美洲黑杨无性系苗期生长与蒸腾特性研究

对12个美洲黑杨无性系苗期生长、蒸腾速率、水分利用效率及其影响因子的相关性进行研究,结果表明：各无性系的蒸腾速率日变化均呈单峰曲线规律,最大值出现在14：00左右.日平均蒸腾速率的大小次序为：tn01-n58＞ tn02-16＞ tn01-38＞ tn05-n53＞ tn04-n31＞xl-90＞ la06-n30＞ tn01-30＞ tn01-90＞ tn04-n52＞tn02-13＞ tn01-78;水分利用效率的大小次序为：tn01-90＞ la06-n30＞ tn02-13＞ tn04-n52＞ tn01-78＞ xl-90＞ tn01-n58＞ tn05-n53＞ tn02-16 ＞tn01-30＞ tn04-n31＞ to01-38.蒸腾速率与G5、VpdL、Tair和PAR呈正相关,与Ci和RH呈负相关;蒸腾速率与影响因子的相关程度依次为：PAR＞Gs＞ RH＞Tair＞Ci＞ VpdL;苗期的平均地径、苗高与Pn、Cond、RH、PAR呈正相关,与VpdL、Tair呈负相关.

Transpiration characteristics of Populus deltoides clone in seedling stage

By investigating on the seedling growth, transpiration rate, water use efficiency and its influencing factors, transpiration characteristics of 12 Populas deltoides clones were studied. Results showed that, the diurnal variation of transpiration rate of different clones had a single-peak curve, the maximum value appeared at about 14 ： OO. The sequencing of average transpiration rate was ： tnO1 -n58 〉 tnO2-16 〉 tnO1-38 〉 tnO5-n53 〉 tnO4-n31 〉 xl-9O 〉 laO6-n3O 〉 tnO1-3O 〉 tnO1-9O 〉 tnO4-n52 〉 tnO2 -13 〉 tnO1 -78. Tile sequencing of water use efficiency in mean was： tnO1 -9O 〉 laO6- n3O 〉 tnO2 -13 〉 ＇tnO4 -n52 〉 tnO1 - 78 〉 xl - 9O 〉 tnO1 - n58 〉 tnO5 - n53 〉 tnO2 - 16 〉 tnO1 - 3O 〉 tnO4 - 1131 〉 tnO1 - 38. The transpiration rate exhibited a positive correlation with Gs, VpdL, Tair and PAR, whereas negatively correlating with Ci and RH. The degree of correlation between transpiration rate and influence factors was： PAR 〉 Gs 〉 RH 〉 Tair 〉 Ci 〉 VpdL. The average ground diameter, seedhng height of seedling growth ＇exhibited negative correlation with VpdL, Tair, whereas positively correlating with Pn, Cond, RH, PAR.