Cotton lint yields in the variety trials in Graham county were higher than the 1987 yields by close to 200 pounds per acre. Two varieties, BR 110 and NK KNX 111 (now KC 311) yielded more than DP 90 at the Thatcher site, the highest yield being 1,569 pounds of lint per acre. In Eden, DP 90 was the highest yielding variety with 1,237 pounds of lint per acre. The New Mexico acalas didn't yield as much lint per acre as the top yielding varieties, but with 1988's premium, produced substantial income per acre. In Thatcher the highest yielding acala produced $861 per acre compared with BR 110's $910, whereas in Eden the highest yielding acala produced $736 per acre against DP 90's $717.

Nine acala varieties were grown in the Cochise area of Cochise county. An experimental New Mexico variety B510 was the top yielder in the test, producing 1,287 pounds of lint per acre. The top variety in 1987, 1517-77BR, was next to the bottom in the 1988 test, probably due to low plant population. Variety characteristics such as plant height, wilt susceptibility, relative maturity and lint turnout are quantified in the study along with final plant populations and lint quality. Information on cotton variety strip trials implemented in the county is also given.

Two short staple variety trials and 1 long staple variety trial were harvested in Greenlee county in 1988. In the short staple trial comparing the new and experimental New Mexico acalas with 2 other lower quality varieties, Genhains new GC 260 was the top yielding variety with 1,087 pounds of lint per acre, but it came in fifth when comparing dollar value per acre because of the premium structure for the New Mexico acalas. Two new experimental acalas, 2745 and B510, produced the highest income per acre. The short staple trial, which tested longer - season varieties, had problems with low micronaire values. The newly released 1517-88 variety produced the top yield and produced the most income per acre. Two of the experimental long staple varieties topped the yield of S-6 and 3 of the 7 varieties tested yielded over 650 pounds of lint per acre.

Seven upland cotton varieties and pima S-6 were demonstrated in Mohave Valley in Mohave County in 1988. The elevation there is 500 feet. Of the 7 upland varieties, 2 were new and had not previously been tried in the area; 1 had been tried for the first time last year. Pima S-6 was a new introduction to the Valley. Trial results indicated that the new introduction Tifcot 56 led the trial, yielding 901 lbs. of lint per acre. It was followed by DPL 90 at 886, DPL 50 at 884, DPL 77 at 819, BR 110 at 76$ DES 119 at 755, and Delcott 344 at 664. The first attempt at pima S-6 yielded 447 pounds of lint per acre. Its plot in 1988 was basically new ground that had not had a crop on it for the past 5 years.

A short staple variety trial was conducted on the demonstration farm, at the Maricopa Agricultural Center in 1989. Twenty varieties, received from various seed companies, were entered into the test. Results from the analysis showed significant differences among varieties with no observable performance trend in terms of maturity types (long or short season). The lint yields in this test ranged from 4679 to 3353 lbs. acre⁻¹ for DPL90, and S55 respectively.

Seven cotton varieties including Pima S -6 were demonstrated in Mohave Valley, Mohave County in 1989. Of the six upland varieties two were new varieties not previously demonstrated in this area. Trial results indicated DP77 at 1697 lbs. led other varieties by 109 lbs. of lint over DP90, 1590 lbs. and 287 lbs. over bottom variety STV115 at 1412 lbs. STV110 yielded 1482 lbs., DES 119 at 1429 lbs., DP50 at 1414 lbs. Pima S-6 yielded 950 lbs. The two new varieties STV110 and STV115 placed last and third on yield but when economic values were calculated based on grade and price they ranked third and fourth. The second attempt on Pima saw an increase in yield from 447 lbs., the previous year to 950 lbs. in current trial.

The old standar4 1517-75, was the best yielding variety in 1989, yielding over three bales of lintper acre. 1517-77BR, which yielded well in 1987 and then dropped off a bit in 1988, carne in second and an experimental, 6658 came in third. The touted New Mexico star, 1517-88 came in fourth followed closely by California's Prema. Eight of the 10 varieties tested yielded over 2.5 bales per acre. More than normal heat units coupled with good management practices brought the highest yields yet recorded in a University cotton variety trial in Cochise County.

Forty-nine, short- staple varieties and Pima S -6 were grown in a replicated trial on the Safford Agricultural Center in Graham County. Most of the varieties were commercially available in the Cotton Belt, however, a few experimental varieties from the New Mexico acalas and from Delta Pines were included. Weather conditions were favorable through most of the year and the cotton produced well. Fifteen varieties produced more than 4000 pounds of seed cotton per acre, with the highest yielding variety producing 4759 pounds per acre. Delta Pine 77 was the highest yielding commercial variety but it was topped by an experimental New Mexico acala.

Short- staple variety trials were grown in two locations in Graham County in 1989. Exceptional weather conditions, coupled with good management practices, provided record cotton yields in the Safford valley. Delta Pine 77 was the highest yielding variety in the Thatcher location with a yield of 1740 pounds of lint per acre. An experimental acala from New Mexico came in second in this triad ahead of Delta Pine 90. Delta Pine 90 was the highest yielding variety in the Eden area with a yield of 1196 pounds per acre. Data on percent first pick plant height and plant populations are presented for each variety in each location. Graphs of heat units received each day throughout the growing season at the AZMET station on the Safford Agricultural Center are presented for 1988 and 1989.

Two short staple and one long staple variety trials were implemented in Greenlee County in 1989, with new varieties topping each trial. The most exciting new discovery was HS 46, which topped the competition in the short-staple trial by nearly 200 pounds of lint per acre. In the acala trial, the top four entries were composed of three New Mexico experimentals and Prema from the San Joaquin Valley. Any one of these acalas could become the new standard for the valley. P-69 in the long staple cotton trial yielded over 850 pounds of lint per acre and topped the S-6 yield by 25%. The testing program in Greenlee County is not only of benefit to the cotton producers and related agri-businesses in southeastern Arizona, but also to southwestern New Mexico.