The endophytic fungal community in leaves of a coastal redwood population diversity and spatial patterns

Abstract
SUMMARY: Leaf endophytic fungi were isolated from 1 to 12‐yr‐old leaves of mature trees and basal sprouts of coastal redwood [Sequoia sempervirens (D. Don ex Lamb.) Endl.] in a redwood forest in Central California. Almost all samples yielded at least one species. The two most frequent species were Pleuroplaconema sp. and Cryptosporiopsis abietina Petrak. Among isolated taxa are endophytic generalists, species previously known as pathogens and a possible specialist. Species composition in leaves of progressing age in single branches revealed a patchy pattern of leaf colonization without an obvious sequence of succession. Changes in diversity and equitability in the endophytic community with leaf age are linked with differential distribution of some species in young versus old leaves and the increase in species richness in 4‐ and 5‐yr‐old leaves. The endophytic communities from leaves of trees and sprouts were generally similar, but with important differences in species richness and in distribution of Pleuroplaconema sp. and Pestalotiopsis funerea (Desm.) Stey. Principal component analysis based on endophytic frequency also indicated closeness of trees and sprouts as groups, but clearly separated each tree from its sprout. Differential susceptibility between trees and sprouts to endophytic infection is suggested on the basis of their endophytic communities.