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ThesisItem Open Access Studies on the performance of two groundnut varieties, TMV-2 and TMV-9, under graded doses of phosphorus and potassium.(Department of Agronomy, College of Agriculture, Vellayani, 1978) Purushothaman Nair, N; KAU; Sadanandan, NThesisItem Open Access Study on adoption of soil conservation measures by farmers in scheme areas of Trivandrum District(Department of Agricultural Extension, College Of Agriculture, Vellayani, 1978) Balakrishna Pillai, G; KAU; Nair, G TThe magnitude of the problem of soil erosion is so high in Kerala mainly due to the undulating topography and high intensity of rainfall. More than 10 lakhs hectares of undulating land have to be protected from the hazards of erosion by effective soil conservation measures . The results of studies conducted on the soil loss by the soil conservation station. Konni has shown that the soil loss where slope was 30 per cent was 241.56 tonnes per acre per year. Attempts are made to control the serious loss of top soil by the Department of Agriculture (Soil Coservation Unit) by implementing integrated soil conservation schemes. But the progress of coverage was poor. Even in scheme areas, many farmers are non -adopters of the required soil conservation works. Many farmers have not taken up the required Agronomy and Agrostology works eventhough theycompleted the contour bunding works. A detailed study was essential to understand all those aspects of adoption . This study was an effort in that direction.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 Foliar diagnosis, yield and quality of ginger(zingiber officinale ROSCOE) in relation to nitrogen, phosphorus and potassium(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 1978) Johnson, P T; KAU; Jose, A IA field experiment was carried out at the Instructional Farm, attached to the College of Horticulture, Vellanikkara during 1977 – 78 to study the effect of graded doses of nitrogen, phosphorus and potassium on the growth, yield and quality of ginger and also to develop suitable foliar diagnosis techniques in relation to these nutrient elements. The treatments comprised of three levels each of nitrogen (40, 80 and 120 kg N/ha), Phosphorus (30,60 and 90 kg P2 o5/ha) and potassium (40,80 and 120 kg k2o/ha). The experiment was laid out in a 33 factorial experiment in randomised block design confounding the affect of interaction NP2K2 totally. The results revealed that among the morphological characters studied, only the height of tiller and total dry matter of the plant were markedly influenced, while other characters like number of tillers and number of leaves per tiller were not effected. Of the fertilizer treatments, nitrogen at 80 kg/ha significantly affected these two characters, while the effect of phosphorus and potassium were not significant. Application of nitrogen at 80 kg/ha significantly increased the rhizome yield of the crop, while the levels of phosphorus and potassium employed failed to influence the yield. Uptake of nitrogen and phosphorus by the plant was significantly influenced by the application of nitrogen at the rate of 80 kg/ha, whereas the graded doses of phosphorus and potassium had no significant influence in this respect. The uptake of potassium on the other hand was not influenced by any of the fertilizer treatment introduced. The total period of growth put under observation appeared divisible into three phases with respect to the development of aerial tissues namely, a phase of active vegetative growth (90th to 120th day after planting); a phase of slow vegetative growth (120th to 180th day) and a phase approaching senescence (180th day to harvest). The pattern of the rhizome development followed the same trend as that of the aerial tissue, but instead of a final phase of insignificant growth, the development of rhizome continued till harvest. The uptake of nitrogen, phosphorus and potassium progressively increased with advancing period of group growth. There was marked uptake of these nutrients by the plant during the period of active plant growth (90th to 120th day after planting). The uptake of nitrogen, phosphorus and potassium in leaf and pseudostem progressively increased upto 180th day and then decreased while their uptake in rhizome steadily increased till harvest. The content of nitrogen phosphorus and potassium was highest in the top most leaves and continuously decreased with increasing number of the leaf position, when the leaves are numbered from top to bottom of the tiller. In consideration of the stability of nutrient level with leaf positions and sensitivity or correlation with varying doses and uptake, the group of 5th to 12th leaves appeared to be the best suited for foliar diagnosis of N, P and K status of the crop. The period between 90th to 120thday after planting was recommended as the optimum period for the detection and amendment of the nutrient status of the crop. The graded doses of nitrogen, phosphorus and potassium and their interaction failed to influence the percentage oleoresin content of ginger.ThesisItem Open Access Morphological studies and quality evaluation of turmeric types(Department of Horticulture (Plantation Crops), College of Horticulture, Vellanikkara, 1978) Joseph, Philip; KAU; Sivaraman Nair, P CA study using 19 turmeric 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 possibility of distinguishing different types based on morphological parameters, to screen out the types with high yield and quality, to evaluate their relative susceptibility or tolerance to important pests and diseases and to study the yield and quality variations at different periods of maturity. The study revealed that morphological characters are not reliable to classify the turmeric types, although some of them can be distinguished by rhizome characters. The morphological characters such as the height of plant, length and breadth of leaf, leaf area index, petiole length, number of leaves per tiller, number of roots per plant, length of root, length of primary fingers and girth of mother rhizome were positively correlated with yield, whereas the intensity of shoot borer attack was negatively correlated with yield. All the types were susceptible to the incidence of ‘leaf spot’, ‘leaf blotch’ and shoot borer infection. The type VK5 (Mannuthy Local) showed the minimum incidence of pest and diseases. The yield of turmeric showed significant variation among the types. Maximum yield of green turmeric was noticed in the type VKI (Chayapasupa) whereas the type VK5 (Mannuthy Local) recorded the maximum yield of cured produce. Significant variation was noticed among the types with regards to the oleoresin and curcumin content. The oleoresin content varied between 12.1 and 21.1 per cent and the variation in curcumin content was from 2.33 to 6.55 per cent. The uncured turmeric samples had a higher content of oleoresin and curcumin than that of cured samples. The yield, percentage recovery of dry produce, oleoresin and curcumin varied significantly among the different periods of maturity in case of the types VK4 (G.L.Puram-II), VK5 (Mannuthy Local), VK17 (Armoor Cll-324) and VKII (Vontimitta). The dry yield, curcumin and oleoresin per hectare were maximum on 270th day whereas the maximum percentage recovery of oleoresin was on 180th and 270th day after planting. The types VK5 (Mannuthy Local), VK1 (Chayapasupa), VK2 (Kuchupudi) and VK3 (Kodur) can be recommended for large scale cultivation in the plains of Kerala as these types are found to be superior in yield of dry produce, oleoresin and curcumin per hectare. Of these VK5 (Mannuthy Local) and VKl (Chayapasupa) are preferred because of the low incidence of pest and diseases. The optimum time of harvesting turmeric is found to be on 270th day after planting under Vellanikkara conditions.ThesisItem Open Access Genetic variability and correlation studies in snake gourd (crichosanthos anguina L.)(Department of Olericulture, College of Horticulture, Vellanikkara, 1978) Joseph Pynadath, S; KAU; Gopalakrishnan, P KStudies were undertaken with 25 diverse snake gourd types in the Department of Horticulture (Olericulture), College of Horticulture, Vellanikkara, to estimate the genetic variability, correlation coefficients and path coefficients in the crop, during 1977-78. The results have shown that the differences between the types were highly significant for all the 21 characters studied. The estimates of variance components and coefficients of variation have indicated that the major portion of total variability in most of the characters was due to genetic causes, heritabllity in the broad sense was found to be quite high for most of the characters but the heritabllity estimate of yield was only 45.90 per cent. The estimate of genetic gain has shown that by selecting five per cent superior plants from the available population, yield can be improved upto 35.66 per cent over the mean. Characters such as per cent ash content, crude protein per cent, percentage P, number of female flowers per plant, weight of individual fruit and vitamin C content which exhibited parallelism in the high estimates of heritabillty and genetic gain may be suggested to be due to the action of additive genes and can be straightly improved through selection. The type T.A.19 was found to be the highest yielder. Yield per plant was found to be highly associated with number of primary branches, days for opening of first female flower, weight of individual fruit, length of fruit and girth of fruit. The correlation coefficients among these yield components were also significant. Path coefficient analysis has shown that weight of individual fruit, girth of fruit, number of fruits per plant and node at which first female flower appeared are the more important characters contributing to yield, on account of their high direct effects. Number of female flowers per plant and length of fruit are also important characters as their direct effects were moderate and indirect effects substantial.ThesisItem Open Access Genetic variability, correlation studies and path coefficient analysis in bittere gourd (Momordica Charantia L.)(Department of Olericulture, College of Horticulture, Vellanikkara, 1978) Ramachandran, C; KAU; Gopalakrishnan, P KStudies were undertaken with 25 diverse bitter gourd types in the Department of Horticulture (Olericulture), College of Horticulture, Kerala Agricultural University, Vellanikkara, Trichur, to estimate the genetic variability, correlation coefficients and path coefficients, and also to formulate a reliable selection index for the crop, during 1977-78. The results have shown that the differences between types were highly significant for all the twenty one characters studied. The estimates of variance components and coefficients of variation have indicated that the major portion of total variability in all characters, except number of seeds per fruit, was due to genetic causes. Heritability in the broad sense was found quite high for all characters except number of seeds per fruit. Expected genetic advance has shown that, by selecting five per cent superior plants from the available population, yield could be improved by 4.08 kg per plant. Characters such as yield per plant, vitamin C content, number of fruits per plant, number of female flowers per plant, iron content and phosphorus content which exhibited parallelism in the high estimates of heritability and genetic gain may be suggested to be due to the action of additive gene and can be straightly improved through selection. Type B.G.23 was found to be exceptionally high yielding. Yield per plant was found to be highly correlated with length of main vine, weight of fruit, length of fruit, number of fruits per plant, number of female flowers per plant and number of primary branches per plant. The correlation coefficients among these yield components were also highly significant. Path coefficient analysis has shown that the weight of fruit, number of fruits per plant and length of main vine had high direct positive effects on yield. Number of primary branches per plant, number of female flowers per plant and length of fruit exhibited low and negative direct effects on yield. Multiple regression analysis resulted in fitting a function, indicating that, about 74 per cent of the fruit yield in bitter gourd could be predicted phenotypically, if the observed value for length of main vine is multiplied by 0.8990, number of fruits per plant by 0.0492 and weight of fruit by 0.0335 and from their sum of products 7.2168 is subtracted.ThesisItem Open Access Quick wilt disease of pepper (Piper nigrum Linn)-1 symptomatological studies on the quick wilt disease of pepper(Department of Plant Pathology, College of Horticulture, Vellanikkara, 1978) Mammootty, K P; KAU; Abi CheeranThe present study on the quick wilt disease of pepper caused by Phytophthora palmivora (Butler) Butler was conducted at the Pepper Research Station, Vellanikkara using Panniyoor-1 pepper variety. The objectives of the investigations were to study the symptoms of the disease and to find out suitable control measures using fungicides. The first visible symptom on leaf, stem and root was noticed 24 to 48 hours; two to five days and 24 to 48 hours respectively after inoculation, depending on the maturity of the plant part. A fully developed lesion had a dark brown hononecrotic centre and plesionecrotic boarder surrounded by yellow halo. The yellow halo was not noticed during prolonged wet and humid conditions. Under these conditions lesions was uniformly brown in colour. Zonations were noticed during the alternate wet and dry conditions. On the stem, branches and roots symptom usually developed as a uniformly brown and dark coloured lesions. Pathogen entered mainly though lower surface of the leaf. After infection, defoliation took place within five to ten days. Development of flaccidity, drooping and defoliation of the leaves were the marked symptoms during the progress of disease when the stem, branches or roots were infected. All the fungicides tested checked the growth of the fungus in vitro for a period of three days. The fungicides when sprayed or drenched two hours before inoculation completely checked the disease. However, there was mild infection on plant where Dithane M-45 was used for drenching the soil. As the interval between the fungicidal spray and inoculation prolonged there was progressive reduction in the control of the disease. None of the fungicides was able to eradicate completely the established pathogen on leaves. When fungicides were applied one day after inoculation there was complete control of the disease on stem. While the control was not complete when it was applied two days after inoculation. All the fungicides except Dithane M-45 completely checked the development of the disease when they were drenched in soil.ThesisItem Open Access Studies on the granulosis virus of Pericallia ricini Fabricius (Arctiidae: Lepidoptera)(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1978) Babu, M Philip; KAU; Abraham, JacobThe black headed hairy caterpillar, Pericallia ricini Fab., is a polyphagour pest feeding on a wide variety of crops such as castor, cotton, banana, cucurbits, sunflower, field beans, and gingelly. The occurrence of a granulosis in this insect was recorded in 1972, but no detailed studies have so far been made on this disease. A through knowledge of the disease including the host pathogen relationships and the physico-chemical properties of the pathogen is essential to judge its suitability in practical pest management programmes. With a view to collect these information the present studies were taken up. Studies were made in the laboratory and in field cages. Larvas of P. ricini reared in the laboratory on castor leaves were used. Third instar larvas were used in all studies except those on symptamatology and larval susceptibility. A purified suspension of granules derived from 300 dead larvae in 3 litres of distilled water formed the inoculam. All the experiment were conducted at room temperature and humidity.
