温、湿度条件及不同种子处理对棉籽吸胀冷害的影响

Effect of Moisture、Temperature and Seed Pretreatments on Imbibitional Chilling Injury to Cottonseeds

棉籽在4－5℃条件下吸水，发生吸胀冷害的程度随吸水速度的加快而减轻，随吸水时间的延长而加重；在10-12℃、18－20℃的水中吸水分别超过16小时、12小时，会因吸水时间过长使部分棉籽的种子活力降低，而使正常发芽率降低。经温汤浸种和预冷处理的棉籽能耐72小时0－5℃的低温，且耐较长时间低温的能力强于干籽与晾干籽；干籽、晾干籽能耐24小时0－2℃的低温，且干籽耐短时间低温的能力强于湿籽。

The imbibitional chilling injury to cottonseeds varies under different moisture and temperature conditions. During absorbing water at 4~5℃,the more rapidly cottonseeds absorb water,the less they are injuried by the imbibitional chilling ；with the elongation of the water absorptiontime, cottonseeds are injuried more heavily. The cottonseeds soaked in the water at 10 ~ 12℃and 18~20℃ for more than 16hr. and 12 hr. repectively show a lower germination percentagebecause of a longer time of absorbing water to reduce the activity of some cottonseeds.Umder different pretreatment conditions,the seeds display the various abilities to toleratethe low temperature of 0~5℃. The seeds soaked in hot - water at 30℃ 。air-dried and stored at0~ -2℃ for 10 days can tolerate the 0~5℃ temperature for 72 hours and also are more tolerant to the low temperature of a longer time than the air-dried seeds and those fu1ly soaked andredried in the air. However,air-dried and redried seeds can maintain their vigor at 0~2℃ for24 hours. Morever, the capability of air-dried seeds to tolerate the 1ow temperature of a shortertime is stronger than that of the soaked seeds.