Progress 09/01/07 to 08/31/09
Outputs
OUTPUTS: Over two years at 4 sites, the use of no treatment, two biologically based control systems with four biological and chemical integrated systems and a single chemically based system, yield of all systems were statistically superior to the non treated P,0.05). The biological treatment system consisting of ground barley, Trichoderma (T-22 product) and BmJ (emergence + 12"") and the integrated system consisting of ground barley, azoxystrobin infurrow and BmJ integrated with chlorothalonil had higher yields when compared to the chemically intensive system consisting of fludioxanil + mancozeb seed treatment, azoxystrobin infurrow and chlorothalonil foliar at the P<0.1 level. Potato scab and Rhizoctonia canker control was equivalent for all treatments and was superior to the untreated control. The best treatments for control of these diseases were the chemically intensive system and the integrated system consisting of Muscodor albus plus, azoxystrobin infurrow and BmJ alternated with pyraclostrobin. Use of sterile ground barley at 200-400 Lb/A applied infurrow provided control of scab. On the cultivars, Russet Norkotah and Russet Burbank, 25% of untreated potato stems were infected with Verticilium dahliae compared to 14.3 % for the Muscodor albus 620 seed treatment (33 kg/ha) and 7.3% for the 400 kg/ha Muscodor albus 620 in furrow treatments. The combination Muscodor albus 620 seed treatment (33 kg/ha) plus azoxystrobin 0.15 kg/ha applied at 20 cm growth had 10.3 % of stems infected. Black dot was only controlled in the chemically intensive system and the integrated systems. In separate early blight trials BmJ alone was better than the untreated or the chlorothalonil program. 47 potato cultivars were evaluated for black dot resistance and resistance was identified based on reduced early dying, reduced stunting and colony forming units/g stem. Cultivars showing resistance to black dot showed no or very small responses to chemical black dot controls whereas cultivars identified as susceptible showed as much as 40% yield increases from the chemical black dot treeatment. On the cultivars, Russet Norkotah and Russet Burbank, 17.7% of untreated potato stems were infected with Colletotrichum coccodes compared to 15.7 % for the Muscodor albus 620 seed treatment (33 kg/ha) and 10.4% for the 400 kg/ha Muscodor albus 620 in furrow treatments in field trials. The combination Muscodor albus 620 seed treatment (33 kg/ha) plus azoxystrobin 0.15 kg/ha applied at 20 cm growth had 4.0 % of stems infected. All treatments reduced Black dot infection significantly from the untreated or barley carrier only controls.Field trials in Hermiston , OR and in greenhouse trials BmJ induced resistance (BmJ applied at emergence then on 14 day interval) reduced Potato Virus Y infection by 56 and 55% respectively. BmJ did not reduce Potato Virus X infection in greenhouse trials. Five grower twilight field meetings were done at these demonstration sites. In addition to the five twilight grower meetings, three Montana Potato Improvement Association Annual meetings, a 6 hours of intensive potato IPM training meeting was held. This meeting was attended by 38 of 45 seed growers. PARTICIPANTS: Barry Jacobsen was lead PI and Nina Zidack assisted in field experiments and extension education. Mary Burrows assited with PVY and PVX greenhouse virus work. Dr. Phil Hamm provided assitance in Hermiston field research. The Montana Potato Improvent Association assited in financing this work and help with twilight and extension outreach workshops.In addition to the five twilight grower meetings, three Montana Potato Improvement Association Annual meetings, a 6 hours of intensive potato IPM training meeting was held. This meeting was attended by 38 of 45 seed growers. The growers each received copies of the APS Press publications: Potato Health Management and the Potato Disease Compendium. No publications to date but publications are in preparartion on the integrated management regiems and the black dot cultivar resistance. Reports with data have been provided to the Montana Potato Improvement Association at annual meetings in 2007, 2008 and 2009. The High PLains IPM site has been updated for these potato diseases. TARGET AUDIENCES: Montana Potato growers PROJECT MODIFICATIONS: The PVY field trial data is for 2009 only since trials in 2007 and 2008 had very low infection rates, although numerically BmJ reduced PVY infection by 3% in 2008. A 2010 trial is currently running at Hermiston, OR.
Impacts
This research and demonstration project has clearly demonstrated that fungicide use can be reduced without sacrificing either yield or control of scab, Rhizxoctonia canker, black dot or PVY. The new control for PVY by using BmJ induced resistance is very exciting and represents a totally new control concept.Virus control by BmJ or other inducer of plant resistance could potentially reduce the use of insecticides by potato seeed producers. The identification of black dot resistance may allow growers to more selectively use chemical contrtols for black dot and may encourage potato breeders to include black dot reistance as an objective. Poato growers are more aware of non-chemical alternatives and are more aware of losses due to black dot
Publications
- No publications reported this period
|
Progress 09/01/07 to 08/31/08
Outputs
OUTPUTS: In three repeated experiments using the cultivar Norkotah, induction of resistance with Bacillus mycoides isolate J (BmJ)5 days before inoculation prevented infection with PVY 42% of the time over 45 days post inoculation compaared to check plants induced with either dead BmJ cells or water. In comparison no control was noted in PVX experiments. When Bacillus mojaviensis isolate 203-7 (203-7) was used no control was noted for either virus. An interesting observation was that 203-7 induced plants demonstrated infections earlier than non induced plants, typically reaching 100% infection as measured by ELISA 5-10 days faster for both PVY and PVX. Induction at the time of inoculation was not effective for either PVY or PVX. Field trials at Hermiston,OR under natural infection conditions have been inconclusive due to very low virus infection although numerically BmJ plants treated 4 times at 14 day intervals has 6% less PVY infection 30 days after emergence and 4% less infection 60 days after emergence in 2008. Aphid transmission trials are underway. In two years of field trials ( both in research plots and in on farm trials) comparing biological control with Muscodor albus (MA)seed treatment, Trichodermam hazianum applied infurow(T-22) and BmJ, with chemical control programs ( fludioxanil + mancozeb-Maxim MZ) seed treatments,azoxystrobin (Quadris) infurrow and Chlorothalonil (Bravo) foliar; with integrated programs- Maxim MZ + MA seed treatment, a 1/2 rate of azoxystrobin infurrow and BmJ + 1/2 rates of Bravo or pyraclostrobin (Headline) and untreated potatoes for control of scab, ealy blight, Black dot root rot and Rhizoctonia canker. No treatment increased yields compared to untreated controls. The integrated treatm,ents controlled scab and Rhizoctonia equal to the chemical treatment and statistically better than no treatment. In early blight trials integrated treatments were equal to chemical treatments and far superior to untreated controls as measured by AUDPC. In regard to Black dot root rot control the biological treatment was nearly equal to the chmical treament and again far superior to no treatment in 2007. No data was obtained in 2008 due to as severe defoliating hail storm in August. Grower field days were held and a Potato IPM Workshop was held in March 2009 with 38 or 45 MT seed growers present. PARTICIPANTS: Eva Grimme did part of this work as her Ph.D thesis. Reserach work was carried ou at Hermiston, OR with Phil Hamm and at the Montana Eastern Agricultural Research Center at Sidney, MT and in MT seed grower fields. This work was partially supported by the MT Potato Improvement Council TARGET AUDIENCES: This research and extension program was oriented at MT seed potato producers. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
MT potato seed growers have adopted research showing control of scab, Rhizoctonia, black dot root rot and early blight. They have increased their funding for this research and have uniformly judged that the integrated control programs identified work. They will adopt these practices when MA and BmJ become commercially available
Publications
- Grimme, E. 2008. Mycofumigation with Muscodor albus: Effects on Verticillium wilt and black dot root rot of potato, Effects on Glomus intraradices and ectomycorrhizal fungi and M. albus proliferation in soil. Ph.D Thesis, Montana State University, 148 pages.
- Jacobsen, B. J., J. Eckhoff, J. Bergman and J. Staricka. 2007. 2007 Nesson Valley Potato Fungicide Trial. MSU Eastern Agricultural Research Center/ NDSU Willston Research-Extension Center 2007 Agricultural Research Update p.35
- Jacobsen, B.J. Effect of fungicide treatments on red Norland Potato Yields and severity of early blight at Nesson valley in 2008. MSU Eastern Agricultural Research Center-2008 Agricultural Research Update 14:44
|
|