Abstract:In this research,the biological characteristic stability,the characteristics of morphology,photosynthesis and growth of 8 different ecotypes belong to Apocynum and Poacynum (common name:Luobuma) in Altay of Xinjiang were analyzed,aimed to afford scientific base for the protection and utilization of Luobuma germplasm resources.The results showed that:(1) morphological characteristics of each ecotype of Luobuma were stable except BMK ecotype.(2) Net photosynthetic rates (Pn) of 8 ecotypes of Luobuma were 17.8-30.1 μmol·m-2·s-1 and 9-16 μmol·m-2·s-1 at forenoon and noon,respectively.Pn was reduced by 6%-45% at noon compared with forenoon of which BMB ecotype and BMZ ecotype given the lowest and the highest Pn value among the 8 ecotypes of Luobuma.(3) Variation characteristics of Pn,transpiration rate (Tr) and Ci/Ca values were consistency for most ecotypes,which showed that the “midday depression” was affected by stomatal conductance (Gs).but the “midday depression” of BMF ecotype was affected by non-stomatal factors.(4) DBM ecotype belongs to “high photosynthetic rate,low transpiration rate,high WUE”,LHM ecotype belongs to “low photosynthetic rate,low transpiration rate,high WUE”.BMB belongs to “high photosynthetic rate,high transpiration rate,low WUE” and “low photosynthetic rate,low transpiration rate,low WUE” at forenoon and noon,respectively.BMZ ecotype was counter to BMB ecotype.(5) The plant height (>110 cm),ground diameter (>8.2 mm) and leaf dry weight (>22.6 g) of BMF and BMB ecotypes were the highest than that of other ecotypes.The internodes length of DBM ecotype was the longest (>6.5 cm).The results indicated that most Luobuma ecotypes had formed stable characters for adapting to the environment in the long-term evolution.BMB ecotype had tolerance of strong highlights and high temperature and utilization of weak light.LHM and BMB ecotypes could be used to product leaves.BMF and BMH ecotypes could be used for leaf and fiber product,while DBM ecotype was not suitable to plant in Altay.