野生荆条种子休眠原因及两个采摘时期萌发条件的探究

Study on the Reasons of Dormancy of Wild Vitex negundo var. heterophylla Seeds and the Germination Conditions of Two Picking Periods

摘要: 本文以直接采摘的野生荆条种子为材料，探究了荆条种子休眠原因及两个采摘时期对荆条种子萌发率的影响。作者对2017年9月26日(绿叶期)和同年12月5日(枯叶期)直接采摘的荆条种子，分别进行了水引发处理(1 d, 2 d, 3 d)、赤霉素处理(0.5 mg/L, 1 mg/L, 2.5 mg/L, 5 mg/L, 10 mg/L)以及聚乙二醇处理(5%, 10%, 15%, 20%)，以提高种子萌发率。结果表明：两个时期采摘的荆条种子浸提液都对油菜种子的萌发有一定的抑制作用，间接说明荆条种子休眠原因之一是种子中有抑制物质的存在。12月份采摘的种子萌发率较9月底采摘的高，说明采摘时期对荆条种子萌发有一定影响，可能12月份收集的种子发育较9月底的良好；12月份采摘的种子经水引发2 d后，萌发率最高为(48.67% ± 5.03%)，比对照(16.00% ± 4%)显著提高(P < 0.01)；未处理种子萌发率低，暗示种子存在后熟作用。该研究结果表明采摘时期及处理方法对野生荆条种子休眠的破除，萌发率的提高起着重要作用。

Abstract: In this paper, wild Vitex negundo var. heterophylla seeds collected directly were used as materials to explore the reasons of seed dormancy and effect of two picking periods on germination rate of Vitex negundo seeds. Vitex negundo seeds were respectively collected on September 26, 2017 (green leaf period) and December 5, 2017 (dead leaf period) with hydro-priming treatment (1 d, 2 d, 3 d), gibberellins treatment (0.5 mg/L, 1 mg/L, 2.5 mg/L, 5 mg/L, 10 mg/L) and polyethylene glycol treatment (5%, 10%, 15%, 20%) to improve germination rate. The results showed that the leaching solution of seeds collected in two periods had a certain inhibitory effect on the germination of rapeseeds, which indirectly indicates one of the reasons for seed dormancy is the inhibitory substances in the seeds. The germination rate of seeds collected in December was higher than that collected at the end of September, which shows that the collection period had a certain effect on the germination of Vitex negundo seeds, and the development of seeds collected in December were better than that in September. Seeds collected in December showed the highest germination rate (48.67% ± 5.03%) after hydro-priming for 2 days, the germination rate, which was significantly higher than that of the control group (16.00% ± 4%) (P < 0.01). The germination rate of untreated seeds was low, indicating that the seeds had post-ripening effect. The results showed that the picking period and treatment method played important role in breaking dormancy and increasing germination rate of wild Vitex negundo seeds.