Influence of Temperature and Host Plant on the Digestion of Frankliniella intonsa (Trybom) Revealed by Molecular Detection.

Frankliniella intonsa (Trybom) (Thysanoptera: Thripidae) is an important type of thrip and a polyphagous pest, which poses a serious threat to many crops, especially those in tropical regions of China. Its feeding behavior and the damage caused vary among different host plant species and are affected by ambient temperature and plant nutrients as well. The digestion rate is an important index for directly observing the digestion process, but there have been no studies directly measuring the digestion in thrips under the influence of different temperatures and host plants. Here, the digestion rate of F. intonsa was assessed by using a molecular diagnostic tool. We also determined the nutrient content in three host plant (mango, cowpea, and pepper), including soluble proteins, free fatty acids, soluble sugars, and water. The results showed that the high and low temperatures (16 °C and 32 °C) both seemed to accelerate the digestion of F. intonsa compared to the optimal temperature (26 °C) and the protein content of plants played an important role in the digestive response of F. intonsa to temperature changes. The findings can help reveal the feeding damage caused by F. intonsa to different plants and help to better understand its feeding ecology, according to its interaction with the host plant.