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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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  • ThesisItemOpen Access
    Genetic analysis of F2 and F3 generations for yield attributes and resistances to distortion mosaic virus disease in bitter gourd (Momordica charantia L.)
    (Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2003) Sumarani, P; KAU; Arya, K
    The research project "Genetic analysis of F2 and F3 generations for yield attributes and resistance to distortion mosaic virus disease in bittergourd (Momordica charantia L.)" was carried out in Department of Plant Breeding and Genetics, College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur during the period 2002-2003. The major objectives of the study were to understand the genetics of yield attributes and resistance to bittergourd distortion mosaic virus (BDMV) and to identify resistant genotype with desirable yield traits. The whole investigation was grouped into two experiments in Randomised Block Design with three replication. The F2 and F3 generation of three selected crosses and parents were evaluated for yield attributes and resistance to BDMV. Significant variation was noticed for almost all characters except anthesis of male and female flowers. Highest phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were observed for BDMV followed by fruit yield and fruit weight in both generations. High heritability coupled with high genetic gain was noted for fruit weight, fruit yield and coefficient of infection. These characters are controlled mainly by additive genes which rendered scope for direct selection . . High yield was achieved by higher sex ratio, higher fruit weight, long fruit, optimum number of female flowers and low incidence ofBDMV. Based on the results from populations derived from the crosses IC68335 x Preethi and lC 68263B x Preethi as the best genotypes with high yield and resistance to bitter gourd distortion mosaic virus (BDMV) consecutively in both generations.
  • ThesisItemOpen Access
    Morphological, Biochemical and Molecular Markers for the Genetic Analysis of Cashew(Anacardium occidentale L.)
    (Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2003) Usha Vani, D; KAU; Jayalekshmy, V G
    The research project' Morphological, biochemical and molecular markers for the genetic analysis of cashew' was carried out in the College of Horticulture, Vellanikkara, Thrissur during the period 2000-2002. The major objectives of the study were to fingerprint cashew genotypes based on genetic analysis carried out and the genetic relationship deduced between the morphological, biochemical and molecular parameters studied and also to identify genetically diverse genotypes among those selected for the study to be used in breeding programmes. The study revealed that among the fourteen characters selected i.e., tree height, tree girth, number of primary branches, number of secondary branches, canopy spread, leaf area, number of panicles m", number of nuts m", number of perfect flowers m", apple weight, nut weight, kernel weight, shelling percentage and nut yield, all showed significant variation except number of primary branches. Number of perfect flowers m", number of nuts m", apple weight, nut weight and kernel weight provide a clear seperation of the genotypes. Correlation and path studies revealed tree height and number of nuts m" had significant positive correlation and direct effect on yield. Tree girth showed positive correlation but significant negative direct effect on yield. Number of primary branches showed significant positive direct effect but a significant negative correlation with yield. Apple weight showed significant negative correlation and significant negative direct effect with yield. Genetic divergence studied using Mahalanobis D2 analysis revealed H-1593 to be the most divergent genotype. Cluster' analysis could group them into four clusters. The members of Cluster I (Sulabha, Priyanka and P-3-2) and Cluster II (Mdk-L, AKM-l and K~22-1) were found to be best suited for hybrdisation being the farthest. Biochemical studies on phenol and tannin content could group the twelve genotypes into those with high and low .contents. The genotype H-1593 had the lowest phenol content. Seed storage protein studies could distinguish K-22-1 from all others by a single unique band. Isozyme analysis in cashew showed only high initial rate of reaction. Further studies to standardise the protocol for isozyme studies needs to be done. Molecular studies involved RAPD analysis using four primers which gave 44 amplification products out of which 30 (68.19 per cent) were found to be polymorphic. Two primers OPP-5 and OPP-IO could distinguish varieties Mdk-2 and Mdk-l with amplicons 22 and 25 respectively. Dendrogram constructed based on the study grouped together Kanaka and Dharasree; Mdk-l and Mdk-2 and H-1600 and P-3-2 with the latter two being the closest of all. On comparative study, H-1600 (Damodar) was tied to Dharasree in biochemical studies and with P-3-2 in molecular studies. In morphological studies also, it was placed close to P-3-2 indicating the proximity of Indian accessions with those of South America. Kanaka and Dharasree were tied together both in morphological and molecular studies but both were diverse by pedigree. Similarly, AKM-l and Dhana were placed close together in the three studies both of which were diverse by pedigree. H-1593 and H-1591 were found to be close in molecular and morphological studies. AKM-l and Mdk-l,Bapatla accessions and early flowering varieties, were closer in both morphological and molecular studies. It can be said that pedigree is not completely answerable to variability. The study had revealed a similar trend for morphological and molecular markers in deducing the genetic divergence. Biochemical markers need more refinement so as to get as precise information as has been obtained for the characterisation of the genotypes through molecular studies.
  • ThesisItemOpen Access
    Interspecific Hybridisation in Sorghum
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2005) Jithesh, V G; KAU; Suma Bai, D I
    A study on ‘Interspecific hybridization in Sorghum’ was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2003-2004 with the objective of developing sorghum-sudan grass hybrids with high fodder yield potential and better quality. Five superior accessions of sorghum viz., GD 65174-1,GD65174-2, GD 65195, GD 65239 and Acc. No. 846 (lines) with high yield potential and better palatability and three accessions of sudan grass viz., Jhansi local, SSG-59-3 and IS-720 (testers) with high tillering ability were crossed in a Line x Tester mating design to obtain 15 hybrid combinations. The lines, testers and their hybrids were evaluated along with a check COFS-29 in a replicated field trial for mean performance, combining ability and heterosis. Observations on plant height, tiller number per plant, stem girth, internodal length, leaf/stem ratio, leaf number per plant, leaf weight per plant, days to 50 per cent flowering, green fodder yield, dry fodder yield, crude protein content, crude fibre content and HCN content were recorded. Significant differences among treatments were observed for all characters. Significant differences among crosses were observed for all characters except tiller number per plant. General and specific combining ability variances and effects were studied. The magnitude of SCA variance alone was significant suggesting the predominance of dominance gene action in controlling these traits. Based on mean performance and gca effects, Acc. No. 846 was identified as the best general combiner among lines and SSG-59-3 among testers. The crosses, GD 65195 x IS-720 and Acc. No. 846 x SSG-59-3 were found to be promising for green fodder yield and its component traits based on mean performance, sca effects and standard heterosis. Hence these crosses can be advanced for further trials for developing superior sorghum-sudan grass hybrid varieties.
  • ThesisItemOpen Access
    Genetic improvement of F1 hybrids in anthurium andreanum linden
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2004) Pravin, R S; KAU; Mayadevi, Department of Plant Breeding and Genetics, College of Agriculture
    The present study, ‘Genetic improvement of F1 hybrids in Anthurium andreanum Linden’ was undertaken to improve specific commercial characters such as erect, long inflorescence axis, deep blisters of spathe and short downward candles of ten selected F1 hybrids in anthurium. The analysis of variance revealed significant variation among the fourteen genotypes for the seventeen 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 number of suckers per plant, pollen fertility and duration of male phase. The characters with high heritability coupled with high genetic advance values were found for characters number of suckers per plant, pollen fertility and pollen size. These characters are therefore controlled by additive gene action and amenable to genetic improvement through selection. Plant height was found to have highly significant positive phenotypic correlation with number of suckers per plant, leaf size, internode length, number of spadices per plant and pollen fertility. Duration of female phase showed positive genotypic correlation with all characters except days to initiation of female phase. The environmental correlations were absent for almost all pairs of characters except for a few characters . Pollen fertility estimated using acetocarmine method indicated that most of the genotypes had low fertility values. ‘PR x FR (1)’ had the highest pollen fertility of 41.67 per cent followed by ‘Liver Red’ (40.67 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 five 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. Intervarietal hybridization was done to analyse the cross compatibility between 14 varieties (Ten female parents and four commercially important varieties as male parents) based on the percentage of candles bearing fruits, fruit set and seed germination. A total of 23 crosses were attempted based on the availability of receptive spadices and fresh pollen, out of which 12 were found to be successful. Among the 12 successful crosses percentage of candles bearing fruits was 100 per cent for six crosses. Maximum number of 113 fruits was obtained for the cross (‘LR x PR’) x OG followed by [‘FR x MW (1)’] x LR with 88 fruits. The average number of fruits per candles was highest for ‘LR x PR’ and lowest for ‘PR x FR (1)’. 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 ‘PR x FR (1)’ and ‘LR x PR’ respectively. From the cross compatibility analysis, it was seen that the percentage of fruit bearing candles was highest for the female parents ‘PR x KR’ and ‘PR x MO’ with two crosses each and ‘OG x DT’ with a single cross (100 per cent). The number of fruit per candle ranged from 23 to 113. ‘LR x PR’ had the highest average number of fruits per candle and it was lowest for ‘PR x FR (1)’. The percentage of fruit set was below 50 per cent for all the crosses. The crosses involving ‘LR x PR’ had the highest average percentage of fruit set. The number of days taken for germination varied from four to nine days. The seed germination was highest for the cross (‘PR x FR(1)’) x LR (85.13 per cent). No cross showed 100 per cent survival beyond four to six months. For ‘OG x DT’ with only a single cross the survival percentage was maximum of 90 per cent. 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 showed the highest compatibility score of eight for the crosses (‘PR x KR’) x AW, (‘LR x PR’) x OG, (‘PR x MO’) x LR and (‘PR x MO’) x AW. Among the ten female parents ‘PR x MO’, ‘LR x PR’ and ‘PR x KR’ performed as the best female parents and among the four male parents ‘Liver Red’ performed as the best pollen parent.
  • ThesisItemOpen Access
    Compatibility studies of three way crosses in anthurium andreanum linden
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2003) Premna, Varghese; KAU; Mayadevi, P
    The evaluation of morphological characters and compatibility analysis of 14 selected genotypes was undertaken in the present study titled "Compatibility studies of three way crosses in Anthurium andreanum Linden. The analysis of variance revealed significant variation among the 14 genotypes for the 18 characters studied. This reveals genetic potential for crop improvement. Variability studies indicated high phenotypic, and genotypic coefficients of variation for the characters internode length, number of leaves and spadices per plant per year and days from emergence to maturity of leaves. The characters with high heritability coupled with high genetic advance values were leaf area, anthocyanin content and inclination of candle indicating additive gene action. Plant height was found to be positively correlated with number of leaves or spadices per plant per year. Candle length had positive genotypic correlation with position of candle. Pollen fertility ranged from 9.26 per cent in PR x DT to 35.70 per cent in Carre. Pollen emergence was completely absent in the genotype W x LJ during the course of the study. Pollen production was high in the r, cooler months of October to December and was suppressed in the months from March to June. From the cross compatibility analysis, it was seen that the percentage of fruit bearing candles was highest for W x LJ (100.00 %) with two crosses. The cross PR x LR with all the possible four crosses gave a value of 79.15 per cent. The number of fruits per candle ranged from 12 to 120. 00 x KR had the highest average number of fruits per candle and it was lowest for 00 x PR. The percentage of fruit set was below 50 per cent for all the crosses. The crosses involving 00 x KR had the highest average percentage of fruit set. The number of days taken for germination varied from four to nine days. The seed germination was highest (87.30 %) for the cross (00 x KR) x H. No cross showed 100 per cent survival beyond four to six months. For PR x LR with all the possible four crosses, the survival percentage was 56.80 per cent. 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 showed the highest compatibility score of nine for (00 x KR) x C. The best female parents identified were 00 x KR and PR x LR based on the overall performance.
  • ThesisItemOpen 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 V
    Asoka (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.
  • ThesisItemOpen 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, P
    The 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.
  • ThesisItemOpen Access
    Genetic analysis of yield and leaf curl virus resistance in chilli (Capsicum spp.)
    (Department of Plant Breeding, College of Agriculture, Vellayani, 2010) Anandhi, K; KAU; Abdul Khader, K M
    Pepper fruits (Capsicum spp.) are among the most consumed vegetables as fresh green or red and dried whole or ground forms in the world for its pungency. Leaf curl virus is an important biotic stress transmitted by the vector, Bemisia tabaci. Controlling the vector can be the only way to manage the disease and results in only partial control of disease. The incidence of disease is more in summer season and makes the cultivation uneconomical. There is an immediate need to develop leaf curl resistant varieties especially for summer cultivation. Hence the present investigation was undertaken at the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2007-2009 with the objective of estimating the combining ability, heterosis and gene action involved in the inheritance of yield and leaf curl virus resistance. Five resistant C. frutescens accessions Mangalapuram Local, Thavanur Local, Kayamkulam Local, Mavelikkara Local and Nenmara Local were crossed in L x T pattern with three high yielding susceptible varieties Jwalamukhi, Jwalasakhi and Vellayani Athulya and 15 F1s were produced and evaluated along with the parents in randomized block design. Analysis of variance revealed highly significant genotypic difference for all the characters studied. The observations recorded were plant height (cm), number of branches, number of days to first flowering, plant spread (cm), duration of flowering (fruiting span), number of fruits per plant, fruit length (cm), fruit width (cm), pedicel - fruit ratio, fruit colour at intermediate stage, green fruit yield per plant (g), average fruit weight (g), number of seeds per fruit, hundred seed weight (g), duration of crop, vector population and virus disease scoring. Higher estimates of PCV and GCV were recorded for vulnerability index and green fruit yield per plant. High heritability coupled with high genetic advance were exhibited for days to first flowering, duration of flowering, number of fruits per plant, green fruit yield per plant, number of seeds per fruit, duration of crop and vulnerability index. Combining ability analysis showed that the line Mavelikkara Local and Nenmara Local were alone good general combiners for fruit yield along with leaf curl resistance. Four hybrids viz., Mavelikkara Local x Jwalasakhi, Nenmara Local x Vellayani Athulya, Kayamkulam Local x Jwalamukhi and Thavanur Local x Jwalamukhi exhibited significant sca effect for fruit yield. Considering per se performance, standard heterosis and sca effect two hybrids Mavelikkara Local x Jwalasakhi and Nenmara Local x Vellayani Athulya were found to be superior. Generation mean analysis was carried out using six-parameter model. Six generations viz. P1, P2, F1, F2, B1, B2 were built up among the crosses Mavelikkara Local x Jwalasakhi and Nenmara Local x Vellayani Athulya. Presence of additive, dominance and epistatic interaction for all the characters indicated that hybridization or recombination-breeding programme can be followed for future breeding.
  • ThesisItemUnknown
    Intra and inter generic hybridization and molecular charatrization in monopodial orchids
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2008) Beena, Thomas; KAU; Lekha Rani, C
    A research programme entitled “Intra and inter generic hybridization and molecular characterization in monopodial orchids” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2005-2008 with the objective of undertaking intra and intergeneric hybridization, in vitro embryo culture and molecular characterization in monopodial orchids, as a preliminary step to develop novel hybrids. Fifteen monopodial orchid genotypes comprising of six genera viz., Aranda, Aranthera, Kagawara, Mokara, Renanthera and Vanda, with good cut flower qualities and high demand in the market were selected as parents after initial evaluation. They were evaluated adopting completely randomized design with five replications. Analysis of variance revealed significant differences for almost all the characters studied. Genotypic and phenotypic coefficients of variation were high for thickness of leaf, leaf area and number of aerial roots. High heritability (>70 %) combined with high genetic advance (>70 %) was observed for number of aerial roots, width of leaf, thickness of leaf, leaf area, number of spikes per shoot and number of flowers per inflorescence. Significant positive inter-correlation at genotypic and phenotypic levels was observed for length of flower and width of flower with number of spikes per shoot. The character number of spikes per shoot recorded significant positive correlation with leaf area. Number of flowers per inflorescence was positively correlated with number of leaves per shoot and length of inflorescence. Out of the six genera studied, four viz., Aranda, Aranthera, Kagawara and Mokara, exhibited free-flowering nature. Seasonal flowering was observed mainly from June to December in Vanda, whereas it was confined to two seasons, from February to March and August to October in Renanthera. Inflorescence axis was found to be arching in Aranthera and Renanthera while the rest of the genotypes produced erect inflorescence axis. The 15 parental genotypes were crossed in all possible combinations after preliminary studies on floral biology. A total of 225 cross combinations were attempted including 105 crosses, 105 reciprocals and 15 selfs. Incompatibility reactions were noticed at different stages ranging from flower abscission before the onset of any visible post pollination change to instances where seeds germinated but aborted in culture. Mature green capsules were harvested from 70 combinations at 70 to 90 per cent maturity. Among them 15 combinations did not yield any seeds in the capsule while the remaining 55 combinations were cultured axenically. Among the 55 combinations inoculated in vitro, no germination was obtained from seeds of 12 combinations. Out of the 43 combinations that germinated successfully, seven combinations showed arrested development. Thus out of the total 55 combinations inoculated in vitro 36 combinations developed successfully. These were subcultured three to four times. Seedlings having 2-3 leaves and 2-3 roots were deflasked and planted out. MS half strength was selected as the best basal medium. For improving the in vitro growth of hybrid monopodial orchid seedlings refinement of this medium by supplementing with IAA (8 mg l-1) and NAA (2 mg l-1) was beneficial. Significant differences among the combinations were observed with respect to number of days taken for germination initiation, number of days taken for development of protocorms, chlorophyll, first leaf, first shoot and first root primordia and for deflasking. Significant differences in seedling morphology were observed among the 36 hybrid combinations at deflasking. These were kept in humidity chamber for acclimatization for one month, transferred to net house for hardening and maintained there for further growth. In the present study, RAPD was employed for studying the genetic diversity and for the fingerprinting of 20 monopodial orchid hybrids, making use of arbitrary primers to amplify random DNA sequences in the genome. To identify the promising primers for RAPD analysis, 70 decamer primers of kit A, B, C and D were screened using the DNA of hybrid H-2. Based on the performance in DNA amplification, eight decamer primers were identified for RAPD analysis. Primers that produced highest number of polymorphic bands which were intense and reproducible were selected. They were OPB-07, OPB-15, OPB-l7, OPC-04, OPC-05, OPC-08, OPC-15 and OPD-02. a total of 57 scorable bands (average of 7.125 bands per primer) were generated by the selected eight primers of which six were monomorphic and the remaining 51 were polymorphic (89.47%). The estimation of Jaccard’s coefficients and construction of dendrogram by using UPGMA revealed the presence and extent of genetic similarities among the 20 monopodial orchid hybrids. The overall similarity coefficients ranged from 0.40 to 0.84. Cluster analysis revealed that at 0.69 similarity coefficient, the 20 monopodial orchid hybrids got divided into six groups. Among the 20 hybrids, H-18, H-7, H-13, H-17, H-19 and H-20 stood separately in clusters II, III A, III B, IV, V and cluster VI respectively. This substantiates the moderately broad distribution of genetic variability, which can be attributed to the broad genetic base in their ancestry. Cluster I A contained four hybrids viz., H-1, H-10, H-3 and H-9. This grouping is justified by the presence of a common parent i.e., Arachnis Maggie Oei Red Ribbon in their parentage. Moreover, two common species viz., Arachnis hookeriana and Arachnis flos-aeris are involved in their ancestry. All these support their belonging to the same cluster. The three hybrids such as H-5, H-6 and H-8 fell in cluster I B. RAPD technique is relatively simpler, quicker, less expensive and non-radioactive than other molecular characterization techniques. The results of present investigation proved that it can detect sufficient polymorphisms in genetic distance studies in monopodial orchids. A research programme entitled “Intra and inter generic hybridization and molecular characterization in monopodial orchids” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2005-2008 with the objective of undertaking intra and intergeneric hybridization, in vitro embryo culture and molecular characterization in monopodial orchids, as a preliminary step to develop novel hybrids. Fifteen monopodial orchid genotypes comprising of six genera viz., Aranda, Aranthera, Kagawara, Mokara, Renanthera and Vanda, with good cut flower qualities and high demand in the market were selected as parents after initial evaluation. They were evaluated adopting completely randomized design with five replications. Analysis of variance revealed significant differences for almost all the characters studied. Genotypic and phenotypic coefficients of variation were high for thickness of leaf, leaf area and number of aerial roots. High heritability (>70 %) combined with high genetic advance (>70 %) was observed for number of aerial roots, width of leaf, thickness of leaf, leaf area, number of spikes per shoot and number of flowers per inflorescence. Significant positive inter-correlation at genotypic and phenotypic levels was observed for length of flower and width of flower with number of spikes per shoot. The character number of spikes per shoot recorded significant positive correlation with leaf area. Number of flowers per inflorescence was positively correlated with number of leaves per shoot and length of inflorescence. Out of the six genera studied, four viz., Aranda, Aranthera, Kagawara and Mokara, exhibited free-flowering nature. Seasonal flowering was observed mainly from June to December in Vanda, whereas it was confined to two seasons, from February to March and August to October in Renanthera. Inflorescence axis was found to be arching in Aranthera and Renanthera while the rest of the genotypes produced erect inflorescence axis. The 15 parental genotypes were crossed in all possible combinations after preliminary studies on floral biology. A total of 225 cross combinations were attempted including 105 crosses, 105 reciprocals and 15 selfs. Incompatibility reactions were noticed at different stages ranging from flower abscission before the onset of any visible post pollination change to instances where seeds germinated but aborted in culture. Mature green capsules were harvested from 70 combinations at 70 to 90 per cent maturity. Among them 15 combinations did not yield any seeds in the capsule while the remaining 55 combinations were cultured axenically. Among the 55 combinations inoculated in vitro, no germination was obtained from seeds of 12 combinations. Out of the 43 combinations that germinated successfully, seven combinations showed arrested development. Thus out of the total 55 combinations inoculated in vitro 36 combinations developed successfully. These were subcultured three to four times. Seedlings having 2-3 leaves and 2-3 roots were deflasked and planted out. MS half strength was selected as the best basal medium. For improving the in vitro growth of hybrid monopodial orchid seedlings refinement of this medium by supplementing with IAA (8 mg l-1) and NAA (2 mg l-1) was beneficial. Significant differences among the combinations were observed with respect to number of days taken for germination initiation, number of days taken for development of protocorms, chlorophyll, first leaf, first shoot and first root primordia and for deflasking. Significant differences in seedling morphology were observed among the 36 hybrid combinations at deflasking. These were kept in humidity chamber for acclimatization for one month, transferred to net house for hardening and maintained there for further growth. In the present study, RAPD was employed for studying the genetic diversity and for the fingerprinting of 20 monopodial orchid hybrids, making use of arbitrary primers to amplify random DNA sequences in the genome. To identify the promising primers for RAPD analysis, 70 decamer primers of kit A, B, C and D were screened using the DNA of hybrid H-2. Based on the performance in DNA amplification, eight decamer primers were identified for RAPD analysis. Primers that produced highest number of polymorphic bands which were intense and reproducible were selected. They were OPB-07, OPB-15, OPB-l7, OPC-04, OPC-05, OPC-08, OPC-15 and OPD-02. a total of 57 scorable bands (average of 7.125 bands per primer) were generated by the selected eight primers of which six were monomorphic and the remaining 51 were polymorphic (89.47%). The estimation of Jaccard’s coefficients and construction of dendrogram by using UPGMA revealed the presence and extent of genetic similarities among the 20 monopodial orchid hybrids. The overall similarity coefficients ranged from 0.40 to 0.84. Cluster analysis revealed that at 0.69 similarity coefficient, the 20 monopodial orchid hybrids got divided into six groups. Among the 20 hybrids, H-18, H-7, H-13, H-17, H-19 and H-20 stood separately in clusters II, III A, III B, IV, V and cluster VI respectively. This substantiates the moderately broad distribution of genetic variability, which can be attributed to the broad genetic base in their ancestry. Cluster I A contained four hybrids viz., H-1, H-10, H-3 and H-9. This grouping is justified by the presence of a common parent i.e., Arachnis Maggie Oei Red Ribbon in their parentage. Moreover, two common species viz., Arachnis hookeriana and Arachnis flos-aeris are involved in their ancestry. All these support their belonging to the same cluster. The three hybrids such as H-5, H-6 and H-8 fell in cluster I B. RAPD technique is relatively simpler, quicker, less expensive and non-radioactive than other molecular characterization techniques. The results of present investigation proved that it can detect sufficient polymorphisms in genetic distance studies in monopodial orchids.