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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 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.ThesisItem Open Access Relative advantages of F1 hybrids and 50:50 physical mixture in tomato(Department of Olericulture, College of Horticulture, Vellanikkara, 1986) Sheela, A G; KAU; Peter, K VBacterial wilt caused by Pseudomonas solanacearum E.F. Smith is the most serious disease limiting the successful cultivation of tomato (Lycopersicon esculentum Mill.) in the acidic soils of Kerala. Development of F1 hybrids possessing different resistant gene systems would be a desirable step in tomato improvement. Development of specific physical mixtures could also minimise crop damage considering the ‘Obstruction’ given by the component lines. Experiments were carried out during 1984-’85, at the Instructional Farm of College of Horticulture, Vellanikkara, Trichur to identify new sources of resistance to bacterial wilt. The susceptible check Pusa Ruby showed 100% susceptibility in all the trials. Six specific tomato lines-LE 79 LFE, LE 214, LE 217, IIHR Bwr 93, IIHR Bwr 34A and LE 206-were crossed in all possible combinations. All F1 hybrids except IIHR Bwr 93 x IIHR Bwr 34A and IIHR Bwr 34A x LE 206 were resistant to bacterial wilt. LE 214 x LE 206 were resistant to bacterial wilt. LE 214 x LE 206 (921.75 g/plant), the best F1 hybrid, had 27.15 fruit/plant and was earlier to fruit set (57.8 days) and fruit harvest (85 days). Among the 15 physical mixtures, six were resistant-LE 214 + LE 217 (16.67%), LE 214 + IIHR Bwr 93 (18.33%), LE 214 + IIHR Bwr 34A (10%), LE 217 + IIHR Bwr 34A (13.33%). LE 214 + IIHR Bwr 93, the best resistant physical mixture, had 24 fruits/plant weighting 600.38 g/plant. Intervarietal heterosis was observed for plant height, primary branches/plant, days to fruits/plant and fruit yield/plant. Combining ability analysis indicated the role of both additive and non-additive geneaction in the expression of days to fruit set, days to fruit harvest, and plant height. Additive gene action was predominant for primary branches/plant. A preponderance of non-additive gene action over additive gene action was observed for fruit/plant and fruit yield/plant. To study the maternal parental effect, five lines of tomato- LE 79 LFF, LE 214, LE 217, IIHR Bwr 93 and LE 206- were crossed in all possible combinations including reciprocals. Maternal parental effect was pronounced for days to fruit set, days to fruit harvest and fruit set (%). Evaluation of 15 reportedly resistant lines of tomato confirmed resistance in LE 211, LE 214, LE 217, LE 79 LFG and LE 79 DG. The line LE 79 LFG was the highest yield (742.6 g/plant) with 19.67 fruits/plant.ThesisItem Open Access Effect of varying light intensities on the growth and development of indoor foliage and flowering plants(Department of Horticulture, College of Agriculture, Vellayani, 1986) Aasha, K; Aasha, K; KAU; KAU; Ramachandran Nair, S; Ramachandran Nair, SAn investigation was carried out in the Department of Horticulture, College of Agriculture, Vellayani, during the year 1985-86 to find out the effect of various light intensities on the growth and development of the important indoor foliage and flowering plants such as aglaonea, aralia, alocasia, chlorophytum, coleus, cordyline, dieffenbachia, dracaena, maranta, peperomia, pleomale, rheo, balsam, begonia and verbena. The treatments consisted of five intensities of light as follows, Full sunlight 75,50, 25 and 10 per cent light. The experiment was laid in a Completely Randomised Design.Shading was provided by using gunny cloth streched over g.1 poles. Plant height increased with decrease in light intensities in most of the plants except in aralia, coleus, maranta, pleomele and aglaonema. In aglaonema the height of the plants were influenced by the treatments only at the initial growth stages. In other staller plants were produced under high light intensities. In general diminishing light intensities enhanced leaf production , leaf area and chlorophyll content in all plants except in coleus where leaf area increased with increase in intensities of light. Destruction of chlorophylll in the leaves of plants kept in the open as evidenced by the yellowish colour was not observed for those plants in shade.ThesisItem Open Access Enhancing sucker production In banana and Its effect on the bunch weight of the mother plant(Department of Horticulture, College of Agriculture, Vellayani, 1986) Lekha Sreedhar, R; KAU; Mohanakumaran, NNatural sucker production in seven .of the important cultivars of the State was assessed at the College of Agriculture, Vellayani during 1983-85* Attempts were also made to standardise a treatment/treatment combination that would generate a large number of comrmerciably acceptable suckers in 'Robusta' without much deleterious effects on the mother plants. Among the seven cultivars, ’Nhalipoovan* produced significantly larger number of suckers per mat (12.40 against 3.72 to 5.94). The natural sucker production in 'Robusta' was found to be fairly low (4.59 per mat against 12.40 per mat in 'NhalipoovanThesisItem Open Access Standardisation of propagation techniques in bread fruit (Artocarpus altilis (Park.) Fosberg)(Department of Horticulture, College of Agriculture, Vellayani, 1986) Jyothi, M L; KAU; Ramachandran Nair, SInvestigations were carried out at the Department of Horticulture, College of Agriculture, Vellayani during 1984-85 to standardise the most suitable method of vegetative propagation of bread fruit. The experiment was conducted in completely randomised design with root and stem cuttings and layering in order to find out the optimum thickness and. length of root and shoots end also the influence of growth regulators in enhancing the success with each of these methods. From the investigations it was found that root sittings were the mast; reliable end successful propagules compared to stem cuttings and layers. Thick roots were found to give comparitively more success In percentage of sprouting and the number of sprout per cutting Earlier sprouting and Easier growth of the sprouts were recorded from thin roots. The root development from the root cuttings was more from medium thick and thin cuttings. Longer root cuttings were more suited for propagation since they performed better in all characters except in secondary root development. Growth regulators had a negative effect on sprouting of root cuttings. Higher success in sprouting earlier sprouting and subsequent growth was obtained from untreated cuttings and also from those treated with NAA at lower concentration. However root development from the cuttings was found to be enhanced by growth regulator treatment compared to control. Among the growth regulators tried, NAA 300 ppm gave better results in the development of both primary and secondary roots.ThesisItem Open Access Effect of nutrition on the establishment and bud take in budded roses(Department of Horticulture, College of Agriculture, Vellayani, 1986) Ushakumari, S; Ramachandran, Nair SThesisItem Open Access Mineral nutrition of nutmeg (Myristica Fragrans Hout.) in relation to deficiency symptoms and flowering(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1986) Joseph Philip; KAU; Sivaraman Nair, P CDetailed investigations were carried out at the College of Horticulture, Kerala Agricultural University, Vellanikkara from 1982 to 1985 with a view to study the nutrient deficiency symptoms by inducing deficiency and to study the influence of carbohydrates, nutrient elements and their ratios on flowering of nutmeg. Deficiency symptoms of macro-nutrients except Ca and S were first manifested on the older leaves while that of micro-nutrients on younger leaves. Symptoms of N deficiency were expressed as yellowing of leaves with orange tinge except the midrib and lateral veins followed by development of brownish necrotic blotches with bright orange yellow halos. Bronze green to purple discolouration of leaves with purplish brown necrotic blotches were the symptoms of P deficiency. Potassium deficiency symptoms were characterized by chocolate brown necrosis along the leaf tip and margins which later progressed to the distal one third to two third portion of the laminae. Due to Ca deficiency, the younger leaves became thick, brittle and reduced in size with blunt end. Light orange yellow chlorosis developed along the leaf margins and tips followed by the development of necrotic spots with bright orange yellow zone adjacent to the necrotic areas. Magnesium deficiency was characterized by the yellowing of the midrib and lateral veins and adjacent areas starting from the base of the leaf followed by yellowing of the entire laminae, necrosis and outward cupping of margins. In the case of S deficiency, the younger leaves became uniformly lemon yellow which later developed characteristic ‘birds eye spot’ and ‘shot holes’. Interveinal chlorosis of the young leaves was the most commonly observed symptom of micro-nutrient deficiencies. However, the chlorosis was specific to the concerned nutrients. Uniform straw yellow discoloration of leaves with pale green midrib and lateral veins followed by development of necrosis from leaf tip towards base, downward cupping of leaves and asymmetrical laminae were the symptoms of Fe deficiency. Manganese deficiency symptoms were characterized by pale yellow interveinal chlorosis and crinkling of leaves. Development of water-soaked spots from margins and tips in a wavy pattern towards the midrib followed by downward cupping, coppery red necrosis and leaf distortion were the characterization symptom of Cu deficiency. Symptoms of Zn deficiency were expressed as abnormally long and narrow leaves with characteristic mottling and reduced internodes. Boron deficiency symptoms were expressed as crinkling and orange yellow chlorosis of leaf tip of younger leaves which were thick and brittle. Later on, bright orange yellow chlorotic patches developed in between the lateral veins followed by the development of necrosis from margins and tips at the distal portion. Cracks developed at the necrotic areas and torn off. Among the macro and micro-nutrients, the earliest deficiency symptoms were manifested by the element Fe (3rd month), followed by Mg and S (4th month) N (5th month) P and B (7th month), K, Cu and Zn (8th month), Ca (9th month) and Mn (9.5th month). Vegetative growth was markedly reduced due to the deficiency of macro and micro-nutrients. Calcium, P, K, Mg and Zn were the elements which showed profound influence on root growth. The growth of plant was found to be completely arrested at a comparatively early stage (5th month) due to Mg, S and Fe deficiencies, followed by B (7th month), N (9th month), P, K, Ca, Cu an Zn (10th month) and Mn (10.5th month) deficiencies. Visual symptoms of deficiencies were concurred with a marked reduction in the foliar level of the concerned element. The influences of macro and micro-nutrient deficiencies on the foliar level of other nutrients are furnished below. Comparative foliar concentration of nutrients Nutrient deficiency --------------------------------------------------------------------- Elements increased Elements decreased Nitrogen P, Zn, B Mg, Fe, Mn Phosphorus N, Zn Mg, Mn Potassium Ca, Mg Nil Calcium K, Mg, N B Magnesium Ca, K, Cu N Sulphur N, P Nil Iron P, Zn, Mn K, Ca Manganese Fe, K, N Nil Copper Fe, Mg Ca Zinc P, Fe Mg Boron N, P Ca, K The deficiency symptoms could be recovered by the application of the deficient nutrient element. The flowering shoots of nutmeg were found to be associated with a significantly higher concentration of carbohydrates in leaves. The flowered shoots had a relatively lower amount of N in leaves prior to flowering and the N content increased slightly towards flowering. It was observed that the P, K, Ca and Mg were higher in the flowering shoots. But the variation was significant only in the case of Ca and Mg, that too in three flushes out of the normal four. The flowering shoots had a relatively lower concentration of foliar S than that of the non-flowering shoots. The flowering shoots registered significantly higher C/N ratio in leaves than that of the non-flowering shoots. The flowered shoots always registered a relatively higher P/S, Ca/S and Mg/S ratios and a lower foliar level of Ca/Mg, N/P and N/K ratios. The flowered and non-flowered shoots showed an erratic trend with respect to K/Ca, K/P and Ca + Mg ratios.ThesisItem Open Access Standardisation of propagation techniques in Phyllanthus emblica Linn.(Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, 1986) Pushpalatha, P B; KAU; Aravindakshan, MThe studies on propagation techniques in Phyllanthus emblica Linn. were carried out in the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara during the year 1984 to 1985. The studies were carried out on seed as well as vegetative propagation. The present series of studies are the first of its kind done in Kerala on the above lines and have yielded valuable results. The stones did not germinate with any growth regulator treatment tried. The hard ‘shell’ covering the seeds acted as a great barrier for seed germination. The seeds are to be extracted and sown to get germination. GA 250 ppm was found to induce the maximum germination of seeds. The growth characters analysed based on the height of seedlings, girth of seedlings and number of leaves produced also revealed the superiority of GA 250 ppm. The seed germination and seedling survival was always high under mist. The conditions prevailed under the mist i.e. an ambient temperatures of 23 to 270 C, soil temperature 20 to 230 C and high relative humidity 98 per cent was found to be the most congenial condition for both seed germination and seedling survival. The germination and survival was enhanced to the maximum when the effect of GA 250 ppm and mist were combined. The seasonal influence on seed germination was negligible while the seedling survival was highest during rainy season. The experiment on seed storage showed that the viability increased after extraction and attained maximum two months after storage. The viability decreased there after and was lost completely seven months after storage. Cloth was found to be a useful material for storing the seeds. Vegetative propagation through shoot cuttings, root cuttings, intact roots, budding and layering were tried. Shoot cuttings failed to root irrespective of the various chemical treatments and conditions provided for rooting. Similarly root cuttings also did not regenerate. But the sucker production from the intact roots could be accelerated by injuring the roots. Out of the four types of roots viz. 3 cm, 5 cm, 7 cm and 10 cm thick roots, 3 cm thick roots proved to be superior in terms of percentage sprouting, vigour and growth. The survival of the sucker after transplanting was also maximum in 3 cm thick roots. Out of the two methods of budding viz. patch and ‘T’ budding, patch budding was found to be significantly superior in terms of sprouting, survival and subsequent growth. Defoliation prior to budding was found to be beneficial for sprouting and growth of buddings. The experiment on air layering indicated that callus formation was confined to the treatment with IBA especially at lower concentrations. The callus so formed, however, did not differentiate into roots.