Variety And Insecticide Seed Treatment Performance In Mississippi

   In an effort to help rice producers make decisions for 2008, “Mississippi Variety Trial” data collected in 2006 and 2007 are summarized below.
   Averaged over 2006 and 2007, Clearfield XL729 has shown a 31% yield advantage over CL-161 and CL-171AR. For the same time period, no yield difference was detected between CL-161 and CL-171AR. Furthermore, CL-161 and CL-171AR produced similar yields at over 20 locations. Neither cultivar out-performed the other more than 3 to 4 bu/A. CL-161 did have an advantage to other Clearfield cultivars with respect to whole milled rice. Whole milled rice of CL-161 was 3.8% better than Clearfield XL729 and 0.6% better than CL-171AR. One disadvantage to Clearfield XL729 is that its average height was 5 inches greater than CL-161 and CL-171AR.
   Clearfield XL730 and Clearfield XP745 responded comparably to Clearfield XL729 in rough rice and whole milled rice yields; however, Clearfield XL730 has more shattering potential. Considerable yield losses were observed with Clearfield XL730 due to excessive winds from Hurricane Katrina in 2005. Plant height is a disadvantage for Clearfield XP745 as it averaged 2.5 inches taller than Clearfield XL729 and 8 inches taller than CL-161. As a result, the lodging potential with Clearfield XP745 is higher than Clearfield XL729, CL-161, or CL-171AR. In two strip trials comparing CL-161 and CL-171AR, CL-161 showed more susceptibility to lodging than CL-171AR.
   In comparisons of conventional cultivars, XL723 demonstrated a 14% yield advantage over Cocodrie and Wells. Whole milled rice for XL723 was 0.5% lower than Cocodrie, while Wells was 4.4% lower than Cocodrie. XL723 averaged 2 inches taller than Wells and 6 inches taller than Cocodrie. XL723 would fit well on lighter soil that has recently been land formed, as well as areas with greater blast potential.
   In one year of evaluations, XP744 produced equivalent rough rice and whole milled rice yields to XL723; however a disadvantage of XP744 compared with other cultivars is that it averaged 3 inches taller than XL723 and 9 inches taller than Cocodrie.
   In 2007, two trials were conducted to evaluate the use of Cruiser™, V-10170, and Dermacor™ X-100 as a seed treatment for the control of rice water weevil larvae. Each trial consisted of seed treatments of Cruiser™ at 2.05, 2.56, and 3.072 fl oz/100 lb seed, V-10170 at 2.56, 3.84, and 5.12 fl oz/100 lb seed, and Dermacor™ X-100 at 1.2, 2.4, 4.8, and 9.6 fl oz/100 lb seed. These seed treatments were compared to a foliar application treatment of Karate at 2.56 fl oz/A at 3 days following flood establishment and untreated check was also included, which received no seed treatment and foliar application.
   For each treatment replication, two-4 inch soil cores were extracted at 3 weeks following flood establishment. The most effective and consistent control of rice water weevil larvae was achieved with Cruiser™ at 3.072 fl oz/100 lb seed, V-10170 at 3.84, and 5.12 fl oz/100 lb seed, and Dermacor™ X-100 at 2.4, 4.8, and 9.6 fl oz/100 lb seed. Δ