Full TGIF Record # 23882
Item 1 of 1
Web URL(s):http://www.newss.org/proceedings/proceedings_1992_vol46.pdf#page=19
    Last checked: 07/24/2013
    Requires: PDF Reader
    Notes: Item is within a single large file
Publication Type:
i
Report
Content Type:Abstract or Summary only
Author(s):Webber, N. D.; Nelson, E. B.; Neal, J. C.
Author Affiliation:Cornell University--Graduate Student; Asst. Professor; Assoc. Professor
Title:Biological control of annual bluegrass (Poa annua var. reptans) with Xanthomonas campestris pv. poannua
Source:Proceedings of the 46th Annual Meeting of the Northeastern Weed Science Society. Vol. 46, 1992, p. 19-20.
Publishing Information:Ithaca, NY: Northeastern Weed Science Society
# of Pages:2
Keywords:TIC Keywords: Biological control; Poa annua; Poa annua var. reptans; Xanthomonas campestris
Geographic Terms:New York
Abstract/Contents:"In New York, annual bluegrass (Poa annua L.) is one of the most wide-spread and difficult-to-control weeds of highly maintained turf. The bacterium, Xanthomonas campestris pathovar poannua, is a facultative parasite isolated by Michigan State University researchers from diseased Poa annua in a golf course turf. Preliminary experiments have shown this bacterium to be pathogenic on annual bluegrass, to have a very narrow host range, and to require a wound (mowing) for infection. To further understand the interaction between annual bluegrass and X c. pv. poannua, our research was designed to determine the efficacy of Xanthomonas campestris pv. poannua on the perennial biotype of annual bluegrass, Poa annua var. reptans, under controlled (growth chamber) and field conditions. For all growth chamber tests, approximately 4-wk old annual bluegrass plants with 2- to 5-tillers were used. To evaluate the effect of wounding on pathogenicity, bacterial suspensions were sprayed or drenched on the foliage before or after clipping. Clipping heights were maintained at about 2.5 cm. Cells were applied at the rate of 1.0 ml of 10[superscript]9 cfu/ml suspension per 10-cm-diameter pot. The growth chamber was maintained at a constant 27 degrees C with a 12 hr photoperiod. The experimental design was a randomized complete block with three replications. Pathogenicity was determined by visual estimation of percent reductions of living tissue. In field tests, Poa annua var. reptans was seeded with native New York Poa annua seed 7 wk prior to inoculation. A mixed sod, composed of creeping bentgrass (Agrostis palustris) and annual bluegrass was transplanted to the test area approximately 11 wk prior to inoculation. Application rates were 750 ml each of 3.3 x 10[superscript]9 ,10[superscript]9, 3.3 x 10[superscript]8, 3.3 x 10[superscript]7, 3.3 x 10[superscript]6 cfu/ml suspensions, applied to 4.2 m2 plots. Treatments were applied three times at 2 wk intervals beginning 25 July 1991. Bacterial treatments were compared to an untreated control and an antibiotic treatment (Agri-Strep at 11.36 g/m2). Plots were mowed at 6.5 mm following treatment. The experimental design was a randomized complete block with four replications. Pathogenicity was evaluated visually a sin when plants were drenched or sprayed before cutting, compared to applications after cutting (Figure 1). Drench treatments were slightly superior to spray applications. However, by 50 days after treatment (DAT), all treatments provided 100% control. In field tests, control of annual bluegrass ws less satisfactory than in growth chamber tests. At 42 DAT, the maximum control obtained was about 18%. By 56 DAT, the annual bluegrass had begun a gradual recovery. These results deimonstrate that multiple applications may be necessary and timing of applications may be critical for satisfactory control of annual bluegrass. Xanthomonas campestris pv. poannua was pathogenic on Poa annua var. reptans. From these results it can be concluded that under growth chamber conditions, annual bluegrass can be effectively controlled with this bacterium. These data also demonstrate the need for continued research under field conditions."
Language:English
References:0
See Also:Other items relating to: POA
Note:Graph
This item is an abstract only!
ASA/CSSA/SSSA Citation (Crop Science-Like - may be incomplete):
Webber, N. D., E. B. Nelson, and J. C. Neal. 1992. Biological control of annual bluegrass (Poa annua var. reptans) with Xanthomonas campestris pv. poannua. Proc. Annu. Meet. Northeast. Weed Sci. Soc. 46:p. 19-20.
Fastlink to access this record outside TGIF: https://tic.msu.edu/tgif/flink?recno=23882
If there are problems with this record, send us feedback about record 23882.
Choices for finding the above item:
Web URL(s):
http://www.newss.org/proceedings/proceedings_1992_vol46.pdf#page=19
    Last checked: 07/24/2013
    Requires: PDF Reader
    Notes: Item is within a single large file
Find Item @ MSU
MSU catalog number: SB 610 .N62
Find from within TIC:
   Digitally in TIC by file name: newss1992
Request through your local library's inter-library loan service (bring or send a copy of this TGIF record)