تأثير موعد الزراعة في تعداد حشرات المن و الأعداء الطبيعية المصاحبة لها على نباتات الفول البلدي (Vicia faba L.)‎ في مصر

Abstract EN

Aphids are major constraints to faba bean production in Egypt.

Faba bean is attacked by two aphid species, Aphis craccivora Koch, and A.

fabae Scop., the latter occurs rarely.

A study on the impact of planting date on aphids’ population and their associated natural enemies on faba bean plants was carried out at Sids Research Station (Beni-Suef Govemorate) during 1992/93 and 1993/94 seasons.

Data were collected weekly throughout the growing season using visual counts, and statistically analyzed.

Results showed that aphids’ population reached its peak (29.6 and 42.1 aphid / plant) by mid-March in the two seasons, respectively.

The population was relatively higher in early planting than the late one, but without significant differences.

Six groups and /or species of aphidophagous predators were recorded associated with the aphids on faba bean plants during the study.

Predators’ population reached its maximum (43 and 96 individual/100 plants) during the second half of March in the two seasons, respectively.

Highly significant differences were found between predator populations in the two planting dates during the two seasons of the study.

Four species of internal parasitoids were also recorded on A.

craccivora on faba bean plants.

Highest percentage of parasitism (32%) was estimated during the first week of March in season 1993/94.

No significant difference was found between percentages of parasitism in the two planting dates throughout the study.