The use of some relatively safe compounds for the control of citrus leaf miner Phyllocnistis citrella staint [electronic resource].

Includes references.

The efficiency of eight compounds representing different chemical groups was evaluated against the citrus leafminer P. citrella larval population on navel orange trees. At the recommended rates, the tested compounds suppressed the level of infestation to different degrees according to the nature of the compound, the rate of use and the time elapsed after spraying. As an average of the two sprays, three weeks each, ? cyhalothrin, as a potent pyrethroid, was the most effective compound giving 73.7% reduction, followed by the mixture of abamectin + Kz-oil (71.5%) and then chlorpyrifos methyl (59.0%). This effective group was considered as the first category of the tested compounds. The second category includes; Kz-oil, pyriproxifen + Kz-oil and azatin. They displayed moderate effects amounted to 47 , 44.7 and 43.0% reduction in infestation through the two sprays, respectively. The remaining products (pymetrozine and bio-dux) may be regarded as ineffective in reducing the leafminer incidence under the prevailing experimental conditions. The bioresidual activity of the tested compounds, even with the potent pyrethroid, did not exceed more than two weeks (for the best cases). Thus, the frequent application would be necessary, particularly when non traditional compounds were used. The efficiency of the treatments was evaluated by visual estimation of infested or non-infested leaves, intensity of larval infestation and the larval vitality. The present results clarify that assessment of the test compound using a certain criterion does not conflict with other criteria. Despite of offering more accurate and reliable data by the last two criteria, the order of insecticidal efficacy by using the three tested criteria seems to be almost similar.

Summary in Arabic.

1