Abstract: 【Objective】A new practical and fine model to simulate dry matter accumulation and distribution in boll shell, seed cotton, fiber and seed at different cotton flowering stages was established.【Method】Cotton dry matter accumulation models were developed on the basis of relative thermal effectiveness (RTE), in consideration of the effects of the other main factors such as nitrogen nutrition , water stress and the ratio of supply and demand of assimilation product on the development of cotton bolls, with different genotypes, amount of applied fertilizer and different flowering stages.【Result】The value of the root mean square error (RMSE) between simulated and absorbed values for dry matter accumulation and distribution of a single boll, seed cotton and fiber of cotton bolls of pre-July 20, July 21 to Aug 15, Aug 16 to Aug 31 and post-Aug 31 was 0.1767-0.5659, 0.0725-0.5279, and 0.0613-0.2634 g, respectively. RMSE of a single collective model for dry matter accumulation and distribution was higher or vicinaler than that of the models simulated by stages.【Conclusion】This system of analysis methodology for cotton boll dry matter accumulation and distribution is precise and reliable.

Key words: Cotton boll, Different flower stages, Dry matter accumulation and distribution, Simulation model, Validation