Stepwise regression, correlation and path-coefficient analysis for sugar and cane yields in new sugarcane somaclones

Abstract

The obtained results could be displayed the effeteness of stepwise regression analysis to determine the strongest trait/s to produce the high sugar, cane yields and sugar recovery in sugarcane. The model which has two independent traits of cane yield (CY) and sugar recovery (SR) resembled to be the fit model for sugar yield and gave R 2 = 1.000 in second and third ratoon crops as well as over both of them. Also, the model which has two independent traits of sugar yield (SY) and sugar recovery (SR) resembled to be the fit model for cane yield and gave R 2 = 1.000 in second and third ratoon crops as well as over both of them. The model included three traits of sucrose (SUC), brix (BR) and pol (PO) with R 2 =1.000 in second ratoon or SUC and BR with R 2 = 0.999 in third and over both ratoons crops, resembled to be the fit model for sugar recovery. High positive and significant estimates of correlation coefficients were recorded between cane yield and each of stalk height, stalk weight, stalk number/fed and sugar yield in all studied ratoon crops. High and positive significant estimates of correlation coefficients were recorded between sugar yield and each of stalk height, stalk weight and stalks number/fed over the two ratoon crops. It is remark result that the traits of brix, purity %, pol and sugar recovery were correlated each other in high significant and positive estimates in both ratoon crops, revealing the high quality traits as important components express high sugar in sugarcane. Pathcoefficient analysis through the second, third and over both of ratoon crops revealed that the stalk weight, stalk number/fed and cane yield had the greatest direct and indirect influences on sugar yield. Moreover, the stalk number and stalk weight had the greatest direct and indirect influences on cane yield. The path coefficient analysis exhibited that sucrose contributed the greatest effects on sugar recovery even direct or indirect effects via pol, brix and purity over the both ratoon crops.