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1984 - 198911990 - 19961
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Subject: Horticulture × Author: Baby Lissy Markose ×
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    ThesisItemOpen Access
    Pollen production, fertility and compatibility studies in shoe flower (Hibiscus Rosa-Sinensis L)
    (Department of Pomology, Floriculture and Landscapping, College of Horticulture, Vellanikkara, 1984) Baby Lissy Markose; KAU; Aravandakshan, M
    Investigations were conducted on the pollen morphology, production, fertility and compatibility in 34 types or varieties of Hibiscus rosa-sinensis L. and two other species viz., H. mutabilis L. and H. schizopetalus Hook, in the Department of Pomology and Floriculture, College of Horticulture, Kerala Agricultural University, during the year 1981-‘83. Since the types maintained did not possess any distinct varietal names, detailed morphological descriptions were made for identification. Observations were also made on certain aspects of blossom biology like flower opening, anther dehiscence, folding of corolla and retention of corolla. There was distinct variation in the morphology of flowers in the 36 types/varieties or species studied. Flower opening took place during the morning hours and in most of the types/varieties/species anther dehiscence commenced soon after flower opening. The time taken for the folding of the corolla ranged from 12 to 36 hours after flower opening and for the retention of corolla ranged from 24 to 72 hours. Pollen grains of Hibiscus were pantoporate, spheroidal and spinose and were 125.91 to 198.58 microns ( µ) 0 / in diameter. Pollen production per anther varied from 87 to 500 and percentage of pollen fertility ranged from 4.6 to 97. 4. Standardization of media for pollen germination and tube growth indicated that a medium consisting of 20 per cent sucrose + one per cent agar + 100 ppm boric acid was the best. The pollen grains commenced germination within 30 minutes of dusting and gave satisfactory germination even after four hours of incubation in the best medium. Of the 35 types/varieties/species tested, only in 23 cases, pollen germinated ,In vitro. Acc.11 showed maximum germination of 85.8 per cent followed by H. Mutabilis and Acc.2 while tube length was maximum in Acc.2 (962.48 µ) followed by Acc.11 and H. mutabilis. Polysiphonous germination was observed in majority of cases. Pollen grains could not be stored for more than three days in any of the methods employed in the present study. Of the different methods tried, storage of flowers with anther column intact at 4°C over calcium chloride in a desicator was found to be the best followed by storage of flowers at 4°C without calcium chloride. Acc.26 and Acc.11 had the longest shelf life followed by Acc.2. It was found that only Acc.2 and g. mutabilis set fruits naturally. Out of the seven types/varieties of H. rosa sinensis and two other species viz., H. mutabilis H. schizopetalus selfed, only-in five types or varieties of H. rosa-sinensis and in the species mutabilis self compatibility was noticed. The fruits matured in 28 to 38 days and germinated in 10 to 18 days. The number of seeds per capsule ranged from 8.5 to 192.5 and seed germination ranged from 3.33 to 69.77 per cent. Survival percentage of germinated seedlings was more than 95 per cent. Out of the intraspecific cross combinations tried, compatibility was observed in all the crosses except in cases where Acc.11 was used as the female parent. The cross Acc.2 x 11 had the highest crossability index followed by Acc.2 x 18, 2 x 26, 18 x 11, 22 x 11, 26 x 2 and 26 x 11. Interspecific compatibility was practically absent.
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    ThesisItemOpen Access
    Genetic and biochemical bases of resistance to bacterial wilt in chilli
    (Department Of Olericulture, College Of Horticulture, Vellanikkara, 1996) Baby Lissy Markose; KAU; Abdul Vahab, M
    Investigation on “Genetic and biochemical bases of resistance to bacterial wilt in chilli’ was carried out in the Department of Olericulture, College of Horticulture, Vellanikkara during 1992-96 to study the inheritance and mechanisms of bacterial wilt resistance and to develop a near isogenic line of Pusa Jwala with resistance to bacterial wilt. Pseudomonas solanacearum, the bacterial wilt pathogen was isolated from infected chilli plants and its pathogenicity was established. The resistance to this disease showed a monogenic and incompletely dominant type of inheritance. Studies on biochemical basis of resistance revealed that total phenol, OD phenol and protein content and enzyme activities had a positive association with bacterial wilt resistance. Ujwala, the resistant variety showed high protein content and had higher activities of peroxidase and polyphenol oxidase enzyme in all plant parts. Higher total phenol was found only in roots and OD phenol in roots and stems of Ujwala. All these biochemical constituents recorded an increasing trend on inoculation in both resistant and subsceptible varieties. The wilt resistant variety had higher OD phenol and protein contents on inoculation whereas the susceptible variety was higher in total phenol content. Both peroxidase and polyphenol oxidase activity were higher in resistant than in susceptible variety. The higher amount of OD phenol and their oxidation products like quinones formed by increased peroxidase and polyphenol oxidase were ascribed for resistance in Ujwala. In the protein gel electrophoresis, the resistant and susceptible genotypes possessed similar bands with identical electrophoretic mobility. The isozyme patterns of peroxidase and esterase were studied. Roots for peroxidase and leaves for esterase showed clear bands. The resistant and susceptible varieties were different in banding pattern before inoculation. Inoculation did not evince any change in the banding pattern for peroxidase and esterase enzymes. The resistant variety had a well developed secondary xylem with thick and compact piliferous layers and cortical cells compared to the susceptible variety. In the radiotracer studies, radioactivity counts were more in susceptible than in resistant variety after inoculation in both 32p and 35S labeled plants. In the autoradiography, the 35S labeled bacteria were more in susceptible plants than in resistant ones. However there was no appreciable difference between resistant and susceptible plants when 32P tagged bacteria were inoculated. A near isogenic line of Pusa Jwala, moderately resistant to bacterial wilt, was developed by crossing Ujwala with Pusa Jwala and advancing the F1s to BC2F4 generation.