تأثير نيماتدوا تعقد الجذور meloidogyne javanica على نمو بادرات فول الصويا بأعمار مختلفة و التداخل بين الفطرين rhjzoctania solani و macorphomina

Abstract AR

Three experiments were conducted to study the effect of the root- knot nematode Meloidogyne javanica population densities 0, 1000, 2000, 4000, 6000, 8000 and 10000 juvenile /pot on soybean seedlings at age 0 (seeds), 1, 2, 3 or 4 weeks, and the interaction of this nematode with the fungal pathogens R.

solani and M.

phaseolina on the growth of soybean plants (cv.

Lee–74), 60 days after inoculation in plastic pots under lath house conditions.

The results showed a decrease in all studied plant growth characters but without significant differences at the population density of 1000 juvenile/ pot, whereas the damage was severe with significant differences when the nematode population density increased.

The nematode caused significant decrease in plant characters when inoculated at 0 (seeds),1 and 2 weeks old seedlings, whereas when 3 or 4 weeks old seedlings were inoculated, no significant effect on plant growth was obtained compared to the control plants.

The interaction effect of this nematode with both pathogenic fungi R.

solani and M.

phaseolina caused significant decrease in plant height and dried plant weight; especially when nematodes were inoculated one week before both fungi, and rate of severely damaged plants reached 47.62 and 64.62%, respectively, and was significantly more than the other treatments.