Research Article
Hamdy A Salem, Shadia E Abd
Abstract
Four experiments were conducted at Embaba, Giza Governorate by planting beans four times during 2011, 2012 and 2013 to assess the annual variation in population of Melanagromyza phaseoli attacking bean plants Phaseolus vulgaris (L.) in relation to certain climatic factors, synchronization of plant age with insect counts, generation numbers, and injury on plants. Obtained results cleared that adults and larvae of this fly attack plants as soon as seedlings emergence in all growing seasons. In spring 2011, adult females reached highest counts 1.17, 1.17 and 1.1 individual/ sweep at 12th April, 10th May and 7th June, respectively. Their larvae reached highest 2.2 and 15.33 larvae/leaf at 26th April and 31st May. The highest tunnels number during season was 26.87 tunnel/leaf. In summer 2011, larvae reached highest counts 1.4, 29 and 2.3 larvae/leaf at 5th July, 23rd August and 20th September at temperature 27.17, 29.84 and 27.97°C and relative humidity 54.14, 54.57 and 57.71%, respectively. During summer 2012, both adults and larvae reached its highest three times, larvae were 1.9, 4.87 and 7.2 larvae/leaf. Tunnels number was 11.07/leaf in highest case. Leaf miner population was rather low during winter 2012/2013. Capabilities of insect to produce progeny and to injure plants were discussed. Insect produced three generations/ growing season. Temperature and relative humidity revealed their presence inside the optimum range for the insect activity. Plant age had positive relationship with larvae counts in spring and summer seasons. Management program must be directed against insect during period 39-74 day of plant age.