Ecological Studies and Effect of Different Rates to Nitrogen Fertilizer on Aphis Gossypii Glover (Hemiptera: Aphididae) Infesting Chrysanthemum Morifolium

Abstract

Chrysanthemum morifolium, is one of the most important marketable ornamental and flower plants. The experimental carried out at El - Orman Garden, Giza Governorate, Egypt. The present aimed to studying population fluctuation of Aphis gossypii Glover insect and the effect of different nitrogen rates on the densities of chrysanthemum Aphis gossypii infesting chrysanthemum plants during two
successive seasons from September 2020 to August 2021 and from September 2021 to August 2022. studied using four different species and colors of C. morifolium Plant in Giza Province. Seasonal abundance of The cotton aphids (A. gossypii) and the relation between the population activity, weather factors were studied during two seasons from September 2020 to August 2021 to September 2021 to August 2022 seasons on the Chrysanthemum Plant. At El-Orman Garden, Giza Governorate. data indicated that the total stages of the cotton aphids (A. gossypii) have overlapping two generations; the first one with highest number occurred at the mid of April while the 2ndgeneration occurred in early May. Generally the infestation of The cotton aphids in during season, Sept. 2021 and Aug. 2022, more than during season, Sept. 2021 and Aug. 2022. The data illustrate that aphis gossypii record, 4th and 5th generations on white, red, yellow and pink. Especially, population density to A. gossypii on 4th species to C. morifolium disclosed that white species was more susceptibility where come to first order contrast by other species, in case of Nitrogen fertilization, the results revealed that the lower population of the cotton aphids, A. gossypii (1.08 insects /leaflet) in the treatment of lower nitrogen rate (2 grams N/liter) then the population increased to 1.16 insects /leaflet in treatment of 3 liter N/liter. The 3rd rate of N fertilizer (3 grams N/liter) recorded 1.30 insects /leaflet but the maximum population recorded (1.46 insects /leaflet) in treatment of 5 grams N per liter.