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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 Embargo Genetic diversity analysis for nutrient efficiency and identification of nutrient responsive genes in cassava (Manihot esculenta Crantz)(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2023-02-10) Swathy Sivan; KAU; Arya, KThe present study entitled “Genetic diversity analysis for nutrient efficiency and identification of nutrient responsive genes in cassava (Manihot esculenta Crantz)” was carried out in the Department of Plant breeding and Genetics, College of Agriculture, Vellayani and Division of Crop Improvement, ICAR-CTCRI, Sreekariyam, during 2019-2022. The study was undertaken to screen and characterize N and K-efficient genotypes in cassava and identify the traits contributing to nutrient efficiency and study their gene expression. Thirty genotypes of cassava comprising of landraces, released varieties and pre-release accessions from ICAR-CTCRI and KAU were taken for the study. Field evaluation was done to identify low input nutrient efficient lines where analysis of variance revealed significant difference among the genotypes for all the characters studied except the girth of tuber. High GCV, PCV, heritability and genetic advance were observed for traits like tuber yield, N and K efficiency, plant height, number of leaves, number of branches, stem N and K content. Tuber yield was positively correlated to N and K efficiency, plant height, leaf and stem weight, stem girth, mean weight of tubers, number of nodes, girth and length of tubers, while negatively correlated to tuber starch and dry matter content. Path analysis showed that tuber length gave highest positive direct effect on yield followed by number of tubers, number of leaves, tuber starch content, plant height and nitrogen efficiency. Diversity studies grouped the genotypes into eleven clusters and the characters that gave the maximum contribution to divergence were tuber dry matter content, N and K efficiency. Root studies on thirty genotypes revealed that root traits like number of nodal roots, basal roots, adventitious roots, storage roots and root length displayed significant positive correlations with N and K efficiency. Evaluation of five highly nutrient efficient genotypes at the three levels of fertilizers (0%, 25% and 50% of the recommended dose of fertilizers) showed overall significance for traits like plant height, the number of leaves retained, stem weight per plant, girth of the stem, tuber yield, length of tuber, stem K content, tuber K content, total N and K uptake, N and K efficiency. The highest yielder was KBH 18 followed by 8S501-2. Maximum N efficiency was observed for KBH18 followed by 15S409, while maximum K efficiency was recorded for 8S501-2 followed by 15S409. Results showed that from 0 to 25 % there is an escalation in tuber yield as well as N and K efficiency, while the values at 25 and 50% are on par. All the selected four genotypes showed significant superiority over the K efficient check variety – Sree Pavithra – in terms of tuber yield, N efficiency and K efficiency. The study identified nine nutrient responsive genes in cassava which includes NRT1, NRT3, NLP1, GPT2, AMT1, TAR2 for nitrogen and KUP3, KUP4, KUP8 for potassium. Expression studies done using these genes in contrasting genotypes for N and K efficiency raised under field conditions showed significant upregulations and downregulations in their expression for efficient and less efficient genotypes. Allele mining for allelic variations in contrasting genotypes (15S409 and Export kappa) for two genes (AMT2 and NTR3) didn’t show much significant variation. Although SNP differences were observed for NRT3 gene, further functional studies are required to confirm this result. The study identified three main nutrient efficient genotypes viz., KBH18, which was the highest yielder, highest in N efficiency and third highest in K efficiency, 8S501-2, which was second highest in yield, highest in K efficiency, third highest in N efficiency and also exhibited early bulking and 15S409, which was the third highest yielder, second highest in N efficiency & K efficiency. The superior genotypes identified in the present study can be subjected to field trials for confirming their superiority and release as a variety.ThesisItem Open Access Genetic variability, path analysis and stability parameters in sesame(Department of Plant Breeding, College of Agriculture, Vellayani, 1985) Sverup, John; KAU; Gopinathan Nair, VBiometric analysis in a varietal collection of sesame was undertaken to study the genetic variability, correlations, path analysis and stability parameters. One hundred sesame types were evaluated in replicated trials at Vellayani in uplands during rabi and at Kayamkulam in rice fallows during summer. Genetic variability and correlations were estimated and path analysis worked out independently as both the locations. Location trials for estimating stability parameters were conducted at three places viz. in uplands during rabi at Pattambi and Vellayani and in rice fallows during summer at Kayamkulam. Large values for genotypic coefficients of variation were obtained for characters such as number of capsules on branches, number of capsules perplant, number of capsules on main stem and number of branches during rabi as well as summer. The lowest genotypic coefficient of variation was obtained for number of days to maturity during both rabi and summer. High values of heritability were recorded by seed protein content , seed oil content, height upto first capsule and weight of 1000 seeds under both conditions.ThesisItem Embargo Gene action and gene expression analysis in yardlong bean(Vigna unguiculata ssp. sesquipedalis(L.) Verdcourt) for drought tolerance(Kerala Agricultural University, 2022) Rahana, S N; KAU; Beena, ThomasThesisItem Open Access Characterization and identification of black pepper accessions (Piper nigrum L.) for stress tolerance and quality(Department of plant breeding, College of Horticulture, Vellanikkara, 2019) Prakash, K M; KAU; Jiji, JosephBlack pepper (Piper nigrum L.), often described as the ‘King of spices’ is the most important spice crop, grown for its berries in the world. Indian pepper is preferred across the globe due to its intrinsic qualities. Foot rot is a devastating disease of black pepper. In the changing climate, drought can be a major threat in black pepper production. Hence, the present study was taken up at College of Horticulture, Vellanikkara and ICAR-IISR, Kozhikode to characterise and to identify superior accessions of black pepper for yield, quality and tolerance to biotic and abiotic stresses. Fifty accessions of black pepper in the bearing stage maintained in the National Active Germplasm Site of ICAR-IISR, Kozhikode formed the base material for the study. The accessions were characterised for fifty qualitative and fifty quantitative characters following the descriptor developed by IPGRI (1995). Wide variability was observed among the accessions for ten qualitative characters. Quantitative characters of shoot, leaf, spike and fruit also showed wide variability. Field tolerance to foot rot disease and pollu beetle infestation was observed among the accessions. Twenty accessions were selected from the base collection based on superiority of yield (> 450g green berries/vine) , field tolerance to foot rot disease infection (biotic susceptibility score 1) and pollu beetle infestation (biotic susceptibility score 1-3). They were further evaluated for biochemical principles of quality, tolerance to foot rot disease under artificial inoculation and tolerance to drought by physiological and biochemical analyses. Piperine, essential oil and oleoresin ranged from 3.61 - 6.96 per cent, 3.00 - 5.87 per cent and 7.10 - 11.18 per cent, respectively, across the accessions. The accessions with high value of piperine, essential oil and oleoresin were identified as 7293, 7211 and 7289 respectively. The two accessions identified viz. 7293 and 7252 contained more piperine than the highest of Panniyur 2 (6.6 per cent) reported among the released varieties . Artificial inoculation of selected accessions using Phytophthora capsici culture for screening for foot rot disease resistance based on over all disease severity index of both stem and leaf lesions showed that accession 7259 was moderately resistant. The selected accessions did not exhibit significant variation for various physiological and biochemical parameters at field capacity. However higher value of photosynthesis, chlorophyll content, chlorophyll stability index, relative water content and membrane stability index and low leaf temperature were observed for accessions viz. 7215, 7240, P 5 and 7241 after five days and ten days of moisture stress induction following field capacity compared to other accessions. Higher values of proline, SOD, catalase and peroxidase were also observed for these accessions. The visual scoring showed that accessions with higher values for most of physiological and biochemical parameters of drought tolerance viz. 7215, 7240, P5, and 7241 had lesser number of fallen leaves and more number of leaves retained at permanent wilting point (PWP). The accessions 7215 and 7240 took twenty days to reach PWP compared to eleven accessions which took only 16 days to reach PWP. Foliar nutrition with sulphate of potash, IISR - Power mix and Pink Pigmented Facultative Methylotrophs (PPFM) had positive effect on drought tolerance for the accessions (7215, 7240, P5 and 7241) having natural tolerance. The identified accessions with high yield , quality and tolerance to biotic or abiotic stress can be used for further breeding programme.ThesisItem Open Access Heterosis breeding in sesame (Sesamum indicum L.).(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2011) Gayathri, G; KAU; Dijee, BastianThe study entitled ‘Heterosis breeding in sesame (Sesamum indicum L.)’ was undertaken at the Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara. The objectives of the study were to collect and evaluate different genotypes of sesame for morphological traits and yield attributes, to identify useful parents producing heterotic crosses and developing hybrids in sesame. The study also intended to develop male sterile lines in sesame through interspecific hybridization with Sesamum malabaricum. Sesamum indicum and Sesamum malabaricum accessions were collected from Kerala and Tamil Nadu and evaluated for their morphological traits. Wide range of variation was noticed for characters like plant height, number of days to flowering and seed yield per plant which contributed maximum to genetic divergence. The genotypes studied were grouped into six clusters. High genotypic coefficient of variation (GCV) was recorded for number of capsules per plant, plant height, seed yield per plant and number of branches per plant. High heritability with high genetic advance as per cent of mean was recorded for number of days to flowering, plant height, number of branches per plant, number of capsules per plant and seed yield per plant. This indicates that the characters are governed by additive gene effects and selection for these traits will be effective. Association analysis revealed that seed yield per plant was correlated to plant height, number of capsules per plant and number of days to flowering. Path coefficient analysis indicated maximum positive direct effect by number of capsules per plant, capsule length, plant height and 1000 seed weight on seed yield per plant. In order to develop hybrids, fourteen parents were selected based on the per se performance of the genotypes. They were crossed in line X tester mating design. Forty eight hybrid combinations obtained were raised in the field along with the parents and evaluated for their heterosis and combining ability effects. Parental genotypes AVTS-06-5, AVTS-06-10, IVTS-06-12, KYM-1, Tilak and TMV-6 were identified as high combiners based on general combining ability (gca) effects. Two combinations viz. AVTS-06-5 X KYM-1 and IVTS-06-12 X TMV-3 had significant values of per se performance, specific combining ability (sca) effects and standard heterosis for seed yield per plant. They can be evaluated for their hybrid vigour over locations and seasons. The crosses AVTS-06-5 X TMV-3, AVTS-06-5 X TMV-6 and TCR 3279A X KYM-1 have been identified as potential cross combinations for isolation of promising segregants as the parents involved in these crosses had high significant gca effects for seed yield per plant but the hybrids recorded non significant sca effects. Interspecific hybridization between S.malabaricum and S.indicum was attempted to develop male sterile lines. Seed set was noticed in three interspecific hybrids which failed to germinate due to embryo abortion. Hence these embryos were rescued and raised in vitro to obtain the hybrids.ThesisItem Open Access Genetic divergence, prepotency and inbreeding depression in para rubber (Hevea brasiliensis Muell. Arg.)(Department of Plant Breeding, College of Agriculture, Vellayani, 1992) Kavitha Mydin, K; KAU; Gopinathan Nair, VA study on genetic divergence, prepotency and inbreeding depression in rubber was undertaken in an effort to identify clones for use as components of polyclonal seed gardens. Forty clones of Indian, Indonesian, Malaysian and Sri Lankan origin were evaluated in a replicated trial at the Rubber Research Institute of India. Genetic variability, correlations and the cause and effect relationships of dry rubber yield and its components were worked out. Genetic divergence was estimated employing the Mahalanobis' D2 techinique. The factors of divergence were identified through principal factor analysis. Twenty promising clones from genetically divergent clusters were subjected to seedling progeny analyses for the estimation of propotency based on performance of their open pollinated seedling progenies and inbreeding depression in the first generation of selfing. Significant clonal variation was revealed in respect of all the physiological, morphological and structural attributes studied as mean values for the fourth year of tapping for the stress period and for the peak yield period. High genetic variability for volume of latex under stress, plugging index under stress, annual mean dry rubber yield and dry rubber yield during the stress and peak periods was indicated by the high estimates of genotypic coefficient of variation. Additive gene effects offering scope for improvement through selection was indicated for dry rubber yield, latex flow rate and volume of latex during the three periods, girth increment rate, annual mean plugging index and plugging index under stress, by the moderate to high heritability estimates along with high genetic advance for these traits. Non- additive gene action was indicated by the high heritability and low genetic advance for dry rubber content during the three periods, girth and bark thickness. At both genotypic and phenotypic levels, annual mean dry rubber yield showed moderate to high positive correlations with dry rubber content and latex flow rate during the three periods, girth, girth increment rate, length of the tapping panel and bark thickness and negative correlations with yield depression under stress and plugging index during the three periods. Dry rubber yield under stress emerged as a more important component than peak dry rubber yield by its higher magnitude of positive direct effect on annual mean dry rubber yield. Latex flow rate during the stress and peak periods and annual mean volume of latex exhibited high positive direct effects on annual mean dry rubber yield while plugging index during the peak yield period, volume of latex under stress and girth increment rate had negative direct effects on annual mean dry rubber yield. The magnitude and direction of the effects of the components on dry rubber yield during the three periods varied indicating these relationships to be under different genetic control. Selection for a high dry rubber yield under stress, annual mean volume of latex and latex flow rate during the stress and peak periods and against a high plugging index during the peak period, volume of latex under stress and girth increment rate would help achieve improvement in annual mean dry rubber yield. Considerable genetic diversity was revealed by the wide range of D2 values and intra and inter cluster distances. The forty clones were grouped into eight genetically divergent clusters irrespective of their country of origin indicating the absence of any relationship between geographical diversity and genetic divergence. Volume of latex, plugging index, latex flow rate, dry rubber content and dry rubber yield contributed more towards divergence than the morphological and structural attributes. Supporting evidence was obtained from principal factor analysis which revealed the yield factor to be the main factor of divergence with respect to the clusters studied. Junveile rubber yield on test tapping, number of latex vessel rows and number of leaf flushes in seedling progenies exhibited high heritability and genetic advance indicating scope for their use as early selection parameters, while girth exhibited high heritability and low genetic advance. These three traits showed significant positive correlations with juvenile rubber yield, of which girth exhibited the strongest association. Juvenile rubber yield, number of latex vessel rows, girth and number of leaf flushes were identified as important traits for being accorded simultaneous emphasis in the computation of performance index and index scores for the determination of recovery of superior seedlings as estimates of prepotency. Nine clones were identified as likely preopotents on the basis of seedling progeny analysis at the age of two years. Selfing resulted in a lower fruit set than open pollination in the clones in general. No significant inbreeding depression was recorded for juvenile vegetative traits and rubber yield in seedlings. Clones PB 28/83, PB 215, RRII 105, AVT 73, PB 217, PB 252, Ch 26, PB 242 and PB 5/51 were identified as likely prepotents from three genetically divergent clusters. They recorded superiority for yield and various yield components. These clones exhibited synchrony in flowering and are suggested as components of a nine parent polyclonal seed garden. For a seven parent seed garden the clones suggested to be excluded are PB 5/51 and PB 242. A polyclonal seed garden comprising these nine or seven clones as components could generate good quality polycross seed material. Appropriate seed garden layouts have been suggested.ThesisItem Open Access Genetic analysis of biological nitrogen fixation traits and yield components in cowpea (Vigna unguiculata (Linn). walp)(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 1995) Sreekumar, K; KAU; Manikantan Nair, PA study on the parameters of variability, correlations, path-coefficients, combining ability, gene action and heterosis in cowpea was undertaken at the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 1991 to 1993. Fifty three genotypes of cowpea collected from different sources were planted in a field experiment for the estimation of variability, correlation and path coefficient. Eleven biological nitrogen fixation characters, viz., number of days to flower, length of primary root, number of secondary roots, number of nodules in the primary root, number of nodules in the secondary roots, total number of nodules, weight of effective nodules in the primary root, weight of nodules in the secondary roots, total weight of nodules, nitrogen content in the plant at 50 per cent flowering and plant dry weight and six yield characters, viz., grain yield per plant, length of pods, number of pods per plant, number of seeds per pod, weight of 100 seeds and seed protein content were considered for this study. The ten selected varieties/types from the initial evaluation trial were crossed in a line x tester model, keeping the three high nitrogen fixing types and three high yielding types as lines (total six lines) and two low nitrogen fixing and two low yielding types as testers (total four testers). The F1’s along with their parents were compared in a field experiment and combining ability, gene action and heterosis were estimated. The study of combining ability and gene action were confined to six biological nitrogen fixation characters, viz., number of days to 50 per cent flowering, weight of nodules in the primary root, total weight of nodules, weight of effective nodules, dry weight of the plant and nitrogen content per plant and six yield characters, viz., length of pod, number of seeds per pod, number of pods per plant, hundred seed weight, seed protein content and grain yield per plant. The analysis of variance revealed that a considerable amount of variation among the varieties was present with respect to the characters under study. Characters like number of days to flower, total nodule weight, nitrogen content per plant, weight of 100 seeds and seed protein content had recorded narrow relative magnitude of difference of phenotypic and genotypic coefficient of variation along with high heritability estimate. Moderate magnitude of difference of PCV and GCV along with moderate heritability was recorded for the characters viz., number of nodules in the primary root, number of nodules in the secondary roots, total number of nodules, weight of effective nodules in the primary root, weight nodules in the secondary root, length of pods and number of pods per plant. Plant dry weight and grain yield registered a wider difference of PCV and GCV along with low heritability indication the greater influence of environment over these two characters. Genetic advance as percentage of mean was found to be high for the characters like number of nodules in the secondary roots, weight of effective nodules in the primary root, weight of nodules in the secondary roots, total nodule weight, number of pods per plant and 100 seed weight and moderate for number of nodules in the primary root, total number of nodules and grain yield. Low genetic advance was recorded by number of days to flower, plant dry weight, nitrogen content per plant, length of pod and seed protein content. Hence characters such as number and weight of nodules in the primary root, number and weight of nodules in the secondary roots, total number and weight of nodules, number of pods per plant and weight of 100 seeds may be controlled by additive genes whereas days to 50 per cent flowering, nitrogen content in plant, length of pod and seed protein content may be controlled by non-additive genes. Correlation coefficients were workedout at the genotypic and phenotypic levels. Based on the genetic correlation of characters studied, it was understood that high nitrogen fixing genotypes may not be high yielders because of the antagonistic relationship between grain yield and total nitrogen per plant. Weight of nodules in the primary root and total nodule weight were positively correlated with the nitrogen content in plant. Hence genotypes which was able to form effective large nodules on the primary root system seems to be a better nitrogen fixer. Number of days to 50 per cent flowering had negative genotypic correlation with grain yield. Hence an early flowering genotype may be better yielder than a late flowering type. Weight of hundred seeds and seed protein content exhibited very strong negative correlation indicating that small seeded genotypes may be better with respect to protein content. Grain yield recorded positive phenotypic and genotypic correlation with number of pods per plant. Path coefficient analysis at the genotypic level revealed that total number of nodules had the highest positive direct effect on nitrogen content per plant followed by weight of effective nodules in the primary root and weight of effective nodules in the secondary root. Highest positive direct effect was recorded for length of pod with grain yield. The combining ability analysis revealed that both additive and non-additive gene actions were important for all the characters under study. However GCA and SCA variance ratio which was less than unity for all the traits under study indicated the predominance of non-additive gene action in the inheritance of these traits. Considering the combining ability effects, VCP 4 was found to be the best general combiner for most of the biological nitrogen fixing characters and V 322 was the best general combiner for the grain yield. The cross combination of V 27 x C 152 and V 271 x Co Vu 85020 showed the best performance with respect to sea for the character number of days to 50 per cent flowering while VCP 4 x C 152 for weight of nodules in the primary root and nitrogen content in plant. DPLC 210 x PTB 2 recorded high sea for total weight of nodules, weight of effective nodules, dry weight of the plant and number of pods per plant, on the other hand Co Vu 358 x C 190 recorded high sca for length of pod, number of seeds per pod and seed protein content. The cross combination V 322 x C 190 exhibited high sca for hundred seed weight and V 27 X C 152 for grain yield per plant. Marked heterosis was observed in many cross combinations for most of the characters studied and pronounced heterotic expression was obtained for weight of nodules in the primary root, total weight of nodules, weight of effective nodules, dry weight of the plant at 50 per cent flowering, number of pods per plant and grain yield. It was already established that these characters are predominantly governed by the non – additive gene action. Hence the heterotic vigour expressed by the hybrid combination with respect to these characters are justified. Since the biological feasibility for the exploitation of heterosis is not economical as a plant improvement programme in this crop, genetic improvement of these trait can be brought about more effectively through combination breeding involving genetically diverse and high combining parants.ThesisItem Open Access Variability in asoka (Saraca asoca(Roxb.) de wilde)(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2010) Vidhu Francis, Palathingal; KAU; Radhakrishnan, V VAsoka (Saraca asoca) is a sacred tree among the Buddhists and Hindus. It is called sorrow-less tree as it removes the grief. The tree has immense medicinal properties. Its bark is mainly used for correcting uterine problems. The well-known Ayurvedic preparations of asoka bark are Asokarishtam and Asokaghrutham. Due to over exploitation of this tree for its bark, this has now become almost extinct. The International Union for Conservation of Nature and Natural Resources (IUCN) has listed this species under ‘globally vulnerable’ category. It is also enlisted among the 36 threatened and endangered medicinal plants of India. Due to its acute short supply compared to its demand, various development and research activities are being prioritized to conserve, utilize and improve this species. Therefore the present study was undertaken to assess morphological variations in existing germplasm and to study the reproductive biology of S. asoca. Collection of seeds and evaluation of seed and seedling traits, evaluation of therapeutical components and molecular characterisation of asoka were the other objectives of the study. Variability studies for morphological traits of asoka indicated that height of plant and stem girth have high correlation with bark yield as well as higher direct effect. These traits can be used for identifying better genotypes for higher bark yield. In discriminant function analysis, the selection index involving height of plant along with bark yield constituted for selection criteria among asoka genotypes. Using this selection index, accessions IC566463, IC566489, IC566488, IC566482 were selected as better accessions for higher bark yield. The 43 accessions maintained in germplasm of asoka at AICRP on M&AP were grouped into two major clusters based on morphological traits. These clusters further formed 6 clusters. Accession IC566488 grouped alone in one cluster indicated that this accession was different from all other accessions. In all the other 5 clusters, accessions from Thrissur was included. This indicated that accessions did not follow geographical distributions. Some of the accessions from Thrissur may have relationship with accessions from other districts. Reproductive biology of asoka was studied. It indicated that the reproductive traits like floral biology, anthesis, pollen morphology, its viability have variability among eight trees studied in KAU campus. Among the eight trees studied, ‘KAU8’ have better reproductive traits compared to the rest. Preliminary studies were carried out in pollination system and agents for pollination in asoka. The studies indicated that ants may be one of the pollinating agents. Seed and seedling behaviour of asoka were studied on seeds collected from 80 trees located in different districts of Kerala. Seed breadth, seed volume, height of plant and stem girth were identified as selection traits for better seedlings. Hence at seed stage, bigger sized seeds with higher seed volume will result into better seedlings. Vigorous seedlings is produced from tall seedlings with higher stem girth and in mature plants for higher bark yield, height of plant and stem girth can be selection traits. Thus the selection parameters were worked out in three stages in asoka. Based on seed and seedling selection parameters, OKL4, OKL2 from Odakkali, KKL2 from Kottakkal and TVM2 from Thiruvananthapuram were selected as better mother plants for higher bark yielding accessions. The biochemical constituents (phenol and tannin content) imparting medicinal properties were estimated among the different age groups of asoka. Both phenol and tannin contents were higher in bark compared to flower and leaves. About 50 per cent of therapeutical constituents are available in flowers and hence at non destructive level, flowers of asoka can be substituted for bark. The trees KAU8, KAU7, KAU6 and among the accessions IC566474, IC566467 and among the seedlings VKA6, VKA7, VKA8, KMK3 indicated higher phenol and tannin content compared to rest. Molecular characterisation among the selected asoka accessions representing the different districts of Kerala were studied. RAPD analysis was attempted among ten accessions selected. Dendrogram was constituted based on pooled RAPD data. The ten selected accessions were grouped into two major clusters as done in morphological grouping. In grouping at molecular level, the accession IC566488 kept apart as a single group indicating the same trend at its morphological level.The clustering pattern based on molecular characterisation did not follow geographical distribution of accessions.ThesisItem Open Access Cross compatibility analysis for production of hybrids in anthurium andreanum linden(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2010) MadhuKumar, K; KAU; Mayadevi, PThe present study, ‘Cross compatibility analysis for production of hybrids in Anthurium andreanum Linden’ was undertaken to identify suitable parents with commercial qualities and to determine the cross compatibility among the selected parents in anthurium. The present investigation was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during the period 2006-2009. The analysis of variance revealed significant variation among the 40 genotypes for the eighteen characters studied. This reveals the high genetic potential for the improvement in this crop. Variability studies indicated high phenotypic and genotypic coefficients of variation for the characters for anthocyanin content, pollen fertility, leaf size/leaf area, spathe size and spadix length. The high heritability coupled with high genetic advance values were found for characters plant height, leaf size/leaf area, internodal length, spathe size, total anthocyanin content, spadix length, inclination of candle with spathe, number of flowers per spadix, life of spadix, days to initiation of female phase, days to inter phase, duration of male phase, pollen fertility and pollen size. These characters are therefore controlled by additive gene action and amenable to genetic improvement through selection. Pollen fertility estimated using acetocarmine method indicated that most of the genotypes had low fertility values. Liver Red had the highest pollen fertility of 43.01 per cent followed by Lady Jane (36.14 per cent). Pollen emergence was low in the months from March to June, during which the average maximum and minimum temperatures were relatively high. Pollen emergence was highest during October to December months. A study of six qualitative characters such as colour of young leaf and petiole, spathe colour, spathe texture, candle colour and type of inflorescence axis also showed considerable variation among the genotypes studied. Plant height was found to have highly significant positive phenotypic and genotypic correlation with leaf size/leaf area, internodal length, total Anthocyanin content, spadix length, number of flowers per spadix and life of spadix. Number of flowers per spadix had significant positive genotypic correlation with plant height, leaf size/leaf area, internodal length, spathe size, spadix length, total anthocyanin content, life of spadix, pollen fertility and pollen size. Spadix length had significant positive genotypic correlation with plant height, leaf size/leaf area, internodal length, spathe size, number of flowers per spadix, life of spadix and pollen size. Days to initiation of female phase exhibited significant negative correlation with plant height, leaf size/leaf area, spadix length and pollen fertility. The environmental correlations were absent for almost all pairs of characters except for number of leaves/spadices per plant with spathe size. Path analysis revealed that spadix length, plant height, leaf size and life of spadix had high positive direct effect on number of flowers per spadix. Mahalanobis D2 analysis clustered the 40 genotypes into seven clusters. The maximum number of genotypes (17) were included in Cluster I, followed by cluster II (7), cluster III (5), cluster IV (5) and cluster V (4). Clusters VI and VII had one genotype each. Maximum divergence was shown between the Clusters II and VI, while the minimum divergence between clusters I and II. The intracluster distance was highest for the Cluster II. Among the 13 characters considered, life of spadix contributed maximum towards divergence followed by days to initiation of female phase. Grouping of genotypes into different clusters did not reflect the geographical origin of the varieties. Selection index analysis revealed that genotype Liver Red attained the maximum selection index value followed by PR x LR and PR x DT (1) and the minimum estimates were recorded for Rembolina, W x LJ and Corolix. The grouping of genotypes by selection indices followed almost the same pattern as their clustering pattern in the D2 analysis. Intervarietal hybridization was done to analyse the cross compatibility between 15 genotypes based on the percentage of candles bearing fruits, fruit set and seed germination. A total of 127 crosses were attempted based on the availability of receptive spadices and fresh pollen, out of which 80 were found to be successful. In almost all cross combinations the percentage of candles bearing fruits ranged from 50 to 100 per cent. Among the 15 genotypes, the maximum percentage of candles bearing berries was obtained for PR x OG (90.00 per cent) followed by AW (66.67 per cent) and PR x LR (65.00 per cent). The lowest value 5 per cent was obtained for Esmeralda and 11.11 per cent for Dragon’s Tongue. The number of fruits per candle ranged from 5 in Esmeralda x (PR x OG) to 85 in (PR x OG) x (OG x DT). The crosses LR x DT, (OG x DT) x (PR x OG), LR x FR and (PR x OG) x DT also recorded higher number of fruits per candle. The average number of fruits per candles was highest for Liver Red and lowest for Esmeralda. The percentage of fruit set was below 50 per cent for all the crosses. The lowest and highest percentage of fruit set was observed for Ceasor Violet and ‘Liver Red respectively. The berries obtained from different cross combinations took 4.5 to 7 months to mature. Most of the crosses had a high percentage of single seeded berries compared to double seeded berries except for the cross FR x LR. Among single seeded berries maximum seed size was for AW x (PR x OG). In a berry largest seed among the two seeded berries were observed for the crosses AW x (PR x OG) followed by [(PR x LR) x (PR x DT (2)]. The number of days taken for germination varied from four to nine days. The seeds obtained from most of the crosses showed germination except three crosses i.e., DT x LR, (KR x LR) x LJ and Esmeralda x (PR x OG) did not germinate at all. Percentage of germination was lowest in [PR x DT (2)] x LJ and highest in (PR x LR) x C. Seedlings of 57 out of 73 crosses that germinated survived for more than four months. The seedling survival percentage ranged from 38.46 per cent in LJ x (PR x OG) to 81.25 per cent in (KR x LR) x DT. The highest average survival was recorded by Liver Red and lowest was recorded for the genotype Lady Jane. Compatibility parameters estimated based on the performance of the fifteen genotypes as pollen parents. Highest percentage of candles bearing fruits was shown by PR x OG followed by Fla Red, Dragon’s Tongue and PR x LR. Lowest percentage were recorded for Flirt and KR x LR. Number of fruits per candle was the highest for the genotype PR x DT (2) followed by PR x OG, Dragon’s Tongue and Acropolis white. In Lady Jane, Flirt and KR x LR the number of fruits were relatively lower. Higher percentage fruit set was observed for the genotypes Dragon’s Tongue while it was lowest in Lady Jane. Percentage of seed germination was the highest for Fla Red and lowest for Lady Jane. Scoring of the compatibility reactions based on the percentage of fruiting candles, fruit set and seed germination on a scale ranging from zero to nine. After scoring the different genotypes, the crosses with highest compatibility score was for the crosses (PR x OG) x (OG x DT), (PR x LR) x C, FR x DT, AW x (PR x OG), (OG x DT) x (PR x OG), (PR x LR) x (PR x OG),PR x DT (2) x (PR x OG), (OG x DT) x LR, LJ x LR, (PR x OG) x DT, (PR x OG) x LR, (PR x OG) x (PR x LR) and (PR x LR) x FR. So these were the most compatible crosses. The performance of the variety as female parent was found to be different from its performance as male parent. The female parents PR x OG, PR x LR, Lady Jane, OG x DT and PR x DT (2) got the high varietal scores. Among male parents PR x OG, DT, OG x DT, FR and PR x LR got the high varietal scores. So PR x OG, OG x DT and PR x LR could be judged as the best male as well as female parents. Among the seedlings of the successful crosses maximum number of days for maturity of leaves was taken by the cross LJ x (PR x LR) and the least number of days was taken by C x (PR x OG). Number of leaves ranged from 4.50 in DT x FR to 6.33 in [(PR x OG) x (OG x DT)]. The leaf area was maximum for the cross LR x FR and it was minimum for LJ x (PR x OG). The colour of young leaf showed a range from brown to reddish brown to greenish brown to green. The colour of petiole also varied from brown to reddish brown to greenish brown to green.
