Silencing of the SlZF-31 gene decreases the salt stress tolerance and drought tolerance of tomato

The SlZF-31 gene is a member of the tomato C2H2 transcription factor family. Previous studies have shown that SlZF-31 gene expression is upregulated under drought stress and salt stress, but the specific function of this gene in tomato plants in response to these two kinds of stress is still unclear. To further explore the function of the SlZF-31 gene in tomato under drought stress and salt stress, we employed the virus-induced gene silencing method to reduce the expression of the SlZF-31 gene in tomato. The results showed that TRV2-SlZF-31 plants had higher levels of wilt and stem bending than CK and CK-TRV2 plants under drought and salt stress. The ABA content of TRV2-SlZF-31 plants were lower than those of CK and CK-TRV2 plants. The analysis of physiological indexes showed that the SOD and POD activity and the proline content of TRV2-SlZF-31 plants were lower than those of CK and CK-TRV2 plants, while the MDA content of TRV2-SLlZF-31 plants was higher than those of CK and CK-TRV2 plants. The accumulation of H2O2 and O2− in TRV2-SlZF-31 plants was greater than those in CK and CK-TRV2 plants. The values of the chlorophyll fluorescence parameters (ΦII and qL) of TRV2-SlZF-31 plants were significantly lower than those of CK and CK-TRV2 plants. These results showed that the silencing of the SlZF-31 gene reduces the drought resistance and salt tolerance of tomato. The finding of this study are expected to provide theoretical support for the study of abiotic stress in tomato.