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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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201815
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Subject: Plant Breeding × End date: 2018 × Start date: 2018 ×
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Now showing 1 - 9 of 15
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    ThesisItemOpen Access
    Evaluation of CMS based rice hybrids developed from rice varieties of Kerala identified as restorers
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2018) Nayana Jyothibas, KAU; Jayalekshmy, V G
    The present study entitled “Evaluation of CMS based rice hybrids developed from rice varieties of Kerala identified as restorers” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2016-2018, with an objective to evaluate CMS based rice hybrids developed from rice varieties of Kerala as restorers, for heterosis for yield and grain quality. The study was conducted in two experiments i.e., 1) Hybrid seed production 2) Evaluation of hybrids. The first experiment, on hybrid seed production was undertaken in College of Agriculture, Vellayani during May to August, 2017 (Virippu, 2017). Two CMS lines viz., CRMS31A and CRMS32A were crossed with nine restorers. Restorers were sown in three staggers, 10 days before the sowing date of CMS lines, at the sowing date of CMS lines and 10 days after the sowing date of CMS lines. Synchronized flowering dates of the CMS and restorer lines were recorded. CRMS31A was crossed with Remya, Jayathy, Swarnaprabha, Kanakom and Neeraja. CRMS32A was crossed with Annapoorna, Aiswarya, Mattatriveni and Kanakom. Six crosses i.e., CRMS31A x Jayathi (H1), CRMS31A x Kanakom (H2), CRMS31A x Remya (H3), CRMS32A x Annapoorna (H4), CRMS32A x Kanakom (H5), CRMS32A x Mattatriveni (H6) that had given more than 1500 viable seeds were carried forward for hybrid evaluation. Date of sowing of the restorers and maintainers for getting synchronization in flowering to undertake hybridization was standardized in this experiment. In the second experiment, hybrids along with the better parent and checks were evaluated in a Randomized Block Design (RBD) with three replications during October 2017 to February 2018 (Mundakan) in IFSRS (Integrated Farming System Research Station), Karamana. Observations on 12 yield contributing traits and 8 grain quality traits were recorded in the hybrids. Genetic parameters calculated from these observations showed that the GCV and PCV values for the characters studied did not vary greatly indicating low influence of the environment in these characters. The mean performance of hybrids showed that the yield plot -1 was the highest for H5 (CRMS32A x Kanakom) followed by H3 (CRMS31A x Remya), H1 (CRMS31A x Jayathi), H2 (CRMS31A x Kanakom) and H4 (CRMS32A x Annapoorna). The hybrid H5 (CRMS32A x Kanakom) showed the highest mean values for plant height, number of filled grains panicle-1, length breadth ratio of grain and grain yield (g) plant-1. Pollen fertility of the hybrid H3 (CRMS31A x Remya) was superior to the standard check. This shows that the variety Remya is a complete restorer for male sterile cytoplasm CRMS31A. Hybrid H5 also showed pollen fertility on par with the check showing that the variety Kanakom is restorer for CRMS32A. The other hybrids H4 (CRMS32A x Annapoorna) and H6 (CRMS32A x Mattatriveni) had pollen fertility per cent around 50. So the male parents Annapoorna and Mattatriveni for CRMS32A can be considered as only partial restorers. The low level of pollen fertility was the reason for low yield of hybrids H4 (CRMS32A x Annapoorna) and H6 (CRMS32A x Mattatriveni) despite high number of productive tillers. Five out of six hybrids were red kernelled. It was found that the hybrids inherited the kernel colour from the male parents. The kernel length by breadth ratio of all the hybrids was significantly higher than that of Uma. The hybrids had a medium to slender grain shape (kernel length by breadth ratio 2.1 to 3 and above). This may be the reason behind the phenomenon of curling noted in cooked rice in all the rice hybrids studied. Standard heterosis for yield plot-1of the hybrids calculated over the standard check variety Uma was the highest for H5 (CRMS32A x Kanakom) followed by H3 (CRMS31A x Remya) and H1 (CRMS31A x Jayathi). Heterobeltiosis for yield calculated over the better parent was maximum for H1 (CRMS31A x Jayathi) followed by H5 (CRMS32A x Kanakom). Amylose content of most of the hybrids fell into intermediate category along with that of the check variety Uma, showing the hard and non sticky nature of the cooked rice of the hybrids. Cooking time for hybrids was less compared to that of Uma (29 minutes). This evaluation of hybrids could identify two promising hybrids for Kerala H5 (CRMS32A x Kanakom) and H3 (CRMS31A x Remya) which could give a yield advantage of 17.91% and 16.37% over the popular rice variety Uma. These two hybrids had long slender grain shape with red kernel colour. The amylose content of these two hybrids was also intermediate and low. These hybrids had a lower cooking time and good head rice recovery. Hence the hybrids can be recommended for Kerala after trials over locations and seasons. A better seed production technique has to be standardized before commercial release.
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    ThesisItemOpen Access
    Identification of water stress tolerant amaranthus genotypes (Amaranthus tricolor L.) with high yield and quality
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2018) Shahiba, A M; KAU; Beena Thomas
    The present study entitled “Identification of water stress tolerant amaranthus genotypes (Amaranthus tricolor L.) with high yield and quality” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2016-2018, with an objective to identify high yielding genotypes of amaranthus with good quality and tolerance to water stress. The study was conducted under two experiments. In the first experiment thirty accessions of Amaranthus tricolor L. available in the Department of Plant Breeding and Genetics and collected from other sources were evaluated for yield under field condition and morphologically described using IBPGR descriptor for the amaranthus. Madhur local (A22) recorded highest yield plant-1(125.926g) followed by Kalliyoor local (A4), Ayyanthole local (A28), Haripad local (A7), Palakkadu local (A2), Anachal local (A6), Aryanadu local (A21), Poonkulam local (A20), Kazhakkuttom local (A9) and Kannara local (A29). In the second experiment, these ten genotypes selected based on the yield were evaluated in a Randomized Block Design (RBD) with three replications during November 2017- December 2017. Water stress was imposed after 5 days of irrigation to water holding capacity to the transplanted seedlings by scheduling the irrigation at a depth of 20mm at 20mm CPE (Cumulative Pan Evaporation). Analysis of variance was calculated for all the characters under study and was found to be significant for all the genotypes evaluated. The mean performance of the genotypes for the characters were studied. The maximum yield was observed for the genotype A22 (Madhur local) followed by the genotype A9 (Kazhakkuttom local), genotype A20 (Poonkulam local) and genotype A2 (Palakkadu local) and the minimum yield was recorded for genotype A4 (Kalliyoor local). The genotype A22 (Madhur local) showed the highest mean values for stem girth, number of branches, length of leaf lamina, leaf to stem ratio, membrane integrity, relative water content, proline content of leaves, vitamin A and lowest oxalate content. The character Vitamin A content registered the highest GCV (41.22%) and PCV (41.25%). High heritability coupled with high genetic advance was observed for leaf width, number of branches, yield plant-1, protein content, fibre content and vitamin A. The yield plant-1was found to be significantly and positively correlated with leaf width, number of branches, yield plot-1, membrane integrity, proline content of leaves and vitamin A both at genotypic and phenotypic levels. Petiole length and percentage leachate were found to be negatively correlated with yield plant-1. Path analysis revealed that number of branches, yield plot-1and proline content of leaves had the maximum positive direct effect on yield plant-1. The results of the present study showed that genotype A22 (Madhur local) was superior in yield performance under water stress condition followed by the genotype A9 (Kazhakkuttom local), genotype A20 (Poonkulam local) and the genotype A2 (Palakkadu local). The genotype A22 (Madhur local) also recorded the maximum stem girth, number of branches, length of leaf lamina, leaf to stem ratio, membrane integrity, relative water content and proline content of leaves with high Vitamin A and low oxalate content. Presence of proline in the leaves might be considered as an important water stress tolerance mechanism.
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    ThesisItemOpen Access
    Identification of saline tolerant rice hybrids for pokkali tract
    (Department of Plant Breeding and Genetics, Vellanikkara, 2018) Nikhil Narayanan; Biju, S
    Various abiotic stresses causing a decline in global rice production are drought, salinity and chillness. Among these, salinity is the major factor that affects crop productivity. The traditional rice varieties grown under Pokkali area show remarkable tolerance to salinity and floods making it unique. However, the yield potential of these varieties is low. In India, out of ninety three rice hybrids developed, a few viz. DRRH 28, KRH 4, PSD 3, etc. were reported to have tolerance to salinity. Considering the potentials of hybrids, identification of salt tolerant hybrids suitable for Pokkali tract of Kerala is an urgent need of the hour. Hence, the study was designed to explore the adaptability of eight rice hybrids to the unique tract of Pokkali and evaluation of traits associated with salinity tolerance. The study comprised of two experiments, the first experiment was Laboratory screening for salinity tolerance and the second experiment was Field evaluation of rice hybrids in Pokkali tract. The laboratory screening was done following a completely randomised design and the genotypes were grown in Yoshida's solution and evaluated for various seedling characters. High shoot length, root length, high root CEC and high root and shoot proline content were seen in Vytilla-6 followed by Ezhome-2. Low root and shoot proline content were observed in IR-29 confirming its susceptibility to salinity. Among the hybrids, a high value for shoot length, root length, total number of roots, root CEC, root proline, shoot proline and survival per cent was observed in the hybrids CORH-3 and KRH-4. Vigour index was high in Sahyadri 4 followed by KRH-4 and low in MRP- 5401. Vytilla-6 and Ezhome-2 showed the high survival per cent while low survival per cent was noticed in Sahyadri 2 and MRP-5401. Vytilla-6 exhibited high chlorophyll content and RWC while low RWC was recorded in MRP-5401, Sahyadri- 2 and Sahyadri-4. Ca in root and shoot along with Na content in shoot were high in IR-29 while Vytilla-6 had low Ca and Na content. High Na in root was seen in Sahyadri 4 followed by Sahyadri 3. High amount of root Cl2 was recorded in Sahyadri-3, Sahyadri-1, Sahyadri-4, IR-29 and Sahyadri-2 while, the lowest amount of root and shoot Cl2 was in Vytilla-6. High amount of shoot Cl2 was seen in Ezhome-2 and IR-29. High amount of root and shoot SO4 content was seen in IR-29, Sahyadri-3, Sahyadri-4, Sahyadri-2 and Sahyadri-1. The lowest root and shoot SO4 content was recorded in Ezhome-2, followed by Vytilla-6. Low visual score of 3 was recorded in Vytilla-6 and Ezhome-2; a score of 5 was recorded for CORH-3, MRP-5401, TNAU RH-4 and KRH-4. Sahyadri-2, Sahyadri-3 and Sahyadri-4 were observed to have scored more than seven. Score 9 was noticed in Sahyadri-1 and IR-29, indicating that these genotypes are more susceptible to salinity. Visual score under salinity was found to be negatively correlated with shoot and root length, number of roots, vigour, proline content and RWC, while it was positively correlated with content of Ca, Na, Cl2, SO4 and K in the plant tissue. Field evaluation of rice hybrids in Pokkali tract was done during Kharif season of 2016-17, following a randomised block design. Days to fifty per cent flowering and maturity showed that all hybrids became early under salinity. Tall plants were observed in Vyttila-6 and Ezhome-2 and short plants in IR-29. High number of productive tillers was observed in CORH-3 and low in Sahyadri-2. Ezhome-2, IR-29 and Vyttila-6 had high number of spikelets per panicle while seed setting percentage and long panicles were observed in Ezhome-2. Spikelet sterility was high in Sahyadri-2 and low Ezhome-2. High 1000 grain weight was observed in Ezhome-2 and low in IR-29. Based on visual scoring Vyttila-6 was classified as highly tolerant and IR-29 as highly susceptible. Correlation studies indicated that grain yield per plant was positively correlated with productive tillers per plant and seed setting per cent, while it was found to be negatively correlated with sterility per cent. Visual scoring was negatively correlated with plant height, uppermost internodal length, days to maturity and seed setting per cent. The hybrid CORH-3 was found to be moderately tolerant based on visual scoring and it produced highest yield per plant indicating that this hybrid is better than saline tolerant traditional varieties.
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    ThesisItemOpen Access
    Breeding cowpea (Vigna unguiculata (L.) Walp.) for resistance to spotted pod borer (Maruca vitrata Fab.)
    (Department of Plant Breeding and Genetics, Vellanikkara, 2018) Ambavane Ajinkya Rajendra; KAU; Jiji Joseph
    Cowpea [Vigna unguiculata (L.) Walp.] is important pulse crop rich in nutrients, especially proteins. This crop is cultivated in the tropics of Asia, Africa and other parts of the world. Nevertheless, the production of cowpea is unable to achieve its summit. One of the prime reasons for this is the infestation of a notorious pest, the spotted pod borer, (Maruca vitrata Fab.; Lepidoptera: Crambidae). Spotted pod borer is one of the most important post-flowering pests of cowpea in the tropics. It is a major lepidopteran pest and damage cause to cowpea by the pest almost always crosses economic threshold level. Hence, the present investigation was conducted in the Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, Kerala Agricultural University, Thrissur during 2015 to 2018 with the objective of identification and incorporation of resistance against spotted pod borer in high yielding varieties of cowpea and assessment of parental polymorphism at the molecular level Thirty genotypes of cowpea formed the material for the study. These genotypes were subjected to field screening against spotted pod borer. These genotypes were also evaluated for morphological and biochemical basis of resistance. Five selected genotypes from experiment 1 then hybridised with four high yielding genotypes viz., Geethika, Vellayani Jyothika, Lola and Kashi Kanchan following Line × Tester mating design. Twenty F 1 hybrids evaluated for field resistance and the morphological basis of resistance. Progenies of selected F 1 hybrids grown as F 2 populations and evaluated for same parameters as like F 1 s. Thirty genotypes were also subjected to molecular screening by 40 SSR primers. Wide variation was observed in terms of different damage parameters. Ten genotypes viz., Hridya, Palakkadan thandan payar, EC 300039, EC 98668, EC 101216, IC 52110, IC 39945, IC 2918, IC 39922 and IC 39916 recorded total damage below five per cent. Among them, IC 39922 observed to have no flower bud and flower damage, EC 300039, EC 98668, IC 52110, IC 39945, IC 2918 and IC 39916 recorded no flower damage, whereas, Palakkadan thandan payar, IC 39945, IC 2918 and IC 39947 were free from pod damage. The highest damage was recorded in the variety Bhagyalakshmy (48.46 %) followed by variety Lola (30.04 %). Analysis of the morphological basis of resistance to spotted pod borer revealed the negative correlation of trichome density and length on flower bud, trichome density on the pod and pod wall thickness with respective damage parameters. With respect to the biochemical basis of resistance to spotted pod borer, total sugar content, reducing sugar content and non-reducing sugar content of flower bud and pod showed a positive correlation with damage parameters, but the correlation was not significant. However, the total protein content of pod showed a strong and positive correlation with pod damage. Total phenol content of flower bud showed strong negative correlation with damage parameters. Polyphenol oxidase activity in flower bud and pod exhibited a strong negative correlation with damage parameters. The crude fibre content of pod also showed a strong negative correlation with pod damage. In experiment 3, three SSR primers viz., CLM0061, CLM0295 and CLM0300 recorded high polymorphic information content (0.70, 0.71 and 0.76, respectively). Primer CLM0190 observed to have high amplicon size (307.03-415.73 bp). Jaccard’s similarity coefficient was highest between IC 52118 and IC 39916 (0.643) and was lowest between Kashi Kanchan and TVX-944 (0.022). Cluster analysis of SSR data grouped 30 genotypes in 22 clusters, and the 21 st cluster was observed to have more members (3 genotypes). Most resistant genotype, IC 2918, grouped in a separate cluster which proved its diverse nature from other genotypes. Principal component analysis of SSR data placed three yard-long bean genotypes viz., Geethika, Vellayani Jyothika and Lola near to each other in a two-dimensional score plot. The same analysis also formed two clusters with more number of genotypes which placed resistant and susceptible genotypes separately. In field screening of F 1 hybrids, Hybrid 20 observed to have total damage below 5 per cent. Eight hybrids recorded total damage in the range of 5 to 10 per cent. These hybrids were selected for next experiment. Line × Tester analysis of F 1 s revealed Kashi Kanchan, EC 98668 and IC 2918 as a good combiner for resistance against spotted pod borer. Hybrid 5, Hybrid 6, Hybrid 10, Hybrid 11, Hybrid 13, Hybrid 15, Hybrid 16, Hybrid 17, Hybrid 18, Hybrid 19 and Hybrid 20 observed to have desired negative heterosis (mid-parent) for total damage. In F 2 plant screening, Hybrid 1 population recorded low mean for total damage (6.76 %), whereas, the population of Hybrid 3 recorded high mean (12.17 %). Around 100 plants of F 2 generation recorded total damage below ten per cent. Out of them, around 38 plants also registered good yield. These plants should be further evaluated to isolate high yielding resistant segregants.
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    ThesisItemOpen Access
    Genetic evaluation of F2 generation for yield and water stress tolerence in upland rice
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2018) Ivy Mary, Rajan; KAU; Lekha Rani, C
    The present study entitled “Genetic evaluation of F2 generation for yield and water stress tolerance in upland rice” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2016-2018. The objective was to evaluate the pattern of variability in F2 for yield and yield contributing traits under upland and drought situations and to select superior segregants combining drought tolerance and high yield. The study material included four parents and three F2 populations selected from the Ph.D project entitled “Genetic analysis of drought tolerance in rice (Oryza sativa L.)”. The study comprised of two experiments .In experiment- I, the parents and F2 segregants were raised under rainfed upland condition exposed to natural stress. Among the F2 populations, Vaishak x Harsha (T6) recorded the highest mean grain yield plantˉ1 (38.45g – 48.15g) and lowest mean spikelet sterility (7.76%-21.18%). T6 recorded the highest mean values for number of productive tillers plantˉ1 (9 - 16) and leaf area index (mean: 1.67). Vaishak x Vyttila 6 (T5) recorded the highest mean values for number of spikelets panicleˉ1 (149 - 178), harvest index (44.88% – 48.15%) and proline content (mean: 0.29mg g−1). Thottacheera x Harsha (T7) recorded the highest mean values for chlorophyll(mean: 1.78mg g−1) and leaf soluble protein content (mean: 9.36mg g−1). The data obtained was subjected to transgressive segregation analysis and in T5 more than 50 percent positive segregants were observed for number of productive tillers plantˉ1, spikelet sterility, number of spikelets panicleˉ1 and panicle length. T6 recorded high percentage of positive segregants for number of productive tillersˉ1, grain yield plantˉ1, plant height and spikelet sterility. In T7 percentage of positive segregants were the highest for spikelet sterility and number of productive tillers plantˉ1. Dendrogram drawn on the basis of squared Euclidean distances classified the genotypes into four clusters. Cluster I -T1,T5,T6, cluster II- T4, cluster III -T2,T7 and cluster IV-T3. In experiment II, another set of parents and F2 segregants were grown under rainshelter imposing reproductive stage moisture stress. Irrigation was given at 20mm depth once in seven days from panicle initiation stage onwards. Among the F2 segregants, T5 recorded the highest mean values for grain yield plantˉ1 (11.80g – 18.88g), number of spikelets panicleˉ1 (128 - 174), grain weight panicleˉ1 (2.60g – 4.33g ), harvest index (42.44 % - 68.13%) and proline content (mean: 0.57) and the lowest for spikelet sterility (5.50% - 22.27%). T6 recorded the highest mean value for panicle length (19.60cm – 27.50cm). T7 marked the highest mean values for number of productive tillers plantˉ1 (3 – 7), chlorophyll (mean: 1.28mg g−1) and leaf soluble protein content(mean: 8.82mg g−1) and leaf area index (mean: 0.71). In T5, more than 50 percent of positive segregants were recorded for grain weight panicleˉ1, number of filled grains panicleˉ1 and number of spikelets panicleˉ1. T6 recorded higher percentage of positive segregants for straw yield plantˉ1 whereas T7 recorded the highest positive segregants for 1000 grain weight. On the basis of dendrogram drawn the genotypes were grouped into four clusters. Cluster I -T4 and T6, cluster II-T2,T7, cluster III - T3, T5 and cluster IV - T1. Among the F2 segregants, Vaishak x Harsha (T6) performed well under upland condition whereas Vaishak x Vyttila 6 (T5) performed well under stress. The high yielding variety Vaishak released for uplands might have transferred its superior yield characters to the progeny. The transgressive segregants with favourable traits thus obtained can be effectively utilised for selecting superior genotypes combining drought tolerance and high yield.
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    ThesisItemOpen Access
    Genetic evaluation of F2 generation for yield and water stress tolerence in upland rice
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2018) Ivy Mary, Rajan; KAU; Lekha Rani, C
    The present study entitled “Genetic evaluation of F2 generation for yield and water stress tolerance in upland rice” was carried out in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani during 2016-2018. The objective was to evaluate the pattern of variability in F2 for yield and yield contributing traits under upland and drought situations and to select superior segregants combining drought tolerance and high yield. The study material included four parents and three F2 populations selected from the Ph.D project entitled “Genetic analysis of drought tolerance in rice (Oryza sativa L.)”. The study comprised of two experiments .In experiment- I, the parents and F2 segregants were raised under rainfed upland condition exposed to natural stress. Among the F2 populations, Vaishak x Harsha (T6) recorded the highest mean grain yield plantˉ1 (38.45g – 48.15g) and lowest mean spikelet sterility (7.76%-21.18%). T6 recorded the highest mean values for number of productive tillers plantˉ1 (9 - 16) and leaf area index (mean: 1.67). Vaishak x Vyttila 6 (T5) recorded the highest mean values for number of spikelets panicleˉ1 (149 - 178), harvest index (44.88% – 48.15%) and proline content (mean: 0.29mg g−1). Thottacheera x Harsha (T7) recorded the highest mean values for chlorophyll(mean: 1.78mg g−1) and leaf soluble protein content (mean: 9.36mg g−1). The data obtained was subjected to transgressive segregation analysis and in T5 more than 50 percent positive segregants were observed for number of productive tillers plantˉ1, spikelet sterility, number of spikelets panicleˉ1 and panicle length. T6 recorded high percentage of positive segregants for number of productive tillersˉ1, grain yield plantˉ1, plant height and spikelet sterility. In T7 percentage of positive segregants were the highest for spikelet sterility and number of productive tillers plantˉ1. Dendrogram drawn on the basis of squared Euclidean distances classified the genotypes into four clusters. Cluster I -T1,T5,T6, cluster II- T4, cluster III -T2,T7 and cluster IV-T3. In experiment II, another set of parents and F2 segregants were grown under rainshelter imposing reproductive stage moisture stress. Irrigation was given at 20mm depth once in seven days from panicle initiation stage onwards. Among the F2 segregants, T5 recorded the highest mean values for grain yield plantˉ1 (11.80g – 18.88g), number of spikelets panicleˉ1 (128 - 174), grain weight panicleˉ1 (2.60g – 4.33g ), harvest index (42.44 % - 68.13%) and proline content (mean: 0.57) and the lowest for spikelet sterility (5.50% - 22.27%). T6 recorded the highest mean value for panicle length (19.60cm – 27.50cm). T7 marked the highest mean values for number of productive tillers plantˉ1 (3 – 7), chlorophyll (mean: 1.28mg g−1) and leaf soluble protein content(mean: 8.82mg g−1) and leaf area index (mean: 0.71). In T5, more than 50 percent of positive segregants were recorded for grain weight panicleˉ1, number of filled grains panicleˉ1 and number of spikelets panicleˉ1. T6 recorded higher percentage of positive segregants for straw yield plantˉ1 whereas T7 recorded the highest positive segregants for 1000 grain weight. On the basis of dendrogram drawn the genotypes were grouped into four clusters. Cluster I -T4 and T6, cluster II-T2,T7, cluster III - T3, T5 and cluster IV - T1. Among the F2 segregants, Vaishak x Harsha (T6) performed well under upland condition whereas Vaishak x Vyttila 6 (T5) performed well under stress. The high yielding variety Vaishak released for uplands might have transferred its superior yield characters to the progeny. The transgressive segregants with favourable traits thus obtained can be effectively utilised for selecting superior genotypes combining drought tolerance and high yield.
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    ThesisItemOpen Access
    Diversity analysis in landraces of rice(oryza sativa L.) in Wayanad through morphological and molecular polymorphism study
    (Department of Plant Breeding and Genetics,College of Horticulture, Vellanikkara, Thrissur, 2018) Manjunatha, G A; KAU; Elsy, C R
    The present investigation entitled “Diversity analysis in landraces of rice (Oryza sativa L.) in Wayanad through morphological and molecular polymorphism study” was conducted at the Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, Thrissur and Regional Agricultural Research Station, Ambalavayal, Wayanad during the period 2015- 2018. The study aimed to collect and characterize the rice landraces of Wayanad at morphological level and also to characterize the popular aromatic genotypes of the area at molecular level. DUS characterization revealed that, all the landraces under the study exhibited presence of leaf collar, absence of anthocyanin colouration of leaf collar, presence of leaf ligule, split shape of leaf ligule, absence of anthocyanin colouration for plant parts like lemma (keel), area below apex of lemma, stem nodes and presence of secondary branching in panicle. Variability was exhibited for majority of characters namely coleoptile colour, basal leaf sheath colour, intensity of green colour of leaf, anthocyanin colouration of plant parts like leaf, leaf sheath, auricles, ligules, lemma apex, area below apex of lemma, distribution of anthocyanin colouration in leaf, pubescence of leaf blade surface, leaf auricles, culm attitude, density of pubescence of lemma, colour of stigma, attitude of flag leaf blade, curvature of main axis of panicle, lemma and palea colour, presence and colour of awns, distribution of awns in panicle, secondary branching in panicle, attitude of branches in panicle, panicle exsertion, leaf senescence, sterile lemma colour, shape, colour and aroma of decorticated grain, gelatinization temperature and lodging nature.Thavalakannan, Mullan puncha and Sugandhamathi exhibited distinct morphological characters. Among the 60 landraces, Kanni kayama, Ambalavayal-1, Kothandan, Onamottan, Thondi-2, Chenthadi, Kannali and Thondi-1 exhibited significantly high grain yield per plant, which was on par with that of Uma and Aathira (high yielding check varieties), indicating the possibility of commercial cultivation of these cultivars. High PCV value than GCV for all the characters under study, indicated the influences of environmental factors on the characters. High heritability and high genetic gain was exhibited by the characters like length of leaf blade, width of leaf blade, stem thickness, stem length, number of tillers per plant, number of panicles per plant, length of panicle main axis, number of spikelets per panicle, number of grains per panicle, seed setting (per cent), 1000 grain weight, grain length, grain L/B ratio, decorticated grain L/B ratio and grain yield per plant, indicating that these characters could be used in crop improvement programmes. Character association studies including correlation and path-analysis revealed that, five characters viz., width of leaf blade, stem length, number of panicles per plant, weight of 1000 grains and decorticated grain width showed both positive correlation and positive direct effect on grain yield per plant. Cluster analysis based on qualitative characters categorized 60 landraces into 11 clusters at 74 percent similarity level. Based on D2 statistics analysis, the landraces were grouped into seven clusters with variable number of landraces in each cluster, indicating wide genetic diversity in the Wayanad landraces. All the inter-cluster distances were higher than the intra-cluster distance, indicating the wider genetic diversity among landraces of different clusters. Molecular characterization of aromatic rice genotypes of Wayanad by SSR (RM) profiling revealed high level of genetic polymorphism among the genotypes studied. Out of 86 SSR markers used for molecular characterization, 44 markers were polymorphic and remaining 42 were monomorphic. Maximum number of amplicons was exhibited by RM247 with five amplicons, followed by RM85, RM251, RM248 and RM493 with four amplicons each. The highest PIC value was exhibited by RM247 (0.90), followed by RM85, RM251 and RM493 with 0.88 PIC value each. Out of 86 SSR (RM) markers, 21 markers distinguished Basmati from traditional aromatic landraces of Wayanad viz., Gandhakasala and Jeerakasala. Seven SSR markers distinguished Gandhakasala from Jeerakasala, whereas 23 markers distinguished Basmati from Jeerakasala. Twenty-two markers distinguished Basmati from Gandhakasala and 23 markers distinguished aromatic group from non-aromatic group. Cluster analysis for molecular characterization revealed maximum similarity coefficient (1.00) within all the Jeerakasala morphotypes and all the Gandhakasala morphotypes. Cluster analysis effectively differentiated Basmati, Jeerakasala, Gandhakasala, Uma and Aathira from each other. Among the five clusters formed, cluster III was the largest one comprising all the 12 Gandhakasala morphotypes, followed by cluster IV with all Jeerakasala morphotypes. Cluster I, Cluster II and Cluster V exhibited one genotype each namely Aathira, Uma and Basmati, indicating their genetic distinctness.
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    ThesisItemOpen Access
    Distant hybridization and compatibility studies in wild orchids
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2018) Seeja, G; KAU; Arya, K
    The present investigation entitled “Distant hybridization and compatibility studies in wild orchids” was carried out with the objective of studying the cross compatibility through distant hybridization in wild orchids and molecular characterization of hybrid seedlings using RAPD/ISSR- markers. The study was carried out at Saraswathy Thangavelu Extension Centre of KSCSTE- JNTBGRI, Puthenthope, Thiruvananthapuram and at College of Agriculture, Vellayan, Thiruvananthapuram. The research work included experiment I, II, III and IV. Experiment I was carried out in two parts as evaluation of parents and hybridization, experiment II was cross compatibility studies of selected species, experiment III was in vitro culture of resultant hybrids and evaluation of seedlings and experiment IV was molecular characterization of hybrids. In experiment I, wild types belonging to different genera/species namely Vanda (Vanda tessellata, Vanda spathulata, Vanda sp.), Rhynchostylis retusa, Spathoglottis (Spathiglottis albida, Spathoglottis unguiculata, Spathoglottis gracilis, Spathoglottis plicata), Aerides ringens and Arundina graminifolia available at the orchid conservatory of Saraswathy Thangavelu Extension Centre of JNTBGRI, Puthenthope, Thiruvananthapuram were selected as parents based on variability in floral characteristics and these were evaluated for various quantitative and qualitative characters. Statistical analysis was carried out in Completely Randomized Design and analysis of variance revealed highly significant differences for all the biometrical characters included in the evaluation. Estimation of components of variance revealed that Phenotypic Coefficient of Variation (PCV) was higher than both Genotypic Coefficient of Variation (GCV) and Environmental Coefficient of Variation (ECV) for all the traits studied. PCV (143.93) and GCV (128.52) were the highest for number of spikes plant-1. Heritability was the highest for flower width (99.06 %) and it was high for all thirteen traits. Genetic advance as percent of mean was high for all the traits studied. It was the highest for number of spikes plant-1 (239.80). Estimated phenotypic correlation coefficient revealed highly significant and positive association between flower length and flower width (0.9519). The highly significant and negative association was obtained between internodal length and days for inflorescence emergence to first flower opening (-0.6896). Similarly genotypic correlation coefficient exhibited highly significant and positive association between flower length and flower width (0.9545) and highly significant and negative association between plant spread and number of leaves plant-1 (-0.9903). Based on this, parents were selected and were crossed in all possible combinations. In Vanda a hybrid evolved from the wild species was available at the centre and it was also crossed with the wild parents to study the cross compatibility of wild species with hybrids. In experiment II, cross compatibility of 152 cross combinations made was studied based on successful capsule setting. Capsule characteristics were recorded. The genus Spathoglottis took only four days for attaining pod setting whereas for the genus Rhynchostylis it was ten days for pod setting. Capsule attained maturity much earlier (30 days) in the genus Spathoglottis but the species Vanda spathulata took more days for attaining capsule maturity i.e., harvesting stage (150-154 days). In experiment III, capsules developed among thirty one cross combinations were subjected to seed culture for rapid germination under in vitro condition and seedling development. Observations regarding seed germination were recorded and seeds of ten crosses exhibited seed greening and initiation of protocorm development. Seeds of seven cross namely one intergeneric hybrid and six interspecific hybrids were developed into seedlings. Evaluation of hybrid seedlings was made based on variability in morphological characters at monthly intervals. The six interspecific hybrids were Spathoglottis unguiculata x Spathoglottis albida (Culture 622), Spathoglottis gracilis Spathoglottis unguiculata (Culture 652), Spathoglottis albida x Spathoglottis unguiculata (Culture 778), Spathoglottis albida x Spathoglottis unguiculata (Culture 1368), Spathoglottis plicata x Spathoglottis unguiculata (Culture 1386), Spathoglottis unguiculata x Spathoglottis plicata (Culture 1388) and intergeneric hybrid was Spathoglottis unguiculata x Vanda sp. (Culture 679). In experiment IV, molecular characterisation of seedlings evolved through the crossing was done based on ISSR analysis to distinguish F1 hybrid seedlings from selfed seedlings and their parents. Percentage of polymorphism between hybrids and parents ranged from 11.99 to 32.97 and these results confirmed that all the seven crossed seedlings tested were F1 hybrids and these were distinct from their relevant parents. The above study revealed that through distant hybridization in wild orchids, one intergeneric hybrid Spathoglottis unguiculata x Vanda sp. and six interspecific hybrids viz., Spathoglottis unguiculata x Spathoglottis albida, Spathoglottis gracilis x Spathoglottis unguiculata, Spathoglottis albida x Spathoglottis unguiculata, Spathoglottis albida x Spathoglottis unguiculata, Spathoglottis plicata x Spathoglottis unguiculata, Spathoglottis unguiculata x Spathoglottis plicata could be obtained and molecular characterization confirmed the hybridity of the intergeneric and interspecific hybrids. Therefore, the intergeneric and six interspecific F1 hybrids evolved through distant hybridization can be carried forward for the development of varieties or can be utilised for genetic improvement programme in future.
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    ThesisItemOpen Access
    Characterization and hybridization of nymphaea spp.
    (Department of Plant Breeding and Genetics, College of Agriiculture, Padannakkad, 2018) Manju, A; KAU; Namboodiri Raji, Vasudevan
    The investigation on "Characterization and hybridization in Nymphaea spp. " was undertaken in College of Agriculture, Padannakkad in the academic year 2016-18 with the objective to study the morphology, reproductive biology and to hybridize the seed forming Nymphaea sp. Based on the detailed survey in Northern Kerala, fourteen accessions were collected, of which ten were selected for detailed study. These consisted of two night blooming (Acc. 5 and Acc. 6) and eight day blooming types. Based on flower colour variation, there were accessions with different shades of pink (Acc.1, Acc. 2, Acc. 6, Acc. 9 and Acc. 10), blue violet (Acc. 3 and Acc. 8), white (Acc. 4 and Acc. 5) and violet (Acc.7). Growth and development pattern of leaves and flowers were similar in all the accessions. However, the ten accessions were distinct based on the leaf and floral characters. The leaves in all the accessions were simple orbicular with subpeltate lamina deeply cleft near to the petiole base. There was considerable variability in the colour, margin and tip of leaf lamina. The biometric characteristics of leaf such as length and width of lamina, length of petiole and longevity of leaf showed variability among the accessions, with Acc. 2 showing maximum length and longevity of the leaf. Flowers were pedicellate and complete with all the floral whorls in a spiral fashion on the floral axis. The process of opening and closing of flower repeated for four consecutive days, except in Acc. 6 where it continued till fifth day. Significant variation observed in flower morphology, anthesis and periodicity of flowering in all accessions with critical difference between day and night bloomers. The night blooming accessions showed superiority over day bloomers in the flower bud characters viz., length and circumference of flower bud and diameter of fully opened flower. The day bloomers differed from night bloomers in having shorter stigmatic appendages and stamens with terminal appendages. The night blooming accessions showed maximum duration for flower opening but low frequency of flowering compared to day bloomers. In general, all the accessions displayed strong protogyny except Acc. 5, where the phases of stigma receptivity and anther dehiscence were found overlapping. The pattern of anther dehiscence, duration of stigma receptivity and fragrance were favoring cross pollination in day blooming accessions. The adaptations such as overlapping of stigma receptivity and anther dehiscence in Acc. 5, simultaneous dehiscence of all anthers and absence of fragrance in both the night bloomers were pointing towards autogamy in these accessions. Pollen grains of all the ten accessions showed regular staining with 1% safranin. The in vitro pollen germination was maximum in 10% sucrose medium with seven accessions (viz., Acc. 1, Acc. 3, Acc. 4, Acc. 5, Acc. 6, Acc. 7 and Acc. 9) showing a remarkable increase in the pollen tube length. Only five accessions (Acc.3, Acc. 4, Acc. 5, Acc. 6, and Acc. 7) produced fruit and seeds in open condition with and without emasculation and no seed set under protected condition. The germinability and speed of seed germination was low without any treatments. Chemical scarification with different concentrations of H2SO4, GA3 and Ethrel showed an enhancement in seed germination, with maximum germination at a concentration of 100 ppm GA3 and 5% H2SO4. Besides rhizome propagation, other methods like leaf proliferation (Acc. 1 and Acc.7) and root tip proliferation (Acc. 5) were also observed. These alternative modes of propagation showed earliness in the formation of leaf, root and flowers compared to rhizome. Hybridization among five seed forming accessions showed success only among day bloomers (Ac. 3, Acc. 4 and Acc. 7) and with seed set in three crosses. Only the seedlings of cross 1 (Acc. 4 x Acc. 3) established successfully and produced flower within five months of seed germination. The initial evaluation of the morphological characters of hybrid progeny showed similarity with either of the parent for some characters. The colour of flower, color and shape of leaf were intermediate to both the parents and number of petals, stamens and carpels were unique to the hybrid progeny.