基质含水量对油茶容器苗的成活率、生长和电生理的影响

Effect of Substrate Water Content on Survival Rate,Growth and Electrophysiological of Camellia oleifera Seedlings

以1年生油茶容器苗为试验材料，采用称重法控制基质含水量，设置CK ，T1，T2，T3，T4和T5六个水分处理组，研究基质含水量对苗木成活率和生长生理的影响。结果表明：当基质含水量低于81％时，苗木成活率开始下降，且随着干旱胁迫时间的延长，成活率也随之下降。基质含水量为90％～81％时，新梢和新叶生长量、叶片大小为最大，其新梢长达到5．21cm ，新叶数为4．89，叶片长×宽为4．23cm ×2．43cm ；相反；此时的生物量最大（鲜重为7．92g ，干重为3．44g ）、根冠比最小（鲜重比为0．40，干重比为0．47）。由逐步回归分析结果得知，叶片电阻主要是由叶片含水量决定的，基质含水量为100％～91％时，各部分电阻为最小（其中新叶＞老叶＞基质），其叶片含水量最大（68．5％）。

To study the effect of substrate water content on seedlings survival rate and growth physiology ,one-year-old seedlings of Camelliaoleifera （Fengyang No .1） were chosen as experimental materials ,which were grown in six substrates of different water content by weigh-ting method （CK ,T1 ,T2 ,T3 ,T4 and T5） .The results showed that ：When the substrate water content less than 81% ,the survival rate of seedlings began to decline ,and with the increase of drought stress time ,the survival rate was also decreased .When substrate water content was 90%-81% ,the growth of shoots and new leaves ,leaf size were the largest and the value were 5 . 21cm ,4 .89 ,4 .23cm × 2 .43cm respectively .By contrast ,the biomass were largest （fresh weight was 7 .92g and dry weight was 3 .44g） ,and the ratio of root/shoot was the smallest （fresh ratio was 0 .4 and dry ratio was 0 .47） .We could knew that substrate resistance is mainly determined by the leaf water content was 100%-91% .from the stepwise regression analysis result .The re-sistance of the various parts were minimum （new leaves〉 old leaves〉 substrate） and the water content of leaf was the largest （68 .5% ） .