The Significance of Plant Wounds in Effective Control of Annual Bluegrass (Poa annua L. ) with Xanthomonas campestris pv. poae (JT-P482)

Abstract

In the use of the phytopathogenic bacteria Xanthomonas campestris pv. poae (JT-P482) as a bioherbicide to control annual bluegrass, a wound is necessary for the bacteria to enter the plant. In this paper, the relationship between wound treatments and efficacy is described. (1) The more wounds, especially in parts of the plant closer to the stem, the greater the efficacy obtained. Therefore, in putting greens, it is important to make annual bluegrass stand upright by using a thatchingreel mower or grooming techniques before mowing. (2) For efficient use, the interval between cutting and JT-P482 treatment should be as short as possible. In addition, if treatment is carried out under severe conditions (e. g. dryness) the cut & spray method is recommendable for practical use. (3) Changes in the bacterial numbers in annual bluegrass plants after repeated mowing (to a height of 1.5cm) were determined. Seven days after treatment, bacterial populations in plant tissue reached a maximum (10¹⁰ CFU/g FW)