Chapter Four

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living organism, obtaining nutrients from it and being harmful to the organism (the
host) by causing diseases (Raven et al., 1992). An endophyte is an organism living in
healthy plant tissue but causing symtompless infection (Petrini, 1991). A saprobe is an
organism that utilizes non-living organic material as food, commonly causing its
decay (Hawksworth et al., 1983; Cooke and Rayner, 1984; Dix and Webster, 1995).
However, studies of endophytes have showed that they can switch between one mode
of nutrition and another during their life cycle (Boddy and Griffith, 1989; Fisher and
Petrini, 1992; Sridhar and Raviraja, 1995), thus utilizing both living and dead tissue.
2.4 Ecology of Saprobic Fungi
Several saprobic fungi have been examined on dead plant tissues of several
plant species in different geographical regions worldwide (Table 2.4).
2.5 Litter Fungi
Fungal diversity assessments have been carried out worldwide on various
plant substrata, e.g. bamboo, leaf litter, palms, wood and submerged wood (Fröhlich,
1997; Dalisay, 1998; Taylor, 1999; Tsui, 1999; Yanna et al., 2001; Parungao et al.,
2002). Tropical rainforests comprise a great variety of tree species that produce high
amounts of leaf litter (Cooke and Rayner, 1984). Few investigators, however, have
attempted to measure the abundance in the diversity of microfungi species inhabiting
tropical leaf litter (Bills and Polishook, 1994, Promputtha et al., 2002, 2004a, b, c).
Decomposers are stratified within the forest floor, with some species colonizing only
fresh litter and others restricted to soil organic matter (Lodge and Cantrell, 1995).
Parungao et al. (2002) studied the diversity of fungi on rainforest litter in