MARZOUK, I., EL-BAWAB, A. (1999). EFFECT OF SOWING DATE OF BARLEY ON ITS INFESTATION WITH THE CORN LEAF APHID ,Ropalosiphum maides (Fitch)(Homoptera: Aphididae) AND YIELD COMPONENTS. Egyptian Journal of Agricultural Research, 77(4), 1493-1499. doi: 10.21608/ejar.1999.342096
IBRAHIM A. MARZOUK; AHMED M. O. EL-BAWAB. "EFFECT OF SOWING DATE OF BARLEY ON ITS INFESTATION WITH THE CORN LEAF APHID ,Ropalosiphum maides (Fitch)(Homoptera: Aphididae) AND YIELD COMPONENTS". Egyptian Journal of Agricultural Research, 77, 4, 1999, 1493-1499. doi: 10.21608/ejar.1999.342096
MARZOUK, I., EL-BAWAB, A. (1999). 'EFFECT OF SOWING DATE OF BARLEY ON ITS INFESTATION WITH THE CORN LEAF APHID ,Ropalosiphum maides (Fitch)(Homoptera: Aphididae) AND YIELD COMPONENTS', Egyptian Journal of Agricultural Research, 77(4), pp. 1493-1499. doi: 10.21608/ejar.1999.342096
MARZOUK, I., EL-BAWAB, A. EFFECT OF SOWING DATE OF BARLEY ON ITS INFESTATION WITH THE CORN LEAF APHID ,Ropalosiphum maides (Fitch)(Homoptera: Aphididae) AND YIELD COMPONENTS. Egyptian Journal of Agricultural Research, 1999; 77(4): 1493-1499. doi: 10.21608/ejar.1999.342096
EFFECT OF SOWING DATE OF BARLEY ON ITS INFESTATION WITH THE CORN LEAF APHID ,Ropalosiphum maides (Fitch)(Homoptera: Aphididae) AND YIELD COMPONENTS
1Plant Protection Research Institute, Agricultural Research Centre, Dokki, Giza, Egypt
2Field Crops Research Institute, Agricultural Research Centre, Dokki, Giza, Egypt
Abstract
Field experiments were conduced at El-Giza Research Station during the two successive seasons (1995/1997)to determine the effect of sowing date of barley on its infestation with the corn leaf aphid, Ropalosiphum maides. (Fitch) (Homoptera: Aphididae) and yield components. Testing sowing dates were 23/11, 8/12 and 23/12 in the first season and 26/11, 11/12 and 26/12 in the second one. For both seasons of investigation, aphids colonized barley plants in the early stages of their life in negligible number. The mean total numbers of aphids/tiller in 1995/96 was comparatively low for the three sowing dates(5.52,4.64 and 2.75, respectively) comparted to that for 1996/97 (40.71,23.46 and 13.68, respectively). Peaks of infestation occurred at mean weather conditions of 10-11°C and 63-73% R.H.Both biological and grain yield were affected under heavy aphid infestation. The first sowing date showed the highest significant values of biological and straw yield compared to the other two tested sowing dates. The highest grain yield was took place at the second sowing date.