Implications of In Vitro Mutagenesis in Banana (Musa spp.)

Abstract

Banana is an important crop of Pakistan, grown on large scale in Sindh province of the country. This study was conducted to introduce genetic variability in banana variety basrai and to optimize the micropropagation protocol for the same genotype. Murashige and Skoog (MS) media supplemented with various concentrations of indole-3-acetic acid (IAA), N6- benzyl aminopurine (BAP), indole-3-butyric-acid (IBA) and naphthalene acetic acid (NAA) were used. The genotypes were also radiated via. three different doses of gamma radiation i.e. 10, 20 and 30 Gy. Excellent shoot growth and elongation parameters viz. number of shoots developed bottle-1 (25.77) and shoot length (17.44 cm) were recorded in plantlets cultured on MS media supplemented with 4.00 mg l-1 IAA + 6.00 mg l-1 IBA + 4.00 mg l-1 NAA and 40 g l-1 sucrose; and radiated using 20 Gy dose of gamma radiation. The same combination of culture media and gamma rays’ treatment also showed least days to shoot initiation. Minimum observations for the growth parameters were observed in plantlets radiated with 30 Gy of gamma radiation and grown in MS media containing 2.00 mg l-1 IAA + 2.00 mg l-1 BAP + 2.00 mg l-1 NAA and 40 g l-1 sucrose. Regarding treatments of gamma radiation used in the study, lower doses like 10 and 20 Gy showed stimulatory effects on plantlets’ growth and development while 30 Gy was lethal. This study is significant for banana breeding as apposite induction of genetic variation through mutagenesis and optimal maintenance in the tissue culture will help in developing elite genotypes having near-commercial attributes.