Hypersensitive reactivity of various host and nonhost plant leaves to cell wall components and soluble glucan isoalted from Phytophthora infestans.

Abstract

Cell wall components (CW) and water soluble glucan (WSG) from Phytophthora infestans, that have been known to elicit and suppress the hypersensitive response of potato tissue, respectively, were applied to leaves of various host and nonhost plants by rubbing with carborundum to study how they respond hypersensitively to the fungal components. Leaves of Solanaceae plants: potato, tomato, sweet pepper, egg plant, red pepper, datura, and Japanese bladder cherry; Leguminosae plants: soybean, kidneybean, garden pea, broad bean, and cowpea; and Lileaceae plants: onion, Welsh onion, and white trumpet lily showed necrotic lesions 24hr after treatment with CW. On the contrary, leaves of Solanaceae plants: tobacco; Chenopodiaceae plants: goose-foot, white-goose-foot, spinach, and beet; Compositae plants: chrysanthemum, garland chrysanthemum, and lettus; Cruciferae plants: cabbage, chinese cabbage, turnip, and radish; Graminea plants: rice, barley, wheat, and corn; and Rosaceae plants: strawberry, Japanese pear, and rose did not show any visible necrotic cells within 48hr after the treatment with CW. Red pepper and Japanese bladder cherry (Solanaceae), soybean and cowpea (Leguminosae) and white goose-foot (Chenopodiaceae) showed almost the same necrotic lesion by treatment with WSG as those by CW. In the cases of plant leaves in which necrotic lesions were elicited by these fungal components, an abnormal leakage of electrolytes occurred within 5 hr after treatment with them. These resuslts suggested that specific families of plant have a nature to respond hypersensitively to the cell wall components and water soluble glucan of P. infestans regardless of host or nonhost relationship.