Agricultural Research Center, Plant Protection Research Institute, Department of Scale Insects and Mealybugs Research, Giza, Egyp.
Mansoura University, Faculty of Agriculture, Economic Entomology Department, Mansoura, Egypt.
Braz J Biol. 2024 Aug 12;84:e283233. doi: 10.1590/1519-6984.283233. eCollection 2024.
The cotton or solenopsis mealybug, Phenacoccus solenopsis (Tinsley, 1898) (Hemiptera: Pseudococcidae), infests various host plants in Egypt. A study was conducted to observe the incidence of mealybugs and the possible influences of meteorological variables and plant age on the insect population of maize (single-hybrid 168 yellow maize cultivar) plants in Esna district, Luxor governorate, Egypt, in two consecutive seasons (2021 and 2022). P. solenopsis infested maize plants from the 3rd week of June to harvest, and had three peaks of seasonal incidence/season namely; in the 1st week of June in the 3rd/4th week of July, and the 2nd week of August. Similarly, there were three peaks in the percent of infestations per season. In the first season, the average population density of P. solenopsis per sample was 174.04 ± 16.93 individuals, and in the second season, 156.72 ± 14.28 individuals. The most favorable climate for P. solenopsis population increase and infestation occurred in August in the first season and in September in the second season, while June was less suitable in both growing seasons (as estimated by weekly surveys). The combined effects of weather conditions and plant age are significantly related to the estimates of P. solenopsis populations, with an explained variance (E.V.) of 93.18 and 93.86%, respectively, in the two seasons. In addition, their influences explained differences in infestation percentages of 93.30 and 95.54%, respectively, in the two seasons. Maize plant age was the most effective factor in determining changes in P. solenopsis population densities in each season. The mean daily minimum temperature in the first season and mean daily dew point in the second season were the most important factors affecting the percent changes in infestation. However, in both seasons, the mean daily maximum temperature was the least effective variable in population and infestation variation. This study paves the way for monitoring and early detection of mealybugs in maize; as well as the optimal climatic conditions for its development.
棉粉蚧，也称鳞球粉蚧（Tinsley，1898）（半翅目：粉蚧科），在埃及侵害各种寄主植物。本研究旨在观察在埃及卢克索省艾斯纳地区，两个连续季节（2021 年和 2022 年）中，粉蚧对玉米（单交 168 黄色玉米品种）植株的发生情况以及气象变量和植株年龄对其种群数量的可能影响。棉粉蚧从 6 月第 3 周开始侵害玉米植株，直至收获，且存在 3 个季节性发生高峰/季节，分别为 6 月第 1 周、7 月第 3-4 周和 8 月第 2 周。同样，每个季节的侵害率也存在 3 个高峰。在第一个季节，每个样本中棉粉蚧的平均种群密度为 174.04±16.93 头，而在第二个季节，为 156.72±14.28 头。第一个季节中，最有利于棉粉蚧种群增加和侵害的气候出现在 8 月，而在第二个季节，最有利于的气候出现在 9 月，而在两个生长季节中，6 月的条件都较差（通过每周调查进行估计）。天气条件和植物年龄的综合影响与棉粉蚧种群数量的估算密切相关，两个季节的解释方差（E.V.）分别为 93.18%和 93.86%。此外，它们的影响分别解释了两个季节中侵害率 93.30%和 95.54%的差异。玉米植株年龄是每个季节中决定棉粉蚧种群密度变化的最有效因素。第一个季节的平均日最低温度和第二个季节的平均日露点是影响侵害率变化的最重要因素。然而，在两个季节中，日最高温度是影响种群和侵害变化的最不有效变量。本研究为监测和早期发现玉米中的粉蚧以及确定其最佳发育气候条件奠定了基础。
