Effects of leaf anatomical structure features on cold resistance of oil palm（Elaeis guineensis Jacq.） introduced in different regions in Guangdong Province

In order to further evaluate effects of leaf anatomical features on cold resistance of oil palm (Elaeis guineensis Jacq.) earlier introduced in six regions (populations) in Guangdong Province, i.e. Shenzhen, Dongguan, Maoming, Huazhou, Zhangjiang and Leizhou. Thirty eight individual palms were used for observation of leaf anatomical features and semi-lethal temperature (LT50) and the relationship between leaf anatomical feathers and LT50 and the main factors affecting the cold resistance of oil palm in individual palms and populations were compared and analyzed with the methods of variation, phenotypic correlation and path coefficient. The results showed that there was significant difference in leaf anatomical structure and LT50 in individual palms and populations, but not significant in the length of vascular bundle and cell tense ratio in oil palm populations. The width of vascular bundle in individuals and the thickness of adaxial cuticle, the thickness of abaxial hypodermis, the thickness of abaxial epidermis, the length and the width of vascular bundle in populations were not significantly correlated with other features, and that all of features had no significant correlation with LT50 whether in individuals or in populations. The spongy mesophyII thickness in individuals was the determinant of LT50 with the highest negative direct effect, but the thickness of adaxial cuticle was most important factor with the highest positive direct effect on LT50.