Growth, maturity, germination and storage of litchi seeds

Abstract

Litchi seeds (cultivar ‘Shahi’) attained maximum dry weight 8 weeks after anthesis and then showed 42% germinability. Change of colour of testa from yellow-green to dark reddish-brown appeared to be a good visual measure of physiological maturity. At fruit maturity (i.e. at the end of the ninth week after anthesis), seeds contained 28.5% moisture (wet weight basis) and 100% germination was obtained. When kept for 1 week under ambient conditions (29–33°C), the moisture content fell below 19% and the seeds completely lost their germinability after 6 days. Rapid outdoor drying brought the moisture content down to 19.5% after 2 days. There was a strong positive correlation ( r=0.95) between seed moisture content and germinability, with 20% moisture being the critical level. Desiccation beyond this level killed the seeds. Prolonging viability by storing seeds in different moisture-retaining environments led to sprouting within 15 days. Seeds stored in sealed polythene bags showed 50.7% germination after 10 days. Seeds retained with fruits treated with benomyl (0.05%) and wax emulsion (6%) and sealed in polythene bags could maintain 42% viability for up to 24 days.