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Techniques

A Microinjection Technique for Conidia of Erysiphe graminis f. sp. hordei. Hideyoshi Toyoda, Laboratory of Plant Pathology, Faculty of Agriculture, Kinki University, Kowakae 3-4-1, Higashi-Osaka 577, Japan; Yoshinori Matsuda, Ryuzo Shoji, and Seiji Ouchi. Laboratory of Plant Pathology, Faculty of Agriculture, Kinki University, Kowakae 3-4-1, Higashi-Osaka 577, Japan. Phytopathology 77:815-818. Accepted for publication 16 October 1986. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/Phyto-77-815.

A microinjection technique was adapted to conidia of Erysiphe graminis f. sp. hordei. By using glass pipettes (outer tip diameter of 0.1 ?m), silicon oil was effectively injected into conidia on an agar layer or on barley coleoptile inner epidermis under a constant injection pressure. Successful injection was easily confirmed by light microscopy because injected silicon oil formed a light-scattering, spherical droplet within conidia. When silicon oil was injected for 3 sec, droplets were 1 ?m in diameter and did not affect germination or formation of appressorium or haustorium of the conidia. Moreover, the injected conidia produced elongated secondary hyphae after haustorium formation. Injected conidia developed these infection structures at rates comparable to those of noninjected conidia. Under the same injection conditions, fluorescein-isothiocyanate-conjugated albumin was successfully introduced into the cytoplasm of conidia. These results suggest that microinjection is a potentially useful technique for investigating plant host/fungal parasite interactions.