适宜槟榔幼苗根系生长的土壤水含量筛选

【目的】筛选适宜槟榔幼苗根系生长的土壤水含量,为制定槟榔幼苗水分灌溉标准提供参考依据。【方法】以盆栽槟榔幼苗为试验材料,分别设土壤相对水含量(30±5)%(T1)、(45±5)%(T2)、(60±5)%(T3)、(75±5)%(T4)和(90±5)%(T5)处理,持续控制60 d,分别测定各处理幼苗的鲜重、干重、干物质分配情况及根系形态和活力。【结果】T5处理槟榔整株幼苗、根、茎及叶的鲜重和干重均最重,其中,整株幼苗鲜重极显著重于其他处理(P0.01,下同)。T4和T5处理槟榔整株幼苗的干重、根鲜重及根干重均显著重于T1、T2和T3处理(P0.05)。T1、T2和T3处理槟榔幼苗的干物质多数向茎和叶分配,其中T1处理槟榔幼苗叶片干物质占整株的百分比增加11.32%,茎的百分比增加5.00%,根的百分比下降8.63%。土壤水含量与幼苗根系活力呈正相关,相关系数为0.9545。T4和T5处理槟榔幼苗根系的总鲜重、总干重、总长度、总表面积及总体积均极显著高于T1、T2和T3处理。【结论】槟榔育苗的土壤相对水含量以(75±5)%为宜,此条件下最有利于槟榔幼苗根系生长。

Screening of soil water content suitable for Areca catechu seedling root growth

Objective]The present study was conducted to screen soil water content suitable for Areca catechu seedling root growth, in order to provide reference for drawing up irrigation standards for A. catechu seedlings. Method]Potted A. catechu seedlings were utilized in this study. Five soil water content treatments were set in the research, namely(30±5)%(T1), (45±5)%(T2), (60±5)% (T3), (75±5)% (T4) and (90±5)% (T5). After 60 days water control, fresh weight, dry weight, dry matter distribution, root activity and root morphology of A. catechu seedlings under each treatment were mea-sured. Result]Under T5 condition, fresh weight and dry weight of root,stem,leaf and whole seedling were at the highest level. In addition, fresh weight of whole seedling was significantly heavier than those under other treatments(P<0.01, the same below). Dry weight of whole seedling, root fresh weight and root dry weight of A. catechu seedlings under T4 and T5 were significantly heavier than those under T1, T2 and T3(P<0.05). Under T1, T2 and T3, dry matter mostly distribut-ed to leaf and stem. In T1, ration of leaf dry matter to whole seedling dry matter increased 11.32%, stem dry matter ration increased 5.00% while root dry matter ration decreased 8.63%. Soil water content was positively correlated with seedling root activity, with correlation coefficient being 0.9545. Total dry weight, total fresh weight, total length, total surface area and total volume of seedlings under T4 and T5 treatment were significantly higher than those under T1 , T2 and T3. Con-clusion](75±5)%is the most appropriate soil water content for A. catechu seedling growth. Such condition is most suitable for A. catechu seedling root growth.