Oat Anther Culture: Genotype Effects on Callus Initiation and the Production of a Haploid Plant 1

Calli were initiated from 2,627 of approximately 65,000 anthers of oats ( Avena sativa L.) placed on various culture media. One haploid (n = 3x = 21) and two diploid (2n = 6x = 42) plants were recovered from an anther of the cultivar ‘Stout’. These were the first plants known to be producebdy anther culture in oats. Ther elated cultivars Stout and ‘Clintford’ were the source of most of the anthers which formed callus. These lines responded with more than 30% anthers callusing under defined culture conditions, while no other genotypes among over 100 initially tested had more than 6% anthers callusing and most had none. When Clintford was crossed with five nonresponding genotypes, the F 1 plants from three of the crosses produced relatively high frequency anther‐callusing responses while F 1 plants of the other two crosses gave low responses indicating a complex inheritance of the trait. The highest frequency of callusing anthers was achieved with a Stout ✕ Clintford F 2 plant where 12 of 15 cultured anthers responded. Murashige and Skoog basal medium with 10% sucrose and no hormonegs ave the highest anther callus initiation frequencies among media tested, but the only anther to produce plants had been initially plated on a modified potato extract medium containing 2 mg/ liter 2,4‐dichlorophenoxy acetic acid and 0.5 mg/liter kinetin. This anther had also been heat‐shocked at 35 C for 24 hours immediately after plating and prior to standard incubation at 22 C. Cold shocks reduced sucrose levels, and the addition of various growth substances had either no or detrimental effects on callus initiation frequencies and did not promote plant differentiation. Means to regenerate plants from initiated calli on a consistent basis are needed to make oat anther culture a useful technique.