Germination at stress temperatures and ABA content of pepper (Capsicum annuum L.) seeds in relation to seed development

Changes in the percentage and time of germination at various temperatures (15, 25, 35 degrees C) and ABA (abscisic acid) content of pepper seeds harvested at 50, 60, 70 and 80 DAA (days after anthesis) were studied during growing seasons in 2001 and 2002. Seed dry mass ranged from 4.9 to 5.2 mg per seed in 2001, and from 4.7 to 5.0 mg per seed in 2002. However, seeds harvested at 70 DAA not only had maximum germination percentages, but also showed the lowest mean germination time for all three temperatures in both years. Delayed harvest (80 DAA) decreased germination percentages as a result of stress, and promoted viviparous germination in the mother plant. ABA content of the seeds increased gradually up to maturity with values of 226 ng g(-1) fresh weight (ng g(-1) FW) at 70 DAA in 2001, and 203 ng g(-1) FW at 60 DAA in 2002. It declined to a level between 85 and 90 ng g(-1) FW in the final harvest of the both years. Germination at stressful temperatures and ABA contents of the pepper seeds with respect to seed development are discussed.