Rough lemon seedlings were root dip-inoculated in Fries liquid cultures of two Fusarium solani isolates, one from California and one from Florida. Plants were potted and placed in soil temperature tanks at 15, 21, 27, and 33 C. Plant height, trunk diameter, and fresh weight of inoculated plants significantly differed from the control at 15 and 21 C. Plant height was the only growth parameter significantly affected by inoculation at 27 and 33 C. Height of plants inoculated with the California isolate was significantly less than the control at 27 but not at 33 C. Height of plants inoculated with the Florida isolate did not differ from the controls at 27 and 33 C. Significantly more root rot occurred on inoculated plants at 15 and 21 C, but not at 27 and 33 C.