GROWTH AND PROTEIN CONTENT IN COLLETOTRICHUM CIRCINANS, FUSARIUM SOLANI AND RHIZOCTONIA SOLANI IN LIQUID CULTURE

Authors: JUAREZ, M. - EAST CENTRAL UNIV. ADA,OK; JUAREZ, D. - EAST CENTRAL UNIV. ADA,OK; Russo, Vincent

Submitted to: Biologia Plantarum
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2000
Publication Date: N/A
Citation: N/A

Interpretive Summary: Both length of exposure to light and amount of air present, especially in the soil, can affect development of fungi. Species of three plant pathogenic fungi, i. e. Colletotrichum, Fusarium and Rhizoctonia were grown in culture for 72 h under different flow-rates of air, and length of exposure to air, in two media. In general, fungal dry weights increased a flow-rate of air and length of exposure to light increased. Protein bands from all fungi were formed on SDS-PAGE gels. The Fusarium species produced more protein bands, which had a broader range of weights, than for the other two fungi. This may suggest that Fusarium is more adaptable to culture conditions than the others. Also, conditions of culture need to be considered when interpreting protein profiles.

Technical Abstract: Fungal growth and metabolic processes are affected by culture conditions. Species of the phytopathogenic fungi Colletotrichum, Fusarium, and Rhizoctonia, were incubated for 72 h in Potato-Dextrose broth (PDB) or Czapex-Dox broth (CDB), and exposed to 0, 12, or 24 h/day of broad spectrum mfluorescent light while 0, 0.5, or 1 liter per minute (LPM) of air was bubbled through the media. In PDB, dry weights of Colletotrichum and Rhizoctonia increased linearly as exposure to light and air-flow-rate increased. In CDB, fungal dry weights were not affected by treatment. When incubated in either media, Fusarium dry weight fit quadratic functions. In PDB, Fusarium dry weight was greatest at 12 h of light or 0.5 LPM. In CDB, Fusarium dry weight was less at 0 h of light or 0 LPM than at 24 h of light or 1 LPM. The length of exposure to light and air-flow-rate air interaction affected protein concentration in fungi. For Colletotrichum in PDB, total protein produced under 0 h of light increased as air-flow-rate increased, but under 12 and 24 h of light protein concentration was higher at 0 than at 1 LPM. For Fusarium, concentration of protein decreased as air-flow increased only under 0 h light. For Rhizoctonia, at 12 and 24 h of light, protein concentration was highest at 0.5 LPM, but was not affected by 0 h of light. In CDB, only Rhizoctonia was affected by the interaction, with protein concentration being lower at 0 than at 1 LPM at all light exposures. Length of exposure to light and air-flow-rate affected number, and distribution, of protein bands in SDS- PAGE gels. Most protein bands were under 30 kD, and number of bands varied with air-flow-rate within a light exposure. For Fusarium in CDB,