In-vitro selection of sugarcane (Saccharum officinarum L.) putative mutant for drought stress

Abstract

In-vitro selection through tissue culture followed by field testing is one of the breeding methods to improve sugarcane varieties with drought-tolerant. This research aimed to obtain putative mutant sugarcane physically mutated using gamma-ray irradiation that passed the in vitro drought selection using PEG-selecting agents. This study was conducted from March to December 2016 using embryogenic calli of PSJT 941, PS 862, and BL varieties. The experimental design was the factorial randomized complete design with two factors, i.e. irradiation dose (0, 5, 10, 15, 20, 25, 30, 35 Gray) and PEG concentration (0, 10, 20%). The irradiated calli selected by PEG media had changed in color from yellowish-white to brownish and blackish and indicated the growth inhibition. The higher the dosage of irradiation and the concentration of PEG, the more calli with growth inhibition. Some putative callus mutants successfully passed in vitro selection using 10 and 20 % PEG, which showed tolerance to drought stress. The appropriate irradiation dose to produce tolerant mutants is 5 - 30 Grays for PS 862 and BL varieties, and 5-25 Grays for PSJT 941. To recognize the mutant response further, it is necessary for in-vivo selection at the greenhouse and in the field.