Two trials were carried out under field microplots conditions during April-
August 2015, to study the effect of soil treatment (five days prior to planting) with
decomposed and non decomposed residues of oyster mushroom cultivation (OMC)
at 500g/m2, supernatant (S) of Bacillus thuringiensis (Bt) alone and their
combinations at the half dose (250g/m2) and concentration (S/2), with a
comparative treatment by the chemical nematicide Vydate® L. (Oxamyl 24% SL) at
the recommended dose (5 liters/feddan) on the management of the cyst
(Heterodera goldeni) and root-knot (Meloidogyne incognita) nematodes infecting
rice plants cv. Sakha 101. All treatments greatly (P=0.05) reduced the numbers of
cysts of H. goldeni, root galls and egg masses of M. incognita on rice plant roots as
compared to the control plants infected with either nematode species alone. Of the
tested treatments, Vydate® L. provided the highest reduction (90.02%) of H. goldeni
cysts, followed by the combination of residues of OMC decomposed for 4 weeks
and supernatant (S/2) of Bt (84.11%), while the combined treatment with non
decomposed residues of OMC and supernatant (S/2) of Bt gave the lowest one
(59.15%). Other treatments recorded 66.1-75.04% reduction of cysts. Similarly,
Vydate® L., supernatant (S) of Bt (alone) and residues of OMC decomposed for 4
weeks (alone and their combination with supernatant (S/2) of Bt) showed the
maximum reduction of root galls (79.17-88.17%) and of egg masses (80.02-
88.01%) of M. incognita with no significant differences between them. Other soil
applications gave 66.54-72.08% reduction of root galls and 61.1-68.56% of egg
masses On the other hand, all treatments significantly increased dry weight of rice
plants (25.44-80.96%) and improved spikes yield/plant (44.5-173.0%) as compared
to the control ones infected with H. goldeni only. Likely, these treatments resulted in
valuable increase (28.43-75.02%) of total dry weights and 61.2-163.6% increase of
yield of spikes/plant, as comparing to those infected with M. incognita only. It is
worthy to note that residues of OMC decomposed for 4 weeks (alone and their
combinations with supernatant (S/2) of Bt) appeared to be effective as 50.5 – 62.8%
Egypt. J. Agronematol., Vol. 14, No.1, PP. 62-77 (2015)
Sherin F. Awd-Allah and Amr A. El-Sherbiny
Egypt. J. Agronematol., Vol. 14, No. 1, (2015)
63
of Vydate® L. in controlling H. goldeni, whereas supernatant (S) of Bt, residues of
OMC decomposed for 4 weeks (alone and their combination with supernatant (S/2)
of Bt) found to be as effective as 60-70% of Vydate® L. in managing M. incognita on
rice plants.