تقييم كفاءة فطرالمايكورايزا Glomus mosseae في مكافحة مرض تعفن الجذور المتسبب عن الفطر Rhizoctonia solani و تقليل الإجهاد المائي لنبات الذرة الصفراء في الظروف الحقلية

الملخص EN

This study aimed to evaluate the efficiency of mycorrhizae (Glomus mosseae) in controling of root rot disease caused by Rhizoctonia.solani and the effect of water stress on maize plant in order to find out friendly environmental manner to control disease.

Laboratory experiments showed the virulent ability of the R.solani and the percent of the decayed seeds reached to 57%.

The field pots experiment in the field have showed that the plants which were exposed to the water stress at periods of irrigation (2, 4 and 6 days), effected on the plant growth indicators.

where the irrigation period of 4 days gave the best results in dry weight of shoot , root and the rate of available phosphorus , which was 1.50 g , 2.60 g and 0.017(mg.kg-1) respectively, and the irrigation period each 2 days gave the best results in plant height and the rate of total phosphorus in the root, which were 48.77cm and 0.123% respectively.

While the irrigation each 6 days gave the best results only in phosphorus rate in the leaves, which amounted to 0.166%, while water stress factor did not affect (irrigation periods) the percent of the infected roots with mycorrhizae.

The results indicated that the treatment with none-fungus gave an increment in dry weight of shoot and root , plant height , the available and total phosphorus in the leaves and root , also the percentage of mycorhizal infection.

Results also showed that the level of the inoculums of 30 g gave the highest rate of dry weight of shoot (1.200g), compared to control treatment (0.993g) and the highest rate of the dry weight of the root was 1.939g and the highest rate of plant height 47.32 cm compared to control which was 37.97cm and the highest rate of phosphorus in the leaves was 0.183% and the highest percentage of mycorhizal injury 51.11% .

The treatment with 20 g was the superior in the available of phosphorus which was 0.018(mg.kg-1) compared to control treatment 0.011(mg.kg-1).

The results also showed low phosphorus content in the root of all mycorrhaizal inoculum levels of 0.063, 0.095 and 0.097(mg.kg-1) respectively compared to control treatment 0.104(mg.kg-1).