EFFECTS OF SOIL-MOISTURE, TEMPERATURE AND NUTRIENT AVAILABILITY ON THE POPULATION-DYNAMICS OF MUCOR PIRIFORMIS

The effects of soil moisture, temperature, and nutrient availability o n the population dynamics of Mucor piriformis?is were studied using mo isture levels from -0.1 to -40 kPa, temperatures from -1 to 25 degrees C, and three nutrient levels adjusted with pear juice. All three fact ors affected the population dynamics of M. piriformis in soil. Few int eractions occurred among the factors, and no interactions were observe d consistently. Populations of M. piriformis were higher in soil at -0 .1 kPa than in drier soils. Propagule density was highest in soil at 5 and 10 degrees during the first 30 d of the study but greater at -1 a nd 50 during the last 30 d. Propagule density consistently increased a s soil nutrient concentration increased. Results are discussed in rela tion to dynamics of M. piriformis in pear orchard soils.