One day I got a call from Dr.Yadu Kumar of cashew research station,Puttur.He informed me that one Dr.Nagesh is visiting your plot tomorrow.I do not remember the date.The next day Dr. Nagesh came to my plot. He said that he is from P.D.B.C.Bangalore.That institution is established by the central government and is trying to find solutions to the farmers problems in organic way.Further he said that there is a few nematodes which eats root grubs and he want to test it in my plot. Nematodes were not a new one, but quality in commercial availability may not be superior . He brought two types of nematodes,the names of which I do not remember.Although he penned it down in a paper for me ,it was not readable for me.He asked me to            observe the treated plants periodically and collect the dead grubs if I got it.Dr.Shailesh was also with him. Ravi was assisting their work.
In my plot he applied one type of nematode . I showed him another plot in Markanja.That plot belongs to Mairaje Ashok Bhat and his plot has Lepidaphora grub.Dr.Nagesh applied another nematode in Ashok Bhat's plot.
After around a week I got a dead grub in the plot.In addition to plant application we applied it in a plastic basket where we put some live grubs with soil. Regularly I found one or two dead grubs in the basket.But I could not found any dead grubs in the plot further.I send him the photos of the dead grub and he confirmed it for nematode killings.

But in the plot of Ashok Bhat it was another story. He said that only one grub died in about a week but no other grub mortality could be seen further.
They came again after a few months and collected the soil samples .They afterwords informed me that nematodes was well established in the plot .It will develop itself and kill whatever root grubs found in its way.
I don't know what to say. I had seen dead grubs in the plastic basket. The nematodes took almost a month to kill about 15 grubs in the basket.I think that the process may be even slow in the plot.Even though it kills grubs what dosage we may have to apply to get quick result in the plot? Dr.Nagesh says that we must flood the plot initially.But what may be the cost? Don't know.But anyhow it survives in the plot if moister condition is maintained.Hence in my opinion it is best to treat the plot with chemicals first and after we control the grubs we can apply nematodes to prevent the recurrence of the grub problem.