| Caraganas (Caragana korshinskii, Caragana microphylla and Caragana intermedia) are the most importmant shrub plants used for ecological conservation in North-western region of China. Caragana seed industry played an important role in the local economy in Caragana producing areas. Seed pests have caused heavy losses to Caragana seed industry. In order to bring the Caragana seed pests under control and to promote seed industry, a study on pest characteristics and infections on Caragana seeds were conducted. The main results found in the study include: Caragana seed pests of Bruchophagus neocaraganae, Kytorhinus immixtus and Etiella zinchenella are widely distributed in Inner Mongolia Autonomous Region, causing seed quality deteriorated. Pest infestation degrees in all areas invested are above ++. Average infection rate was 26.53%. Seed weight loss due to pest infections was 3.12g per 1000 seeds. Seed germination rate was lowered by 9.51%. Life history and biological characteristics of the three pests, which were found different with the ones on the grain crops in the southen China, were described. Spatial distribution model were studied using Tayler Index and Iwao Regression methods. Optimum sampling method for investigating infestations was formulated. Combined with the observations on the flowering and seed development of the three caraganas, popolution dynamics of the three pests were studied and integrated control indexes were calculated. The chemical pesticide lambda-cyhalothrin 87.50ml/ 666.7m2 and lambda-cyhalothrin 50.83ml/ 666.7m2 were used for chemical control of the pests and the control rates reached 88.91% and 85.06%, respectively. Control rates of two kinds of biochemical pesticides abamectin 50.83ml/666.7m2 were 81.76% and 81.42%, respectively.
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