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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 Control of aphis craccivora koch. with fungal pathogens and their impact on the natural enemies of the pest(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1989) Hareendranath, V; KAU; Vasudevan Nair, K PStudies were made to collect information on the population fluctuation of pea aphid Aphis craccivora Koch. a regular pest of cowpea in relation to time of planting and stage of the crop. The population fluctuation of pea aphid in relation to the prevailing weather factors and the predators were also investigated to collect information on host predator interactions and interrelations. A survey on the occurrence of fungal pathogens associated with pea aphid was conducted in the pulse crops raised at the Instructional Farm, College of Agriculture, Vellayani and adjacent farmers fields. The suspected fungi were isolated and their pathogencity tested in the laboratory. Pathogencity could be proved only in the case of Fusarium pallidoroseum (Cooke) Sacc. Detailed studies were made on its growth, sporulation and pathogenicity using different artificial culture media. It was observed that the cowpea crop planted during November recorded maximum population of pea aphid followed by crop planted during October and December. Lowest population of pea aphid was noticed in the crop planted during March. The active reproductive stage of the crop recorded maximum population of pea aphids. Correlation studies with weather factors and predator population revealed that relative humidity and predator population was positively correlated with the population of pea aphid. Regression analysis of the data obtained indicated that 84 per cent of variation of population could be accounted by the variables under study. Partial regression coefficient of the aphid population and relative humidity was found to be positive and significant. Partial regression coefficient between pea aphid population and predator population was also positive and highly significant. Studies on the pathogenicity of F. pallidoroseum showed that pea aphid infected with the fungus turned pale and assumed a brownish black discolouration. Death occurred in 48 to 72 hours after infection and white mycelial growth appeared on the cadavers 24 to 48 hours after death. Growth, sporulation and virulence of the fungus was found to be superior in Sabouraud medium followed by potato dextrose agar. Sporulation was maximum in 6 day old culture and virulence was highest in 6 day and 7 day old cultures. For mass production of the fungus broken maize grain appeared to be the most suitable media followed by tapioca chips and jack seed as they produced maximum number of spores. Studies on the safety aspects of the pathogen showed that the fungus was not pathogenic to the crop plants tested viz. rice, bhindi, chillies and tomato and also to the predator Menochilus sexmaculata. Bioassay showed that LC50 of the fungus to pea aphid was 3.408 x 10 6 spores per ml. Field experiment to test the efficacy of the fungus in controlling aphid population revealed that the fungus at the rate of 7 to 10 6 spores per ml and 3.5 x 10 6 spores per ml was as effective as the insecticide quinalphos 0.05 per cent. The fungal treatment did not show any harmful effects on predator population in the field.ThesisItem Open Access Studies on the regulation of progeny production and sex-ratio of Wesmael(Department of Agricultural Entomology, College of Horticulture,Vellanikkara, 1979) Susamma, Jacob; KAU; Abraham, C CThe fecundity, progeny production, female – male composition of the progeny and duration of development of Bracon brevicornis wesmael as influenced by the density and size (weight) of host larvae of Corcvra cephalonica Stainton and the sex-ratio of the parent parasite population were studied at three temperature- humidity (TH) combinations, viz, 280c and 75% RH (TH1), 300c and 60% RH (TH2) and 320c and 50% RH (TH3). The maximum fecundity of the parasite was registered consistently at all the three TH levels at a host density level of two larvae per female parasite. The exclusive use of light weight larvae (weight range 8 to 10 mg) as hosts produced significantly less number of eggs at the TH1 and TH2 levels, while at the TH3 level the fecundity was maximum when the heavier host larvae (weight range 30 to 35 mg) were used. The parental sex-ratio levels of 2:1 and 3:1 (female:male ) led to the production of higher number of eggs than under the ratios of 1:1, 1:2 and 1:3. The maximum progeny production in B. brevicornis at the TH1 and TH2 levels was attained under a host density level of two larvae per female parasite. The progeny production was relatively higher at the TH1 and TH2 levels when heavier larvae were exposed for parasitisation. The superiority of the parental sex-ratio of 2:1 (female: male) in the production of higher number of progeny was established at the TH2 and TH3 conditions. Significant influence of the host larval density on the female progeny production was detected at the TH1 and TH2 levels. The female progeny production was maximum at a host larval density level of two per female parasite at the TH2 combination, while this was found to be the highest at a density level of one larva per female parasite at the TH1 level. Relatively heavier host larvae produced significantly higher number of female offsprings at the TH2 and TH3 combinations. The parental sex-ratio level of 2:1 (female:male) consistently produced maximum number of female progeny. The influence of host larval density on the proportion of females was pronounced only at the TH3 level and a density level of two laevae per female parasite was found to be better with reference to the production of a higher proportion of females. The sex-ratio of the parent parasite population influenced the proportion of females in the F progeny and a ratio of 1:3 (female:male) produced higher proportion of females at the TH2 and TH3 combinations. The host larval density, weight of host larvae and the sex –ratio of the parent parasite population exerted significant influence on the duration of development of B. bravicornis. The feasibility of manipulating the ambient temperature-humidity conditions for maintaining laboratory cultures of B. brevicornis at the maximum possible levels has been discussedThesisItem Open Access Effect of phorate applied for the control of bunchy top vector of banana Pentalonia nigroneroosa Coq. on the plant and in the soil environment(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1989) Sitarama Rao, D; KAU; Mohandas, NA series of experiments were carried out for ascertaining the basic problems related to the current recommendations for managing bunchytop disease of banana through the application of phorate. The absorption, translocation and metabolism of phorate applied in the soil was influenced more by the condition and age of the plant than by the dose of the insecticide. Since the application of 2.50 g ai/plant did not result in corresponding increase in the residue content or the bioefficacy in the early phases of crop growth, when compared to the 1.25 dose, the latter can be used without significant loss in efficacy. A definite dose-effect relationship existed between the phorate content of plant and the mortality of P.nigronervosa confined at feeding sites. The median lethal doses of the insecticide content of the plant tissue were higher during declining phase of absorption as compared to those obtained during the active absorption phase. The result indicated the lesser toxicity of some components in the total residue during the later phase of the crop. Application of phorate granules in leaf axils was less effective than the treatment done in the soil and hence the current recommendation to use less quantity of insecticide when applied in the leaf axils has to be altered. A simple technique for the separation, identification and quantification of phorate and its metabolites was developed. Phorate and phorate sulfoxide contents of the total residue showed inverse relationship with each other while the other metabolites did not exhibit a clear relationship among them. Phorate and phorate sulfoxide exhibited more positive direct influences on the morality of the vector than the other metabilites. The absorption and toxicity of the insecticide content in plants did not vary significantly up to 174 DAP, when applied @ 2.50 g ai/plant at different intervals after planting. Absorption was very low when the insecticide was applied at 180 and 210 DAP. For ensuring residues within tolerance limits (0.10ppm) in raw fruits, the insecticide treatment has to be limited to 150 DAP and for ripe fruits the limit can be extended up to 180 DAP. The absorption and persistence of phorate and metabolites was significantly higher in plants grown in summer season than in those grown in rainy season. The absorption of insecticide was high in sandy soils and it was lowest in black cotton soils during the active absorption phase. The insecticide persisted at effective levels for 75 days in sandy, 90 days in lateritic upland and 105 days in black cotton soil. Sulfoxidation of the thioether moiety was the dominent metabolic pathway in sandy soil while desulfuration pathway was predominent in the other three soils. Application of phorate at planting, @ 2.50 g ai/plant, did not adversely affect the soil microflora as observed at the time of harvest of the crop.ThesisItem Open Access Relative susceptibility of cashew types to infestation by the tea mosquito helopoltis antonii signoret (hemiptera:miridae)(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 1981) Thomas, K M; KAU; Abraham, C CThe relative susceptibility of fourteen cashew accessions (Anacardium occidentale L.) to infestation by the tea mosquito bug Helopeltis antonii signoret (miridae: HEmiptera ) was evaluated in the field experiments conducted at the Cashew Research Station , Madakathara during September 1979-March1980. The field damage Intensites and the extent of damage Inflicted by the insect consequent on confinement on shoots and panicles were recored on a 0-5 scale and it was found that the accessions 22,1112, 1430 and 1097 were least susceptible with regard to the intensity of natural field infestation of the vegetative shoots. Regarding the intensity of field infestation on floral branches, the accessions, 22, 1112,1352,1469 and 1097 were significantly less susceptible than the other types . With reference to the intensity of damage to vegetative shoots under confinement none of the accessions was found to be promising . The accession numbers 1219 , 1469 and 1431 were found to be least susceptible to H. antonii infestation under confinement on floral branches . Since the damage to the floral branches, particularly under confinement , Is relatively more important factor responsible for yield reduction these trees can be identified to be relatively more promising . The influence of certain biochemical factors (total nitrogen , soluable sugar and tannins ) on pest infestation in shoots and floral branches was ascertained by working out simple correlation coefficients. The only significant association detected was between the tannin content in the vegetative shoots on the one hand and the pest infestation intensities under confinement , on the other. The shade intensities within the canopies had no the extent of susceptibility to the pest. The tree architecture patterns were found to be of two basic types, namely, extensively branching (spreading ) and intensively branching (bushy ). Variations in the canopy configuration did not influence the susceptibility trends. The inconsistencies in the relative susceptibility of different accession with reference to shoot and panicle damage intensities have been discussed.ThesisItem Open Access Plant parasitic nematodes associated with pineapple in Kerala(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 1981) Hamza Koya, C P; KAU; Venkitesan, T SAs a part of the studies on the occurrence of plant parasitic nematodes associated with pineapple in Kerala, a survey was carried out in different agro climatic regions of the Kerala State and it was found that R. reniformis occurred in more than 76 per cent of the locations sampled. Helicotylenchus spp. were recorded in about 50 per cent of the locations. The other plant parasitic nematodes detected in association with the crop included Meloidogyne spp., Creconemoides spp., Pratylenchus spp., Hoplolaimus and Hemicyclophora occurred in very low population densities. A new species of Helicotylenchus closely resembling H. digitatus ( Hussain and Siddique, 1964) but differing with respect to spear knob characters and location of excretory pore has been reported to be associated with the crop. The pot culture trial with M. incognita indicated that this nematode could not induce pathogenic effect on the cv kew even at the highest inoculum levels of 10,000 larvae per 7.5 kg soil during the period of 180 days.ThesisItem Open Access Studies on the extent of damages caused by pests of stored copra and controle of the important pests(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1989) Nalina kumari, T; KAU; Mammen, K VThe magnitude and intensity of insect pest attack in stored copra, in the Southern Districts of Kerala, were assessed in an elaborate survey, adopting a random sampling technique for two years. The survey revealed that insects cause significant damage even in well preserved good quality copra stocked for more than five months. N. rufipes, O. surinamensis, A. advena and L. serricorne were the major pests recorded. The immature stages of N. rufipes, adults and immature stages of the other pests were seen inside the tunnels made between the endosperm and testa. N. rufipes and O. surinamensis were distributed widely, while the predominant insects observed at Nedumangad were A. advena and L. serricorne. All the insects were found breeding on copra from June to October. A positive correlation between moisture content of copra and the insect incidence was observed in the studies. The influence of A. flavus on the extent of damage caused by these pests showed that the presence of the mould was not a predisposing factor for insect attack. The extent of damage in copra due to the infestation by N. rufipes was 12.2 per cent at the end of sixth month whereas O. surinamensis caused only three per cent damage. When combind with fungus, the damage caused by N. rufipes was reduced by 50 per cent. This effect was not observed on O. surinamensis. The infection by the fungus adversely affected the oil content of copra and this effect was not altered by the preceeding or succeeding infestation of the insect. The insect attack alone caused significant reduction in oil yield of copra during the sixth month after exposure only. The quality of oil was adversely affected when infested by insects and fungus independently. The infestation of insects preceeding or succeeding fungal infection did not alter the adverse effect caused by them independently. The quantitative loss caused by the attack of N. rufipes and O. surinamensis to copra obtained from different varieties of coconut did not show significant variations. Among the different varieties tested LM and LO were more favourable to N. rufipes and DxT and TxD to O. surinamensis. Two to six fold increase in the longevity of the adults of N. rufipes was observed when they were provided with immature stages in addition to copra for feeding. N. rufipes and O. surinamensis caused significantly greater damage to copra under eight per cent and six per cent moisture levels respectively. The development of N. rufipes was totally arrested in copra with four per cent moisture content. The development of immature stages and adult population of N. rufipes were higher in copra containing eight per cent moisture level and those of O. surinamensis in copra containing six per cent moisture. The response to moisture fluctuations was more conspicuously seen in O. surinamensis than in N. rufipes. Though the population of insects were found to be high in reused gunny bag followed by heap storage, the extent of damage was higher in heap storage than in reused gunny bags. High populations of N. rufipes and O. surinamensis were recorded from heap and reused gunny bags respectively. Low populations of insects were recorded in copra stocked in polythene/alkathene lined gunny bags and netted polythene bags. But the oil extracted from copra stored in these types of bags gave significantly higher acid values. In the trials done to find out a safe prophylactic method of control against pests of copra, malathion and phoxim proved more toxic to N. rufipes and malathion and fenitrothion to O. surinamensis. When these insecticides were evaluated for their persistence on gunny bags, malathion 0.4 per cent gave protection up to five months and fenitrothion 0.8 per cent up to six months. The residues of malathion and fenitrothion came below tolerance limits, 15 and 60 days after treatment respectively . For complete control of the major pests of copra 4.5 g/m (2.5 g ai/m ) of aluminium phosphate with one day exposure period was found adequate. The residue of phosphine in the copra fumigated as above was below tolerance limit.ThesisItem Open Access Resurgens of brown planthopper Nilaparvata Lugens (stal) on rice treated with various insectisides(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1989) Thomas biju, Mathew; KAU; Mohan das, NA series of green house experiments were carried out for screening the insecticides, fungicides and herbicides recommended for the control of pests, diseases and weeds infesting rice in Kerala, for their resurgence inducement in N. lugens. Among the thirteen insecticides screened, each at three doses and applied at three critical growth stages of the crop as well as at their possible combinations, methyl parathion, deltamethrin, fenitrothion, fenthion, quinalphos and carbaryl were identified as resurgence inducing insecticides with no apparent differences among themselves in the intensity of resurgence caused, HCH, dimethoate, monocrotophos, phosphamidon, phorate, BPMC and carbofuran were found to be free from resurgence inducement and some of them even exerted a significant suppressing effect on the progeny production of N. lugens. There was no carry over of resurgence effect over generations. The results of the experiments also revealed that: 1. The manifestation of resurgence inducing property of insecticides was more at the higher doses than at the field doses or lower doses. 2. The frequency of occurrence of resurgence among the different treatments with resurgence inducing insecticides showed that a single application at any of the three critical growth stages of rice and two applications combining any two of the three growth stages were on par while three consecutive treatments covering all the three growth stages was more favourable for manifestation of resurgence. 3. The growth stages of the host plant had significant influence on the manifestation of resurgence inducement of insecticides. It varied with the properties of insecticides used. Some manifested resurgence at tillering, some at panicle initiation and none at booting stage. 4. The resurgence effect induced by the insecticides was found to last in the treated plants for a period of 15 to 20 days after treatment and the results indicated, that there was no cumulative effect by repeated treatments on insect populations. In the light of the above findings the method of screening resurgence inducing insecticides in the green house was standardized as the application of the insecticide at doses higher than the field doses thrice covering the tillering, panicle initiation and booting stages preceeding the exposure of insects for assessment of progeny production which may be done at 15 days after the third application. In further screening adopting the procedure standardized above malathion, methyl demeton, FMC 35001, fenvalerate, permethrin and cypermethrin were found inducing resurgence in N. lugens. The granular insecticides were screened giving two treatments (tillering + panicle initiation) and exposing insects at 30 DAT for egg laying. Results revealed that diazinon, phorate, cartap and carbofuran caused resurgence of N. lugens. Endosulfan, formothion, phosalone, methamidophos, chlorophyriphos, DDVP and their combinations with HCH or carbaryl (liquid formulations), aldicarb, quinalphos and sevidol (granular) were free of resurgence hazard. At the recommended doses and methods of application of fungicides zineb, mancozb, captafol, ediphenphos, kitazin, carbendazim and carboxin and the herbicides 2, 4-D (sodium salt and ester), pendimethalin, fluchloralin, butachlor, propanil and thiobencarb did not post any resurgence problem. The inducement of resurgence by insecticide was seen significantly influenced by the variety of host plants of the insects involved. The levels of plant mediated resurgence inducement and resistance of the plants to insect attack were not mutually related. In screening insecticides for the control of a pest in an agroecosystem, the interaction of the popular varieties of the crop available in the area with resurgence inducement also should be studied. The resurgence inducing mechanism of six identified insecticides was studied in detail. The results of a series of green house and laboratory experiments revealed that : 1. Resurgence inducing insecticides brought about some morphological changes in the crop causing some improvements in the stand but the magnitude of the changes were not adequate to influence the attraction of the insects or build up of the pest population. 2. The application of the insecticides caused significant variations in the nutrient content and biochemical constituents of treated plants causing consistent changes in the total nitrogen, free sugars and free amino acid contents. 3. The feeding of N. lugens on treated plants was significantly higher as indicated by the feeding indices. 4. The correlation studies and path coefficient analysis of the data relating to the magnitude of changes in the above factors caused by the application of insecticides could be attributed as the major cause of plant-mediated resurgence inducement. The direct application of resurgence inducing insecticides revealed that some of the insecticides which showed plant mediated resurgence (methyl parathion, deltamethrin and carbaryl) had direct stimulating effect also on the progeny production of N. lugens at sublethal doses while some (fenthion and fenitrothion) did not show any increase in progeny production and some (quinalphos) showed only marginal effect. While carbaryl and methyl parathion were more stimulatory at lower levels, deltamethrin stimulated reproduction at both the lower and higher levels. The field experiment revealed that the resurgence observed in the field was the added effect of plant-mediated resurgence observed in green house experiments and the direct effect of the pesticides caused by their sublethal doses. In general the conclusions from the green house experiments were in agreement with the results obtained from the field. It was seen that the changes in predatory population in field caused by the application of pesticides did not contribute significantly to the inducement of resurgence in N. lugens. It was also observed that the assessment of plant induced resurgence of insecticides in green house experiments and the direct effects of the toxicants on the insects will serve as an effective alternative elaborate field experiments for evaluating the resurgence effect of insecticides.ThesisItem Open Access Bioecology and control of pests of rose(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1989) Vijayan Nair, V; KAU; Visalakshy, AThe distribution of the major insect and mite pests of rose in Trivandrum taluk and the damages caused by them were studied in a survey . The survey was conducted in six locations in the taluk (Kowdiar, Paruthippara, Karamana, Palkulangara, Vanchiyoor and Vellayani) at monthly intervals for a period of 13 months starting from August 1986, adopting standard sampling techniques . The results of the survey revealed that the major pests of rose in the area were the thrips, R. Syriacus, S. dorsalis, the scale A. aurantii, the leaf feeding beetles Adoretus spp and the mites, T. neocaledonicus and T.cinnabarinus. The mean levels of population /damage found during the period of the survey showed that T.neocaledonicus was the most important pest in all the locations and it caused more than 50 percent of the plants damaged in some locations. It was followed by Adoretus spp, A. aurantii, R. syriacus, S.dorsalis and T.cinnabarinus in a descending order of importance with apparent variations in pest status at different locations. An overall assessment of the seasonal incidence of the pests revealed that the thrips and mites were seen in serious proportions during the months of December to May and the beetles caused heavier damage from November to January whereas the scale insect was seen damaging the plants throughout the year. Between the population of thrips and mites and maximum temperature there was significant positive association. While the relative humidity and number of rainy days showed significant negative correlation. Rainfall also had significant negative correlation with the thrips and mites, but it was statistically insignificant in the case of T.cinnabarinus only. The nature of damage caused by various pests of rose was studied in detail. It was seen that the thrips, mites and the scales were causing serious damage to leaves causing its drying and withering. The other sucking pests and the defoliators noted were of minor importance except the leaf beetles Adoretus spp which was found to cause serious defoliation of the of the plants. The investigation on the biology of R.syriacus on the rose showed that the life cycle was completed in 16.9days. When they were reared on castor and subabul the duration and size of various stages were same as those of rose while those reared on cassava were bigger in size and the life cycle was shorter. The experiments on chemical control of pests of rose showed that monocrotophos, dimethoate or fenthion at 0.05percent spray was effective in controlling the different spices of pests . But in the case of flower bud damage caused by S.dorsalis, a higher concentration of 0.1 per cent of the insecticides was necessary for getting proper control.ThesisItem Open Access Pest complex associated with mango inflorescence and their control(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 1984) Satheesan, N V; KAU; Abraham, C CIn a survey conducted during 1982-83 in the State of Kerala to study the incidence of various insect pests associated with mango inflorescence with reference to their seasonal history, a total of ten insect pests were recorded. The hoppers idioscopus niveosparaus Leth. and I. clypealis Leth. were found to be widely distributed in the State. Significant variability was not detected among the population loads of I. niveosparsus in different districts, while in the case of I. clypealis such variations were significant. The heaviest populations of the latter was recorded from the Calicut District. The seasonal changes in I. clypealis populations were recorded only in the two Districts of Calicut and Trivandrum. I. niveosparsus showed a well defined peaks in the Palghat and Wynad districts. The fluctuations I. niveosparsus and I. clypealis populations have been discussed with reference environmental conditions. Procystiphora mangiferae Felt. is reported for the first time from the State from the Wynad and Cannanore Districts. Infestations by the pest led to transformation of the floral buds to conical galls. In the Wynad District, there was a well defind population peak in March, while in the Cannanore District a district crest waslacking. The mango blister midge, Erosomyia indica grover and Prasad was recorded to occur in association with P. mangiferae in these two districts. The larvae of E. indica tunnel into inflorescence axis and cause ovate galls thereby causing losses. Bombotelia jocosatrix Gn. was recorded from the Cannanore, Palghat, Trichur and Alleppey Districts throughout the flowering season. Eublemma anguilifera Moore as well as another unidentified spp. of Eublemma were recorded to occur throughout the State, except in the wynad District. The seasonal fluctuations of this pest were significant only in the Palghat District. An unidentified species of Cacoecia was recorded for the first time as a minor pest of mango inflorescence. The larvae fed on flowers and floral buds. The other pests observed during the course of the survey were Rapala manea Hewitson, Haplothrips ganglbaueri Schmutz, Dichocrosis punctiferalis Guenee and an unidentified Geometrid. The bio-efficiency of monocrotophos applied by two methods, namely, stem injection and stem banding, against the Idiocerine hoppers infesting mango inflorescence was evaluated in a separate experiment. The relative toxicity of the insecticide was determined from the time- mortality relationship between the insecticide reaching the inflorescence of treated trees and the mortality of the fourth instar nymphs of I. niveosparsus. The LT -50 values of the nymphs following application of the insecticides by the stem injection method was found to be substantially lower than the corresponding values for the stem banding method of application. It was thus evident that the toxicant moved at a faster pace when administered by the stem injection method. The variations in the pattern of translocation of the toxicant under the two methods of administration have been discussed. The residues of monocrotophos on freshly formed mango fruit at five weeks after application by the stem injection method at 4 ml and 2 ml ai/tree were 0.3600 ppm and o.3750 ppm respectively. The corresponding residues in the mango fruit consequent on stem banding method of administration were 0.0550 ppm. The implications of the above results in formulating control methods against Idiocerine hoppers infesting mango inflorescence have been discussed.
