The role of hydrogen peroxide in wheat male sterility induced by SQ-1

The objective of this study is to elucidate the role of H2O2 in wheat male sterility induced by SQ-1, a new kind of chemical hybridizing agent. We investigated the effects of SQ-1 + DMTU and SQ-1 on the content of H2O2, the transcript levels and activities of SOD, POD, CAT, and APX, and the relative male sterility rate and seed setting rate, and starch-KI staining of pollen grain. The results showed that SQ-1 increased production of H2O2, the activity of APX and the transcript levels of POD and APX, and decreased the activities of SOD, POD, and CAT and the transcript levels of SOD and CAT, compared with control. SQ-1 + DMTU could decrease the production of H2O2 and the transcript levels of POD and APX and increase the activities of SOD, POD, and CAT, compared with SQ-1 alone. However, DMTU could only partly reversed the relative male sterility rate and seed setting rate induced by SQ-1. SQ-1 decreased the number of pollen grains dyed black, compared with control. Treatment with SQ-1 + DMTU increased the number of pollen grains dyed black, compared with SQ-1 alone. Our results indicated that the overproduction of H2O2 was one of reasons for the male sterility induced by SQ-1.