Ten short staple cotton varieties including two New Mexico acalas varieties and one advanced strain, four California acalas and three Australian upland varieties were tested in the 1996 variety study. The Australian variety IF 1001 had the highest lint yield with a yield of 1013 pounds per acre, followed by the New Mexico advances strain. The average yield was more than 100 pounds per acre lower than the previous year, due to an early frost. In addition to lint yields; percent lint, plant heights, height to node ratios, plant populations and lint hvi values are shown. A lint yield comparison for 1993 through 1996 is included in this paper.

Thirty four short staple varieties were grown in a replicated field trial on the Safford Agricultural Center. Due to a replant in late May, the results are viewed as a late-plant situation. DP 35B was the highest yielding variety with a yield of 1353 pounds of lint per acre with DP 90 in second place but with 80 pounds of lint less per acre. Agronomic values for the plants at harvest and HVI data for lint quality are tabulated in this paper.

Variety trials were grown at two locations and with two different sets of short staple varieties. One trial on the Robbs farm, north of Kansas Settlement, tested seven acalas varieties from New Mexico and California and one variety from Australia. The other trial on the Noel Curry farm, near the town of Cochise, tested nine upland varieties as part of the statewide testing program and three acalas from NM and CA. The highest yielding variety in our tests was SG 125 with a yield over 3 bales per acre. In the acala study, the Australian variety and an experimental from NM were the highest yielding varieties with yields just over 2 bales per acre. Lint quality of each variety and an estimated crop value are also given in this paper.

TWO on farm, replicated short staple variety demonstrations were established in 1996. Twelve varieties were evaluated on the Carpenter farm in Solomon and on the Colvin farm in Eden. Several new varieties were planted in both studies, including 2 varieties from Stoneville, 2 varieties from Australia and DP 35B, the Bt version of DP 5690. Delta Pine 5690 and DP 35B were the highest yielding varieties with yields of 1697 and 1220 pounds of lint per acre at the Solomon and Eden locations, respectively.

Twenty five upland cotton varieties were grown at the Maricopa Agricultural Center as part of the national cotton variety testing program. Lint yield, boll size, lint percent, plant population, plant height and fiber property data are presented in this report.

Upland cotton advanced strains and commercial check comparison varieties were evaluated in replicated field studies at four locations in 2000. The test sites include Yuma, AZ., Buckeye, AZ., Maricopa, AZ., and Safford, AZ.. Nine seed companies submitted a maximum of five advanced strains entries per location. Three commercial check varieties were used at each site for comparison purposes and included DP 5415, SG 125, and STV 474.

Each year the University of Arizona conducts variety trials across the state to evaluate the performance of upland cotton varieties. These tests provide unbiased data on the performance of varieties when tested side-by-side under typical production practices. In 2000, we planted a total of ten trials, one in the southwestern region (Yuma county), six in the central region (MoHave, La Paz, Maricopa, and Pinal counties), one in the southern region (Pima county), and two in the eastern region (Graham and Cochise counties). We tested six to ten commercially available varieties in each test. The purpose of this report is to present the results of our 2000 tests conducted in southwestern, central and southern Arizona. Lee Clark presents results from eastern Arizona in two companion reports in this publication. The results show that many varieties performed well at several locations, indicating good adaptation to Arizona conditions. The highest yielding varieties did not always produce the most value per acre, clearly demonstrating the importance of both yield and fiber quality in determining the value of the crop. Growers should carefully weigh the costs and benefits of yield, quality, and transgenic technology when selecting varieties.

One replicated on-farm short staple variety trial was planted in Graham County in 2000. Ten varieties were evaluated on the Larson farm in Thatcher. Several new varieties were planted in these studies, including 5 transgenic varieties, 3 varieties from Buttonwillow Research in California, and the newest acala from New Mexico. The Australian variety, FiberMax 989, produced the highest yield with 895 pounds of lint per acre. Paymaster 1560 BRR and DPL 655BRR followed close behind and were not separable statistically from the leader. Yield and other agronomic data are reported by variety along with HVI values from the lint.

Twelve varieties were tested including three New Mexico Acalas and one Acala from Buttonwillow Research in California, three roundup Ready varieties, a buctril resistant variety, a Bollgard variety and three other varieties. The highest yielding variety in the trial was 1517-99, with FiberMax 989, 1517-95 and SureGrow 521RR following in yield. Yields were considerably lower than seen in the previous year’s study (1). Several Roundup Ready varieties were included in this study. Plant mapping data and HVI data are also included in this report.

Eighteen Acala cotton varieties were tested in a replicated small plot trial on the Safford Agricultural Center in Graham county at an elevation of 2950 feet. The highest yielding variety in this study was Hazera 195-208, an interspecific hybrid from Israel, with a yield of 1387 pounds of lint per acre. It was followed closely by two varieties from New Mexico, 1517-99 and B7514. Hazera 195-208 had the highest yield in an interspecific hybrid study and 1517-99 was the highest yielding Acala variety in the Upland cotton regional variety trial in 1999 (1). The next five varieties consisted of two interspecific hybrids from Israel, a variety from Buttonwillow Research and two advanced strains from New Mexico. Yield and other agronomic data as well as fiber quality data are contained in this paper.