Fig. 6.

Difference in embolism occurrence ratios in metaxylem (M) and protoxylem (P) vessels. (A) Specific xylem-type embolism occurrence according to dehydration periods. Each bar represents the ratio of gas-filled specific-type vessels (M or P) to the total number of corresponding vessels (n=3, 3, 3, 5, 3, and 4 for 0, 2, 3, 4, 5, and 6 d of dehydration). Yellow bars denote embolism ratios of metaxylem vessels, and orange hatched bars indicate embolism ratios of protoxylem vessels. (B) Comparison of embolism ratios in metaxylem and protoxylem vessels with respect to xylem vulnerability (n=21). Unpaired one-tailed t-test results indicate high and moderate significance. Error bars indicate SD. This figure is available in colour at JXB online.