Optimization of immature embryo tissue culture in Iranian bread wheat cultivars

Improvement of wheat(Triticum aestivum) by biotechnological approaches is currently limited by a lack of efficient and reliable tissue culture methodology. In this report, immature embryos of seven Iranian bread wheat cultivars were used to evaluate their ability of callus induction, green spot formation, shooting and regeneration frequency. Seven wheat cultivars were evaluated using four embryogenic callus induction medium and three regeneration medium in a split-split plot based on completely randomized design with four replications. Analysis of variance showed a significant difference between cultivars for all the in vitro traits studied except percentage of callus induction after 30 days from culture. Significant difference was found among callus induction media for all the studied traits. The cultivar X callus induction medium interaction was significant for percentage of callus induction, volume of callus, percentage of green spot, number of green spot per callus, percentage of shoot formation, and regeneration frequency. The effects of regeneration media and its interaction with cultivar and callus induction medium were significant for percentage of green spot, number of green spot per callus, percentage of shoot formation and regeneration frequency. The results showed that Atilla-50Y followed by Alvand were the best cultivars for callus and embryogenic callus induction. Mean comparison of callus induction mediums, showed that medium B2 was not suitable for callus induction but this medium performed well for embryogenic callus induction. The medium containing MS (Macro + Micro) + Thiamine-HCl + L-Asparigine +2,4-D + Maltose + Agar was best for callus induction as well as embryogenic callus production. Regeneration medium containing MS (Macro + Micro + Vitamins) + myoinositol + IAA + BAP + Sucrose + Agar acted better than the others. Interaction of B*C expressed that combination of B2C1, B2C3 and B3C3 medium were the best for callus induction, green spot and shooting in Atilla50Y, Atrak and Alvand/Tajan cv., respectively. In toto Atilla50Y and Alvand cultivars were better than others for callus formation and regeneration. The results suggest that by selecting only calluses producing early green spots, the experimental efficiency will be increased.