تأثير النتروجين و النحاس في مرض اللفحة البكتيرية المتسبب عن Xanthomonas sp. و صفات نمو نبات البصل Allium cepa L.

Abstract EN

This study was conducted to isolate and identify Xanthomonas bacteria which causing blight of bacterial diseases on Allium cepa L.

plant, and resistance this bacteria by using nitrogen and copper fertilizer.

Xanthomonas bacteria was identified according to microscopic and biochemical characteristics.

Field experiment was carried out by planting white onion bulb; four levels of nitrogen fertilizers were applied to soil (0, 60, 80 and 100 kg N/ha) and three levels of copper sulfate (0, 10 and 20 mg Cu/L.) by foliar application.

Two treatments of Xanthomonas inoculum were used (YDC medium without bacteria, Xanthomonas inoculum).

Nitrogen level of 100 kg N/ha gave the highest average of the most growth characteristics, plant height, leaf length, number of leaves and total yield.

The copper level of 10 mg Cu/L.

gave the highest average of shoot and yield characteristics.

Bacterial inoculum affected decreasing of growth and yield as compared with plant without inoculation.

The treatment of 100 kg N/ha with 10 mg Cu/L.

and without inoculation with Xanthomonas gave the highest value of the most of growth and yield characteristics.