Effects of Megafol and Calcium Metalosate® Applications at Early Bloom on April 2003 Planted DPL555BR Cotton

• Main Authors: Rethwisch, Michael D., Reay, Mark, Cox, Tim, Grudovich, Jessica, Wellman, Jessica, Hawpe, Erica
• Other Authors: Tronstad, Russell
• Language: en_US
• Published: College of Agriculture, University of Arizona (Tucson, AZ) 2004
• Subjects: Agriculture > Arizona; Cotton > Arizona; Crop management and physiology
• Online Access: http://hdl.handle.net/10150/198127

Foliar fertilizers are not widely used for cotton production in the low desert, and data about their effects on cotton production under these conditions is therefore limited. This study documented the effects of Calcium Metalosate7 and Megafol, each applied at the rate of 1 qt/acre to DPL555BR cotton. Treatments were applied on July 7, and plants had been growing vigorously just prior to application. Plots were approximately 0.75 acres in size with four replications. Plant mapping data from late July indicated that non-treated cotton had numerically higher retention rates at each of the first three fruiting positions mapped in addition to slightly more total nodes and a greater number of reproductive nodes in part due to first fruiting structure being retained lower on the plant (node 6.75) than treated cotton (node 7.95 for Megafol, node 8.4 for Calcium Metalosate7). Tractor passage through treated plots may have also knocked off developing squares however. No statistical differences were noted for lbs. of lint/acre, although treated cotton did have slightly higher yields than the untreated check (1,162 lbs/acre) and treatments were almost identical (1,203 lbs./acre for Megafol; 1,198 lbs./acre for Calcium Metalosate7). Fiber lengths and strengths were significantly different by treatment, with shortest and weakest fibers resulting from cotton treated with Megafol. Cotton from Calcium Metalosate7 treatments were significantly longer and stronger than lint from Megafol treated cotton plots, but lint from untreated cotton plots was significantly longer and stronger than either treatment (36.6 staple, 31.0 g/tex). The reasons for these differences are unclear. It is difficult to correlate the slight yield increases noted with treatments in early July, especially in light of lower retention rates noted with treatments from plant mapping data in late July and the large amount of lint production that occurred in late 2003 due to summer heat. Multiple differences were noted for treatments in regards to lint quality, however, indicating treatments did affect cotton production. Size of bolls and cotton lint from these early summer bolls was not obtained but may have been an overlooked aspect of this study.