Effect of salt stress on the ecological adaptability of Sogatella furcifera (Hemiptera: Delphacidae)

Soil salinisation poses a threat to the safe production of rice. Salt stress, as a key abiotic factor, directly affects rice and indirectly influences the population adaptability of important rice field pests. This study assessed the impact of salt stress on the ecological adaptability of Sogatella furcifera by measuring the nymphal developmental duration, survival rate, proportion of short-winged adults, proportion of female adults, number of eggs laid per female, female adult longevity, egg developmental duration, and egg hatching rate of individuals fed rice treated with different concentrations of NaCl (0, 25 mmol/L, 50 mmol/L, 75 mmol/L, and 100 mmol/L). The results showed that the nymphal developmental duration did not differ significantly from the control group under any of the salt stress treatments. The survival rate of nymphs decreased initially, then increased, and decreased again with increasing salt concentration. The survival rates of nymphs in the 25 mmol/L, 75 mmol/L, and 100 mmol/L treatment groups were significantly lower than those in the control group, while there was no significant difference between the 50 mmol/L treatment group and the control group. Salt stress significantly altered adult wing morph differentiation, resulting in a significant decrease in the proportion of short-winged individuals in the 75 mmol/L treatment group, but the proportion of female adults was unaffected. The number of eggs laid per female in the 25 mmol/L [(129.40 ± 23.06) eggs] and 100 mmol/L [(152.31 ± 14.37) eggs] treatment groups was significantly lower than that of the control group [(283.41 ± 32.30) eggs], whereas female adult longevity showed no significant changes. All salt stress treatments significantly prolonged the egg development duration, but no significant differences were observed in egg hatching rates. This study elucidates the regulatory effects of salt stress on key biological parameters of S. furcifera population, providing a scientific basis for precise monitoring and development of ecological control strategies against this pest in saline-alkali rice areas.