Bemisia tabaci | Syrian Journal of Agricultural Research SJAR

Bayan Almustafa^*1, Dummar Nammour¹_,and Bassam Odeh ²

1Department of Plant Protection, Faculty of Agricultural Engineering, Homs University, Homs. Syria.
2Homs Research Center, GCSAR, Syria.

(*Correspnding author: Bayan Almustafa, E-Mail :byanalmstfy@gmail.com, Tel: 963936290055).

Received: 10/ 07/ 2025 Accepted: 3/ 09/ 2025

Abstract:

The whitefly (Bemisia tabaci Genn.) is considered one of the most dangerous agricultural pests affecting a wide range of economically important crops, including eggplant in central Syria. It causes significant damage by feeding on plant sap and transmitting viruses. Known for its rapid reproduction, especially in warm and protected environments, its development and population dynamics are strongly influenced by environmental factors. This study aimed to investigate the seasonal abundance of B. tabaci, estimate the number of its generations, and assess the impact of climatic variables on its different life stages (eggs, nymphs, and adults) under field conditions.The research was conducted at the Al-Mukhtaria Research Station (Homs) during the 2023 and 2024 growing seasons. Results indicated the presence of four generations in 2023 and five in 2024. The increased temperatures and relative humidity in 2024 contributed to higher insect activity and reproduction, particularly in the adult stage, which showed a significant positive correlation with minimum temperatures. The three developmental stages were variably affected by climatic factors such as relative humidity, solar radiation, and wind speed, highlighting the importance of these variables in determining optimal pest control timing. The findings suggest that integrating climatic data into early warning systems and integrated pest management (IPM) programs could enhance the effectiveness of whitefly control strategies.

Keywords:Eggplant, Bemisia tabaci, seasonal abundance, climatic factors, number of generations.

Full paper in Arabic: pdf

Rafik Abboud^*(1) Majedah Mofleh⁽²⁾ and Ahmad Mohammad⁽³⁾

(1). Latakia Agriculture Research Center, General Commission for Scientific Agricultural Research GCSAR, Damascus, Syria.

(2). Plant Protection Department, Faculty of Agriculture, Tishreen University, Latakia, Syria.

(*Corresponding author: Dr. Rafik Abboud. E-Mail: abboud.rafeek@hotmail.com).

Received: 17/07/2019 Accepted: 08/12/2019

Abstract

The study was conducted to evaluate the efficacy of the predator Serangium parcesetosum Sicard (Coleoptera: Coccinellidae) in controlling Bemisia tabaci Genn. on tomato and cucumber plants in cages. The experiment included four treatments and 12 replications. The first and third treatments were conducted on cucumber plants and second and fourth treatments were experienced on tomato plants. Adults of B. tabaci were introduced in cages on plants that have six true leaves. Two weeks later, adults of S. parcesetosum were introduced in the first and second treatments at a rate of two adult predators/plant. The release was done three times at weekly intervals. The third and fourth treatments remained predator-free. Leaves were examined weekly, the population of immature stages were recorded (eggs, L1, L2, L3, L4\ 1 cm² leaf) which were taken randomly from the top, middle and bottom of the plants. The predator was not recorded on tomato. The number of whitefly stages increased in treated cages until the sixth week, and then began to decrease from about 20 eggs and 39 nymphs/1 cm² of leaf surface to 11 eggs and 3 nymphs after ten weeks. Population density of the whitefly in the control increased to 219 eggs and 145 nymphs/1 cm² of leaf surface during the same period. Mortality rates of old nymphs were 93.3 and 4.1% after nine weeks for the predator treatment and control, respectively. Results indicated that, S. parcesetosum could be recommended for the control of B. tabaci on cucumber in protected cultivation in Syria.

Keywords: Biological control, Bemisia tabaci, Cucumber, Tomato, Protected cultivation, Syria.

Full Paper in Arabic: PDF