Impact of Fungal Gummosis on Peach Trees

Abstract

<jats:p>Peach tree fungal gummosis caused by <jats:italic>Botryosphaeria dothidea</jats:italic> [(Moug.:Fr.) Cos &amp; de Not.] is widespread throughout the southeastern United States. Until recently, its economic impact on peach [<jats:italic>Prunus persica</jats:italic> (L.) Batsch] has been impossible to estimate, since no effective controls were known. Significant, though not total, suppression of gummosis on `Summergold' peach trees was achieved with an intensive 5-year spray program with captafol. Captan was far less effective than captafol. Both trunk diameter and fruit yield were negatively correlated with disease severity. After eight growing seasons, trees treated with captafol were 18% larger than the untreated trees. Yield of mature captafol-treated trees was 40% to 60% high er than that of untreated ones. Following termination of the spray program after 5 years, disease severity gradually increased on both captafol- and captan-treated trees. However, through eight growing seasons, disease severity was significantly lower on captafol-treated trees. This study demonstrates that peach tree fungal gummosis significantly depresses tree growth and fruit yield on susceptible peach cultivars.</jats:p>

Insights Into the Etiology of Gummosis Syndrome of Deciduous Fruit Trees in Israel and its Impact on Tree Productivity

“…Symptomatic trees exude large amounts of gum on the trunk, limbs, branches and twigs, accompanied by sunken lesions on the bark. At later stages, twigs, branches, shoots and limbs wilt and die (Beckman, Pusey et al 2003). At later stages, twigs, branches, shoots and limbs wilt and die (Beckman, Pusey et al 2003).…”

“…The effect of fungal gummosis syndrome of deciduous fruit trees on the yield is not well documented (Beckman, Pusey et al 2003). In the USA, it is considered as "a nuisance that can be pruned out of trees during the dormant season with no economic significance" (Beckman, Pusey et al 2003).…”

“…In China, Li et al (1995) reported that disease incidence in area around Zhejiang ranged from 46 to 100% and mentioned that the syndrome reduced fruit production. Attempts to cope with the gummosis syndrome reveled that frequent scraping of the lesions and painting of the exposed tissue with chemicals inhibit the pathogens in the trees and suppress the disease but their economic benefit was questionable (Li, Cao et al 1995;Beckman, Pusey et al 2003) In Israel, the fungal gummosis syndrome was studied by Sztejnberg and collogues during the late 1970's. Based on a countrywide survey, the main causal agent was identified as Hendersonula toruloidea Nattrass (Achilea and Sztejnberg 1976;Jakoby 1982;Rotem 1991).…”

Neofusicoccum parvum associated with fruit rot and shoot blight of peaches in Greece

“…In addition, this pathogen has been isolated from many other hosts, such as blueberry (Espinoza et al 2009), Syzygium cordatum ), avocado (McDonald et al 2009), grapevine (Laveau et al 2009), eucalyptus ), and walnut. Other species of Botryosphaeriaceae such as Botryosphaeria dothidea are associated with fruit rots and fungal gummosis of peach trees in many countries (Cedelo et al 1994;Combrink et al 1984;Caponero et al 1999Caponero et al , 2001Beckman et al 2003). Although N. parvum has been associated with serious problems of peach cultivation in other contries, there has been no investigation of the importance of this pathogen in Greece.…”

Phoma glomerata (Corda) Wollenw. & Hochapfel a new threat causing cankers on shoots of peach trees in Greece

“…A diffuse canker, often with a concentric appearance and exuding gum, can be found on the fruiting wood at the base of the blighted shoots. Fungi of the genus Monilinia, Phomopsis, Cytospora, Fusicoccum, and Colletotrichum have been reported as causes of shoot blights in peach orhards (Bernstein et al 1995;Uddin et al 1997;Luo and Michailides 2001;Beckman et al 2003;Pokharel and Larsen 2008). Species of genus Phoma, such as P. pomorun and P. fimeti, have been reported as pathogens causing "shot hole" in peach leaves, but no Phoma species has been found to infect peach shoots.…”