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ThesisItem Open Access Genetic evaluation of F2 generation of intervarietal crosses in greengram (vigna radiata (L.) wilczek(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2001) Leenamol, M A; KAU; Kamalam, NA research programme was carried out at the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2000-2001 with the objective of assessing the potential of F2 progenies of greengram in terms of variability and correlation with respect to yield, yield attributes and shade tolerance. Fifteen F 2 progenies derived from intervarietal crosses were evaluated under the partial shade of coconut garden adopting a randomised block design with three replications. Data collected for seventeen characters were subjected to statistical analysis. Coefficient of variation, heritability, genetic advance, correlation and path coefficients were estimated. The 15 F 2 progenies revealed significant difference for all the characters. However, measurement of periodical shade intensity did not show significant difference among the plots indicating the prevalence of uniform shade. Phenotypic and genotypic coefficient of variation were high for grain yield, leaf area index, number of pods per plant, photosynthetic efficiency, harvest index and 100 seed weight. High heritability coupled with high genetic advance was observed for harvest index, grain yield, number of pods per plant, 100 seed weight and photosynthetic efficiency. Correlation studies indicated that the characters leaf area index, . photosynthetic efficiency, number of seeds per pod, 100 seed weight and harvest index exhibited significant positive correlation with grain yield whereas days to 50 per cent flowering and days to maturity recorded significant negative correlation. Among yield components, photosynthetic efficiency and harvest index exhibited significant positive correlation with number of seeds per pod and 100 seed weight. Photosynthetic efficiency exhibited the highest positive direct effect on grain yield followed by harvest index. Negative direct effect on grain yield was recorded for number of seeds per pod, days to maturity and days to 50 per cent flowering. It can be concluded from the present study that under partially shaded condition, photosynthetic efficiency and harvest index are the most important yield components which can serve as selection criteria for better yield in greengram. Accordingly the genotypes T 7 (Ganga 4 x Pusa Baisakhi), T 5 (LGG 460 x Philippines), T I (IIPRM 3 x Philippines), T 2 (Ganga 4 x Philippines) and TI4 (RMG 353 x CO-2) and Tlo (LGG 460 x Pusa Baisakhi) may be selected for further work.ThesisItem Open 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, KThe 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.ThesisItem Open Access Heterosis and combining ability in melon(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2000) Deepthy, R; KAU; Wilson, DThe current research programme on 'Heterosis and combining ability in melon (Cucumis melo (L.) var. conomon) was carried at the Department of Plant Breeding and Genetics, College of Agriculture, VeIl ay ani during 1998- 2000. The objectives were estimation of various genetic parameters, heterosis and combining ability effects of parents and hybrids. The experimental material consisted of seven parents and their 21 F 1 hybrids (without reciprocals). Analysis of variance revealed highly significant difference among the genotypes for all the 21 characters studied. The genotype P3 topped in mean performance for yield and many yield attributes. The hybrids P2 x P6 and P2 x P3 were superior in yield and fruit characters, whereas P6 x P7 was the best for keeping quality, yield and crop duration. Genetic parameters like PCV, GCV, heritability and genetic advance were high for keeping quality, yield, sex ratio and mean fruit weight. Environmental component of variation was negligible for majority of traits. Significant heterosis was observed for all the characters studied. P3 x P 4 showed maximum standard heterosis for yield whereas, P2 x P 6 showed maximum relative heterosis and fruit characters and earliness traits. Variance due to GCA and SCA were significant for all the traits studied. P3 was the best general combiner for yield, fruit diameter, mean fruit weight and fruit length and P2 was the best for node characters and crop duration. The hybrid P6 x P7 was the best specific combiner for yield. Combining the mean performance, SCA effects and standard heterosis, P2 x P6 was identified as the superior cross in terms of yield and yield attributes whereas P 4 x Ps was the best for various flowering traits.ThesisItem Open Access Characterisation and evaluation of the rice cultivar njavara(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2000) Srinivasa Reddy, G; KAU; Elsy, C RCharacterization and evaluation of the rice (Oryza saliva L.) cultivar Njavara was undertaken in the Department of Plant Breeding and Genetics and Biochemistry Laboratory, College of Horticulture, Vellanikkara during 1997-1999 with an aim to characterize Njavara genotypes based on morphological and biochemical studies and to evaluate its nutritional qualities. Morphological characterization indicated that the thirteen Njavara genotypes were distinct among themselves and the Njavara genotypes NI (Njavara type from Mulloorkara, Thrissur), N2 (Njavara type from Chittoor, Palakkad), N5 (Njavara type from Edavanna, Malappuram), NIl (Njavara type from Pattambi, Palakkad) and NI3 (Njavara type from Thootha, Palakkad) yielded on par with the check variety Ptb-IO, eventhough they were having extra short growth duration compared to Ptb-I 0. Biochemical characterization revealed the possibility of utilizing peroxidase, esterase and protein polymorphism for identifying the Njavara genotypes especially NI (Njavara type from Mulloorkara, Thrissur) , N2 (Njavara type from Chittoor, Palakkad), N3 (Njavara type from Chittoor, Palakkad) and N4 (Njavara type from Chittoor, Palakkad) and also for the identification of Njavara as a cultivar. Selecting some other isozymes coupled with enzyme activity studies and opting for molecular markers were the other strategies suggested for characterization of Njavara genotypes. Majority of the Njavara genotypes expressed high protein content than Ptb-l O. The genotypes N2 (Njavara type from Chittoor, Palakkad) and N8 (Njavara type from Alwaye) were recommended to be included in weaning and invalid foods due to high protein content. The genotypes N2 (Njavara type from Chittoor, Palakkad), N3 (Njavara type from Chittoor, Palakkad) and NI2 (Njavara type from Thrissur) appeared to have higher number and content of free amino acids. Most of the Njavara genotypes had intermediate amylose and as such may not have any problem with respect to consumer preference. Starch grain characterization revealed that starch grain size could be used for varietal characterization in conjunction with morphological and biochemical markers. Absence of flavonoids in Nj avara grain indicated its nonaromatic nature. The genotype N7 (Njavara type from Tellicherry, Kannur) was found to have better digestibility due to low amylose content, high amylase activity and high soluble carbohydrate content. Variability studies indicated that fat content, straw yield and grain yield provided a good genetic base for selection. Correlation and path studies revealed that grain yield could be improved by simultaneous selection for high straw yield and longer leaves while selection for wider leaves, longer ligules, increased number of days to 50 per cent heading, longer panicles and long duration genotypes favour high free amino acid content. Low amylase activity, short and narrow leaves, shorter panicles, low 1000 grain weight, slender grains, short duration genotypes and smaller starch grains were observed to favour high protein content and selection for tall culms, high 1000 grain weight and bold grains was found to favour high amylase activity:ThesisItem Open Access Heterosis and gene action in bajra - napier hybrids(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2002) Serene Das, M; KAU; Suma Bai, IA study on 'Heterosis and gene action in bajra-napier hybrids' was carried out with the objective of developing bajra-napier hybrids with high yield potential and good quality. The study was undertaken during the year 2001-2002 in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani. Seven lines of bajra, viz., APFB-2, Composite 9, DRSB-3, FD 1917, HES-4, IP 15814 and TNSC-4 and three testers of napier grass, FD 431, FD 467 and FD 471 were crossed in a line x tester mating design to obtain 21 cross combinations. The hybrids were evaluated along with their parents for mean performance, combining ability, heterosis and gene action for eleven yield and yield related characters. Significant differences among treatments were observed for all the characters. Also significant differences among parents and crosses were observed for these characters and their general and specific combining ability variances and effects were studied. The magnitude of SCA variances alone was significant suggesting the predominance of non-additive gene action in controlling these traits. Based on mean performance and gea effects, HES-4 was identified as the best general combiner among lines followed by TNSC-4. Among testers, FD 467 can be selected as the best male parent followed by FD 471. The crosses, TNSC-4 x FD 471 and HES-4 x FD 467 were the promising combinations for green fodder yield and its component traits, based on mean performance, sea effects and standard heterosis. Hence these crosses can be exploited for developing high yielding hybrids.ThesisItem Open 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 GThe 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.ThesisItem Open 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 AgricultureThe 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.ThesisItem Open 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, PThe 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.ThesisItem Open Access Genetic and physiological analysis of ratooning in rice(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2000) Ambili Nair, S; KAU; Rosamma, C AThe present investigation 'Genetic and physiological analysis of ratooning in rice (Oryza sativa L.)' was conducted at the Agricultural Research Station, Mannuthy during 1999-2000 to study the main crop as well as ratoon crop behaviour of different rice genotypes. The study was carried out to determine genetic variability among the different genotypes used. The study was also aimed at identifying morphological and physiological characters for a genotype of rice with high productivity when main and ratoon crop yields are combined together, through correlation and character association studies. Suitable selection indices were also formulated for identifying superior genotypes. Among the 50 genotypes evaluated in the main crop 24 showed regrowing ability. Of these five varieties viz. CO 43, IR 20, White Ponni, Ponmani and Mangala Mahsuri recorded better ratoon performance. The ratoon crop characters were less pronounced compared to the main crop characters except chlorophyll contents. But the above mentioned genotypes 'exhibited a higher intensity of character expression in both crops compared to the remaining genotypes. The estimates of GCV, heritability and genetic gain were high in the caseofratoon crop for most of the characters studied. Present study revealed that higher total yield can be achieved with a main crop having long duration and increased number of unproductive tillers plant". Ratoon yield can be improved by a better performing main crop with characters such as long duration, more number of grains panicle", more number of unproductive tillers plant" and reduced grain production day". Ratooning ability was considered as an index of the ratoon performance but in the present study ratooning ability recorded a negative direct effect on yield, indicating that this cannot be used as a true index to assess the ratoon performance. The various genetic and physiological analysis thus revealed that the varieties viz. IR 20, Mangala Mahsuri, White Ponni and Ponmani can be recommended as genotypes suitable for ratooning in Kerala. By using these about one third of the main crop yield can be achieved without increasing the land area. Total yield recorded 1;>y these genotypes were also significantly high.
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