الفهرس 
Introduction
Nematode surveyOnly 14 pages are availabe for public view
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Abstract
A survey of peach orchards conducted in Dakahlia, Behira and Menoufyia governorates revealed the presence of nineteen nematode genera i.e. Criconemella, Ditylenchus, Helicotylenchus, Hemicycliophora, Hoplolaimus, Longidorus, Meloidogyne, Paratylenchus, Pratylenchus, Rotylenchulus, Trichodorus, Tylenchorhynchus, Tylenchulus, Xiphinema, Aphele ncho ides, Aphelenchus, Dorylaimus, Psilenchus and Tylenchus. Tylenchulus, Paratylenchus, Tylenchorhynchus , were found to be the most prevalent nematode genera in the three governorates. Although, Helicotylenchus and Meloidogyne showed moderate occurrence, in soil samples collected from Behira, Dakahlia and Menoufyia governorates. Meloidogyne was considered to be the serious pest of peach orchards as it was associated with five out of eight cultivars surveyed and also recorded Meloidogyne from the six soil types examined. The impact of three concentrations of the non-parasite rhizobacterium, Serratia marcescens on egg hatching and mortality percentage of newly hatched juveniles (h) of M incognita indicated that all concentrations tested significantly increased hatching rate as time of exposure increase in vitro. Positive relationship was relatively existed between percentage of hatching and concentrations tested. The incubation of eggs with S. marcescens for 10 days at 10s and 10’ concentrations accelerated hatching rate with values of 105 and 114.7 respectively and exceeded that of the control (78.0). Malformed eggs was also noticed. A positive correlation has been observed between S. marcescens concentration and M incognita mortality. The higher the concentration, the greater percentage of nematode mortality was attained. The 10’ concentration significantly gave the highest percentage of mortality of M incognita juveniles at 48 and 72 hrs exposure period with values of 40 % and 60% as compared with other concentrations respectively. Similar trend was noticed with 108 concentration. The impact of four Egyptian commereial biofertilizers, Biogine , Phosphorine, Rhizobacterine and Microbine and the biocontrol agent S. marcescens alone or in combination with oxamyl on M incognita infecting Balady peach plant cv. Meet-Ghamr indicated that non-parasite rhizobacterium, S. marcescens significantly improved peach plant growth in terms of fresh shoot and root weight ,shoot dry weight, number of shoot branches and leaves.