木麻黄种子老化特征及其影响因素

Study on Aging Characteristics and Influencing Factors of Casuarina equisetifolia Seeds

种子雨老化将影响种子的萌发,从而影响植被天然更新及恢复。采用自然老化和人工老化相结合的方法,探究木麻黄种子老化的特征及其影响因素。木麻黄种子置于海口木麻黄海防林不同微生境中进行自然老化,共设置12个处理;人工老化在实验室进行,共设置6个处理。结果表明,1)实验室自然存放条件下,木麻黄种子在27周内无老化迹象,种子发芽率的变化范围为42.0%~72.0%;2)悬挂在树干上的种子发芽率显著高于实验室对照组发芽率(p<0.05),但老化不明显;置于林下的种子在2周内出现快速老化,老化的顺序依次为:凋落物上>凋落物中>腐殖质中;3)水分反复胁迫显著加速了种子老化(p<0.05)。综上所述,木麻黄原生境高温,晴天-雨天交替变化导致水分生态因子的震荡波动是加速木麻黄种子老化的影响因素之一。

Rapid seed aging will affect seed germination, and thus affect the natural regeneration and restoration of vegetation.The characteristics and influencing factors of Casuarina equisetifolia seed aging were studied by combining natural aging with artificial aging.C. equisetifolia seeds were placed in different microhabitats in Haikou Casuarina marine forest for natural aging, and twelve treatments were set up.And, the artificial aging was carried out in the laboratory, and 6 treatments were set up.The results showed as follows 1) C. equisetifolia seeds showed no signs of aging within 27 weeks of natural storage in laboratory, and the germination rate of seeds varied from 42.0% to 72.0%. 2) The germination rate of the seeds hanging on the trunk was significantly higher than that of the laboratory control group(p<0.05),but the aging was not obvious.The seeds placed in the forest showed rapid aging within 2 weeks, and the order of seed aging was on litter > in litter > in humus. 3) Repeated water stress significantly accelerated seed aging(p<0.05). In conclusion, the high temperature the oscillation of water ecological factors caused by high temperature and sunny-rainy days in original habitat of C. equisetifolia was one of the influencing factors to accelerate seed aging of C. equisetifolia.