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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 Studies on growth and bearing habits of certain varieties of bhendi (Abelmoschus esculentus (L.) Moench.)with special reference to fruit maturity and quality(Regional post-graduate training centre, Agricultural college and research institute, Coimbatore., 1964) Ravindra, K; KAUThesisItem Open Access Investigations on intervarietal F2 hybrids in cowpea(Department of Agricultural Botany, College of Horticulture Vellanikkara, Trichur, 1981) Sumathikutty Amma, B; KAU; Narayanan Namboodiri, K MCcwpea (Vlgna ungiculata) Is the major pulse crop cultivated in Kerala where the average yield of pulses in general and Cowpea in particular is very low even under modern agronomic practices* This low productivity is mainly due to the absence of high yielding varieties suited for the different agro-climatic conditions. The varietal requirements in Cowpea, in the state vary because of the highly contrasting system of cultivation and this compels Cowpea breeders to evolve varieties of different combinations of plant, pod and seed characters, This is possible by producing different varieties combining the desirable attributes required for the diverse situations by suitable means. One of the ways by which, this can be achieved is through combination breeding in which desirable genes are pooled frcra different sources* In a previous study conducted in the Department of Agricultural Botany, the 202 genotypes v/ere grouped into 17 distinct clusters. Representing 15 clusters, 15 varieties were chosen for intervarietal hybridisation and their F^'s evaluated during 1979-80, Seeds collected from the plants of the 16 Intervariota] crosses along with their parents were used for the study. Two families In each of the 16 crosses were studied along with their respective parents for the pattern of inheritance of 15 economic characters. Most of the characters were found to be inherited as quantitative characters controlled by either polygenes or by a few major genes with their action being suitably modified by minor genes. The crosses 5 x 15 (g p .p l s . 139 x p .118) and 6 X 8 (Red Seeded Selection X Kolingipayar) were identified as suitable ones for grain - production and also for using as dual purpose Cowpea culture since they might throw segregants best suited to those purposes. For the specialised system of Cot/pea culture practised in summer rice fallows exclusively for vegetable purpose, the crosses 14 X 16 (Pannithodan-early X Kolingipayarwhite), 17 X 16 (Mancheri-black X Kolingipayar^hite) and 10 X 6 (IC. 20729 X Red Seeded Selection) appeared to be the Ideal ones*ThesisItem Open Access Morphological studies and quality evaluation of ginger (zingiber officinale rosco) types(Department of Horticulture (Plantation Crops), College of Horticulture, Vellanikkara, 1978) Nybe, E V; KAU; Sivaraman Nair, P CA detailed study of 25 ginger types was conducted during the period from April 1977 to June 1978 at the College of Horticulture, Vellanikkara with a view to find out the feasibility of fixing up specific morphological characters to identify different types, to screen out ginger types with high yield, high quality and resistant or tolerant to pests and diseases and to study the quality variations at different periods of maturity. The study revealed that morphological characters are not reliable to classify the ginger types, although some of them can be identified by rhizome characters. The morphological characters such as length of leaf, leaf area index and number, length and girth of primary and secondary fingers were found to be positively correlated with yield. All the types studied are susceptible to the incidence of soft-rot, leaf –spot and shoot-borer. The type Maran was relatively tolerant to soft-rot whereas Rio-de-Janeiro was found to be the most susceptible type. Yield was found to vary significantly among the types studied. Maximum yield was recorded in Nadia followed by Bajpai, Maran and Narasapattom. Maximum oleoresin percentage was in Rio-de-Janeiro and highest percentage of oil recovery in Karakal. But the maximum yield per hectare of oleoresin and oil was in the type Maran. Fibre content was minimum in China and maximum in Kuruppampady closely followed by Maran. The yield, dryage and percentage of oleoresin, oil and crude fibre varied significantly among the different maturity periods studied. The percentage of oleoresin, oil and fibre was maximum at 165 days after planting. But the maximum yield per hectare of oleoresin and oil were found at 270, 195, 225 and 225 days after planting in Rio-de-Janeiro, Maran, Kuruppampady and Wynad Local respectively. Cultivation of the types Nadia, Bajpai and Maran is recommended for higher total yield of dry ginger for the plains of Kerala. Considering the low incidence of soft – rot and higher yield of oleoresin and ginger oil the type Maran is preferredThesisItem 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 Effect of growth regulators and certain formulations on bunch development in banana var. palayankodan(Department of Pomology & Floriculture and Landscaping, College of Horticulture, Vellanikkara, 1983) Rajendran, P; KAU; Aravindakshan, MThe yield of banana in Kerala remains very low inspite of the adoption of proper manuring and other management practices. Investigations have indicated that the main barrier to the increased production in banana is the lack of sufficient leaf area at the active phase of growth of the plants. The present experiment was conducted with the banana cultivar ‘Palayankodan’ under sparsely irrigated conditions with a view to increase the plant growth and ultimate yield by the use of growth regulators and commercially available formulations. The growth regulators viz., 2-4-D and NAA and the commercially available formulation namely ‘Navras Banana Special’ were tried at four different concentrations as given below:- 2,4-D - 5,10,15 and 20 ppm NAA - 20, 30,40 and 50 ppm ‘Navras’ - 0.25, 0.50,0.75 and 1.00 per cent The various chemicals at different concentrations were applied as two foliar sprays at three and four months after planting. A third spray was also given on the bunches immediately after the female phase of flower opening. On an overall analysis, 2,4-D at 20 ppm and ‘Navras’ at 0.50 per cent were found to be more effective in promoting the vegetative growth of plants. With respect to flowering and duration of the crop, the growth regulators alone had significant effects when compared to the commercial preparation ‘Navras’. The effectiveness also depended on the concentrations of the growth regulators. Thus 2,4-D at 20 ppm induced early shooting of plants by about 12 days whereas NAA at 50 ppm caused substantial delay in shooting. The chemicals at their various concentrations were not effective in influencing the bunch maturity, thus indicating that the applied chemicals caused the earliness or delay observed, through their influencedon the vegetative growth only. Consequent to the application of 2,4-D at 20 ppm the crop duration was advanced by 22 days. Contrary to this, NAA at 50 ppm delayed the duration of the crop. The treatments with 2,4-D at 5 to 20 ppm, NAA at 40 and 50 ppm and ‘Navras’ at 1.00 per cent were found to advance the ripening of fruits. The best quality fruits in terms of TSS and total sugars were obtained by the application of 2,4-D at 20 ppm. Among the concentrations of ‘Navras Banana Special’, o.5 per cent gave the best results with respect to the growth and yield of plants. When the concentration was increased further, there was a decrease in the performance of the plants. The optimum doze of ‘Narvas Banana Special’ was worked out to 0.534 per cent. The correlations worked out from the data collected revealed that the vegetative and bunch characters such as girth of psuedostem, number of functional leaves, total leaf area, length of bunch, number of hands and fingers per bunch, number of fingers per hand and weight of hand, length, girth and weight of fingers amply contributed to the overall yield in the form of bunch weight. The yield increase observed in the present study due to the application of 2,4-D at 20 ppm was by 88 per cent and that for ‘Navras’ at 0.5 per cent was by 96 per cent. The benefit/cost ratio worked out for these treatments did not differ and hence application of 2,4-D (20 ppm) and ‘Navras Banana Special’ (0.5 per cent) were equally good for increasing the yield. The present investigations were conducted under sparsely irrigated conditions where, irrigation was given just for the maintence of the crop. Further investigations with rainfed and irrigated ‘Palayankodan’ bananas may be of particular interest.ThesisItem Open Access Quality Characters Of Clove And Nutmeg At Different Stages Of Maturity(Department of Horticulture, College of Agriculture,vellayani, 1990) Manoj, A M; KAU; Vasanthakumar, KThe present investigation was carried out at the College of Agriculture, Vellayani during 1988 – 89. The objectives of this study were to characterise the growth pattern of clove flower buds and nutmeg fruits and to develop suitable harvest indices for these crops based on quality characteristics at different stages of maturity. The moisture content in clove buds and rind of nutmeg fruits increased with increase in maturity. However, moisture percentage in nutmeg kernel and mace was found to decrease as maturity advanced. The non – volatile ether extract (NVEE), on dry weight basis, was found to decrease on maturity advanced in clove buds and in mace while in nutmeg kernel the NVEE showed an increasing trend. The volatile oil in clove, nutmeg and mace was more at the immature stages and it progressively decreased at the peak harvesting stages. Eugenol, the chief component in clove oil was the maximum at the flowering stage. Hence for extraction of clove oil which is intended for use in medicine, dentistry and other pharmaceutical uses, it is advisable to harvest clove buds at the anthesis stage. The aromatic ethers which are the chief components that determine the flavour and drug action in nutmeg oil was the maximum one month prior to the fruit splitting stage. In mace oil it was found to be high two months prior to fruit splitting stage. So if nutmeg and mace oils are intended for medicinal purpose, then it may be worthwhile to harvest nutmeg fruits at the 6th month for extracting kernel oil and at the 5th month for extracting mace oil. Considering the fact that the nutmeg fruit yield both nutmeg and mace oil, harvesting separately at different maturity stages for extraction of the different oils is practically difficult. The aromatic phenol and phenol ethers showed a very low value in mace oil one month prior to fruit splitting. So in practice the fruit may be harvested two months prior to fruit splitting for extraction of both nutmeg and mace oils. However the high moisture content at this stage makes drying a problem. So such a practice of early harvesting of nutmeg fruits may be resorted to in places where facilities are available for extraction of oil from the fresh kernel and mace immediately after harvesting.ThesisItem Open Access Variability studies in the seedling progenies of T*D coconut hybrids(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1981) Valsala, P A; KAU; Kannan, KA study was conducted at the Instructional Farm , Vellanikkara , during 1979-80 with the objective of assessing the extent of variability in the seedling progenies obtained from open pollinated seednuts of tall x Dwarf (F1) palms Seednuts were collected from 30 Tall x Dwarf F1 palms belonging to six family groups and the experiment was laid out in completely randomised design with family groups as treatment and progeny as replication The present investigation emphasised the utility of selection of high yielding West Coast Tall palms in controlled mating for the production of Tall x Dwarf hybrids and showed the stability of superiority of Tall x Dwarf hybrids even under poor environmental conditions. The percentage of vigorous , medium and poor seedlings produced by each (F1) progeny was found to be independent of the productivity of the palm under open pollinated condition . There fore , collection of seednut from high yielding TxD progenies for further propagation should be resorted with great caution . Progenies of the same parent have shown considerable difference in respect of the number of days taken for germination giving an indication of the variability existing in the TXD palme , in their capacity for production of early bearing and high yielding f2 progency. The petiolar colour of the grand parents and f1 progenies were green, while the F2 progenies showed segregation with green , bronze, orange and yellow colour. Four progenies each of grand parents Vlll/23 and l/58, and two progenies each of Vlll/158, I/76, Vlll/143 and 1/109 have been identified as prepotents on the basis of seedling performance . Seasonal variations were noticed on yield, size and weight of nuts. The total chlorophyll content in the leaves of the vigorous seedling which were potential high yielders were found to be high. Early germinated nuts produced seedling having more collar girth and as such greater vigour.ThesisItem Open Access Biochemical characterisation of coconut palms in relation to yield(Department of Horticulture (Plantation Crops and Spices), College of Horticulture, Vellanikkara, 1983) Narayanan Kutty, M C; KAU; Gopalakrishnan, P KAn investigation on the morphological and chemical components of yield in coconut palms was conducted at the College of Horticulture, Vellanikkara during 1981-83, in order to characterise the yield of palms based on these characters. Sixty palms of the cultivar West Cost Tall (W.C.T.) were selected from the existing Plantation at Agricultural Research Station, Mannuthy comprising twenty palms each under low, medium and high yield groups (< 40, 40-80 and 80 nuts/palm/year respectively). Observations on morphological characters such as number of leaves, length of leaf, length of petiole, number of leaflets, length of leaflets, periodicity of leaf emergence and girth at collar were recorded at bimonthly intervals. Analysis of leaf samples from the leaf position 14 were taken up to estimate the contents of nitrogen, phosphorus, potassium, calcium, magnesium, soluble sugars, starch, total phenols, free amino acids, total chlorophyll, catalase activity and peroxidase activity during March-April and September-October seasons. There was a significant positive correlation for number of leaves, length of leaves, number of leaflets, length of leaflets and girth at collar with the mean annual yield. The periodicity of leaf emergence had a negative correlation with yield. Among the mineral nutrients, nitrogen and potassium had significant positive correlation with yield. Phosphorus, Calcium and magnesium failed to show any linear relationship. The nutrient ratios viz., N/Ca, K/P, K/Ca, K/Mg and K/Ca + Mg also exhibited significant positive correlation with yield. The biochemical components such as soluble sugars and total chlorophyll content in the leaf lamina had significant positive correlation with yield. Total phenolic compounds present in the leaf lamina had a significant negative correlation with yield. Starch content in the leaf did not show such relations. The free amino acids present in traces in the leaf were identified. Leaf catalase and peroxidase activity exhibited no definite pattern of variation in relation to yield
