%0 Journal Article %J Canadian Journal of Botany %D 1990 %T Differential responses of C3 and C4 grasses to mycorrhizal symbiosis, phosphorus fertilization, and soil microorganisms %A Hetrick, B.A.D. %A G.T. Wilson %A Todd, T.C. %K tallgrass prairie %X

The responses of five C4, warm-season and five C3, cool-season tallgrass prairie grasses to phosphorus (P) fertilization, mycorrhizae, and soil microorganisms were compared in greenhouse studies. The warm-season grasses responded positively to mycorrhizae and to P fertilization, but mycorrhizal plants did not respond to P. The soil microflora reduced mycorrhizal plant dry weight and root colonization. In contrast, cool-season grasses did not respond to mycorrhizae or P fertilization. Soil microorganisms did not suppress cool-season plant growth, but root colonization was reduced in nonsterile soil. For the warm-season grasses there was an inverse relationship between mycorrhizal root colonization and P fertilization and a positive relationship between root colonization and plant dry weight. For the cool-season grasses there was also an inverse relationship between root colonization and P fertilization, but the relationship between root colonization and plant dry weight was negative. In both the warm-season and cool-season grasses, low levels of mycorrhizal root colonization persisted even when P fertilization was sufficient to eliminate mycorrhizal effects on plant growth. Thus, warm-and cool-season grasses display profoundly different strategies for nutrient acquisition. Key words: cool-season grasses, warm-season grasses, vesicular-arbuscular mycorrhizae

%B Canadian Journal of Botany %V 68 %P 461 -467 %G eng %M KNZ00283 %R 10.1139/b90-061