Using rice anther culture for the production of doubled haploid lines with increased induction frequencies

Developing doubled haploid (DH) lines through anther or microspore culture is an important strategy for shortening breeding cycles and accelerating crop improvement. The present study aimed to enhance the regeneration of rice haploids through anther culture-induced calli and subsequently convert them into DH bacterial leaf blight (BLB)-resistant lines. Eleven lines expressing resistance against prevalent strains of Xanthomonas oryzae pv. oryzae were crossed as male parents with elite high-yielding basmati and non-Basmati varieties to develop F(1)s for collecting anthers at the appropriate stage of pollen development. Optimum callus induction in 36.45% of the genotypes was obtained on N-6 medium supplemented with maltose (40 g/l), 2,4-D (2.5 mg/l), and kinetin (0.5 mg/l), and further callus proliferation was enhanced in the presence of amino acids, particularly a combination of cysteine and tryptophan. High scores of haploid regeneration frequency were obtained in MS medium augmented with sucrose (30 g/L), BAP (2.0 mg/l), kinetin (0.5 mg/l), and NAA (0.5 mg/l). Fortification of regeneration medium with tryptophan (25 mg/l) and cysteine (40 mg/l) resulted in maximum regeneration of calli. Ranbir Basmati, Saanwal Basmati, Basmati 564, Ranbir Basmati & times; IRBB53, Ranbir Basmati & times; IRBB60, Basmati 564 & times; IRBB57, and Basmati 370 & times; IRBB56 were observed to be the most responsive genotypes for haploid regeneration. An average of 76.34% DH induction frequencies were obtained in colchicine (0.1%) treatment, while 41.56% were spontaneously induced DHs. Consequently, using anther culture to develop DH lines is a promising approach for genomic resources and elite varieties in a shorter breeding period.