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The Xishuangbanna tropical rainforest in Yunnan Province is the greatest biodiversity hotspot in China. However, the biodiversity of this region is under threat, making seed conservation through seed and/or germplasm banking particularly urgent and crucial. Seed desiccation sensitivity limits the possibility of seed banking of 47% of tropical rainforest species. Thus, knowing if a species has desiccation-sensitive seeds is an important first step in seed banking; however, often resources are limited, making it difficult to determine storage behaviour for all the species in a region. Prediction of seed sensitivity using the SCR-SM model based on seed-coat ratio (SCR) and seed dry mass (SM) might be an alternative for determining desiccation sensitivity of seeds of each species. Here, seed-desiccation sensitivity of 101 woody species from the Xishuangbanna tropical forest were analysed using this model, and physiological determinations were made for a total of 25 species. Seed storage behaviour for 59 species was used for model validation, and storage behaviour of 88% of these species was successfully predicted. Seed storage behaviour of 83% of the 59 species was successfully predicted using the 1000-seed weigth-moisture content (TSW-MC) criteria, which include seeds with 1000-seed weight >500 g and seed moisture content at shedding of 30 -70%. The two predictive methods were subsequently used to predict seed desiccation sensitivity for another 42 species from Xishuangbanna whose storage behaviour was uncertain. Our results indicated that~50% of the species in Xishuangbanna are likely to have desiccation-sensitive seeds.Journal compilation Ó CSIRO 2014 www.publish.csiro.au/journals/ajb PðD À SÞ ¼ e 3:269À9:974aþ2:156b 1 þ e 3:269À9:974aþ2:156b ;where a is SCR and b is log 10 (seed mass) in g. For estimation of P(D-S), seed mass should range between 0.01 mg and 24 g, and SCR between 0 and 1. When P(D-S) > 0.5, seeds are likely to be desiccation-sensitive, and when P(D-S) < 0.5 seeds are likely to be desiccation-tolerant. The TSW-MC criteria for identificationAccording to the TSW-MC criteria (Chin et al. 1984;Hong and Ellis 1996), seeds with a TSW of >500 g and MC of >30% are desiccation-sensitive. In our study, seed storage behaviour of 306 Australian Journal of Botany Q. Lan et al.