Study On Resistance To Sitobion Avenae(F.) Of Wheat Hybrid Progeny And Electron Microscopic Observation On Leaf Ultrastructure

The physical resistance, as a significant part of whole resistance, plays an important role inresist pests. Some phyical structures, such as pubescence,wax coat and awn of wheat, areimportant facts to estimate its aphid resistance. Both the density and branth of pubescence applyto its aphid resistance. Resistance and susceptible wheat may be similar at the length ofpubescence, but different at marshalling sequence. More needs can be supported by electronmicroscopy to research these phyical structures.This study explores the ultra microstructure of wheat leaves and mean relative growth rateof the Sitobion avenae feeding on selected wheat, including three parental generations and fourfilial generations.The results of MRGR experiment show that it is different in development period, adultweight, average relative growth rate for avenae feeding on different wheats. Wheat various inresistance to S. avenae have a degreen effect on the growth and development of the aphids.The results of electron microscope experiment show that marshalling sequence ofpubescence are very form resistance and susceptible wheat. The stronger the resistance, the morecomplex the arrangement. There are no different between resistance and susceptible wheat inshape of pubescence, however, the sizes can be inequality on the former and be equality on thelatter.These results suggest that the pubescenc is a significant part of the wheat aphids resistance,pubescence who have the characteristics like have a complicated arrangement and a compactconfiguration，uneven size or twisted together own powerful resistance of the aphids.