Phenology, leaf and yield production patterns of sweet pepper under irrigated seasonal dry lowlands conditions, Papua New Guinea

Under seasonal irrigated dry-lowland conditions in Papua New Guinea (PNG), phenological parameters of three sweet pepper cultivars were quantified using thermal time after transplanting (°CdAT). First flowers appeared at 500-600 °CdAT, while green fruit maturity for harvest averaged 1200 CdAT. Increase in leaf numbers and crop height were initially slow before increasing linearly from 400-800 CdAT, after which leaf production and plant height rates declined at 800-900°CdAT. Reduction of leaf production and plant height was attributable to assimilate distribution in favour high fruit production over vegetative structures and flower production. Fresh weight of marketable fruits was similar across cultivars; nevertheless, New Ace produced 87% of marketable fruit yield (but lower total yield) than Giant Bell and Wonder Bell, which had 74% and 80%, respectively. This study is complemented by investigating internal competition for photosynthate in sweet pepper to improve crop management practices for enhanced fruit retention and yield quality.