Effect of three insecticides and two herbicides on rice (Oryza sativa) seedling germination and growth.

Rice (Oryza sativa L.) is one of the most important food crops worldwide. However, it is also a valuable tool in assessing toxicity of organic and inorganic compounds. For more than 20 years, it has been an approved species for standardized phytotoxicity experiments. The objective of this study is to determine germination and radicle (root) and coleoptile (shoot) growth of rice seeds exposed to three insecticides and two herbicides, commonly used in the agricultural production landscape. Although no germination effects of pesticide exposure were observed, significant growth effects were noted between pesticide treatments. Coleoptile growth was significantly (p ≤ 0.05) lowered in metolachlor/atrazine mixture, diazinon, and lambda-cyhalothrin exposures when compared with controls. Radicles of fipronil-exposed seeds were significantly larger (p ≤ 0.05) when compared with controls. This research contributes to the phytotoxicity assessment database, in addition to laying the foundation for the use of rice as a phytoremediation tool for agricultural pesticide runoff.