This study was conducted at the JV farms at Gila Valley. Lettuce variety ‘Guapo’ was seeded, then sprinkler-irrigated to germinate seed on September 19, 2023, on double rows 12 in. apart on beds with 42 in. between bed centers.  Rest of the irrigation was supplied by furrow irrigation or rainfall. Treatments were replicated five times in a randomized complete block design. Each replicate plot consisted of 25 ft of bed, which contained two 25 ft rows of lettuce. Plants were thinned on October 9, 2023 at the 3-4 leaf stage to a 12-inch spacing. Treatment beds were separated by single nontreated beds. Treatments were applied by incorporating in soil before seeding or with a tractor-mounted boom sprayer that delivered 50 gal/acre at 100 psi to flat-fan nozzles spaced 12 in apart.

 
Fusarium wilt (caused by Fusarium oxysporum f. sp. lactucae ) rating was done in the field by observing the typical symptom of lettuce wilt. Confirmation was done by cutting the cross section of roots. Disease scoring/rating was done on December 6, 2023. 
 
The data in the table illustrate the degree of disease control obtained by application of the various treatments in this trial. The disease pressure was extremely high in 2023, and most treatments showed little or no control against the disease. The treatments that showed some activity were Bexfond, Cevya, Rhyme, and Serifel. Plant vigor was normal and phytotoxicity symptoms were not observed in any treatments in this trial.

The University of Arizona in Yuma offers degree programs in Agricultural Systems Management and Crop Production. These programs are conducted cooperatively with Northern Arizona University and Arizona Western College. These programs are housed at the Arizona Western College campus and include classes in pest management, crop production, business management, agricultural law and other subjects. Classes are offered primarily in the evening to accommodate students who have full or part time jobs.

While fundamental academics are important, many of the classes offered in Yuma include practical, hands-on experience that is more difficult to acquire on the campus in Tucson. The Applied Weed Science Class, PLS 300, that is currently being taught puts emphasis on the practical aspects of weed science that will be helpful to pest control advisors, farm managers and others involved in field and vegetable crop production in the low deserts.

This course includes segments in general weed science, chemical and non-chemical weed control. The 14 students enrolled in the spring semester of this course are currently presenting written and oral reports on a weed species they have chosen that is common in this area. We hope to include many of the presentation in these advisories. The one that is included today is presented by Ryan McGuire, about a weed, southern brass buttons, that has become increasingly widespread in La Paz County where Ryan works as a pest control advisor with the Wilbur Ellis Company. Please click on the picture to watch video.