This study was conducted to determine the susceptibility of four citrus
rootstock; Sour orange (SO), Volkameriana (VOL), Cleopatra mandarin (CM) and
Troyer citrange (TC) to citrus nematode; Tylenchulussemipenetrans and control
citrus nematodes by using bioagents and plant extracts under both greenhouse and
fieldconditions. In addition to determine the citrus yield (cv. Volkameriana) in Egypt.
Data showed that Volkameriana is the most susceptible rootstock; whereas
Troyer citrange is the least susceptible rootstock to the citrus nematodes under
greenhouse conditions.
Seven treatments (Psudomonasfluorescens, Arthrobotrysoligospora,
Trichodermaharzianum, Origanummajorana,Tageteserecta, Eucalyptus globules, at
different concentrations, and oxamyl (24%)) were used to control T. semipenetrans
under both greenhouse and fieldconditions on citrus.
The most effective treatment in controlling citrus nematodes; T.
semipenetrans was Psudomonasfluorescens whereas the least effective was
suspension of Eucalyptus globules under both greenhouse and field conditions.
Psudomonasfluorescens was more effective in reducing numbers of egg laying
females, number of eggs/ egg-mass and number of second stage larvaein the soil,
whereas the suspension of Eucalyptus globules was the least effective under both
greenhouse and field conditions.
Under greenhouse conditions all treatments led to increase the total fresh
weight of shoots and roots of citrus seedlings especially at the highest
concentration. The application of treatments achieved high decrease in nematodes
population in both roots and soil under both greenhouse and field conditions also,
increased the yield of citrus under field conditions.