AUTHOR=Inayat Rehan , Khurshid Aroosa , Boamah Solomon , Zhang Shuwu , Xu Bingliang 

TITLE=Mortality, Enzymatic Antioxidant Activity and Gene Expression of Cabbage Aphid (Brevicoryne brassicae L.) in Response to Trichoderma longibrachiatum T6

JOURNAL=Frontiers in Physiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2022.901115

DOI=10.3389/fphys.2022.901115

ISSN=1664-042X

ABSTRACT=<p>Aphids are one of the most common insect pests in greenhouse and field crops worldwide, causing significant crop yields and economic losses. The objective of this study was to determine the mortality, enzymatic antioxidant activity and gene expression of cabbage aphids (<italic>Brevicoryne brassicae</italic> L.) in response to <italic>Trichoderma longibrachiatum</italic> T6 (T6) at different time points from Day 1 to 7 after inoculation. Our results showed that the highest mortality of <italic>B. brassicae</italic> was observed on Day 7 at a concentration of 1 × 10<sup>8</sup> spores ml<sup>−1</sup> (73.31%) after inoculation with T6 compared with the control on Day 7 (11.51%). The activities of the enzymes superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), ascorbate peroxidase (APX), glutathione peroxidase (GPX) and glutathione S-transferase (GST) were increased by 52.98%, 44.77%, 48.26%, 49.39%, 45.13% and 39.67%, respectively on Day 3 after inoculation with T6 compared to the control. Howerver increased days post treatment (dpt) decreased the activities of SOD<italic>,</italic> POD<italic>,</italic> CAT<italic>,</italic> APX<italic>,</italic> GPX and GST enzymes by 20.79%, 21.05%, 13.75%, 20.45%, 25.38%, and 19.76% repectively on Day 7 compared to control. The transcript levels of <italic>SOD</italic>, <italic>POD</italic>, <italic>CAT</italic>, <italic>GPX</italic>, and <italic>GST</italic> genes were increased by 10.87, 9.87, 12.77, 6.22 and 4.07 respectively at Day 3 after inoculation with T6 in comparison to the control. However, the <italic>SOD</italic>, <italic>POD</italic>, <italic>CAT</italic>, <italic>GPX</italic>, and <italic>GST</italic> transcription levels decreased by 0.43, 0.44, 0.35, 0.52 and 0.47 respectively, compared to control at Day 7<italic>.</italic> Our results suggest that the T6 strain has a potential effect on the antioxidant activity and mortality of <italic>B. brassicae</italic> and therefore could be used as a natural biocontrol agent against <italic>B. brassicae</italic> in the future.</p>