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ThesisItem Open Access Evaluation of f 1 hybrids resistant to bacterial wilt and inheritance of resistance in brinjal (lolanum melongena L.)(Department of Olericulture, College of Horticulture, Vellanikkara, 1991) Geetha, Varghese; Abdul, Vahab M.The present studies "Evaluation of F hybrids resistant to bacterial wilt and inheritance of resistance in brinjal ( Solanum melongena L . ) were conducted during February 1990 to July 1991in the vegetable research plots of Kerala Agricultural University,Vellanikkara. Evaluation of F hybrids over 4 environments revealed that all the 3 hybr ids were superior to their parents for yield during all the four seasons. It also indicated significant role of genotype x environment interaction in the yielding abi l ity of the hybrids. Considering wilt resistance the hybrids were not superior to their parents. Varietal difference was observed for plant height, fruits/plant, fruit weight, fruiting period and productive flowers. Estimation of heterosis of three F^s over their parents revealed significant heterosis for plant height, days to flower, days to first fruitset, days to harvest, primary branches/plant, total fruits/plant, total yield/plant, average fruit weight and fruiting period. All the three hybr ids viz. Surya x Pant Rituraj, SM 6-6 x SM 132, SM 6-2 x Pusa Purple Cluster were stable. Study on the nature of inheritance showed that resistance to bacterial wilt is inherited in a recessive and monogenic manner.ThesisItem Open Access Studies on fertility status of rubber growing soils of Palakkad district(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1991) Mohanan, V; KAU; Nazeem, P AThesisItem Open Access Development of a suitable model for ascertaining the growth and egg production in quails(Department of Agricultural Statistics, College of Horticulture, Vellanikkara, 1991) John Thomas, M; KAU; George, K CAn investigation was carried out into the growth and egg production aspect of Japanese quails at the Kerala Agricultural University Poultry Farm, Mannuthy on 1st February, 1989 with the following objectives. 1. to find a suitable relationship between age and body weight. 2. to investigate the" trend of egg production in quails through suitable mathematical models. ,3. to study the impact of climate parameters (temperature, ; , humidity) on egg production in quails. The birds were reared under uniform feed formula and ^identical management practices (recommended by Kerala Agricul tural University Package of Practices). The investigation mainly depended on' data consisting of weekly body weights of -ii^-dividual birds, daily egg production of birds (beginning from age at sexual maturity) and daily climatological para meters (temperature and humidity) from beginning till the end of experiment of 30th September, 1989. Mathematical models such as linear, quadratic, exponential, .Von-Bertalanffy, modified exponential, logistic and Gompertz were fitted for the purpose using body weights of ) individual birds as well as average body weights over twelve weeks and the fitted models were compared using coefficient of 2 determination (r ) and standard error of estimate(s). Mathematical models such as linear, exponentialf parabolic exponential, inverse polynomial. Gamma function. Gamma-type functic^n, quadratic function, quadratic function in logari'thmic scale, quadratic-cum-log, emperical and linear hyperbolic functions were fitted for the development of suitable models for ascertaining egg production using total weekly, fortnightly egg production, hen housed and hen day egg production and fitted models were compared using Furnival index, r^ and s. Multiple linear regression equation was fitted using average weekly egg production per bird as dependent variable and weekly temperature and humidity as explanatory variable to study the impact of climatological parameters on egg production in quails. The investigation has the following, salient features. (i) The hatching weight of Japanese quails were 7.1369 g. (ii) The females weighed more than the males during the entire period of experiment and the body weights have shown an increasing trend. At the end of 12th week the average body weights of males and females were 157.6552 g and 179.2500 g respectively. (iii) Rao's method justified that initial body weights • had no significant effect on growth rate. • (iv) Gompertz curve = a exp [-b exp(-kt)'] was most , suitable for , ascertaining growth in quails on individual basis as well as on the basis of • average body weights over twelve weeks. (v) Average age at sexual maturity (females) was found to be approximately 10 weeks and on an average the eggs weighed 12.20 g. (vi) Quadratic function in logarithmic scale ; = a f b(logJ^) + c(log^)^ was most suitable , for ascertaining egg production in quails (weekly, , fortnightly, hen housed and hen day production • basis). (vii) Climatic parameters had significant impact on egg production in quails.ThesisItem Open Access Evaluation of selections and hybrids of Vetiver (Vetivena zizanieides (Linn ) Nash)(Department of Agricultural Botany, College of Horticulture, Vellanikkara, 1991) Radhakrishnan, G R; Viswanathan, T VThesisItem Open Access Stand density manipulation and fertilization studies on teak(College of Forestry,Vellanikkara, 1991) Gawande, S R; Mohankumar, BWith the object of standardizing the density manipulation and fertilization strategies for teak, a study was carried out at Vellanikkara during 1990-91. The experimental variables consisted of high, medium and low site quality classes (classified on basis of tree heights), three thinning intensities (control, 30 per cent density reduction and 50 per cent density reduction) and three fertilizer levels (control, 50:25:25 kg of N, P2 O5 and K2O ha -1 yr-1, 100: 50:50 kg of N, P2 O5 and K2O ha-1 yr-1). The results indicate that mean height of trees was strongly influenced by density manipulation. The combination of high site quality with medium and heavy fertilizer doses also significantly increased the mean height of trees. However quadratic mean diameter, stand basal area, basal area increment and height increment were not substantially different among the thinning site quality and fertilization regimes. Tree biomass, foliage area and leaf weight allometry were examined for the first time in teak. The results suggest that leaf area and the biomass yield are strongly dependent on the allometry of trees. High sites consistently recorded higher values for estimates of leaf area, leaf biomass and tree biomass. Combinations of high site quality with medium and heavy thinning as well as medium and heavy fertilization recorded high tree biomass yield, foliage area and leaf area followed by medium and low site quality classes. Foliar analyses showed a general increase in leaf nitrogen during summer (May) and a gradual decline of the same during the fall season (August). High site quality with medium and heavy fertilization recorded highest nitrogen content. Thinning on higher sites significantly increased foliage phosphorus and potassium levels. In general the trend concerning nutrient contents of different tree organs followed the order leaves> stemwood> branchwood. Branch wood and stem wood N levels were relatively higher on high sites. Potassium content was, however, greatest in the low sites. Soil nutrient analysis did not indicate any substantial changes in the soil physico-chemical properties consequent to thinning and fertilization which incidentally substantiates Miller’s hypothesis on forest fertilization that fertilizers benefits only the trees and not the sites.ThesisItem Open Access Induced chemical mutagenesis in Rose under in vitro culture(Department of Agricultural Botany, College of Agriculture,Vellayani, 1991) Uma, B; KAU; Krishnan Nair, NThe present investigation entitled “Induced chemical mutagenesis in rose (Rosa chinensis) under in vitro culture” was carried out in the Tissue Culture Laboratory attached to the Horticultural Department, College of Agriculture, Vellayani during 1989-90. The main objectives of the experiment were to standardize a suitable culture medium for the growth and development of axillary buds and to standardize a successful method of chemical mutagenesis in rose under in vitro culture using the most potent chemical mutagen, ethyl methane sulphonate. The standardization of hormone levels in the culture medium (ms) was done at three stages of explant development viz. culture establishment, axillary bud proliferation and in vitro rooting. Surface sterilization of axillary buds were standardized by using mercuric chloride selecting out three concentrations 0.06, 0.08 and 0.1 per cent and 3 periods of treatment 5, 10 and 15 minutes. The axillary buds used were of 4 maturity stages ie. Axillary buds at the time of flower harvest and 2, 4 and 6 days after flower harvest. The various concentrations of ethyl methane sulphonate tested include 0.125, 0.25, 0.375 and 0.5 per cent. Two methods of mutagen treatments were tried ie. direct treatment and cotton swab method. In the direct treatment the axillary buds were subjected to EMS treatment at different periods treating the buds at the time of culturing, 2 days after culturing, 4 days after culturing and 6 days after culturing. In the cotton swab method buds were treated with EMS in the plant itself at various stages ie. at the time of flower harvest and 2,4 and 6 days after flower harvest. Surface sterilization of axillary buds was found to be most successful with mercuric chloride at 0.08 per cent for 15 minutes of the various levels of hormonal combinations tested BAP 2 mg/1 +2.4-D 1 mg/1 was found to be the best for culture establishment and BAP 2 mg /1 +GA 1mg/1 for shoot proliferation. Maximum rooting was obtained in full strength MS medium supplemented with IAA 2 mg/1 of the two methods of mutagen treatments tried direct treatment of axillary buds with EMS was not found to be effective as the buds turned brown and no further development occurred. In the cotton swab method, lower concentrations of EMS (0.125 and 0.25 per cent) gave a better performance based on days taken for bud take multiple shoot production and rooting percentage. A decrease in survival percentage was noted with increase in mutagen concentration. Higher concentration of EMS (0.375 and 0.5 per cent) curbed multiple shoot production in buds excised at the time of flower harvest and delayed multiple shoot production in other stages. The percentage cultures showing rooting and the number of roots/shoot also decreased with increase in concentration of EMS. Increase in maturity of buds also delayed multiple shoot production and decreased rooting percentage of the 4 stages of buds used for in vitro culture, buds excised at the time of flower harvest was found to be the best. But mutagen treatment retarded their performance. For mutagen treatment buds excised 4 days after flower harvest was found to be best followed by buds excised 2 days after flower harvest. Buds excised 6 days after flower harvest showed a poor performance in the normal and treated populations. The experiment clearly demonstrated that induced mutagenesis in rose can be successfully done adopting in vitro culture techniques.ThesisItem Open Access Genetic analysis of productivity parameters in horsegram(Department of Plant Breeding, College of Agriculture,Vellayani, 1991) Elizabeth, Mathew; Ramachandran Nair, NA study on the parameters of variability, correlation and path coefficient were undertaken in forty eight horsegram varieties. The study was conducted at the Department of Plant Breeding, College of Agriculture, Vellayani during Rabi 1989. The varieties showed significant differences in all the characters studied. Genotypic coefficient of variation was maximum for days to flowering and minimum for length of pod. High heritability estimates were observed for hundred seed weight and days to flowering. Genetic gain was maximum for days to flowering. Hundred seed weight and days to flowering recorded high heritability and high genetic gain indicating the presence of additive gene action. At the genotypic level seed yield showed high positive correlation with harvest index and number of pods per plant. Path coefficient analysis projected number of pods per plant, length of pod and number of branches as the traits exerting high positive direct effect on seed yield. The study indicated that the model for plant selection in horsegram should be one with more number of branches, long pods and more number of pods per plant. The varieties P. Palayam, CODB-1, Calicut local, PLS-6056 and No.447 were found to fit in this model.ThesisItem Open Access Social behaviour, dominance hierarchy and reproductive behaviour of sambar deer (cervus unicolor)(College of Forestry,Vellanikkara, 1991) Krishnakumar, Kumar; R, KAU; Jacob Cheeran, VA study was undertaken to investigate the social behaviour, dominance hierarchy and reproductive behaviour of sambar deer in captivity, mainly with the intention of evaluating the adaptability of the species to captive breeding. This study was conducted on the population of sambar deer in captivity at Trichur and Trivandrum zoos. Behavioural observations were made during a period spanning five months totally – from November – December 1988 to April – May 1989, on days at random. There were 21 deer in the herd at Trichur and 20 at Trivandrum. It was observed that the living conditions of the deer in these zoos are far from comparison to that of their natural habitats. Food, herd size, competition, nearest neighbour relationship etc: are strikingly different from nature. But, in spite of all adversities, the sambar deer have learned to adapt amazingly to changing conditions, and survive fairly well. The physiological processes of their lives, such as antler casting, rut, mating, gestation and delivery remain as scheduled, except for observations that births occur at any time of the year in captivity sometimes, which is in effect to the advantage of the captive -breeder ! Maintenance of ideal herd composition at any given time would help better the living conditions as well as curtail traumatic injuries and casualties. Paucity of adequate space is a serious constraint faced by these zoos. It is time that voluntary organisations and individuals came forward with earnest interest in the upkeep of zoos as in foreign countries ; rather than leaving the whole show in the sole hands of the government as the present practice. General awareness and overall change in the attitude of the public towards our vanishing wildlife is the need of the hour.ThesisItem Open Access Effect of chitin synthesis inhibitors on rice swarming caterpillar spodoptera mauritia and rice moth corcyra cephalonica and a larval parasitoid bracon brevicornis(Department of Agricultural Entomology, College of Agriculture, Vellayani, 1991) Prathapan, K D; KAU; Dale, DEffects of four chitin synthesis inhibitors viz. diflubenzuron, chlorfluazuron, PH 70-23 and BASF LAB 153 959 I were assessed on two insect pests, the rice swarming caterpillar Spodoptera mauritia ( Boisduval) and rice moth Corcyra cephalonica (Stainton) and on its larval parasitoid Bracon brevicornis (Wesmael). Ovicidal action was assessed by treating one and two-day old eggs of S. mauritia in aqueous and mathanilic media. It was low in aqueous medium. But in methanolic medium diflubenzuron and the highest doses of the other three compounds showed enhanced action. In general, high ovicidal action was observed in methanolic medium. There was no significant difference between one and two-day old eggs in their susceptibility to chitin synthesis inhibitors. Chlorfluazuron was the most toxic causing cent per cent mortality at doses as low as 2 x 10 -5% when treated on second and fifth instar larvae of S. mauritia. Diflubenzuron, PH 70-23 and BASF LAB 153 959 I were also highly effective. Second instar larvae were more susceptible than fifth instar ones. Besides stomach action, a high degree of contact action was also observed. Final instar larvae of S. mauritia when treated with the test chemicals, produced larval-pupal intermediates and caused pupal mortality and emergence of deformed adults. All the four moult inhibitors were highly active during larval – pupal transformations. Pupae were less susceptible to chitin synthesis inhibitors. Yet, some treatments caused mortality and emergence of deformed adults. Chlorfluazuron was the most toxic to pupae. Fecundity, hatchability of eggs and longevity were reduced when the male moths of S. mauritia were fed on sugar solution containing the moult inhibitors. Antifeedant action of the chitin synthesis inhibitors was found to be less pronounced. Residual effect of all the four compounds persisted on the treated rice foliage throughout a study period of 36 days. But the efficacy of residues exposed to sunlight and rain was very low. Ovicidal action of the moult inhibitors was low to moderate on one and four-day old eggs of C. cephalonica in aqueous medium. In methanolic medium diflubenzuron at 2 x 10 -1 %, 2 x 10 -2 % and 2 x 10 -3 % and PH 70-23 and BASF LAB 153 959 I at 2 x 10 -1 % caused enhanced ovicidal action. In general there was no significant difference between the susceptibility of one and four-day old eggs. Chlorfluazuron was found to be the most toxic compound against larvae of C. cephalonica followed by BASF LAB 153 959 I. Diflubenzuron and PH 70-23 were less effective. Early larval instars were more susceptible. Contact action of compounds other than chlorfluazuron was low. Larval – pupal intermediates, pupal mortality and emergence of deformed adults were resulted when the last instar larvae of C. cephalonica were treated with the chemicals. Chlorfluazuron was found to be the most toxic compound. Prepupal treatment also caused the above juvenomimetic effects. But treatments other than chlorfluazuron 2 x 10 – 2% were less effective. Treatment of pupae of C. cephalonica resulted in pupal mortality and emergence of deformed adults. But pupae were less susceptible to the moult inhibitors as compared to the larval stages. External application of Chitin synthesis inhibitors to moths of C. cephalonica had no adverse had no adverse effect on fecundity, hatchability of eggs and longevity of the treated moths. Chlorfluazuron was found to inhibit the emergence of adult parasites from treated hosts and adversely affect the progeny production of B. brevicornis. Diflubenzuron, PH 70-23 and BASF LAB 153 959 I were non-toxic or only slightly toxic to the parasite.
