Stirling and Mankau (1978b) studied the association of D. oviparasitica with tomato plant roots, where incorporation of roots into the soil or the use of rhizosphere soil enhances the chances of detecting the fungus. The number of eggs that hatch varies with different groups of egg masses and with environmental factors such as soil moisture, leaving various numbers of eggs available for parasitism. Egg masses from greenhouse cultures usually contain large numbers of mature eggs that escape parasitism because they hatch soon after being added to soil. Although the presence of D. oviparasitica can usually be determined by this method, it is unsatisfactory because parasitized eggs are used to estimate the seasonal variation in the activity of the parasite or to compare levels of parasitism in different fields. Fungal activity under tile field environment was evaluated by placing soil and roots in porous ceramic tubes, bags of fine nylon screening, or other materials that allow free movement of water and gases, and burying the containers in the field. Single-spore isolates cultured on YPSS agar were compared with isolates recovered from parasitized eggs and shown to be equally effective in parasitizing Meloidogyne eggs on agar. D. oviparasitica was often isolated from peach and grape roots with this method. However, its slightly curved triseptate conidia are easily differentiated from those of D. oviparasitica, which are straight and 5-7 septate. also occurs on roots with this technique, and under the dissecting microscope, it may be confused with D. oviparasitica. If small quantities of soil are used instead of roots, D. oviparasitica is rarely observed. Under these conditions, D. oviparasitica is probably not nutritionally dependent on nematode eggs, but it apparently grows saprophytically on roots and on cornmeal agar. The fungus often sporulates prolifically on roots, and occasionally sporulates on agar. Conidia do not always occur on repeated samples from the same root system, but the reasons for this variability are not known. Organisms colonize roots and agar, predacious fungi begin to decline, and conidia of D. oviparasitica can often be seen protruding from roots ( Mankau, 1975). Also, the disappearance of hyphae in eggs following destruction of the embryo sometimes makes it difficult to identify the original parasite. This method gives a direct indication of the number of eggs invaded by D. oviparasitica, but it does not differentiate between parasitism of viable eggs and saprobic growth in dead eggs. Inoculated media are examined daily for D. oviparasitica. Clumps of parasitized eggs were washed in sterile water and added to cornmeal agar (cornmeal infusion, 50 g agar, 15 g water, 1 L), glucose-peptone agar (glucose, 10 g peptone, 10 g agar, 16 g water, 1 L), or YPSS agar (yeast extract, 4 g K2HPO4, 1 g MgSO4–7H20, 0.5 g soluble starch, 20 g agar, 16 g water, 1 L). Stirling and Mankau (1978a) collected the gelatinous matrix of Meloidogyne egg masses from host plants in the field and partially dissolved by treating in 1% NaOC1 for about 2 min, and eggs were examined for parasitic fungi. By combining the ITS sequence with morphologic characteristics, a new anamorphic species was described and illustrated together with its teleomorph. Conidia were elongated ellipsoids, 1–2 septate, mostly 1 septate. Conidiophores were either not branched or occasionally branched, bearing divergent sterigmata on the tip with a single conidium on each. (2009) isolated D. alba, a new species from the ascospores of Orbilia alba collected in Wenshan County, Yunnan Province, China. Therefore, it is described as a new anamorphic species, D. coccinella. Comparison of its morphologic and biologic characters and analysis of sequence data of the rDNA in ITS region suggest that the fungus is a separate species. Simple conidiophore that bears a single, cylindrical, 1-7- septate conidium with a round distal end, a monoblastic conidiogenous cell, cylindrical, and absence of nematode-trapping capability distinguish this anamorphic fungus from other Dactylella species. coccinella from the teleomorphic fungus Orbilia coccinella and described it as a new anamorphic species. Sterling and Mankau (1978) isolated D. oviparasitica from root knot nematode egg masses ( Meloidogyne spp.). Sunitha, in Beneficial Microbes in Agro-Ecology, 2020 3 Isolation of Dactylella
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