Location: Crops Pathology and Genetics Research2010 Annual Report
1a. Objectives (from AD-416)
1. Develop, test, and demonstrate optimized integrated pest management (IPM) strategies for management of almond replant problem in Merced County without methyl bromide (MB). 2) Contribute to educational outreach to foster grower utilization of program findings in Merced County.
1b. Approach (from AD-416)
1. In collaboration with G. Browne, B. Lampinen, and S. Upadhyaya, an almond replant trial (almond to be replanted after removal of old almond trees) will be conducted in Merced County at a commercial field site with sandy soil and a history of ring nematode infestation. 2. In collaboration with Browne, treatments designed to evaluate efficacy of fumigant alternatives to MB will be applied to replicate mainplots-- 8- to 11-ft-wide strips of the land centered over future tree rows (strip treatments) or to 5 ft x 6ft rectangles of land centered over future tree planting sites (a spot treatment). The strip treatments will include a non-fumigated control, a fumigated control (MB, 400 lb/treated acre), Telone II (340 lb/treated acre), Telone C35 (540 lb/treated acre). The spot treatment will include Telone C35 (540 lb/treated acre, equivalent to approximately 54 lb/orchard acre). All of the treatments will be applied in fall 2009, and selected fumigant treatments will be tested with and without preceding summer-long rotations with sudan grass (in the absence of sudan grass rotations, the ground will be cultivated or sprayed periodically to maintain it relatively free from weeds). 3. At least two treatments designed to evaluate efficacy of non-fumigant alternatives to MB will be applied to 5 x 6 ft subplots centered over future tree planting sites and within the main plots. The subplot treatments may include treatments with steam and Brassica seed meal, steam, Trichoderma formulations, and fungicide and oomycete treatments. 4. Tree trunk diameters, visual disease severity ratings, and nematode samples will be collected at least two times per year. 5. Educational outreach will be achieved via a UCCE/ARS-hosted field demonstrations day at the trial site in Madera County. Documents Specific Cooperative Agreement with UCCE Merced County.
3. Progress Report
Agreement was established in support of Obj.1 of in-house project-the goal being to demonstrate alternatives to MB in key crop systems & regions dependent upon MB. The goal of this project is to develop, test, and demonstrate optimized IPM strategies for management of almond replant problems in Merced Co. without the use of MB. A site, in an area free of fumigant buffer zone restriction, for an almond replant trial was located in Merced Co. at a commercial field site with sandy soil and a history of ring nematode infestation. Fumigant treatments were applied and were designed to evaluate efficacy of alternative fumigants to MB and fumigant alternatives. The trial included a main plot testing soil fumigants, a 2nd plot testing fumigant alternatives, and a sudan grass cover crop trial. Within the main plot, treatments were applied to full rows of the cultivar ‘Nonpareil’ and were either a 8- to 11-ft-wide strips of the land centered over future tree rows(strip treatments)or to 5 ft x 6ft rectangles of land centered over future tree planting sites(a spot treatment). The strip treatments included a non-fumigated control, a fumigated control(MB, 400 lb/treated acre), Telone II(340 lb/treated acre), and Telone C35(540 lb/treated acre). The spot treatment included Telone C35(540 lb/treated acre, equivalent to approximately 54 lb/orchard acre). There were 4 whole row replicate plots containing 36 trees/treatment in a randomized block design. The 2nd experiment was established within the rows of the cultivar ‘Sonora.’ Spot treatments of steam, brassica seed meal(BSM), and a combination of BSM & steam were compared to C35 strip treatment. Alternative treatments were applied as spot treatments to the tree planting hole, using a 30” dia custom designed auger. The auger was placed over the center of the tree site and provided delivery of the treatment, either steam or liquid suspension, to a 24” depth. Distribution of the product was throughout the planting hole due to the mixing action of the auger and the ability for the auger to keep the treated soil within the treatment site. The C35 fumigant was applied using the row strip treatment described previously. Each treatment block consisted of 6 replicate trees. There were 12 total treated blocks. The steam treatment heated the soil to over 200F and maintained a soil temperature of over 150F for at least 6 hours post treatment within the treated area. For the BSM treatments, 3 trees within each block were treated with either 0.29 lbs/tree site(4000 lbs/treated acre) or 0.58 pounds/tree site(8000 lbs/treated acre), totaling 6 trees. For the combined BSM & steam treatment, BSM was applied at 0.29 pounds/tree site prior to application of the steam treatment. A 3rd trial was initiated to determine if a sudan grass cover crop rotation could increase tree growth within trial conditions. Whole row treatments consisted of either fallow ground or a 16' wide strip of planted sudan centered over the future tree row. The ADODR monitors this SCA by maintaining a complete file of the agreement, reviewing the annual reports, and conducting meetings with the cooperator during the course of the agreement.