Induction of sporulation in plant pathogenic fungi

Figures & data

Figure 1. Slide culture technique to induce the formation of spores. (A) Sterilized filter paper, sticks, and slide. (B) Add sterilized water on the filter paper to maintain humidity. (C) A small amount of mycelia was inoculated on 0.5 mm × 0.5 mm PDA agar. (D) Cover a sterilized coverslip on the agar block, seal the petri dish, and incubate at the fungal growth temperature for 7–14 days. The coverslip was taken out and observed microscopically.

Table 1. Environmental stimuli for the induction of conidiation in some important pathogenic fungi

Family or genus	Representative species	Environmental stimulus	References
Alternaria	Alternaria spp.	Nutrient limitation	Rotem (1994)
	A. tomato	Temperature	Aragaki (1961)
	A. cichorii, A. solani	Near-UV light irradiation	Charlton (1953), Vakalounakis and Christias (1981)
		Desiccation	Rotem (1994)
	A. alternata, A. dauci, A. solani	S-medium (water agar amended with CaCO3 and sucrose)	Shahin and Shepard (1979), Masangkay et al. (2000)
	A. solani	Scraping	Singh (1967)
Botryosphaeriaceae	Botryosphaeriaceae spp.	2% water agar with sterilized pine needles + near-UV light irradiation	Crous et al. (2006), Wulandari et al. (2009), Glienke et al. (2011)
	Guignardia mangiferae, Phyllosticta capitalensis, P. citricarpa	OMA + near-UV light irradiation	Glienke et al. (2011)
	Phyllosticta spp.	Near-UV light irradiation	van der Aa (1973)
	Phomopsis phaseolorum	Sterilized plant parts exposed to cool-white fluorescent light	Onesirosan (1978)
Fusarium	Fusarium culmorum	Reduced nutritional levels	Larmour and Marchant (1977)

Table 2. Twenty-six successful sporulation-inducing isolates

			Medium
Host	Strain no.	Preliminary identification	Mulberry agar	Pine needle extracts plus 1/10-strengh PDA medium	1/10-strengh PDA medium	CaCO3 water agar
Trachycarpus fortunei	D3-1	Colletotrichum sp.	√		√
Fern sp.	D2-1	Colletotrichum sp.		√	√
Fern sp.	D2-2	Colletotrichum sp.	√ (combined with near-UV irradiation)
Terminalia arjuna	h8-1	Colletotrichum sp.		√	√
Orchidaceae sp.	h86-1	Colletotrichum sp.		√
Orchidaceae sp.	h86-2	Colletotrichum sp.	√			√
Clinacanthus nutans	h53-1	Colletotrichum sp.		√		√
Viburnum odoratissimum	h41-2	Colletotrichum sp.		√
Camellia sinensis	h6-2	Colletotrichum sp.		√	√
Ophiopogon japonicus	h50-2	Colletotrichum sp.		√	√
Orchidaceae	h79-1	Colletotrichum sp.	√		√	√
Michelia figo	h90-1	Colletotrichum sp.		√ (combined with near-UV irradiation)
llex triflora	DY6-2	Colletotrichum sp.		√ (combined with near-UV irradiation)
Gramineae sp.		Colletotrichum sp.		√
Syzygium jambos	h7-1	Celoporthe sp.	√
S. jambos	h7-2	Cryphonectria sp.	√	√
Cymbidium bicolor	h69-1	Phomopsis sp.		√	√	√
Syzygium tephrodes	h18-1	Endomelanconiopsis sp.				√
Cymbidium sp.	h66-1	Fusarium sp.	√	√
Trachycarpus fortunei	D3-1	Microdochium sp.			√
Areca triandra	h30-1	Phomopsis sp.				√
Viburnum odoratissimum	h41-3	Phomopsis sp.		√	√
Caryota ochlandra	h10-2	Phyllosticta sp.		√
Billbergia pyramidalis	h77-2	Mycoleptodiscus sp.		√
B. pyramidalis	h77-1	Mycoleptodiscus sp.	√ (combined with near-UV irradiation)
Trachycarpus fortunei	h34-1	Pestalotiopsis sp.		√ (combined with near-UV irradiation)

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