THE GENUS PYTHIUM - An-Najah National University
THE GENUS PYTHIUM - An-Najah National University
THE GENUS PYTHIUM - An-Najah National University
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
<strong>PYTHIUM</strong> DISSOTOCUM Drechsler 1. Wash. Acac. Sci. 20:402 (930).<br />
COLONY MORPHOLOGY: Colonies on CMA forming a distinct<br />
chrysanthemum growth pattern; no development of aerial mycelium.<br />
MYCELIUM: Main hyphae 4-7 (av. 4.3),um wide. SPORANGIA: Filamentous,<br />
slightly inflated. Zoospores formed at IO-20°C. OOGONIA: Mostly terminal,<br />
sometimes intercalary, subglobose, smooth, 15-22 (av. 18.4 ± 0.7-95% ~.I.),um<br />
diam, occasionaly with papilla. AN<strong>THE</strong>RIDIA: 1-3/ oogonium. Mostly<br />
monoclinous commonly sessile arising from the oogonial stalk immediately<br />
below the oogonium, sometimes diclinous, antheridial stalks unbranched.<br />
OOSPORES:Aplerotic, 12.5-18 (av. 15.1 ± 0.5-95% c.I.)..um diam, wall 1-2.5<br />
(av. 1.4 ± 0.13-95% C.lJ .um thick. Ooplasts 6-12 (av. 8) .nm diam.<br />
TEMPERATURE-GROWTH RELATIONSHIPS:Minimum 5C, optimum 20-<br />
25 0 C, maximum 35 0 C. Daily growth rate on CMA at 25 0 C 11.4mm.<br />
MATERIAL EXAMINED:ex Lens culinaris Medik, Tubas (FCCAU 136.4);<br />
and ex soil, Nablus (FCCAU 136.1 & FCCAU 136.2).<br />
OCCURRENCE:Infrequently isolated from diseased roots, and rarely from<br />
soil (found in only one soil). This species was also recorded from soil in the<br />
Lebanon (Ahrens, 1971).<br />
3()
Change language