Abstract: :The cereal cy st nematode disease and it s inf luence on seedling g row th in w heat w ere studied in this paper .The typical symptom of the disease appeared that root kno ts(nematode g all) are formed at branching part of roots .The resul t of investig at ion on roo t kno ts caused by the nematode disease show ed a highly sig nificant negative correlation between root knot densities and seedling grow th vigor in w heat .As roo t knot density g radually increased from 0.21 to 1.83 , the height of main stem , length of roots , no .of tiller , leave and secondary root per plant have decreased by 27.5 %-45.4 %, 8.0 %-71.9 %, 4.3 %-77.0 %, 7.9 %-65.7 % and 1.3 %-61.6 %, respectively .When the density reached 4.22 above , the seedlings becoming very w eak and yellow can no t produce tiller and secondary roo ts and died early .

Key words: Wheat , Heterodera avenae w oll , Root knot densi ty , Grow th vigor

CLC Number: 

• S35.12