Date : 2017/02/22
الدكتور/ محمد عمر زائد الباشا
Natural abundance of the leaf miner L. bryoniae (Kaltenbach) was studied on four winter host plants [broad bean (Veciafaba), pea (Pisum sativum) , mallow (Malva sylvestris) and snow thistle (Sonchus oleraceus)] in Alejelat region . L. bryoniae showed low populations in December on all studied host plants except broad bean. then ,developed high populations in February and march then the population decreased till the end of the growing season.
L. bryoniae recorded three peaks of abundance on all host plants, except broad bean(4 peaks) the highest peak recorded 104, 260, 156 and 222 individuals/ 100 infested leaflets on broad bean, pea, mallow and snow thistle respectively . The highest average numbers occurred in February on all host plants, except broad bean recording 206.0 ± 57.0, 99.5 ± 48.9 and 146.8 ± 30.8 individuals/ 100 infested leaflets pea, mallow and snow thistle ,respectively and 59.0 ± 36.6 individuals/ 100 infested leaflets on broad bean recorded on December . On the other hand the lowest monthly average numbers occurred in April recording(19.5 ± 6.4, 39.5 ± 12.0, 10.0 ± 1.4 and 9.5 ± 3.5individuals/ 100 infested leaflets) on Broad bean, Pea, Mallow and Snow thistle respectively.