Susceptibility of Some L. Cultivars to pv. .

Bacterial blight of hazelnut ( L.) is caused by pv. (Xac).

Micropropagation of pear (Pyrus sp.).

Elements of micropropagation include establishment of shoot tip cultures, proliferation, rooting, and acclimatization of the resulting plantlets. The wide genetic variation in Pyrus makes micropropagation challenging for many genotypes. Initiation of shoots is most successful from forced dormant shoots or from scions grafted onto seedling rootstocks to impose juvenility.