VIEW ARTICLE

Cytology and Histology

Nuclear Behavior and Division in Germinating Conidia of Botrytis cinerea. N. Shirane, Aburahi Laboratories, Shionogi Research Laboratories, Shionogi & Co., Ltd., Koka-cho, Shiga 520-34, Japan; M. Masuko, and Y. Hayashi. Aburahi Laboratories, Shionogi Research Laboratories, Shionogi & Co., Ltd., Koka-cho, Shiga 520-34, Japan. Phytopathology 78:1627-1630. Accepted for publication 12 May 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/Phyto-78-1627.

Light-microscopic observations were carried out on resting and dividing nuclei in germlings of Botrytis cinerea incubated in potato-dextrose broth at, 22 C in darkness. The conidia contained various numbers of nuclei, commonly up to 10. Nuclei in each cell were divided synchronously by mitosis. The time elapse between the initiation of nuclear division and septum formation was approximately 2 hr. The cell cycle of the fungus was about 2.7 hr. Nuclei appeared to migrate through the septal pore and aggregated in the area of the appressorium. The growing tips of many germlings collapsed after treatment with methanol-acetic acid solution, releasing chromosomes at metaphase. The number of chromosomes counted in many burst germlings was 16. The length of each chromosome at metaphase ranged from 0.6 to 1.3 μm and the width was 0.2 0.3 μm; total length of the component was 13.1 μm. One of the chromosomes had an additional threadlike structure.