44 Khaled A. Selim, Mohamed M. S. Nagia and Dina E. El. Ghwas
On the other hand, large woody perennials assistance a parasite likes
dodders and mistletoes, may have endophytic fungi (Suryanarayanan
et al., 2000). Due to the unclarity of endophytes infections, the diversity of the
internal mycobiota is relatively high and a small potential hosts have been
investigated till now (Arnold et al., 2000). Examination of economically
important plants for endophytic fungi till now, every now and again yields
new taxa. Investigations of endophytic fungi are expected to give us a lot of
information for their distribution and diversity. Typically the endophytic
micro-fungi exist as unseen, internal and microscopic hyphae; their existence
proved that, they sporulate seasonally and transient. Detection and isolation of
endophytic fungi need selective methods.
Identification includes always host microscopical examination and usually
need a high degree of taxonomic experience. This is right for isolates that
cannot produce spores or cannot identify their structure therefore, finding the
growth conditions that stimulate sporulation are very important. Furthermore,
the ribosomal DNA (rDNA) gene sequences are used for endoptytic fungi that
neither grow nor sporulate, which can illustrate the phylogenetic position (Guo
et al., 2000). The major block of endophytes ecological studies is the lack of
basic taxonomic information. The issue can be overcome by coordinating the
present databases (nomenclature and host indices); however major biological
overview work is required.
3. ROLE OF ENDOPHYTES IN NATURE
Previously, endophytic fungi have been known as mutualists and it is
much related to virulent pathogens; however their pathogenicty is limited and
developed directly from plant pathogenic fungi. The symbiosis of mutualistic
containing the absences of most cells or tissues, nutrient and chemical cycling
between hosts and fungus, promoted pathosynthetic capacity, induce longevity
of tissue and promoted living of fungus. It is always difficult to distinguish
between pathogen and endophyte as many plant pathogens submit an extended
phase of asymptomatic latent infection before the occurrence of disease
symptoms, also the mutation can alter a pathogenic to a nonpathogenic
endophyte with no influence on their host specify. Latent infection means that
the host infected by the pathogen, however does not show any persists and
symptoms until symptoms are induce to appear as an environmental or
nutritional conditions (Brader et al., 2014).