Evaluation of dinotefuran utilization in rice cultivars from South China

Deep application of agrochemical in rice fields and coating pesticide on seedlings are efficient ways to achieve simple rice cultivation method. Insecticides applied by these means must be absorbed by rice seeds or roots and then distributed to various parts of the plant to exert their effects. Evaluating the efficiency of the absorption of pesticides by seeds among rice cultivars will be beneficial to the reduction and synergy of pesticides. After soaking and treating 51 rice seeds with dinotefuran at the concentration of 1 mmol/L, and the pesticide content in roots and leaves of rice were detected by UPLC. WinRHIZO software was used to analyze the morphological indexes of roots and evaluate the effect of dinotefuran on seed germination and growth. The results showed that different cultivars of rice had great differences in terms of their ability of dinotefuran absorption. The total accumulation of Guiyu 2, Hemeizhan, 93-11, Guihuazhan and Guiyu 7 in rice was relatively high. Overall, after exposing the seeds to dinotefuran, the diameter of the rice roots became smaller and the roots became thinner at the germination stage. But the number of root tips, root length, root surface area and root volume became larger comparing to the water control treatment. The conclusion was that Guihuazhan, Luxiang 658, Baguixiang and Juliangyou 750 were cultivars with high absorption of dinotefuran. And adverse effects on the growth of rice were not observed after they were exposed to dinotefuran in the rice seed stage. The results provided the information on improving pesticide utilization for rice cultivar in the stand point of the interaction between pesticides and crops.