高压静电场对小麦叶片保护酶系统及麦长管蚜种群动态的影响

为明确高压静电场胁迫小麦种子对其叶片以及麦长管蚜Sitobion avenae Fabricius产生的影响。测定了小麦苗期叶片及麦长管蚜体内抗氧化酶(SOD,POD,CAT)的活性,并采用盆栽种群实验研究了麦长管蚜的种群动态。实验结果表明:(1)在未被麦长管蚜取食的小麦叶片中,SOD和POD活性最大值均出现于4 k V/cm处理组,且与对照组差异显著(P0.05),CAT活性在未被取食的叶片中无显著差异(P0.05);而被取食过的叶片中,4 k V/cm处理组的SOD和POD活性均显著低于对照组(P0.05),而CAT活性结果显示4 k V/cm和6 k V/cm处理组均显著低于对照组(P0.05)。(2)静电场处理组中麦长管蚜的SOD和CAT活性均显著高于对照组(P0.05),但POD活性均显著低于对照组(P0.05)。(3)种群动态和逻辑斯蒂模型参数显示4 k V/cm处理组的小麦环境容纳量(K)最小。研究的创新点在于对影响麦长管蚜的介质(小麦)的抗氧化酶活性进行了测定,进一步明确了高压静电场对动植物的影响,说明了4 k V/cm是影响小麦和麦长管蚜的关键强度,为高压静电生态控蚜提供了新思路。

Effects of high voltage electrostatic fields on protective enzyme activity in wheat plants and on the population dynamics of Sitobion avenae fabricius (hemiptera:aphididae)

Sitobion avenae (Fabricius) (Homoptera: Aphididae) is one of the most common pests of wheat. It damages plants by ingesting sap from ears, stems, leaves, and other tender plant parts. It is also known to transmit viruses (e.g., barley yellow dwarf virus) during feeding, thereby reducing wheat yield and quality. High voltage electrostatic fields (HVEF) are reported to influence a wide variety of biological and physical systems. For example, reports of several studies state that HVEF affected plant physiology such that the sprout rates of seeds were improved. Moreover, in agrophysics, electrostatic charging has been used to improve targeting and efficacy of agricultural sprays. Organisms showing aerobic metabolism face constant risk from reactive oxygen species (ROS), such as the superoxide radical (·O^-₂), hydroxyl radical (OH·) and hydrogen peroxide (H₂O₂). The function of protective enzymes includes avoidance of unwanted cellular cytotoxicity and oxidative damage by regulating the production of ROS. In order to explore the effects of HVEF on S. avenae and wheat plants, activities of protective (i.e., anti-oxidative) enzymes such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were examined in wheat leaves and aphid individuals. To evaluate the impact of HVEF on the aphids more accurately, the population dynamics of S. avenae was also investigated. The results showed that the activities of anti-oxidative enzymes were affected by HVEF in both plants and aphids. In undamaged leaves, higher SOD and POD enzyme activities were observed after 4 kV/cm treatment, compared to the control group (P < 0.05), but the CAT activities showed no significant change (P > 0.05). In damaged leaves, SOD and POD activities of 4 kV/cm treatment were significantly lower than those of the control (P < 0.05). CAT activity for treatments with 4 kV/cm and 6 kV/cm were significantly lower than those of the control (P < 0.05). When compared with the control, SOD and CAT activities of S. avenae in all the treatment groups were significantly higher (P < 0.05), while POD activities were significantly lower (P < 0.05). The population dynamics and logistic model parameters showed that the 4 kV/cm treatment resulted in the lowest carrying capacity for S. avenae. Therefore, it is reasonable to conclude that 4 kV/cm is the key intensity for wheat and wheat aphids. In this research, the effects of HVEF on anti-oxidative enzyme activities in wheat were evaluated, and its impact on both animal and plant was further clarified. As is well known, chemical control is often used within an Integrated Pest Management (IPM) program in order to keep pest numbers below the economic threshold. However, farmers often blindly increase the quantity and frequency of insecticide usage to prevent pest damage. Our research showed that seed treatment with HVEF had a range of indirect effects on anti-oxidative enzymes in wheat plants, and on the population dynamics of S. avenae, thus it may provide a new tool for aphid control. Additional research is needed to assess its effects on wheat aphids under field conditions. After further risk assessments, we may find a new approach for ecological control of aphids with HVEF.