The biology of rice blue beetle, L. pygmaea was worked out on a short duration (Jyothi) and a medium duration (Aiswarya) variety of rice under nethouse conditions. The female beetle laid eggs either singly or in groups in a straight line either on the dorsal or ventral surface of mature or tender rice leaves of Jyothi and Aiswarya. There was no marked difference in the biology of the blue beetle between the two rice varieties. Eggs were seen glued to the leaf surface. The fecundity ranged from 10 to19 eggs during an oviposition period of six days. A pre oviposition period of 14 to 16 hours was also observed. The eggs hatched into grubs within 3 to 4 days. The grub period lasted for 6 to 11 days with five instars, each with duration of 1 to 2 days. The grub pupated for 2 to 4 days and the adult beetle emerged out. The total life cycle from egg to adult stage was completed within 12 to 19 days. The longevity of adult varied with the sex of blue beetle. Males lived longer than females. The male life span was 37 to 41 days, while the females lived for 25 days. Among the duration of different stages viz., egg, larva, pupa and adult of L. pygmaea, the period of adult stage was found to be longest (39 days) followed by larva (8 days), egg (3 days) and pupa (3 days). The emergence of adult beetle was highest during morning period between 0800 to 0900 hours and then it was reduced as the day temperature increased. No emergence was observed between 1300 and 1500 hours when the temperature was high at the noon. The number of male beetles in the field was more, compared to the females with a sex ratio of 1.5: 1.3. Study on the morphology and morphometrics of different stages of blue beetle showed that the size of egg measured 0.39 mm in length and 0.19 mm in width. Freshly laid eggs were light green and changed to yellow towards hatching. The grub was light green in colour with brown head. It showed a small head capsule, long body and a tail like projection at the posterior end of the body. The newly emerged first instar grub was light green coloured with a brown head and changed to dirty white towards pupation. The head capsule measured a width of 0.17 to 0.26 mm from 1st to 5th instar, while the body measured an average length and width of 4.56 and 0.90 mm respectively. The tail length increased from 0.1 to 0.2 mm from first to fifth instar. Freshly formed pupa was white in colour and later it changed to brown and was seen loosely attached to the leaf by its distal end. It measured a maximum length of 3.89 mm and minimum length of 3.73 mm. Newly emerged adult beetle was metallic bluish green in colour dorsally and white coloured on the ventral side of the body. The male and female beeles could be differentiated based on the body size. The males were bigger in size than the females. The male had a longer antenna (1.1mm) than the female (0.08mm).The basal two segments were larger than the rest. In case of females, the basal scape was the largest (truncated) with 0.15 mm in width. In both sexes, the 3rd, 4th, 5th and 6th antennal segments were small and uniform, while the 7th to 11th segments were larger than the middle four segments. Dissection of the reproductive systems revealed that male reproductive system consisted of tegmen and sipho. The aedeagus showed an average length of 1.36 mm and width of 0.09mm. The female reproductive system consisted of spermatheca and two lateral coxites with an average length of 1.60 mm and width of 0.52 mm. Survey on the field population dynamics of blue beetle during Kharif and Rabi, 2005 showed that in Kharif’05, the field incidence of L. pygmaea started from fourth week of June at 10 days after transplanting and there was an increasing trend in the population up to the second week of July’05. The peak population was found coincided with the early tillering stage of the crop. After the second week of July’05, there was a declining trend in the population and reached the lowest during the third week of September’05. The field population of blue beetle was highest during the month of July in Kharif season. The abiotic factors viz., maximum temperature, minimum temperature, relative humidity, rainfall and sunshine during the peak period were 29.8C, 23.7C, 95 %, 50.9 mm and 2.9 hours respectively. In Rabi’05, the beetle population showed an increasing trend from the third week of October at 10 days after transplanting and reached a peak during the first week of November’05, when the crop was in the tillering stage. The population indicated a decreasing trend from the second week of November onwards. Highest population occurred at 24 DAT when the crop was in the early tillering stage during both seasons (Kharif and Rabi). Therefore, stage of the crop is a critical factor for the rapid build up of L. pygmaea. The weather parameters during the peak period were maximum temperature 31.8 C, minimum temperature 23.2 C, relative humidity 95 %, rainfall 70.2 mm and sunshine 4.2 hours. Two abiotic factors viz., minimum temperature of 23 C and relative humidity of 95 % were found to influence the peak population in both the Kharif and Rabi seasons. Correlation analysis of beetle population and per cent leaf damage with the weather parameters revealed a negative correlation with regard to maximum temperature and sunshine hours (respective correlation values -0.281 and -0.400). A positive correlation of blue beetle population with minimum temperature and relative humidity was observed. Rainfall showed no significant effect on beetle population. Damaged leaves by L. pygmaea were found to be positively correlated with minimum temperature and relative humidity while it was negatively correlated with maximum temperature and sunshine hours. However, there was no significant relationship between rainfall and per cent damaged leaves. Thus, it is indicated that minimum temperature and relative humidity were the two important abiotic factors that influence the damage by L. pygmaea. Study on the nature of attack and symptoms of damage of L. pygmaea showed that both the grub and adult feed on the upper surface of rice leaves by scrapping chlorophyll tissueleading to longitudinal white streaks on them. The streaks made by the larvae were shorter and narrower than those by the adults. In case of severe damage, the rice leaves were seen folded longitudinally and ultimately dried up. The plants became very weak or dried up. From a distance, the damaged rice patch showed severe drying. Symptoms of damage by rice blue beetle resembled those caused by leaffolder. Observations on the feeding intensity of different stages of the blue beetle revealed that grubs caused highest damage followed by adult female and adult male in both Jyothi and Aiswarya. The grub caused 69.0-73.7 per cent more damage than males while female caused 48-59 per cent more damage than males. The study on leaf area consumption by different stages also indicated similar results. Leaf area consumption by L. pygmaea was more in Jyothi than in Aiswarya. Early tillering stage was found to be the most susceptible stage for the infestation of blue beetle in both Kharif and Rabi . Damage was found to increase from the seedling stage and reached peak at early tillering and thereafter it gradually declined. The order of susceptibility of growth stages to rice blue beetle damage was early tillering > seedling > maximum tillering > panicle initiation > booting > flowering. Transplanted rice suffered more damage by L. pygmaea than the direct seeded rice in both the rice varieties Jyothi and Aiswarya during Kharif and Rabi’05 seasons. In Kharif the transplanted rice suffered 42.40-83.15 per cent more damage over direct seeding in Jyothi during seedling stage. In early tillering stage, the transplanted rice suffered 34.24 to 58.17 per cent more damage over direct seeding. Studies were also carried out on integrated pest management methods involving screening of resistant lines / varieties, effect of plant spacing and oil cakes, chemical management by nursery treatment with granular insecticides and main field treatment with eco-friendly foliar insecticides against L. pygmaea. Among the 106 varieties / entries screened for their field reaction against L. pygmaea, none of them was found to be completely resistant. No high yielding variety except Hraswa (a short duration Mannuthy variety) showed moderate resistance. But nine traditional Pattambi varieties viz., Ptb.3, Ptb.4, Ptb.7, Ptb.9, Ptb.18, Ptb.19, Ptb.20, Ptb.25, Ptb.26 revealed a damage score of ‘3’ indicating moderate resistance. Therefore, these varieties could be utilized for future breeding programmes for resistance against rice blue beetle. Other KAU varieties showed susceptibility, while three varieties viz., Jyothi (Ptb.39), Rangini (MO10) and Bharathy (Ptb.4) were found to be highly susceptible to L. pygmaea. The most popular rice variety of Kerala, Jyothi,was found to be highly susceptible to rice blue beetle. Search for the alternative hosts for L. pygmaea revealed that among the 10 commonly seen weed plants in rice fields, the beetle was found to oviposit only on two grassy weeds viz., Panicum repens and Isachne miliacea. Though eggs were laid, there was no hatching of eggs on I. miliacea. But on P. repens, the beetle laid 12-15 eggs with cent per cent hatchability and the beetle was able to carry out its normal life cycle on this weed host in 10-13 days. A comparative study on the biology of L. pygmaea on Jyothi, Aiswarya and Panicum repens indicated that the life cycle of rice blue beetle was shortest (11.5 days) on P. repens followed by Aiswarya (14 days) and Jyothi (15 days). The influence of agronomic practice of different spacings on the incidence of L. pygmaea revealed that in closer plant spacings (10x15 cm and 10 x 10 cm), there was reduction on the incidence of blue beetle with reduced leaf damage, hill damage and beetle population. Infestation was significantly higher in the recommended wider spacing (20x15 cm), as compared to closer spacing. The effect of application of neem cake, castor cake and pungam cake in the field against L. pygmaea showed that there was no significant difference between these cakes on the leaf damage, damaged hills and beetle population. No interaction effect of plant spacings and oil cakes was observed. Survey for the natural enemies of blue beetle in the field showed that the beetle eggs were parasitized by Trichogramma sp., Telenomus sp. and Tetrastichus sp. indicating a good scope for biological control of the pest. Laboratory studies to assess the pathogenicity of white muscardine fungus, Beauveria bassiana against L. pygmaea illustrated the effective role of B. bassiana by causing a cumulative mortality of 56.67 to 80.00 per cent at 105 to 109 spores / ml. Its LC50 value was 2.26 x 104 spores / ml. Evaluation of the entomopathogenic nematode (EPN), Heterorhabditis indica under the laboratory conditions indicated its bioefficacy by bringing out mortality against grubs of L. pygmaea. The EPN produced a cumulative mortality of 66.67 to 91.67 per cent at concentrations of 5 IJ’s to 9 IJ’s in the grubs with a LC50 value of 3.83 IJ’s per ml. Biological management studies thus resulted in the identification of three new egg parasitoids in the field. The pathogenicity of white muscardine fungus and the EPN against L. pygmaea were also explored. Studies on the chemical management of L. pygmaea by nursery application of granular insecticides revealed the efficacy of cartap hydrochloride in reducing the leaf damage, hill damage and beetle population of L. pygmaea in both Kharif and Rabi seasons during 2004 and 2005.The leaf damage was reduced by 40.29 and 37.86 per cent (mean = 39.21 per cent) over control during 2004 and 2005 respectively while the beetle population was reduced by 30.73 and 61.13 per cent (mean = 45.9 per cent). Hill damage was reduced by 55.16 and 33.71 per cent (mean = 44.4 per cent) over control during the years. Carbofuran was the next best effective insecticide against L. pygmaea. It produced significant reduction of leaf damage by 30.16 and 23.62 per cent (mean = 26.9 per cent) over control in Kharif and Rabi respectively. Beetle population was reduced by 25.10 and 54.66 per cent (mean = 39.9 per cent) and hill damage by 55.70 and 10.11 per cent (mean = 32.9 per cent) over control. Fipronil was found least effective against L. pygmaea. Persistent toxicity of granular insecticides applied in the nursery against blue beetle showed that carbofuran was the most persistent insecticide with highest PT value followed by carbosulfan, phosphamidon, cartap hydrochloride and fipronil. Evaluation of eco-friendly foliar insecticides for the field toxicity against L. pygmaea indicated the effectiveness of B. bassiana at 107spores/ml. It significantly reduced leaf damage (mean = 46.7 per cent), population of blue beetle (mean = 47.7 per cent), and hill damage (45.9 per cent) over control. The insecticide, chlorpyriphos @ 0.05 % was equally effective against rice blue beetle. It was followed by carbaryl > econeem > paraffin oil > neem oil. The persistent toxicity of foliar insecticides in the field was in the descending order viz., carbaryl > chlorpyriphos > econeem > neem oil > paraffin oil > B. bassiana. It is quite evident that the persistent toxicity of eco-friendly insecticides is low as compared to the chemical insecticides. Though. B. bassiana showed lowest persistence in the field, it was on par with chlorpyriphos in bioefficacy causing highest mortality of blue beetle.