Geographic variation in traits of fruit stones and seeds of Melia azedarach.

In order to more accurately know the geographical variation characteristics of Melia azedarach, 18 traits of fruit stones and seeds from 70 provenances (17 provinces of China) were analyzed. The results showed that phenotype traits of fruit stones and seeds were significantly different among the provenances. The repeatability of most of the traits exceeded 85%, where the repeatability of 100-seed weight and fruit stone width was more than 98%, followed by 100-fruit-stone weight and seed sizes, and the repeatability of ridge-grain ratio and coefficient b of fruit stone was lower, only 74.56% and 49.14%, respectively. The provenance variation in some traits showed obviously geographical trends. From the east to west distribution, fruit stone width and weight, seed width, thickness of fruit stone coat and ridge of each fruit stone increased. Meanwhile, from the south to north distribution, fruit stone length, seed width, seed weight, ridge of each fruit stone and fruit stone coat ratio increased as well, and the seed shape was to be short oval. From low to high altitude, the width of fruit stone and seed, fruit stone weight, thickness of fruit stone coat, fruit stone ridge increased, fruit stone longitudinally tended to be round shape and seed to be stubby and oval. Using the cluster analysis of 18 traits of M. azedarach, 70 provenances can be divided into 8 types. The geographical pattern and characteristics showed significant different among provenance groups.