Loading...
Theses
Browse
62 results
Search Results
ThesisItem Open Access Divergence studies in pumpkin (Cucurbita moschata Pair)(Department of Olericulture, College of Horticulture, Vellanikkara, 1989) Suresh Babu, V; KAU; Gopalakrishnan, T RThe present investigation on "Divergence studies in pumpkin (Cucurbita moschat a Poir ) was conducted at the College of Horticulture , Vellanikkara, Trissur during June 1988 - Marc h 1989. Seventy one pumpkin genotypes collected from different part of India and abroad were utilized for the study. The extent of variability and divergence among 50 selected genotypes were assessed and grouped into 5 clusters based on Mahalanobis D2 statistic . Cluster I, II, III, I V and V contained 2, 7, 9, 12 and 20 genotypes respectively y . Intercluster distance was maximum between clusters I and II and was minimum between clusters III and V . Cluster I showed maximum average intercluster distance with any other cluster. Screening 71 genotypes for resistance/ tolerance to pumpkin mosaic and yellow vein mosaic diseases revealed that all genotypes except C M 214 were susceptible. Artificial inoculation studies confirmed immunity of C M 214 (Nigerian Iocal ) to pumpkin mosaic virus and yellow vein mosaic virus .ThesisItem Open Access Homeostatic analysis of components of genetic variance and inheritance of fruit colour, fruit shape and bitterness in bitter gourd (Momordica charantia L.)(Department of Olericulture, College of Horticulture, Vellanikkara, 1989) Abdul Vahab, M; KAU; Gopalakrishnan, P KThesisItem Open Access In vitro studies on the propagation of cardamom (Elettaria cardamomum maton)(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1989) Reghunath, B R; KAU; Gopalakrishnan, P KThesisItem Open Access Effect of growth regulators on flowering pollination and seed-set in ginger(zingiber officinale, rose)(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1984) Usha, K; KAU; Balakrishnan, SFlowering behaviour and floral biology of Rio-de-Janeiro and Maran and the effect of growth regulators viz., kinetin (5, 10 and 15 ppm), Ethrel (25, 50 and 100 ppm) and NAA (10, 25 and 50 ppm) in combination with two per cent urea and without urea on flowering, pollination and seed-set in Rio-de-Janeiro were studied at the College of Horticulture, Kerala Agricultural university, Vellanikkara during 1981-’83. The objective of the investigation was to assess the available varieties of ginger for flowering behaviour and to evaluate the effect of growth regulators with and without urea on the flowering behaviour, floral biology, floral structure, pollination and seed- set in Rio-de-Janeiro. (The possibility of overcoming the problems of shy and irregular flowering, poor pollen germination and the failure to set seeds also was explored during the investigation). (Among the 25 varieties studied, flowering was observed only in two varieties viz., Rio-de-Janeiro and Maran). Considerable variation was noticed between Rio-de-Janeiro and Maran with respect to flowering behaviour, extent of flowering, types of inflorescence, time taken for scape development, anthesis, anther dehiscence, pollen production, pollen fertility, style length and ovary length. Long but thin style was noticed both in Rio-de-Janero and Maran. Irrespective of the variety, flowers were found to rot/ and dry within 16 hours after flower opening. The maximum pollen germination (6.20 per cent) was obtained in the medium containing eight per cent sucrose, three per cent gelatin and 60 ppm boric acid under moist cotton covering in BOD incubator (26.50C). Coiling of the pollen tube during the advanced stages of growth was noticed. Pollination carried out in Rio-de-Janeiro and Maran employing the variables like stage of flower (bud stage, immediately after flower opening and three hours after flower opening), condition of stigma (partial and complete removal of style), density of pollen (smearing once, twice and thrice with standard brush), mixed pollen (ginger pollen with either Alpinia, Hedychium, Kaempheria or Costus pollen) and supplementary pollination (repeated pollination twice at two hours interval) failed to record any positive evidence of seed-set. Effect of growth regulators and urea on flowering behaviour, inflorescence characteristics and floral structures of ginger was evidenced during the study. ( Favourable influence of NAA 50 ppm on inducing early flowering, kinetin 15 ppm on the duration of flowering, NAA and kinetin on inflorescence production, NAA 50 ppm without urea on the number of flowers per inflorescence, NAA 10 ppm and all the three levels of kinetin on pollen production, NAA on pollen diameter, higher levels of Kinetin and Ethrel and lower levels of NAA on exine thinning, Ethrel 25 ppm in combination with urea, Kinetin 15 ppm with urea, NAA 50 ppm and Kinetin 10 ppm on pollen fertility, lower levels of Kinetin and Ethrel on reducing the style length, Kinetin 15 ppm and NAA 10 ppm on ovary length, Ethrel 25 ppm with urea and higher levels of NAA and Kinetin on pollen germination and NAA 50 ppm on pollen tube growth was revealed during the study.) Floral biology of Rio-de-Janeiro was not influenced by growth regulator and urea treatments. Abnormal floral structures occurred as isolated cases and therefore the role of growth regulators and urea in this respect was not clear from the results. (Pollination carried out in ginger (var.Rio-de-Janeiro) plants, subjected to growth regulator treatments with and without urea, employing the variables like stage of flower, condition of stigma, density of pollen, mixed pollen and supplementary pollination failed to result in seed-set.)ThesisItem Open Access Physiological investigations in relation to flowering, fruit set and capsule developmentj of cardamom (elettaria cardamomum maton)(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1986) Vasantha Kumar, K; KAU; Mohanakumaran, NInvestigations were carried out at the Cardamom Research Station, Pampadumpara and at the College of Horticulture, Vellanikkara during 1982 – ’84 to gather information on the physiological factors governing flowering, fruit set and capsule development of the three popular cardamom cultivars, Malabar, Mysore and Vazhukka. Emphasis had been given to unravel the causes of fruit (Capsule) shedding so as to evolve methods of control. Studies on growth and development in a broad sense depicted that an individual tiller of cardamom had a biennial growth habit. The different aspects of flowering and fruit set studied. Indicated that the variability was high in the Vazhukka cultivar and low in the Mysore cultivar. An early crop bearing habit was exhibited by Malabar, whereas Mysore possessed a late bearing habit and Vazhukka exhibited varying trends. The percentage of fruit set was high in Vazhukka, followed by Malabar and Mysore. Influence of climatic components on the physiology of flowering showed that a distinct dry spell triggered the panicle initiation process. The onset of rain coupled with high temperature was congenial for flower opening. A high soil moisture status combined with a high status of relative humidity (which resulted from a well distributed rainfall) enhanced the setting of capsules. Histological studies conducted in the genotype PV-1 (Malabar) showed that differentiation of panicle primordial was more during November to March. A prominent vascular zonation was observed in the rhizome nodes prior to the initiation of panicle promordia. Histology of the seeds revealed the development of starch grains at the greenish- yellow seed stage. Biological assays for endogenous auxins, inhibitors and cytokinins in the developing capsules indicated a spurt in auxin and cytokinin activity preparatory to fruit set. The level of inhibitory substances rose after the fruit set stage, while that of auxins fell which favoured the formation of an abscission zone causing shedding of immature capsules. Exogenous application of NAA (40 ppm) and 2, 4-D (4 ppm) increased the plant height, enhanced the production of panicles and flowers, reduced dropping of immature capsules and increased the yield. The uptake of nutrients revealed that cardamom is a heavy feeder of potash. The Vazhukka and Malabar cultivars developed less nutrients than the Mysore cultivar for producing unit yield of capsules. Radiotracer studies showed that the photosynthetic efficiency of cardamom was more under low light intensities. The rhizome was found to be the main sink in a cardamom tiller. Gas chromatographic estimation of cardamom oils indicated that the Mysore genotype (PR-107) was superior in quality aspects (because of high content of the esters, alpha terpenyl acetate, geranyl acetate and linalyl acetate) when compared with the Vazhukka genotype (PV-5) and Malabar genotype (PV-1). For consumption as a spice as well as for distillation of the essential oils, the black seed stages (‘karimkai’) was the most idel stage in cardamom.ThesisItem Open Access Screening for resistance to aphis craccivora in vegetable cowpea and evaluation of early types(Department of Olericulture, College of Horticulture, Vellanikkara, 1984) Sulochana, K A; KAU; Peter, K VCowpea Vigna unguiculata (L) walp is an important legume grown both in tropics and sub tropics. Eighty three cowpea lines were evaluated for field resistance to Aphis craccivora. All the lines except 10 TVU lines were infested by the aphid before 30 days after sowing. The lines TVU 1889, TVU 408, TVU 2896 and TVU 2962 were completely free from aphid infestation observed on leaves internodes and pods upto 60 days of sowing during the first crop season. The resistance reaction observed during second crop season and under controlled aphid infestation revealed that TVU 1889 was the most promising as far as aphid resistance is concerned. There are considerable variability in the cowpea for different characters and the lines K 1552 and TVU 1892 were the earliest to harvest (52 days). Among the weather parameters average number of rainy days and relative humidity had negative relationship with aphid population. Fifteen selected varieties of vegetable cowpea were grown in two seasons under two fertility levels. There were considerable variability in the vegetable types of cowpea for earliness which is important for the crop to be fitted in a multiple cropping system. The variety K 1552 was the earliest (52.13 days) followed by K 868 (52.43 days). The line IIHR 6-1-B is the most average stable variety with the highest mean (62.35 g) and bi value tending to one (0.96). The varieties K 1552, VS 89 and K 868 were high yielders but had bi value more than one and are suited for high yielding environments. The chemical analysis of pods for monosaccharides to polysaccharides ratio indicated that the yard long bean had the highest ratio followed by K 1552, IIHR 6-1-B and VS 87.ThesisItem Open Access Effect of gamma irradiation in ginger(Department of Horticulture (Plantation Crops and Spices), College of Horticulture, Vellanikkara, 1984) Giridharan, M P; KAU; Balakrishnan, SInvestigation was carried out at the College of Horticulture, Vellanikkara, during 1983 – 84, to study the effect of gamma irradiation on germination, vegetative growth, flowering, yield, quality attributes and incidence of soft rot disease in ginger using four doses of gamma rays (0.7, 1, 1.5, 2.k rad). Irradiation treatments produced inhibitory effects on the germination of ginger rhizomes. The plant height, tiller production, leaf production, leaf size and leaf area index decreased with the increase in irradiation dosages. Flowering behaviour of ginger could not be altered by the levels of gamma irradiation tried. Rhizome yield reduced as the irradiation dose increased. The treatments did not differ significantly with regard to essential oil and oleoresin content of both green and dry ginger ; oleoresin of ginger peel and percentage recovery of dry rhizomes. However, the incidence of soft rot disease could be highly reduced by gamma irradiation.ThesisItem Open Access Evaluation of a set of non-segragating and segragating populations of tomato for field resistance to bacterial wilt(Department of Olericulture, College of Horticulture, Vellanikkara, 1985) NarayananKutty, C; KAU; Peter, K VBacterial wilt caused by Pseudomonas solanacearum E.F. Smith is the single limiting factor for tomato cultivation in the warm humid tropical soils of Kerala. The susceptibility of reportedly resistant varieties elsewhere necessitates the need for continuous evaluation of tomato lines for wilt resistance. An experiment was planned and carried out during 1983-’85 at the College of Horticulture, Vellanikkara to identify new sources of resistance to bacterial wilt. The susceptible check Pusa Ruby showed 100% susceptibility in all the trials. The F2 hybrids of Saturn and LE 79 were found resistant, out of the four non-segregating (Saturn, LE 79, Pusa Ruby and Pusa Ruby x LE 79 F1) and two segregating populations (Pusa Ruby x LE 79 F2, Saturn x LE 79 F2) evaluated. In a repeated trial F3s were also evaluated along with the F2s and non-segregating populations (Saturn and FE 79). Resistance was observed in Saturn x LE 79 F3 (percentage wilt, 10.7) and Saturn x LE 79 F2 (percentage wilt, 18.23). Pusa Ruby x LE 79 F2 s and F3s were susceptible to moderately susceptible. Among the non-segregating populations, LE 79 showed moderate resistance, while Saturn was moderately susceptible to susceptible in both the trials. Information on days to fruit set, days to harvest, fruit yield/plant and average fruit weight were also gathered. A higher average fruit weight (44.63g) was observed in the resistant Saturn x LE 79 F3s. Evaluation of 15 reportedly resistant lines of tomato confirmed resistance in LE 79 LFG and LE 217. The line LE 79 LFG was also medium fruited (40.1g) and high yielding. Concentric cracking and irregular cracking were observed higher than radial cracking in all the lines evaluated. Fruit set ranging from 50 to 63% was observed in all the lines at higher night temperatures (230C average). Genetics of fruit shoulder colour revealed that white colour was recessive to green and governed by a single gene. Evaluation techniques like root dipping in bacterial culture and planting, stem inoculation in leaf axil and alternate row planting were compared with spot-planting for efficiency. Spot-planting was found easier and effective. The chances for escape are negligible in this method of evaluation.ThesisItem Open Access Radiation induced variability in interspecific hybrids involving abolmoschus esculentus moench and abolmoschus manihot(Department of Olericulture, College of Horticulture, Vellanikkara, 1986) Dalia Cherian; KAU; Peter, K VYellow vein mosaic is the most destructive viral disease of bhindi, which takes heavy toll of the crop, infecting at all growth stages. Attempts to isolate source(s) of resistance to yellow vein mosaic disease from cultivars and wild relatives were proved to be of limited success because of either incompatibility or sterility barriers between the cultivars and wild relatives. An experiment was planned and carried out during June - October,1984; November - April, 1984-'85 and June - October 1985 at the Instructional Farm _ of the College of Horticulture, Vellanikkara, Trichur to induce variability in interspecific hybrids involving Abolmoschus esculetus (L.) Moench and Abolmoschus manihot (L.) Medic. The three accessions of Abolmoschus manihot were observed cross compatible with Abolmoschus esculentus cv. ‘Pusa Sawani', Abolmoschus menihot sap, tetraphyllus crossed readily with abolmoschus esculentus (Cl = 95%) . This was proved through Fo fruit set, Fo seed set and germination of F0 seeds. The F1 plants did not bear normal seeds and F2 generation could not be raised. The pollen fertility of F1 hybrids were much lower than the parents. There was reciprocal difference in the crossability index. radiation created considerable variability in interspecific F1 hybrids for days to flower, plant height,leaf length, leaf width, fruit length, fruit girth, nodes on main stem, fruiting nodes on main stem, intemodal length, fruits/plant, ridges/fruit and fruit yield/plant, in Abolmoschus esculentus x 2 accessions of Abolmoschus manihot. There was preponderance of characters of Abolmoschus manihot in the interspecific hybrids. Considerable changes in discrete characters were observed in irradiated F1 hybrids. Dominant characters like branched habit, pubescence and pigmentation of vegetative parts, and hairiness of fruit got changed with gamma radiation. Though the radiation enhanced the pollen fertility of interspecific hybrids, they had seedless fruits or fruits with incompletely filled seeds. With the doses 15 kR, 20 kR and 25 kR tried, quantitative and qualitative characters were affected, though there appeared to be scope for the use of still higher dose of rays to create wider variability in interspecific hybrids. Under natural field conditions and artificial inoculation, ‘Pusa Sawani’ was infected by yellow vein mosaic virus, whereas none of the wild species did exhibit any symptoms. Artificial inoculation provides a means to select desirable plant types having resistance to yellow vein mosaic disease.
