Evaluation of Twin-Line Cotton Production in Arizona - 2002

Twin-line (two seed lines 7.25 in apart per bed) and conventional single seed line per bed cotton production systems were compared at 16 sites across Arizona and Blythe, Ca. in 2002. The twin-line system produced more lint than the conventional single-line system at 4 of 16 locations; the yields of the twinline and single-line systems were 1273 and 1186 lb/acre, 1572 and 1461 lb/acre, 1478 and 1290 lb/acre, and 1309 and 1210 lb/acre, respectively, at the Grasty, Ramona, Rovey, and Wells sites, respectively. There were no significant differences in yield or fiber micronaire in 7 of the 16 experiments. The twin-line system produced less lint than the conventional system at 5 of 16 locations; yields of the twin-line and single-line systems were 2019 and 2189 lb/acre, 1400 and 1489 lb/acre, 1537 and 1845 lb/acre, 1065 and 1200 lb/acre, and 1271 and 1431 lb/acre, respectively, at the Chaffin (75K), Cooley, Hull, Papago, and Wakimoto sites, respectively. Fiber micronaire was reduced in five experiments; the micronaire values were 4.25 and 4.73, 4.46 and 4.78, 4.60 and 4.85, 4.76 and 4.98, and 4.93 and 5.15, in the twin-line and single-line systems, respectively, at the Rogers, Papago, Grasty, Hull, and Perry sites, respectively. Research will continue in 2003 in order to develop system comparison data for multiple years and to elucidate the reasons for the variable results measured in the 2002 cotton season.