- 作者: Ker-Chung Kuo
- 中文摘要: A two-step method was established to study the conidial germination and appressorium development in the mango anthracnose fungus Colletotrichum gloeosporioides during a 9-hour period. At first, mango decoction was added as supplemental nutrients into the spore suspension in order to trigger germination, and this was followed by depletion of the mango decoction to induce the formation of appressorium. This method could result in a high percentage of germination and appressorium formation in a uniform manner. Germinaton of C. gleosporioides took place within 2 hrs after conidia settled on the silanized cover glass. The total time span for germination and appressorium formation was 6- 9 hours. The first sign of conidial germination was the secretion of the extracellular matrix (ECM), which could be visualized with a hydrophobic, negative charged gold sol, Protogold, at about 20-30 minutes before germination. The ECM could be traced throughout the whole process of conidial germination and appressorium formation. In total, seven steps could be identified in the development of the appressorium: (1) ECM secretion, (2) nuclear division, (3) first septum formation, (4) germling emergence, (5) tip swelling, (6) 2nd septum formation and (7) melanization of the appressorium. Along with appressorium development, two rounds of mitosis could be visualized with a DNA specific fluorochrome, DAPI. The first round took place at the beginning of germination, and the second round occurred during the tip swelling stage of the germ tube. In most cases, only one nucleus could be seen inside the appressorium before it heavily melanized but, on rare occasions, 2-5 nuclei could also be found.
- 英文摘要: --
- 中文關鍵字: Colletotrichum gloeosporioides, mango anthracnose, germination, appressorium formation, extracellular matrix, nuclear behavior
- 英文關鍵字: --