不同马尾松家系抗旱性评价

Drought resistance comparison of different Pinus massoniana family

以183个马尾松优良家系苗木为试验材料,结合干旱池反复干旱法和田间鉴定法筛选抗旱材料。结果表明:反复干旱胁迫下,50%苗木永久萎蔫时,各家系马尾松苗木萎蔫度分布区间为60.8%~100.0%,均值为(85.0±8.2)%;胁迫结束后,马尾松家系苗木存活率差异很大,在0.0%~100%之间,均值为(56.1±23.0)%;各马尾松家系萎蔫度与存活率极显著负相关,说明这两个指标评价结果一致。用于田间鉴定的20个马尾松家系中,耐旱性较好的10个家系树高生长量、保存率分别较耐旱性较差的10个家系高出18.3%、18.7%,均差异极显著;20个马尾松家系的苗木萎蔫度、存活率,造林保存率、树高生长量共4个评价指标均显著相关或极显著相关。以苗木存活率、造林保存率、林木树高生长量作为马尾松家系抗旱性评价指标,采用隶属函数法对初选的20个家系抗旱性进行综合评价。结果表明,苗木耐旱性强的马尾松家系较苗木耐旱性弱的家系抗旱,其抗旱性排名分别为P-8>P-43>P-39>P-41>P-26>N-62>P-16>T-3>P-18>P-30>T-15>T-4>T-17>N-64>N-67>N-22>Q-7>T-6>P-25>T-14,以P-8家系抗旱性表现最佳、T-14抗旱性表现最差。

Drought-resistant of 183 Pinus massoniana families were screened by the combination of repeated drought and field identification methods.The results showed that,when 50%seedlings were permanent wilting under repeated drought stress,the wilting degree distribution of the seedlings was 60.8%-100.0%and the mean value was(85.0±8.2)%.After the treatment,the survival rate of the seedlings was varied among 0%-100%with mean value of(56.1±23.0)%,and the witheriness index of the P.massoniana family was significantly negatively correlated with survival rate which indicating that the evaluation results of 2 indexes were consistent.Among the 20 species of P.massoniana families,the tree height of 10 families with better drought resistance was 18.3%and 18.7%higher than the 10 families with poor drought resistance.The results showed that there were significant correlations or highly significant correlations among the four evaluation indexes,including the survival rate,survival rate of afforestation and tree height growth rate of the 20 families.The drought resistance of 20 families was evaluated by the membership function method,and the results suggests that the drought resistance of the seedlings could be ranked by the followings:P-8>P-43>P-39>P-41>P-26>N-62>P-16>T-3>P-18>P-30>T-15>T-4>T-17>N-64>N-67>N-22>Q-7>T-6>P-25>T-14,P-8 perform best against drought resistance while T-14 perform weakest.