DETECTION OF CHITINASES IN POTATO PLANTS FOLLOWING INFECTION WITH THEPOTATO CYST NEMATODES, GLOBODERA-ROSTOCHIENSIS AND GLOBODERA-PALLIDA

Changes in chitinase activity were observed following infection of thr ee potato clones (12380, P55/7 and Maris Piper) with four pathotypes o f the potato cyst nematodes, Globodera rostochiensis and G. pallida. F ollowing invasion, the intercellular fluid of the leaves of all the pl ants tested showed marked increases in exochitinase activity. In contr ast, after removal of intercellular fluid the leaf homogenates showed only a limited increase in endochitinase activity. In roots, endochiti nases were significantly increased in 12380 following invasion by G, p allida Pal and G. rostochiensis Ro1 and Ro5 but not by G. pallida Pa2/ 3. The largest increase in exochitinase activity in the roots of 12380 was observed after invasion by G. pallida Pal. The possible role of t hese chitinases in potato-nematode interactions is discussed.