Enhancement of low-temperature tolerance in watermelon (Citrullus lanatus) seedlings by cool-hardening germination

摘要: To determine and elucidate the role of cool-hardening germination in subsequent development low-temperature tolerance tropical subtropical plants, 10-day-old watermelon (Citrullus lanatus) seedlings two hybrids, Jingxin No.1 Longfengzaochen, germinated at 18 30°C, respectively, were removed from growth conditions 25°C exposed directly to –2°C for 24 h. The results showed that 18°C, improved seedling emergence rate developed –2°C. Low-temperature injury-associated changes electrolyte leakage lipid peroxidation cotyledons lower radicle vigour, measured as 2,3,5-triphenyltetrazolium chloride reduction, observed 30°C but not those presumably due accumulation soluble proteins. Radicle vigour a significantly negative correlation with cotyledon peroxidation. Seed less than optimal temperature may be feasible way improve cold plants.