Influence of Sowing Date on Seed Yield and Quality of Perilla (Perilla frutescens (L.) Britton var. frutescens cv. Dayu) in the Southern Paddy Field

Background: The growth and seed yield of the perilla cultivar ‘Dayu,’ sown on four different dates, were investigated to explore its potential as an alternative crop to rice and to determine the optimal sowing period for double cropping in paddy fields in the southern region. <br/>Methods and Results: Seeds were sown on four dates: May 24, June 9, June 22, and July 8, 2022. The period from sowing to flowering progressively shortened ans sowing was delayed. However, the time from flowering to seed maturity slightly decreased by 3 days between the sowing dates for the later sowing dates. The seed yield exceeded 110 ㎏/10a, with the number and length of inflorescences being greater in the early and late June sowings. Functional polyphenol content increased with later sowing dates and was higher in the late June and early July sowings. Additionally, growing degree days (GDD), total precipitation, and total sunshine during the growth period correalated positively with agricultural traits related to both vegetative and reproductive growth.<br/>Conclusions: Considering the seed yield, seed composition, lodging resistance, and crop connectivity in double cropping, mid-to-late June appears to be the most suitable time for sowing perilla seeds in paddy fields in the southern region.