Cross-talk between cold and bispyribac-sodium on rice seedlings

Abstract

The shifting of rice planting date to early spring improved weed control, which is important to achieve high yield. However, early planting date exposes rice seedlings to cold stress, slowing crop establishment and affecting herbicide selectivity. The objective of this study was determine the effects of cold stress and bispyribac-sodium application on rice seedlings’ gene expression and physiological patterns. The experiment was performed in greenhouse in a factorial arrangement, and treatments included: factor A – two planting dates: late September and early November; factor B consisted in bispyribac-sodium application at rate of 50 g ai ha−1 and untreated check. Bispiribac-sodium caused greatest injury to rice seedlings at the early planting date. Lipid peroxidation and total phenol accumulation was stimulated by low temperature but, was not affected by bispyribac-sodium application. Gene expression of OsSOD, OsCAT, OsAPX, OsDREB1A, OsCDPK13, OsCYP72A2, OsGSTL2 and OsGSTU10 were responsive to low temperature and presented upregulation when exposed to the herbicide, providing evidence of an interaction between temperature and herbicide applications. Cold stress likely affects herbicide metabolism and effect rice seedling e oxidation mechanism response to herbicide.