Evaluation of Sampling Strategies for Determining Incidence of Cranberry Fruit Rot and Fruit Rot Fungi

Abstract

Two sampling strategies were compared and sources of variability in the sampling protocols analyzed to optimize sampling methods for studies of cranberry fruit rot that occurs in the field (i.e., field rot). For the first method, fruit were dry picked by hand from randomly assigned quadrats; for the second method, fruit were scooped from harvest floodwaters. Rot incidence, which ranged from 1.8 to 9.7%, did not differ significantly between upland and lowland sites or, in general, between dry-picked and wet-harvested samples. There were no consistent differences between upland and lowland sites in the frequency of isolation of any fungus from either rotten or sound fruit. The incidence of certain saprophytic and soilborne fungi was greater in wet-harvested compared with dry-picked fruit. In general, rot incidence and incidence of various fungal taxa isolated from fruit varied more among samples within sites than among sites. Site type (i.e., upland or lowland) was never a major source of variability. These findings suggest that if the goal were to assess the occurrence of cranberry fruit rot within a region, intensive within-site sampling would be necessary, but site type would not be an important consideration, at least in Wisconsin, where this study was conducted.

Breeding Trait Priorities of the Cranberry Industry in the United States and Canada

“…In Massachusetts and New Jersey, producers need to apply broad-spectrum fungicides four to six times per year to nearly all cranberry acreage (Oudemans et al, 1998). In Wisconsin, Oregon, Washington, and southern Canada, where the incidence of the disease is low, fungicides are needed only in specific areas or years (McManus et al, 2003). Because of the near-zero tolerance for fruit rot in the SDC market, losses associated with this disease are due to the rejection or downgrading of affected fruit loads (Nolte, 2015).…”

A Photographic Diagnostic Guide for Identification of the Principal Cranberry Fruit Rot Pathogens

“…As many as 15 fungal species contribute to the cranberry fruit rot disease complex (9,10,11), although the most significant economic losses can be attributed to a subset of five to seven species, depending on geographic region. Although rotten cranberry fruit take on various symptoms (Fig.…”

Lielogu dzērveņu ogu puves un to ierosinātāji Latvijā

“…Ražas laikā visbiežāk infekcija notiek caur ievainojumiem, tāpēc ierobežošana ar fungicīdiem nav iespējama, lai samazinātu puves izplatību uzglabāšanas laikā. Tomēr dažām sēnēm latentais periods var būt ļoti garš, pat vairākus mēnešusinficēšanās var notikt ziedēšanas laikā, bet labvēlīgiem apstākļiem iestājoties, puves pazīmes var parādīties tikai uzglabāšanas laikā (Oudemans et.al., 1998;McManus et al, 2003;Olatinwo et al, 2004;Sandler, 2008).…”

“…Uzglabāšanas laikā Physalospora vaccinii izplatīta neatkarīgi no novākšanas metodes. Savukārt C. empetri, Allantophomopsis cytisporea un A. lycopodina izplatīti vairāk vietās, kur ogas tiek novāktas ar uzplūdināšanas metodi un reti sastopami, kur ogas lasītas ar rokām (McManus et al, 2003).…”

“…2007. gadā varēja novērot vairākas sugas, tomēr to izplatība pēdējos gados ievērojami samazinājās. Latvijā lielogu dzērveņu stādījumos galvenokārt ir izplatīti divi patogēni -F. putrefaciens un C. empetri, kas ir dominējošās sugas lielogu dzērveņu audzēšanas reģionos ASV un Kanādā apvidos ar mērenu klimatu (Gourley, 1979;Olatinwo et al, 2004;McManus et al, 2003).…”