土壤水分含量对银杏生长及生物量分配的影响

应用温室盆栽试验方法,采用完全随机试验设计,研究了1 年生银杏(Ginkgo biloba L.)实生苗在不同土壤水分条件下的生长和生物量分配。试验共设16 个处理,即4 个银杏半同胞家系(44 号、11 号、55 号、32号)、4种水分水平(土壤含水量为土壤田间持水量的80%,60%,40%和20%),处理时间为100 d。研究结果表明:(1)银杏4家系相对高生长、相对地径生长、生物量增量、单株叶面积、单株根系体积等均随着土壤水分含量的减少而减少;(2)55号和44号家系随着土壤水分含量的减少,根冠比逐渐增大,而32 号和11 号家系在前3种水分条件下随着土壤水分含量的减少,根冠比逐渐增大,但在W4 水分条件下,根冠比均减少;(3)随着土壤水分含量的减少,银杏4家系根、茎和叶生物量增量均减少,但不同的家系减少程度不同,4 个银杏家系在不同土壤水分条件下,根、茎和叶生物量增量均表现为根的最多,茎的次之,叶的最少;(4)不同家系银杏生物量增量分配到根系的比例随土壤水分含量的减少而增大,而分配到茎和叶中的比例则随着土壤水分含量的减少而减少。

The Effects of Soil Water Stress on Growth and Biomass Allocation of Ginkgo biloba

One year old seedlings of ginkgo (Ginkgo biloba L.) were grown in a pot under greenhouse conditions with varying soil water levels to determine the growth and the biomass allocation.There were 4 different treatments of soil water and 4 ginkgo cultivars,and the time of treatment was 100 days.The results were as follows:(1) Relative height growth,relative caliper growth,biomass increment,plant leaf area and plant root volume of ginkgo decreased with decreasing of soil water content,but shoot/root ratio of varieties increased with decreasing of soil water content (except the treatment of W_4);(2)The biomass increments of root,stem and leaf of 4 varieties all decreased with decreasing of soil water content,and the order of biomass increments of root,stem and leaf of 4 cultivars was root>stem>leaf;(3)The allocation ratio of biomass increment of root increased with decreasing of soil water content,but the allocation ratio of biomass increment of stem and leaf decreased with decreasing of soil water content,and the allocation ratio of biomass increment of root was highest,and the second was stem,and the allocation ratio of biomass increment of leaf was lowest.