Application of mannitol as pre-treatment and sucrose supports callus induction through anther culture in Gossypium arboreum

Diploid or tree cotton (Gossypium arboreum) species may provide a breeding source for fiber quality and disease resistance. Developing homozygous lines of Gossypium arboreum through anther culture can be a successful strategy for breeding the parental lines needed for cotton hybrids. This study describes callus induction on four G. arboreum genoytypes under various concentrations of sucrose as well as plant growth regulators. Explant materials were derived from immature anther and grew on modified Murashige and Skoog (MS) media. Prior to main treatment, mannitol application were applied to anthers with concentration of 0.7 M and modified MS media consisted of 3%, 5%, and 7% sucrose, as well as an addition of IAA, NAA, BAP, 2,4-D and Kin. Optimum callus formation was observed in Marvi genotype, in a medium containg IAA as well as sucrose between 5-7%. Furthermore, combination of IAA and NAA with sucrose 7% indicates highest number of embryogenic calli. However, Marvi genotype showed decreased rate of callus formation when the amount of sucrose increased on MS supplemented with NAA medium. The results indicated that the best formula on each genotypes were different. However, MS media with IAA (1 mg/l) + kin (0.2 mg/l) + CM (70 ml/l) + sucrose 5% provided the best performance to produce embryogenic calli on each genotypes. Our report can be utilized as an opportunity and strategy to obtain double haploid lines as a parental source in hybrid production.