VIEW ARTICLE

Physiology and Biochemistry

Effect of Maize Dwarf Mosaic Virus Infection on Sweet Corn Pollen and Silk. M. A. Mikel, Graduate research assistant, Department of Plant Pathology, University of Illinois, Urbana 61801; C. J. D’Arcy(2), A. M. Rhodes(3), and R. E. Ford(4). (2)(4)Assistant professor, and professor and head, respectively, Department of Plant Pathology, University of Illinois, Urbana 61801; (3)Professor, Department of Horticulture, University of Illinois, Urbana 61801. Phytopathology 72:428-431. Accepted for publication 8 June 1981. Copyright 1982 The American Phytopathological Society. DOI: 10.1094/Phyto-72-428.

The effects of maize dwarf mosaic virus (MDMV) on pollen vigor and on silk receptivity were examined as possible causes of sterility observed on ears from MDMV-infected sweet corn plants. Pollen was collected from six Zea mays L. cultivars (Aztec, BiQueen, Cherokee, Seneca Scout, Sugar Loaf, and Wintergreen) of MDMV-infected and uninfected sweet corn and germinated on an artificial medium. Pollen germination and germ tube length in vitro were measured after 2 hr of incubation at 25 C. Germination in vitro for pollen from healthy and MDMV-infected plants was not significantly different in five of six cultivars. In four cultivars (Aztec, Cherokee, Seneca Scout, and Sugar Loaf), pollen from MDMV-infected plants had significantly shorter germ tubes in vitro than did pollen from uninfected plants. In vivo germ tube lengths were measured in silks of crosses made with MDMV-infected (V) and uninfected (H) plants of the cultivars Sugar Loaf and Wintergreen. Within each cultivar, germ tube lengths in the cross H(female) × H(male) were significantly longer than those in the crosses H(female) × V(male), V(female) × H(male), or V(female) × V(male). The presence of MDMV in the silks of infected Sugar Loaf and Wintergreen was established by infectivity tests. MDMV was not detected in pollen grains of Sugar Loaf or Wintergreen by either enzyme-linked immunosorbent or infectivity assays.