Population Fluctuations of Tomato Leaf Miner Tuta absoluta and its Associated Predator True Spiders in Egyptian Tomato Fields

Tomato is one of the most important Egyptian vegetable crops. Its infestation by Leaf miner Tuta absoluta (Meyrik) results in a considerable economic loss. Therefore, the current study aims to monitor the population fluctuations of Tuta absoluta larvae as well as true spiders as possible predators. Tuta-lure 0.5mg/capsule pheromone efficiency for monitoring the male insect was tested during two subsequent tomato seasons 2014 and, 2015. Direct examination of tomato leaves revealed a consistent fluctuation pattern of both the insect larvae and the true spiders in the two seasons. Insect larvae peaked on the mid of June having (65 larvae/10 plants) while the true spiders peaked one week later having (5 spiders/10 plants) in both seasons, respectively. The observed insect larvae population reduction accompanied with an increase in true spiders population during the midseason may reveal a possible predation relationship between them. The afterward detected declining of both populations, may be attributed to the initiations of plant dryness prior to the end of the season. The current study strongly emphasises the importance of phermone traps as an effectitve and powerful predicting method for early pests warning.