Root-knot nemaode which causes extensive damage to legumes and cerealshas been
reported in many countries. The nematods has been observed on legumes, roots in many
regions of the world, causing swollen root and yield reduction. In order to evaluate the effect of
irrigation interval on reproductive traits of root-knot nematode, and the damage inflictedupon
navy bean, a study was conducted in 2011 in the research greenhouses of Shiraz Islamic Azad
University. Thefactorial experiment was arranged in an RCB design of three replications.
Three factors, including- variety at two levels; irrigation interval at three levels, and
infestationat two levels were considered. Nematode inoculation was conducted at the seedling
stage of navy bean by a number of 2000 eggs plus second stage juveniles per kg of soil in each
pot. Plant growth and nematode reproduction trends were started to be assessed two months
following inoculation. On the basis of the recorded results the effect of irrigation interval on
the whole traits, related to nematode, was significant at a 1% level of probability. The highest
and the lowest number of galls per root, egg mass per root, nematode final population as well
as reproduction traits were recorded for the 48 and 96 hour irrigation intervals respectively.
The two irrigation treatments significantly differed at 5% level as regards the four tested traits.
The results also revealed that varieties at different irrigation intervals responded differently to
nematode damage. As much as the soil moisture content was less, the nematode was more
disabled and plants grew with more vigor. So, maybe one can retard the growth of nematodes
by management of irrigation interval especially when the probability of damage of the
nematode is high, although the economic performance of the crop should also be put into
consideration.