Embryoid and callus formation from microspores by anther culture from july to november in pepper (Capsicum annuum L.)

Embryoid and callus were regenerated from microspores of six cultivars of pepper (Capsisum annuum L.) by culture of anthers obtained from July to November. Anthers containing microspores at the uninucleate stage were planted in MS media supplemented with 0.004 mg ・liter-1 2,4-D, 0.1 mg ･liter-1 kinetin, 30 g ･ liter-1 sucrose and 2 g ･ liter-1 Gelrite, kept at 35℃　for 24h, and then incubated at 25℃ under 16h daylength for 40 days. Frequency of embryoid and callus formation varied with cultivars and period of initiation. Embryoid formation was more effective from September to October. A temperature of between 15 to 25℃　in the months of September and October was effective for higher embryoid formation. Even though embryoid and callus formation was obtained in all cultivars, the frequency of embryoid formation was higher in Cheongyang and Fushimi Amanaga, while callus formation was higher in Shishtou and California Wonder. Embryoid transferred to MS medium developed to plantlets, and were acclimatized. The number of chromosomes in the root tip cells was 12 (haploid) in 19 plants, 24 (diploid) in one plant and 20 to 23 (aneuploid) in 3 plants.