Mayadevi, Department of Plant Breeding and Genetics, College of AgriculturePravin, R SKAU2020-11-102020-11-102004172327https://krishikosh.egranth.ac.in/handle/1/5810154877MScThe 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.EnglishThesis