Application of factor analysis in sorghum [sorghum bicolor (L.) Moench]

The data of a varietal trial having 40 genotypes evaluated in three replications at Forage Research Project on forage sorghum [Sorghum bicolor (L.) Moench] were collected and were subjected to factor analysis using SAS software. The data on Days to flowering(DTF), Plant height(PH), No. of tillers /plant(NTP), Leaf stem ratio(LSR), No. of leaves/ plant(NLP), Leaf length(LL), Leaf width (LW), Stem girth ratio(SG), Green fodder yield(g) /plant (GFYPP), Dry matter content (DMC), and Dry matter yield(g) /plant (DMYPP) were used for the present study. The results revealed that the highest C.V.% (82.8 %) was observed for leaf stem ratio followed by dry matter yield and green fodder yield, number of leaves /plant and stem girth ratio. Almost at par results were observed for range coefficient. The genotypic correlation coefficients between green fodder yield of sorghum with leaf length, leaf width, stem girth and dry matter yield per plant were significant and positive at genetic level. Leaf length is significantly associated with leaf stem ratio, number of leaves per plant leaf width, stem girth and with dry fodder yield. The results of rotated factor analysis score values indicated that the first factor included green and dry fodder yield per plant and stem girth, leaf length and leaf width to be the important factor contributing 31.4 % of common variation in forage sorghum. Besides this the second factor consisted leaf stem ratio, number of leaves and tillers per plant which can contribute about 30.4 % of common variation, while third factor identified days to flowering over and above the two factors having 10.4 % common variation. The total common variation accounted by all three variables was 72.2 % . Green and dry fodder yield and leaf stem ratio exhibited more than 0.8 communality which indicates to have high common variation in sorghum . Thus, overall result suggested that selection of leaf length, leaf width and green and dry fodder yield are more important followed by leaf stem ratio, number of leaves and tillers/plant. Dry matter content and plant height needs to be controlled at the same time as the have negative loadings.