Fall Performance and Post-dormancy Growth of `Midiron' Bermudagrass in Response to Nitrogen, Iron, and Benzyladenine

Field research was conducted to determine the effects of N, Fe, and benzyladenine (BA) on fall performance, post-dormancy recovery, and storage nonstructural carbohydrate composition of `Midiron' bermudagrass [Cy - nodon dactylon (L.) Pers.]. Fall green color retention and turf quality were superior for 48 than for 24 kg N/ha per month. Nitrogen level did not affect post-dormancy recovery or nonstructural carbohydrate levels in stolons and rhizomes measured in Sept. and Nov. 1983 and 1984. Iron level did not influence turf color and quality during summer months. Biweekly application of 0.6 kg Fe/ha produced better retention of greenness and turf quality during Fall 1983 and 1984 and superior turf color in Spring 1985 than the 0 kg Fe/ha treatment. Better green turf coverage was obtained with the biweekly than the monthly Fe (1.2 kg-ha-l) treatment during Fall 1983. In contrast, monthly Fe produced color and turf quality similar to that of the biweekly Fe treatment during Fall 1984. Nonstructural carbohydrates were similar among Fe levels in 1983 and 1984. The effects of Fe on turf color and quality were similar at each level of N and BA. BA level did not consistently influence turf color or quality and did not affect storage carbohydrate levels. When used in conjunction with moderate summer N fertilization, foliar-applied Fe can extend bermudagrass quality during fall without adversely affecting postdormancy recovery. Chemical name used: N- (phenylmethyl)-lH-purin-6-amine (benzyladenine, BA).