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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 Development of F1 hybrids in okra [Abelmoschus esculentus L. Moench](Department of Plant Breeding & Genetics, College of Agriculture,Padannakkad, 2019) Jaseera, U A; KAU; Raji Vasudevan, NamboodiriThe project entitled “Development of F1 hybrids in okra [Abelmoschus esculentus L .Moench]” was carried out at the Instructional farm, College of Agriculture, Padannakkad during April-July 2019 to study heterosis and combining ability. The experiment was carried out in two parts. In part I, six diverse parents viz. AE5, AE16, AE18, AE20, AE30 and Salkeerthi were raised in a crossing block. They were crossed in half diallel fashion and 15 F1 hybrids were produced. In part II, the hybrids were evaluated along with their parents and checks in a randomized block design with 26 genotypes and three replications. Arka Anamika and Salkeerthi were used as OPV checks and Manjima and Arka Nikita as F1 hybrid checks. Parents of Manjima viz. Gowreesapattam local and IC282257 were also included as checks. Half diallel analysis was adopted for combining ability analysis. Relative heterosis, heterobeltiosis and standard heterosis using F1 hybrid Arka Nikita as standard check were worked out for all the characters. The estimation of heterosis revealed significant standard heterosis in the hybrids in desirable direction for growth, earliness and fruit traits. Three hybrids AE30 x AE18, AE30 x Salkeerthi and AE20 x AE30 showed highly significant positive standard heterosis for plant height. Three hybrids AE30 x Salkeerthi, AE30 x AE5 and AE18 x Salkeerthi showed highly significant positive standard heterosis for primary branches per plant. Two hybrids AE16 x AE5 and AE18 x AE5 showed highly significant negative standard heterosis for internode length. Two hybridsAE16 x Salkeerthi and AE20 x Salkeerthi showed highly significant negative standard heterosis for days to flowering. One hybrid AE18 x AE5 showed highly significant negative standard heterosis for days to 50% flowering. Five hybrids AE16 x AE30, AE16 x AE18, AE16 x AE5, AE20 x AE18, and AE30 x AE18 showed highly significant negative standard heterosis for node of fruit set. None of the hybrids showed significant positive standard heterosis for number of fruiting nodes. For fruit length AE20 x AE18 and AE20 x Salkeerthi showed significant positive standard heterosis. Three hybrids AE16 x AE30 AE5 x Salkeerthi and AE30 x AE5 showed significant positive standard heterosis for fruit girth. For fruit weight the hybrids AE30 xAE5, AE18 x AE5, AE20 x Salkeerthi, and AE20 x AE18 showed significant positive standard heterosis. None of the crosses showed significant positive standard heterosis for number of fruits per plant, marketable fruits per plant, marketable fruits per plant and yield per plant. The hybrid AE30 x Salkeerthi showed significant positive standard heterosis for mucilage content. Analysis of variance for combining ability revealed significant difference among the genotypes for all traits except fiber content, indicating sufficient variability for selection. The gca variance/ sca variance ratio indicated preponderance of non-additive gene action for all traits. None of the cross combinations exhibited high significant combining ability effects in desirable direction for all characters studied. The association of sca effects of outstanding crosses with gca effects of parents for each of the characters revealed that the high specific combiners involved high x high, high x low and low x low general combiners as parents. A combination of mean performance and gca effect was used to identify best parents and it revealed AE16, AE30 and AE20 as better performing parents for maximum number of characters. Even though the mean performance of AE16 was higher for fruit weight, number of fruiting nodes, yield per plant and marketable yield per plant, it was a poor general combiner for characters viz. number of fruiting nodes, fruit weight, and yield per plant compared to AE20 and marketable yield per plant compared to AE30. High gca effects for fruit yield in AE20 and AE30 were associated with good gca effects for number of fruits per plant and fruit weight. The parental lines AE20 and AE30 performed well even they were affected by yellow vein mosaic disease and fruit and shoot borer. Hence they can be used in further breeding program for higher yield. The parental line AE20 was the high general combiner for all of the three earliness attributes such as days to first flowering, days to 50% flowering, and node of fruit set, indicating its potential for exploiting earliness in okra. Promising crosses were identified based on mean performance, sca effect and standard heterosis for important growth and yield characters. None of the hybrids exhibited significant standard heterosis in the desirable direction for yield. Hence the hybrids showing lower value of negative standard heterosis were selected. The four better performing crosses identified were AE30 x AE5, AE20 x AE5, AE20 x Salkeerthi and AE30 x Salkeerthi. All these four crosses were good performers for marketable yield even when they were affected by yellow vein mosaic disease and shoot and fruit borer. In addition, these crosses showed good performance for few other yield contributing characters also. The cross AE30 x AE5 performed well for fruit weight, number of fruiting nodes and yield per plant. The cross AE20 x AE5 showed good performance for number of fruits per plant, marketable fruits per plant and yield per plant. AE20 x Salkeerthi was a good performer for fruit weight and fruit length. AE30 x Salkeerthi was good performer for plant height, primary branches per plant, internode length and mucilage content.ThesisItem Open Access Genetic analysis of yield and quality in fodder cowpea (Vigna unguiculata (L.) Walp)(Department of Plant Breeding & Genetics, College of Agriculture,Vellayani, 2019) Praveena, V S; KAU; Mareen AbrahamIn the present study, "genetic analysis of yield and quality in fodder cowpea {Vigna unguiculata (L.) Walp)", evaluation of different fodder cowpea accessions were done to assess the variability in the available population to identify the good performers for forage yield and quality. Based on the morphological and molecular characterization superior parents were selected for crop improvement through hybridization to develop superior cross combinations. The salient features of the study are discussed below. Significant variation was observed for all tlie fourteen characters studied, the range of mean values observed refers to the phenotypic and genotypic variability present in the base population. High genotypic and phenotypic coefficient of variation was observed for number of primary branches plant ', number of leaves plant ', leaf area index, green fodder yield plant ', dry matter yield plant"', leaf fresh weight plant"', stem fresh weight plant"', leaf dry weight plant"', stem dry weight plant"' and crude fiber content. High heritability and genetic advance for crude fiber content, crude protein content, leaf area index, leaf dry weight plant ', dry matter yield plant"', stem dry weight plant"', number of leaves plant"', stem dry weight plant'', number of leaves plant"', stem fresh weight plant"', leaf fresh weight plant*' and green fodder yield plant"'. Green fodder yield and dry matter yield had significant positive phenotypic and genotypic correlation with leaf fresh weight plant"', followed by stem fresh weight plant"', stem dry weight plant"', dry matter yield plant"', leaf dry matter plant"', number of primary branches plant"' and number of leaves plant"'. The thirty fodder cowpea genotypes were grouped into eleven clusters. Maximum contribution to divergence was shown by leaf fresh weight plant"' followed by crude fibre content, stem dry weight plant"', leaf area index, dry matter yield plant*', number of leaves plant"', crude protein content and green fodder yield plant"'. Selection index was hi^est for IT-37154999-38 and least for IC- 202804. The genotypes were ranked for characters green fodder yield, crude protein content, crude fibre content and selection index. Based on this and maximum inter cluster distance eight genotypes CO-8, MFC-09-1, IC-1061, IC- 39916, IC-97767, lC-38956-1, 17-37154999-38 and Pant Lobia-2 were selected for further hybridization programmes. Molecular characterization revealed two clusters (I and II) with 0.34 per cent similarity. The statistical cluster diagram from value and dendrogram from molecular characterization were not similar. But the eight parents selected had considerable difference in dendrogram with minimum difference between parents IT-38956-1 and IT-37154999-38. Diallel analysis is one of the techniques used to find the genetic makeup. Gca variance was greater than sea variance, for all characters except for days to first flowering and crude protein content, indicating predominance of additive gene action for most of the characters. Days to first flowering and crude protein content had non-additive gene action. Presence of heterosis also shows the ability of the parents to combine well in a hybridization programme. Superior expression of Fi may be due to fixable (additive) type of gene action and non-additive type of gene action. Thus combining ability and heterosis helps in identifying desirable cross combinations. Twenty eight hybrids from eight parent were evaluated for combining ability in diallel mating design without reciprocals. Relative heterosis and heterobeltiosis were calculated for different traits. Gca variance was greater than sea variance, indicating predominance of additive gene action. P4, Ps and Pe were good general combiners among eight parents for plant height. Gca variance was greater than sea variance, indicating predominance of additive gene action in green fodder yield and dry matter jdeld. Ps, Pe, P? and Ps were good general combiners for green foddra* yield, dry matter yield, leaf fresh weight, stem fresh weight, crude protein content and crude fibre content. Nineteen of the hybrids were good specific combiners for I7f7^^ ni green fodder yield. Seventeen hybrids were good specific combiners for lower crude fibre content. Pi X ??, P2X P7, P5X P7 and P5X Pg were selected based on high green fodder yield, dry matter yield, higb protein content and low fibre content for raising F2 population. F2 families of these four hybrids exhibited differences among the progenies for different characters studied. Progenies of hybrid PiX P7 was identified as the best superior cross combinant useful for further improvement for superior variety development.ThesisItem Open Access Alleilic difference in the putative gene ipk1 sequence and phytic acid (INSP6) content in Black Pepper(Department of Plant Breeding & Genetics, College of Agriculture, Padannakkad, 2019) Gladish Mary, Joy; KAU; Sujatha, RBlack pepper (Piper nigrum L.) is one of the world’s highly demanded and most traded spices with high medicinal and therapeutic values. A unigene pnc135 (995 bp) was developed by the Expressed sequence tags data obtained by next generation sequencing. This unigene was found to show similarity with ipk1 gene reported in other crop species which encodes for inositol pentakisphosphate-2 kinase enzyme (Unpublished data, Sujatha,R.). This enzyme is involved in the phosphorylation of inositol pentakisphosphate to inositol hexakisphosphate or phytic acid (InsP6), last step in the biosynthetic pathway of phytic acid. This unigene was later partially sequenced (1072 bp) towards the 3’ end by directional genome walking by Giridhari (2017). Phytic acid functions as the major storage form of phosphorus in seeds, cereals and legumes possessing significant benefits including signalling, plant communication, messenger RNA transport etc. However, phytic acid also acts as an anti-nutrient in animals as its chelating property will cause malnutrition in organisms and also leads to environmental pollution due to phosphorus excretion by non-ruminant animals. Therefore researchers are finding ways to create ipk1 mutants for either to decrease or increase the phytic acid content in organisms. However the genetic information about the black pepper crop remains very limited and the metabolic pathways and the genes related to it are also poorly understood. So in this study entitled “Allelic difference in the putative gene ipk1 sequence and phytic acid (InsP6) content in black pepper (Piper nigrum L.)”, the objective was to find out the flanking region towards the 5’ region of pnipk1 gene fragment (1072 bp) reported earlier by Giridhari (2017), to identify the allelic differences in pnipk1 gene in 10 black pepper genotypes and to estimate and quantify the phytic acid content in these 10 black pepper genotypes using polyacrylamide gel electrophoresis (PAGE). Genomic DNA was isolated from Panniyur 1 variety of black pepper and used it for the whole genome amplification by Rolling Circle Amplification method using Phi 29 DNA polymerase and walker adaptors (WA1, WA2, WA3 and WA4) reported by Reddy et al. (2008). After whole genome amplification, genome walking using primer combinations of walker primers, locus specific primers and nested locus specific primers were performed to find out the flanking region towards the 5’ region of pnipk1(1072 bp) gene fragment of black pepper. The walker primers (WP1 and WP2) used for genome walking were same as that of reported in Reddy et al. (2008) and the locus and nested locus specific primers were designed on the basis of pnipk1 gene fragment (1072 bp) sequenced by Giridhari (2017). From the nested PCR amplification four products, two amplicons, A1R3 and A4R3, each at two different temperatures viz., 51.6⁰Ϲ and 56.8⁰Ϲ were obtained and sequenced. On assembling the sequences a contig of length 523 bp was obtained towards the 5’ region of pnipk1 gene fragment and this showed similarity to ipk1 gene in other crops. This 523 bp contig was assembled with ipk1 gene fragment (pnipk1-1072 bp) to get a total length of 1535 bp. The newly assembled ipk1 gene sequence (pnipk1-1535 bp) was analysed in ORF finder for the coding region and found an Open Reading Frame (ORF) with 645 bp encoding for 214 amino acids. Phylogenetic analysis of the sequence and translated amino acid sequence showed closer evolutionary relationship with that of Dendrobium catenatum. Primers were designed based upon the pnipk1 gene sequence (1535 bp) to amplify the genomic DNA of Panniyur 1 and other 10 black pepper genotypes. The selected 10 genotypes were Panniyur 5, Panniyur 7, Chettanvally, Kottanadan, Karimunda 7, Thottamundy, Karimunda kuttyatur, Payyanganam 2, PRS 160 and Chumala. Amplification of pnipk1 gene (1535 bp) was obtained from genomic DNA of Panniyur 1, Panniyur 5, Panniyur 7 and Karimunda 7 with the expected of amplicon size indicating a similar sequence among these genotypes. Whereas amplification was not obtained in genomic DNA in rest of the genotypes showing allelic variation is present for ipk1 gene in these genotypes. To estimate and quantify the phytic acid content in Panniyur 1 and 10 black pepper genotypes, polyacrylamide gel electrophoresis (PAGE) was performed. Phytic acid was extracted from black pepper varieties same as that of selected for allelic difference analysis in ipk1 gene (pnipk1-1535 bp). The samples were loaded with phytate standards and band intensities of each concentration were determined with Gelquant.NET. The values of phytic acid in black pepper genotypes were estimated by the standard curve. The quantity of phytic acid in samples are: Panniyur 5 with 502.5nmoles/g, Panniyur 7 with 367.5nmoles/g, Chettanvally-511.5nmoles/g, Kottanadan-463.5nmoles/g, Karimunda7- 387nmoles/g, Chumala-201nmoles/g, Karimunda kuttyatur-637.5nmoles/g, Payyanganam 2-196.5nmoles/g and Panniyur 1- 275 nmoles/g, Thotamundy- 198nmoles/g, PRS 160-697.5nmoles/g. Based on the phytic acid content in the black pepper genotypes, they can be classified into low (<210 nmoles/g), medium (210-510 nmoles/g) and high (>510 nmoles/g) phytic acid content. The ipk1 gene fragment (pnipk1-1535 bp) was amplified in the genotypes Panniyur 1, Panniyur 5, Panniyur 7 and Karimunda 7. These genotypes all came under the category of medium phytic acid content group. The study resulted in sequencing a total of 1535 bp long segment of ipk1 gene black pepper variety Panniyur 1 and analysing the presence of allelic variation in ipk1 gene and phytic acid content in selected black pepper genotypes.ThesisItem Open Access Marker assisted selection for heat tolerance in rice (Oryza sativa L.)(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2019) Silpa, V; KAU; Sindhumole, PRice is highly susceptible to heat stress, particularly during the reproductive and ripening stages. In the major rice growing tracts of Kerala viz., at Palakkad, Kole and Kuttanad, the temperature tends to rise up to 40 ºC or more during the second/third crop. Consequently, high temperature induced sterility has become a serious problem. To tackle this, high yielding varieties coupled with heat stress need to be developed. As most of the prevalent high yielding rice varieties in Kerala including Uma are highly susceptible to heat stress. It is therefore, essential to impart heat tolerance to such varieties which are cultivated to a very large extent. Marker assisted selection (MAS) has been identified as a dependable, reproducible and time saving strategy to confirm the presence of desirable gene and to quicken the breeding cycle. A study conducted for the identification of SSR markers linked to the genes for heat tolerance in rice through bulked segregant analysis approach using F3 population of the cross Uma x N22 revealed that microsatellite marker, RM5749 was tightly linked to spikelet fertility trait under heat stress. The F4 population (59 nos.) raised from seven F3 lines that were found tolerant to heat stress comprised the base population for the present study. They were characterised morphologically and heat tolerance was scored under natural heat stress in the field conditions based on IRRI spikelet fertility classification. In the 26 F4 lines that registered more than 75 per cent spikelet fertility, foreground selection was done using RM5749. All the 26 F4 plants registered an amplicon corresponding to the heat tolerant parent N22. Background selection of these 26 lines was done using 35 markers found polymorphic between the parents Uma and N22. Seventy five F5 plants were evaluated for morphological characters. Among these, nine F5 plants (Plant nos.16.1.4, 16.1.5, 16.1.6, 31.2.3, 31.2.4, 31.2.5, 31.5.1, 31.6.6, and 31.6.9) with high spikelet fertility (60-70 %) were selected and genotyped using RM5749. These lines were further genotyped using the 35 polymorphic background markers. All the nine F5 plants recorded 54-64 % similarity to Uma genome. The highest spikelet fertility percentage was observed in plant no.16.1.5 (70.78 %) while the highest recovery of the parental genome of Uma was found in plant no. 31.2.5 (64.28 %). Backcrossing of the seven selected heat tolerant lines of F4 (lines 12, 13, 15, 16, 31, 41, and 45) with Uma as male parent resulted in production of BC1F1 seeds. However, the seedlings raised from these seeds did not survive under field conditions. The results obtained thus indicated that the nine lines selected in the present study are to be evaluated in further generations morphologically inorder to isolate genotypes with tolerance to heat stress.ThesisItem Open Access Development of stabilised population of cowpea segregants(Vigna unguiculata (L.) walp.) with high protein content and grain yield(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2019) Ashni Varghese; KAU; Jiji JosephCowpea (Vigna unguiculata (L.) Walp.) is an important pulse crop providing good source of protein and often referred to as poor man’s meat. It is a versatile crop, of which seeds are utilised as pulse, green pods as vegetable, leaves as forage and helps in restoring soil fertility. Many reports have indicated protein content of more than 30 per cent in certain cowpea genotypes, but at the cost of yield. Hence, the present study was proposed to develop cultures with high grain yield and protein content. The present study was conducted at Department of Plant Breeding and Genetics, College of Horticulture during 2017-2019. Twenty three lines with high yield and protein content in the F3 generation of two cowpea crosses H10 (Anaswara X PKB 3) and H11 (Anaswara X PKB 4) identified in previous studies formed the working material. These lines were evaluated in F4, F5 and F6 generations and pedigree selection was performed to select superior plants. Observations were recorded on 12 characters viz. plant height, number of branches, days to first flowering, days to first harvest, days to last harvest, number of pods per plant, length of pod, pod weight, number of seeds per pod, hundred seed weight, grain yield per plant and protein content. The F4 generation of both the crosses exhibited lower mean value for most of the characters than the parent Anaswara, but recorded moderate to high variance and range. Higher mean value was observed for days to first flowering, first harvest, last harvest, number of branches and protein content. Genetic parameters indicated that GCV was moderate for length of pod, number of seeds per pod, and hundred seed weight and high for grain yield per plant. High heritability coupled with moderate to high genetic advance was recorded for number of pods per plant, number of seeds per pod, hundred seed weight, and grain yield. Correlation studies in F4 generation revealed that grain yield was positively correlated with plant height, number of branches per plant, number of pods per plant, length of pod, pod weight, number of seeds per pod and test weight. There was non-significant correlation between grain yield and seed protein content. Further path analysis confirmed that high positive direct effect on grain yield was given by pods per plant, number of seeds per pod and hundred seed weight. Based on these observations, characters like number of pods per plant, hundred seed weight and number of seeds per pod were simultaneously included along with grain yield for setting selection criteria to select superior individual plants. Based on these set criteria, 13 individual plants from cross H10 and 10 plants from cross H11 were selected and forwarded to F5 generation. In F5 generation, mean values for number of branches, number of pods per plant, number of seeds per pod and protein content were higher than that of Anaswara with sufficient variance and range. GCV was moderate for number of branches, length of pod, pod weight, hundred seed weight and grain yield per plant. High heritability with moderate to high genetic advance was recorded for number of pods per plant, length of pod, pod weight, number of seeds per pod, hundred seed weight and grain yield. Based on the segregation pattern observed, the plants were grouped into two different categories - one with medium long pods and small seeds closely packed within the pod and the other type with long fleshy pods and bold seeds. Hence, separate selection criteria was developed for both the types comprising of characters like number of pods, number of seeds per pod, pod length, hundred seed weight, grain yield and protein content. Based on these set criteria, five individual plants from cross H10 (one type 1 and four type 2) and 17 plants from cross H11 (five type 1 and twelve type 2) were selected and forwarded to F6 generation. In F6 generation, mean value was higher than Anaswara for number of pods per plant but lower for plant height, days to first flowering, days to first harvest, days to last harvest, pod length and hundred seed weight. For other characters, mean value was comparable to Anaswara. Moderate GCV value was recorded for length of pod, pod weight and hundred seed weight. High heritability with high genetic advance was recorded for length of pod, pod weight and hundred seed weight. Separate selection criteria was developed for the two categories of plants and total five individual plants were selected, one from cross H10 and four from cross H11. The selected plants from F6 generation were subjected to organoleptic evaluation to find its suitability to be used for vegetable purpose. Three plants of type 2 and one plant from type 1 were found promising. The identified lines, H11-3.9-1-7-13-7, H11-3.9-1-1-18-13, H11-49.7-1-8-10-15, H10-71-16-1-9-15-12, and H11-2-20-3-14-16-12 can be evaluated in replicated yield trials and tested for stability over locations and seasonsThesisItem Open Access Genetic analysis of cocoa (Theobroma cacao L.) hybrids and screening superior hybrids for major biotic stress(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2019) Shillpa, K S; KAU; Minimol, J SCocoa is a crop highly influenced by climate change and growing environment, which make it necessary to have long term and dynamic breeding programme. Yield improvement was the prime objective of most of the earlier breeding programmes. However, with the emergence and spread of many diseases and pests, more emphasis is given for evolving disease and pest tolerant cocoa varieties, without sacrificing yield. At present, one of the main challenges faced by cocoa growers is Phytophthora pod rot caused by Phytophthora palmivora. Since this disease is prevalent during rainy season it is very difficult to control using fungicides. Cultivation of resistant varieties is the most effective and ecofriendly method of control. Tea mosquito bug (TMB) (Helopeltis theivora) is a major sucking pest of cocoa causing damage to young shoots, cherelles and pods. The development and use of mirid resistant cocoa varieties is the only effective alternatives to chemical control against TMB. Twenty cocoa hybrids evaluated in the comparative yield trail (CYT) were considered for the present study. Morphological characterization of the hybrids were carried out based on quantitative and qualitative characters. Thirteen pod characters, twelve floral characters, six bean characters and flush colour of leaves were studied. Except colour of petal and number of ridges and furrows, all other characters expressed high variability among the hybrids. Hybrids were also evaluated based on biochemical properties of beans including fat content, total polyphenol content and total antioxidant activity. Hybrids exhibited significant difference for biochemical characters. More over phenol content showed significant correlation with antioxidant activity. Based on biochemical and economic characters hybrids were scored and ranked. Six hybrids having top rank were selected as superior genotypes and they are PII 12.11, PIV 19.9, VSDI 33.4, VSDI 11.11, VSDI 29.9 and PIV 59.8. II The twenty cocoa hybrids included in the study were screened for Phytophthora resistance by artificially inoculating Phytophthora culture on detached cocoa pods. Based on the disease resistance reaction, the hybrids were classified using the score chart. Hybrids exhibited differential response towards Phytophthora pod rot resistance screening. Hybrids PIV 59.8, VSDI 10.13, VSDI 11.11 and PIV 31.9 were found to be highly resistant whereas, hybrids PII 12.11, SIV 5.15, SIV 1.6, PIV 26.8 and VSDI 29.9 exhibited resistance towards Phytophthora. Correlation studies between Phytophthora pod rot resistance and pod husk biochemical properties revealed that pod husk phenol and pod wax content are positively correlated to Phytophthora resistance. Artificial screening for TMB resistance was carried out on budded plant and detached pods to study the reaction of different hybrids against Helopeltis theivora. Budded plants of all the hybrids and medium matured freshly collected pods of selected six hybrids were screened. Based on the number of feeding punctures, hybrids were grouped into different classes following score chart. Hybrids PIV 59.8, PIV 60.9, PII 12.11, VSDI 33.4 and PIV 56.9 with average number of feeding punctures less than three on plants were included in highly resistant class. When cocoa pods of six hybrids were screened for TMB resistance, PII 12.11 and VSDI 33.4 had the least number of feeding punctures after 72 hours of feeding by TMB. Among the six hybrids selected based on economic and biochemical performance, five hybrids i.e. PII 12.11, VSDI 33.4, VSDI 29.9, VSDI 11.11 and PIV 59.8 exhibited highly resistant to slightly resistant reaction towards both the biotic stress considered.ThesisItem Open Access Identification of cherry tomato genotypes from f3 segregants of intraspecific cross(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2019) Pamarthi Vinod; KAU; Jayalakshmi, V GThe present study entitled “Identification of cherry tomato genotypes from F3 segregants of intraspecific cross” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2018 - 2019 with an objective to evaluate F3 segregants of the cross between cultivated tomato variety Anagha (Solanum lycopersicum L.) and Solanum lycopersicum var. cerasiforme for morphometric traits and fruit quality specific to cherry tomato and genotyping the superior segregants with SSR markers. The materials chosen for the experiment was obtained from five F2 plants selected from the cross between Anagha (Solanum lycopersicum L.) and Solanum lycopersicum L. var. cerasiforme (LA2805) done in a completed Ph.D. project of the department. A total of 150 F3 segregants from thirty plants from each F2 family was used for the study. Observations on nine morphometric traits were recorded in the F3 segregants and based on that twenty superior segregants were selected. These twenty segregants were subjected to fruit quality analysis and molecular marker analysis. Since the F3 segregants were originated from five F2 families the interfamily and intrafamily variation for each character was assessed. Among the morphometric traits, plant height did not show much variation between families and within family. Plant height of selected genotypes showing determinate to semi-determinate growth habit with a maximum of 261 cm and a minimum of 72 cm indicating selection in these segregants can lead to the development of a determinate cherry tomato variety. Weight of fruit did not show much variation between the families but within the family there was much variation, all the segregants except (P-3-17)- 11 had fruit weight higher than LA2805 and (P-1-21)- 4 is having almost double the fruit weight of LA2805 parent. Number of fruits cluster-1 of all the segregants were less than LA2805. So, more emphasis should be given on this trait in the selection in further generations. Dendrogram based on morphometric and fruit quality data revealed that the selected superior F3 segregants grouped into two major clusters. Anagha formed an individual cluster and remaining F3 segregants along with LA2805 constituting major cluster indicating all the small fruited cherry tomato genotypes grouped into one cluster. Analysis for qualitative traits (Lycopene, vitamin C, pH and TSS) showed that lycopene showed variation between the families and within the family. Lycopene content of all the segregants except (P-3-17)- 11 was higher than LA2805. This is a good indication as higher lycopene content is a valuable character with respect to quality of cherry tomato. Vitamin C content of two of the segregants (P-2-11)- 6 and (P-3-17)- 11 were higher than LA2805 parent indicating this character will have scope for selection in further generations. Intrafamily variation was seen for all the characters except for pH which showed a constant around 4 with maximum pH recorded in (P-5-27)- 20. TSS (%) of fruits did not show much variation between the families but within the family there was much variation with maximum TSS (%) of 6.8 was recorded in (P-3-17)- 11. Molecular marker analysis was done using ten SSR markers reported as specific to cherry tomato. Out of the twenty segregants, the segregants (P-1-21)- 4 and (P-2-11)- 6 showed the presence of all the SSR markers linked to cherry tomato. The segregants (P-2-26)- 8, (P-3-17)- 11, (P-4-8)- 14 showed eight specific markers of cherry tomato. A proximity dissimilarity matrix was constructed between the selected segregants and the parents based on the recorded morphometric and fruit quality data. The results of the data revealed that distance from the cherry tomato parent was less than 9.00 indicating that these selected superior segregants were showing more to cherry tomato morphometric and fruit quality traits. The segregants (P-2-26)- 8, (P-3-17)- 11 and (P-4-8)- 14 which had Euclidean coefficient of dissimilarity assessed based on morphometric and fruit quality traits 4.22, 4.60 and 6.19 respectively showed eight specific markers linked to cherry tomato. The segregants (P-1-21)- 4 and (P-2-11)- 6 which showed the presence of all the ten specific markers to cherry tomato had Euclidean coefficient of dissimilarity of 5.54 and 6.53 respectively. Based on the morphological, biochemical and molecular data five F3 segregants (P-1-21)- 4, (P-2-11)- 6, (P-2-26)- 8, (P-3-17)- 11 and (P-4-8)- 14 were selected to carry forward to further generations for getting a cherry tomato variety with determinate growth habit, higher fruit weight, high number of fruits cluster-1, high lycopene and vitamin C content.ThesisItem Open Access Variability in horsegram(macrotyloma uniform(Lam) verdc): under open and partially shaded conditions(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2019) Swathy Sivan; KAU; Arya, KThe present study entitled “Variability in horsegram [Macrotyloma uniflorum (Lam.) Verdc.] under open and partially shaded conditions” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2017-2019. The study was undertaken to assess the variability and performance of horsegram genotypes collected from different regions under open and partially shaded conditions, for yield and protein content. Thirty genotypes of horsegram were collected from different regions of state and outside and were raised under open and partially shaded conditions, simultaneously for variability analysis. The partial shade was provided by coconut garden, planted at a spacing of 7.8 x 7.8 m, where the average shade percent was 24. These accessions were evaluated in a Randomized Block Design (RBD) with three replications during September 2018 to February 2019. Analysis of variance revealed significant difference among the genotypes for all the fifteen characters studied. Pooled analysis was also conducted for all the characters to compare the performance of genotypes under open and partially shaded conditions. The genotypes exhibited significant difference for characters such as number of primary branches plant-1, days to 50% flowering, days to maturity, number of pods plant-1, harvest index, crop duration and seed yield plant-1 under the two conditions. Under both conditions, genotypic coefficient of variation (GCV) was high for seed yield plant-1 and number of pods plant-1 while, characters like primary branches plant-1, secondary branches plant-1, pods plant-1, seed yield and harvest index exhibited high values for phenotypic coefficient of variation (PCV). High heritability coupled with high genetic advance was observed for seed yield plant-1, days to sprouting, days to 50% flowering, nodes plant-1, pods plant-1 and plant height under both conditions whereas, under partially shaded conditions, two more characters such as primary branches plant-1 and harvest index also showed high heritability with high genetic gain. Seed yield plant-1 was found to be significantly and positively correlated with number of primary branches plant-1, number of secondary branches plant-1, nodes plant-1, pods plant-1, seeds pod-1 and 100-seed weight both at genotypic and phenotypic levels under open and partially shaded conditions. An improvement in these characters would lead to an enhancement in the seed yield plant-1. Path analysis was carried out using seed yield plant-1 as the dependent character and other characters as independent variables. It revealed that number of pods plant-1, seeds pod-1, nodes plant-1, 100-seed weight, days to maturity and number of primary branches plant-1 were the primary yield contributing characters due to their high direct effect on seed yield plant-1. Genetic divergence was studied under open conditions using Mahalanobis’ D2 statistics and based on this analysis, the thirty genotypes were grouped into eight clusters. The maximum number of genotypes were accommodated in Cluster I (12), followed by Cluster II (6), Cluster III (5), Cluster IV & Cluster V with two genotypes each and Clusters VI, VII and VIII were solitary. Among the eight clusters, the highest inter cluster distance was recorded between Clusters V and VIII, while Cluster V also exhibited maximum intra cluster distance. It was observed that among the individual traits, seed yield plant-1 contributed highest for divergence followed by primary branches plant-1 and days to maturity. The results of the study revealed the presence of wide variability among the thirty horsegram genotypes under open and partially shaded conditions. The genotype T12 (Palakkad local) was found to be superior in yield performance both under open (20.08 g) and partially shaded conditions (18.36g), followed by the genotype T2 (Chintada local) from Andhra Pradesh (19.82g, 17.75g). Also the genotype T21 (IC22762) (18.22g) was found to be a high yielder under open conditions and genotype T17 (Attapadi local) (16.99g) under partially shaded conditions. When protein content was assessed, maximum value (28.92%) was recorded for genotype T14 (Dharmapuri local) under open conditions and genotype T23 (IC15735) (29.17%) under partially shaded conditions. The superior genotypes identified in the present study can be utilized for further crop improvement programmes to develop high yielding varieties.ThesisItem Open Access Genotypic evaluation and in vitro multiplication of anthurium (Anthurium andreanum linden) hybrids(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2019) Anand, S; KAU; Beena ThomasThe present study entitled “Genotypic evaluation and in vitro multiplication of anthurium (Anthurium andreanum Linden) hybrids” was carried out at the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, during 2017-19. The study was undertaken to evaluate anthurium hybrids for commercial qualities and their mass multiplication through in vitro techniques. For variability analysis, 20 Anthurium andreanum Linden hybrid genotypes maintained at the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani were utilized. When the selected hybrids were evaluated in completely randomized design with five replications, wide range of variations were observed among the qualitative as well as quantitative traits. The mean number of inflorescence year-1 ranged between 6.4 (HR x MR) and 2.2 (CR x KR). Spathe size was maximum for HoR x KR (112.30 cm2) and the minimum for HR x MR (27.60 cm2). The longest post-harvest vase life was observed for HoR x KR (24.4 days) which was on par with LJ x OG (23.4 days). The components of variation namely genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were analysed. High PCV and GCV were observed for the characters number of suckers plant-1, number of leaves spadices-1 plant-1 year-1, spathe size, leaf area, number of flowers spadix-1, spadix length, duration of interphase, inclination of candle with spathe, anthocyanin content, vase life and number of inflorescence year-1. Thus, selection for these characters would result in improvement of the genotype. High heritability coupled with high genetic advance were observed for plant height, leaf area, number of leaves spadices-1 plant-1 year-1, spathe size, spadix length, number of flowers spadix-1, days to initiation of female phase, duration of female phase, inclination of candle with spathe, anthocyanin content, vase life and number of inflorescence year-1. This indicated that expression of these traits were controlled by additive gene action and improvement could be achieved for these traits by direct phenotypic selection. Correlation analysis with genotypic correlation coefficients revealed significant positive correlation of number of inflorescence year-1 with characters such as number of leaves spadices-1 plant-1 year-1, number of suckers plant-1 and vase life. An improvement in positively correlated characters would enhance the number of inflorescence year-1. Path coefficients were worked out with number of inflorescence year-1 as the dependent variable and other correlated characters as component variables revealed that all the three positively significant, correlated characters had positive direct effect with the dependent variable. Path analysis further proved direct association of traits such as number of leaves spadices-1 plant-1 year-1, number of suckers plant-1 and vase life with flower yield of anthurium hybrids accounting for more than 70 per cent of variation in flower yield. From experiment I, six hybrid genotypes namely HR x MR, LJ x OG, OG x NO, HoR x KR, PR x HR and HR x LR with superior flower yield attributing traits and qualitative characters were selected for in vitro mass multiplication study. For in vitro culture, pale greenish brown young leaf lamina, 5 to 10 days after unfolding of leaf, collected from healthy and mature plants were used as explant. Proper control measures were taken for control of bacterial blight and anthracnose diseases so as to obtain disease free explants. Surface sterilization of leaf explants with 5.0 per cent sodium hypochlorite for 10 minutes followed by 0.1 per cent mercuric chloride for 5 minutes was found to be the best and resulted in 87.5 per cent explant survival. For all the hybrids the highest callus induction percentage was recorded by modified half strength MS medium supplemented with 200 mg L-1 NH4NO3 + 1.0 mg L-1 BA + 0.5 mg L-1 2,4 D + 30 g L-1 sucrose + 6.0 g L-1 agar. The explants were cultured in darkness for callus induction and later the callus was subcultured in the same culture medium for two months for multiplication. For shoot regeneration, the multiplied callus was subcultured to regeneration medium and a photoperiod of 16 hours light and eight hours dark was provided. Of the various regeneration treatments, half strength MS medium supplemented with 0.5 mg L-1 BA showed shoot initiation response ranging from 50.0 (LJ x OG and HR x LR) to 87.5 (OG x NO and HoR x KR) per cent among the hybrids. The fastest shoot regeneration was observed for the hybrid HR x MR (62.20 days) and slowest for LJ x OG (77.25 days). Rooting response preceded shooting response in all the hybrids in the same regeneration medium. To summarize the research results revealed the presence of wide range of variability among the 20 anthurium hybrid genotypes for the 29 characters studied. Most of the quantitative traits were controlled by additive gene action permitting direct selection for improvement. Traits such as number of leaves spadices -1 plant-1 year-1, number of suckers plant-1 and vase life had positive significant correlation and direct association with flower yield in anthurium hybrids. Genotypic differences were evident from in vitro mass multiplication studies on the six superior hybrids. Modified half strength MS medium supplemented with 200 mg L-1 NH4NO3 + 1.0 mg L-1 BA + 0.5 mg L-1 2,4 D + 30 g L-1 sucrose + 6.0 g L-1 agar was the most suitable for callus induction and callus multiplication while shoot initiation, proliferation of shoot and root were the highest and faster in the same basal medium supplemented with 0.5 mg L-1 BA. Large scale multiplication of the superior hybrids and profit generation can be achieved through the tissue culture protocol that was standardized in the present study. The promising commercially superior anthurium hybrids identified in the study can be used in further crop improvement programmes.