Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 30, 2011
Publication Date: February 1, 2012
Citation: Nyczepir, A.P., Wood, B.W. 2012. Foliar nickel application can increase the incidence of peach tree short life and consequent peach tree mortality. HortScience. 47(2):224-227. Interpretive Summary: The ring nematode, Mesocriconema xenoplax, is associated with making peaches more susceptible to peach tree short life tree death (PTSL). Some micronutrients [e.g., nickel (Ni)] have been shown to be beneficial in combating plant diseases caused by fungi, bacteria, or nematodes. Evaluating whether Ni foliar application can suppress ring nematode populations, thereby prolonging tree survival on a PTSL site is warranted. A long-term field study was initiated to determine the effect foliar Ni applications would have on ring nematode populations thus prolonging tree survival on a site having a history of PTSL. Results indicate that PTSL tree mortality was increased in Ni treated plots as compared to the untreated control and fumigated treatment plots. These data provide useful insights into foliar Ni application in peach that enhanced PTSL tree mortality and which may be useful in defining the mode of action responsible for tree death in this disease complex.
Technical Abstract: The ability of postplant nickel (Ni) foliar application to suppress Mesocriconema xenoplax populations and thereby prolong tree survival of peach trees on a peach tree short life (PTSL) site was investigated from 2004-2011. The study was conducted in an orchard infested with M. xenoplax and a history of PTSL. Plots consisted of three treatments: i) Ni [foliar applied]; ii) methyl bromide fumigation (MBr); and iii) an untreated control. Peach trees were planted into all plots in Mar. 2005 and the foliar Ni treatment was applied three times in 2005 and 2006. Nickel did not detectably suppress M. xenoplax populations as compared to MBr fumigation. The efficacy of MBr fumigation, as measured by M. xenoplax population density, collapsed 27 months after orchard establishment. Trees receiving multiple foliar Ni applications at 0.45 g.L-1 over two years, while exposed to M. xenoplax, exhibited greater PTSL mortality than trees growing in untreated or MBr fumigated plots. Thus, treatment of peach trees on a PTSL site with foliar Ni can deleteriously disrupt tree metabolic/physiological processes sufficient to increase incidence of PTSL tree mortality and should be used with caution in commercial orchards.