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Open Access
Heterosis breeding in sesame (Sesamum indicum L.).
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2011) Gayathri, G; KAU; Dijee, Bastian
The 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.
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, N
A 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.
Open Access
Invitro propagation in ashoka : saraca asoca (Roxb.) de wilde.
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2011) Brindha Devi, I; KAU; Sreenivasan, E
Asoka (Saraca asoca) is an important medicinal and ornamental tropical tree currently facing the threat of extinction due to overexploitation of trees occurring in forests and other natural habitats. Unscientific and destructive extraction of bark from trees has lead to acute shortage of raw bark by ayurvedic industries. Hence, 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. It is considered as the sacred tree of buddhists and Hindus. Literally the term ‘asoca’ means ‘sorrow-less’ and the tree is believed to remove the grief and unhappiness. The tree has immense medicinal properties. Its bark is considered as the primary medicinal part. 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. It is mainly propagated by seeds. Due to heterozygous and cross pollinated nature of the species, it never gives a true to type progeny. Therefore the present study was undertaken to standardize the technique of in vitro propagation of Saraca asoca. Standardization of suitable explants, surface sterilization procedures and culture establishment protocol, Induction of multiple shoots and Elongation of root, hardening and planting out are the major objectives of the study. Nodal segment, Internodal segment and shoot tip were the three explants tried. Various surface sterilization procedures were tried using Chloramphenicol, ethyl alcohol, 0.1% mercuric chloride and combination of ethyl alcohol and mercuric chloride in various concentration and duration, using nodal segments as explant. Surface sterilization using 70% ethyl alcohol for 3 minutes followed by 0.1% mercuric chloride for minutes proved to be the best, which gave the maximum survival percentage of 80. The next part of the study was standardisation of suitable explants for culture establishment. Among the three explants, Nodal segments gave maximum response of 60 per cent in ½ MS medium with BAP 0.5mg/l. This was followed by shoot tips in the same medium, which gave 10 per cent response. Internodal segments did not respond in any of the media used. Standardisation of basal media for culture establishment was done using nodal segments as the explants. Three media supplemented with BA 0.5 mg.l-1 were tried viz. MS, Half strenght MS, Woody plant media. Among the three, ½ MS media was identified as the best basal medium followed by MS medium. No response was seen in WPM medium. Culture establishment as well as Shoot bud initiation was attempted in ½ MS and MS media with various growth regulator combinations. Maximum response of 60 per cent was obtained in ½ MS medium containing BAP 0.5 mg/l followed by 30 percent in the same medium containing BAP 1.5 mg/l. There were no response with 2,4-D. The response obtained was callusing in all cases. Induction of multiple shooting was tried in ½ MS medium supplemented with BAP, and Kn alone as well as combinations of BAP, IAA at various concentration. Here highest response of 30 per cent of single shoots was recorded in ½ MS media containing BAP 0.5 mg/l. Response was in the form of single shoot. The single shoots with a mean length of about 1.5mm after one week of growth was obtained. With BAP 2.0 mg/l, single shoots were produced in about 5% of cultures within 54 days. Effect of Kn in various concentration ranging from 0.5 to 2.0 mg/l was found to be low in shoot induction. The maximum length of shoot of about 1.6 cm was recorded in combination of BAP 0.5 mg/l and IAA0.5 mg/l. Various combinations of IAA and IBA at different concentrations were tried for rooting of in vitro shoots. However there was no response in any of the combinations tried.
Open Access
G x E interaction in the F6 generation of wide crosses of rice (Oryza Sativa L.)
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2003) Vidhu Francis Palathingal; Kanakamani M T
The present study 'G x E interaction in the FG generation of wide crosses of rice (Oryza sativa L)' was carried out under the Department of Plant Breeding and Genetics, College of Horticulture, Kerala Agricultural University, Vellanikkara. The study was carried out for 20 characters in nine rice cultures at three locations viz., Mannuthy, Pattikkad and Adatt. The experiment estimated the variability, heritability, correlation, path coefficients and stability for the characters. High variability and heritability was noticed for most of the yield characters. The estimates of variability and heritability vaired widely between locations indicating the preponderance of the environment Correlation and direct and indirect effects of the characters on yield also differed between the environments indicating the profound influence oflocation on the character. Stability analysis revealed that among the rune nee cultures studied, culture C 26T(b) was found to be stable over locations for most of the yield traits. Culture C 26T(b) had maximum grain yield and was stable for most of the yield contributing characters like height of plant at harvest, number of productive tillers, number of spikelets per panicle, number of grains per panicle, number of days for physiological maturity, 1000 grain weigh! and grain yield. C 26T(b) showed superior and stable performance in the hill tracts of Pattikkad, Kole land of Adatt and at Mannuthy Stability parameters indicated C 80 as the next stable culture. C 80 was stable for the characters total number of tillers, days to 50 per cent flowering, hulling percentage, milling percentage and amylose content.
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, 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.
Open Access
Heterosis and combining ability in melon
(Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2000) Deepthy, R; KAU; Wilson, D
The 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.
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 R
Characterization 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:
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, I
A 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.
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 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.

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