The 2009 ASHS Annual Conference

Brassica greens are an important commercial vegetable crop for producers within Oklahoma.   These crops are grown for both processing and for fresh market.  Trials were arranged in a randomized block design with four replications, each plot consisting of 4 rows on 12 inch row centers 20 feet long.  Seeding rates were approximately 435,600 seeds per acre.  Plots were direct seeded in fall of 2007 and spring of 2008 using a research cone planter.  Weed control included 0.5 lb ai/acre of Treflan (trifluralin) applied pre-plant incorporated and one hand weeding for both trials.  No other pest control efforts were necessary.  The studies received 130 to 150 lbs N/acre, respectively for spring and fall.  Nine cultivars were included in both trials.  White rust was observed in the fall trial, but no disease infections were observed in the spring study.  The spring trial was rated for bolting (flowering) at harvest and the fall trial was rated for disease (white rust).  Data recorded at harvest included overall plot yields.  Yields varied significantly as did bolting and disease severity.  In general, the authors felt that the most important aspect of the trials was the opportunity to observe these cultivars for bolting resistance in the spring.  There were significant differences observed between different cultivars with the Kales being the most bolt-resistant.  Highest yielding cultivars in spring the trial included Darkibor kale, Miike Giant Mustard, and Savannah mustard spinach.  Highest yielding cultivars in the fall trial included Summer Fest and Green Boy mustard spinach (Brassica rapa).