Phenotypic stability of mutant sugarcane (Saccharum officinarum L.) tolerant to drought stress based on variations in morphological traits at the greenhouse scale

One of the problems of sugarcane (Saccharum officinarum L.) cultivation due to unpredictable weather is stunted growth, which leads to decrease productivity. Efforts to enhance sugarcane productivity under drought stress can be achieved through plant breeding via mutation induction. Changes in phenotypic stability in mutants lead to morphological alterations that subsequently increase adaptability to water deficit stress. Previous research has resulted in 11 superior mutant sugarcane clones produced through colchicine induction from 4 drought-tolerant sugarcane varieties, namely GMP6, RGM047, RGM1183, and RGM186, at PT Gunung Madu Plantations (GMP). The identification and evaluation of the stability of five morphological traits of leaves and leaf sheaths need to be conducted on these 11 superior drought-resistant sugarcane clones in a greenhouse setting. All clones exhibited diversity in the morphological traits of leaf color and the ease of leaf sheath detachment, with a significance level of 0.05. A dendrogram from the phylogenetic relationship analysis formed three main clusters based on similarity in correlation coefficients, similarity index, taxonomic distance, and cluster analysis. Meanwhile, Principal Component Analysis of the five morphological traits formed two clusters, showing the total variation on two axes, with axis 1 accounting for 90.21% (eigenvalue 5.84) and axis 2 for 4.42% (eigenvalue 0.28), totaling 94.64% for both axes. The clustering was based on traits that strongly contributed to the grouping, namely leaf width, leaf blade curvature, leaf color, leaf sheath traits, and leaf sheath color.