Recovery Characteristics of Cry1Ac Endotoxin Expression and Related Physiological Mechanisms in Bt Transgenic Cotton Squares after High-Temperature Stress Termination

High-temperature stress reduces the endotoxin expression of insecticidal gene (Cry1Ac) in transgenic Bacillus thuringiensis (Bt) cotton and affects nitrogen metabolism. However, its effects on Cry1Ac after high-temperature termination remain unclear. In order to investigate effect proteins Bt squares, conventional Sikang-1 cultivar hybrid Sikang-3 were used as experimental materials. The potted plants squaring stage moved an artificial climatic chamber at 38 °C for 72 h 96 2017 2018, respectively, climate where control located (at 27 °C). Then, squares collected measure protein concentration metabolism physiology 0, 12, 24, 48, termination, respectively. could be recovered corresponding level a longer recovery time was required period increased. Therefore, degree can predicted according duration stress, which may provide reference rational Helicoverpa armigera related pests production.