关键词: 马铃薯块茎蛾, 物理因素, 化学因素, 产卵行为

Abstract:

【Objective】The objective of this study is to determine the effect of combination of chemical and physical factors on oviposition behavior of potatoworm (Phthorimaea operculella), and to provide a basis for the development of behavior regulation technology of P. operculella.【Method】Tubers were treated with different methods: (1) soaked in heptanal, cineole solution and then dried, (2) wrapped with cotton gauze, or with cotton gauze loading tuber juice, respectively, then oviposition behavior parameters (including landing times, arresting time, ovipositor-probing times, amount of eggs) of mated females on the tubers were observed at the dark-phase (red light intensity: 1.0-1.5 lx) under the environment-controlled conditions of temperature (27±2)℃, relative humidity 50%-70%, and photoperiod 14L:10D.【Result】Females would arrest for longer time (arresting time), and more eggs would be deposited on the surface of the tubers when heptanal solution (0.5 mg·L^-1) was applied onto the surface of tubers, but the times of ovipositor-probing and landing did not increase significantly. Significant reduction in arresting time, landing times and ovipositor-probing times, and more egg-deposition, were observed when heptanal solution at the concentration of 30 mg·L^-1 was applied to the tuber surface. More eggs were laid on the surfaces of tubers, and no significant change in oviposition behavior (arresting time, landing times and ovipositor-probing times) occurred when cineole solution (6 mg·L^-1) was applied. Application of cineole solution at the higher concentration (30 mg·L^-1) would result in significant reduction in arresting time, landing times and ovipositor-probing times, and in more egg deposition outside the tuber. When tubers were wrapped with cotton gauze, more eggs were deposited on the tubers, the times of landing and ovipositor-probing decreased significantly, but no significant difference in arresting time appeared. Similar oviposition behaviors were observed when tubers were wrapped with cotton gauze loading tuber juice. Compared with the blank control, the treatment (tubers + cotton gauze loading heptanal (0.5 mg·L^-1)) led to more eggs deposition and longer arresting time, and to significant reduction in times of ovipositor-probing and landing. Compared with the single use of heptanal (0.5 mg·L^-1), it could significantly reduce ovipositor-probing times and landing times, and at the same time, it could significantly increase the amount of eggs on the tuber and the total amount of eggs. Compared with the single use of cotton gauze, there was no significant difference in each index.【Conclusion】Heptanal can stimulate mated female P. operculella to oviposit in more intensive time. At the concentration of 30 mg·L^-1, heptanal will repel the females from the treated potato tuber; at the concentration of 0.5 mg·L^-1, heptanal will show an attractive effect on mated female moths. Cineole (30 mg·L^-1) only has repellent effect on moths, while wrapped with cotton gauze, cotton gauze soaked in tuber juice, cineole solution (6 mg·L^-1) only show stimulating effect on oviposition of females. These results indicate a co-attractive of combination of the chemical stimulus (0.5 mg·L^-1 heptanal) and the physical stimulus (cotton gauze).

Key words: potato tuber moth (Phthorimaea operculella), physical factor, chemical factor, oviposition behavior