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ThesisItem Open Access Pattern of growth in domestic fowl(Department of Statistics, College of Veterinary,Mannuthy, 1981) Jacob Thomas, M; KAU; Surendran, P UUnder uniform feed formula and identical management practices, 30 Australorp (ALP) males, 26 (ALP) females, 25 white Leghorn(WL) males and 31 (WL) females, were reared for 24 weeks in Kerala Agricultural University Poultry Farm, Mannuthy to study their growth patterns. The initial mean body weights of chicks were 35g. for ALPmales, 34.4615g. for ALP females, 33.04g for WL males, 32.0645g. for WL females. Throughout the experiment males in each genetic group had a higher mean weight than females. A plateau on the body weight was reached by the end of 23 weeks in almost all birds, indicating that 24 weeks completely covered the growth period. By the end of the experiment the mean body weight was 1858g for ALP males, 1488.4615g. for ALP females, 1556.8g. for WL males, 1306.1290g for WL females. Though there was no significant difference between the groups at the end of the fourth week, significant differences between pairs were observed after 16 weeks. Exponential (y =aebx), Gompertz (y = abcx) and Logestic (105/y = a + bcx) curves were found to be suitable for fitting body weights for 24 weeks. The first two gave extremely good fit. Modified exponential was good only for data of twelve weeks. When growth rates for twenty four weeks were compared on the basis of the fitted curves for all birds the conclusion arrived at was the same for exponential and Gompertz curves. The rates of growth for ALP males, WL males, ALP females WL females and were in the descending order of magnitude; they were significantly different. Same was the inference obtained when Rao’s method of comparing rates of growth was adopted. The result obtained for comparing the rates of growth by fitting Exponential and Modified exponential for the body weights of birds for 12 weeks were similar. Both the curves gave very satisfactory fit to the data. The coefficient of correlation between the observed and expected body weights was nearly unity in almost all cases.ThesisItem Open Access Pattern of development of shank length in chicken(Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1982) Indirabai, T K; KAU; Surendran, P UShank length and body weight measurements on 30 male and 30 female chicks from each of White Cornish (WC) and White Plymouth Rock (WR) breed were utilized to study the pattern of development of shank length in chicken. The birds were reared for eight weeks in Kerala Agricultural University Poultry Farm under uniform management. Upto the end of three weeks uniformity could be seen in the pattern of growth of shank length of the four groups. Thereafter WR male had a lead over the rest. The growth pattern of body weight was not uniform in the groups from the beginning. At the end of eight weeks the growth pattern was found to differ between sexes and breeds. Uniformity in growth rates was found in females of the two genetic groups as also between WC male and WR female. All the other pairs were heterogeneous. High correlation between body weight and shank length revealed that longer shank length can be made a criterion for selection for higher body weight. Shank length at the end of the first week was found to be most suitable for this purpose. Shank length has high positive correlation with age. The method of comparison of growth rates recommended by Rao (1958) was found unsuitable for the present study. Among the functional forms examined Modified Exponential, Gompertz and Logistic were found to be unsuitable for expressing shank length as a function of age. Most suitable patterns for expressing shank as a function of age in weeks were found to be linear and exponential. Among these two exponential turned out to be better than the other.ThesisItem Open Access Determination of the size and shape of plots for trials on cashew(Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1981) Remesh, B Nair; KAU; Prabhakaran, P VThe present study whose objective is to evaluate the problems concerned with field experimentation on cashew was undertaken using the yield records of 625 uniformly treated cashew trees collected from cashew research station, Madakathara for a period of five years starting from 1976. A single row of trees was discarded on either side of the experimental field to eliminate border effect. Thus the experimental material consisted of 576 trees raised from same parental stock in a 24 x 24 compact block arrangement. The period 1976 to 1980 for which there was no change in treatment was considered to be the pre-experimental period and the year following the application of treatment was considered to be the experimental period. Observations on certain yield contributing characters pertaining to the year 1978 to 1979 such as height, spread and trunk girth were also gathered. Plots of different sizes and shapes were formed by combining yields of adjoining trees in various possible ways, a single tree being considered as the ultimate unit. The plots were grouped into blocks of different sizes and cv was worked out for plots of different dimensions when plots were arranged in blocks and not arranged. The trees were found to be highly heterogenous even though they were raised from the same parental stock. Single tree plots were found to be the most efficient when viewed from the point of view of maximum relative percentage information and consequently could be recommended for conducting field experiments on cashew. Two tree plots could also be recommended due to certain practical considerations shape of plot did not seem to have a consistent effect on variability. Fair field Smith’s equation gave a good fit to the data and the parameter ‘b’ was found to be high in both the cases when trees are arranged in blocks and when they are not arranged. It was observed that 2 plot blocks were the most efficient for conducting field experiments on cashew. The efficiency of blocking decreased with an increase in plot size. The result showed that experimental error could be considerably reduced by the use of incomplete block designs. As an effective method of controlling tree to tree variation the method of ranking based on their past performance can be adopted. Efficiency of local control was considerably increased by ranking of trees as compared to mere grouping of trees with respect to their geographical contiguity. Pre-experimental year’s yield was found to be the most important yield contributing character. Trunk girth of tree was also found to have significant influence on the inherent yielding ability of the trees. A selection index evolved was found to be strongly correlated with experimental yield. The correlation coefficient observed for this variate was higher than that for other yield contributing characters. Maximum efficiency in analysis of covariance was noted by using selection index as covariate. Efficiency of covariance analysis decreased with an increase in plot size. The optimum pre-experimental period for calibration and covariance analysis was found to be two year’s immediately prior to the start of the experiment.ThesisItem Open Access Weather paddy crop relationship(Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1981) Krishnan, S; KAU; Surendran, P UAn effective regression method for the examination of the stability of the treatments in repeated experiments was introduced by Finlay and Wilkinson (1963). A new justification for the employment of this method was evolved and this does not require the logarithmic transformation of the data to induce linearity of regression. A treatment has greater than average, average or less than average stability according as the regression coefficient b 1. The data from permanent manorial trials conducted at Rice Research Station, Pattambi from 1973 to 1979 were used to show that the method of regression coefficients to study stability and the method of analysis of groups of experiments are equivalent. This was the first attempt in that direction. Method of analysis of principal components was used to suggest a new weather index based on rainfall and temperature which are considered to be important weather para meters. The number of wet days did not have any significant correlation with the mean yields of treatments. In the kharif season mean daily humidity was significantly correlated with the yield. Whereas all other parameters such as mean daily rainfall, mean daily temperature, mean daily maximum temperature, mean daily minimum temperature, maen daily maximum humidity, mean daily wind velocity and mean daily hours of sunshine did not have any significant correlation. In the rabi season mean yield of Jaya had a correlation of -0.5713 with the mean daily temperature, 0.91131 with mean daily maximum temperature, -0.6802 with mean daily minimum temperature -0.5888 with mean daily minimum humidity and 0.88193 with hours of sunshine. A modified procedure was suggested to estimate the weekly rainfall of a place. This was obtained by applying the method of Surendran et.al. (1977) to logarithms instead of the weekly annual rainfalls. Incidentally it gave a method for suggesting the adequacy of the length of the date for estimation. Theoretical distribution of the weekly rainfall at Pattambi were indicated. All of them were found to obey beta distribution.ThesisItem Open Access Optium plot size for field experiments on brinjal(Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1981) Hariharan, V; KAU; George, K CA uniformity trial in brinjal (Solanum melongena L.) was conducted at the Main Campus of the Kerala Agricultural University, Vellanikkara during the third crop season, 1980. Observations on yield, number of fruits, primary branches and height of each plant was recorded at time of harvest in small units each of size 1.08m2 (2rows x 2 plants at 60 x 45 cm spacing). The variability of each plot size and shape was determined by calculating the coefficient of variation. It was observed that an increase in the plot size in either direction decreased the CV. But the decrease was more rapid along N-S direction. Long and narrow plots yielded lower CV than approximately square plots. The observed relation between plot size and variance was in conformity with the Fairfield Smith’s variance law. At larger plot sizes, the regression line showed a tendency to curve down although negligible. The optimum plot size observed through Smith’s method and maximum curvature method was almost the same. From the above considerations, a plot size of 8.64 m2 (9.6m x 0.9m) was found to be most advisable for conducting most of the field experiments in brinjal. The efficiency of the plot decreased as the size of the plot was increased. There is a general decrease of block efficiency with increasing block size. More compact blocks of the same size show a higher efficiency. Blocks laid out perpendicular to the direction of fertility gradient removed largest variation. The number of replications and total area of land required to give 5% SE of the mean were calculated for the same number of plots per block smaller plots require more replication but less total area than larger plots. But increasing the number of replication rather than plot size was found more advantageous for a fixed experimental area. The fertility contour map of the field revealed that the land is not very homogeneous as far as the fertility pattern is concerned. By assuming arbitrary values of the cost proportional to the number of replications and the cost proportional to the total area per treatment, the optimum plot size for field experiments in brinjal was computed using a linear cost function.ThesisItem Open Access Comparison of different techniques for the estimation of genotype-environment interaction(Department of Statistics, College of Veterinary & Animal Sciences, Mannuthy, 1984) Laly John, C; KAU; Gopinathan Unnithan, V KThe genotypic stability analyses of Eberhart and Russell (1966), Perkins and Jinks (1968), Freeman and Perkins (1971), Wricke (1966) and Shukla (1972) were studied in detail. The mistakes in the analysis of variance of Perkins and Jinks (1968) were corrected. The first three analyses which used the theory of regression explains a large part of the genotypic environment interaction. On the otherhand, when the regression cannot explain a large part of the genotype - environment interaction, Wrioke's ecovalence ratio and Shukla's stability variance could satisfactorily be used.ThesisItem Open Access Optimum plot size for field experiments on turmeric (Curcuma longa L)(Department of Statistics, College of Veterinary & Animal Sciences, Mannuthy, 1984) Gopakumaran Nair, B; KAU; Prabhakaran, P VA uniformity trial on turmeric (Curcuma Longa. L.) was conducted at the experimental field of College of Horticulture, Vellanikkara, during the period from June 1983 to January 1984 to assess the nature and magnitude of soil heterogeneity of the experimental field, and to determine the optimum size and shape of experimental plots and blocks in conducting field trials on turmeric by different methods. At the time of harvest, the yield data from 864 plots each of size 0.6m x 0.75m were recorded separately, discarding the external border row.ThesisItem Open Access Pre-harvest forecasting of sugarcane yield(Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1984) Alphi Korath; KAU; Prabhakaran, P VSeveral yield prediction models were tried to examine their suitability for the pre-harvest prediction of yield of two varieties of sugarcane namely CO-997 and CO-62175 in different months of plant growth using biometric characters based on the data collected from the Sugarcane Research Station, Thiruvalla. The methods of multiple regression analysis, path coefficient analysis and principal component analysis were used for the above purpose. Multiple regression analysis using plant biometric characters revealed that cane yield could be predicted on the basis of observations on height of the cane, girth of the cane find estimated total leaf area per cane or area of third leaf from the seventh month after planting onwards with an accuracy in the range of 59*5 to 81.9 per cent. The estimated cane yield when multiplied by the number of canes in the plot will give an advance estimate of the plot yield Linear models with five biometric characters viz., height of the cane, girth of the cane, width of the third leaf determined from the selected plants of each plot and number of canes/tillers and number of leaves determined on a whole plot basis were sufficient to predict the plot yield of the crop as early as in the fifth month of plant growth with an accuracy in the range 68 to 90 per cent. Path analysis revealed that height of the cane and girth of the cane were the t wo important characters contributing towards cane yield in all stages of plant growth. Using the forecasting models fitted with principal components as explanatory variables, yield could effectively be predicted with 81.4. per cent accuracy for variety CO-997 and with 76 per cent accuracy for variety 00-62175 in the Sixth month of plant growth.ThesisItem Open Access Balanced designs for biological experiments in blocks of natural sizes(Department of Statistics, College of Veterinary and Animal Sciences, Mannuthy, 1983) Malika, V; KAU; Surendran, P UAs a preliminary result we have established Fisher’s inequality associated with a BIB design and generalized it to balanced binary designs with unequal replications and unequal block sizes to balanced n-ary equireplicate designs and also to BIB designs in which one treatment alone is allowed to repeat more than once in a block. Further it is shown that a balanced proper binary design is equireplicate. From existing BIB designs we have constructed balanced binary and ternary designs. A novel method of construction is as follows: Let there be a BIB design with parameters v, b, r, k, λ. From each block form k blocks each of size k+1 with block content as all treatments of the block with one distinct treatment repeated in a block. The resulting design will be a balanced ternary design with parameters v1=v, b1=kb, r1=r(k+1), λ1= λ(k+2). Kroneckor product is applied for the construction of balanced ternary designs by collapsing blocks of a BIB design. We have proved using Kroneckor product, that existence of a resolvable BIB design implies the existence of a proper balanced ternary design and this is an improvement over the results due to Dey (1970). Further it is shown that method of Kroneckor product used for the construction of balanced ternary designs can also be used for the construction of partially balanced ternary designs. Methods have been devised for the construction of balanced ternary designs making use of Finite geometrices and Galois field.
