The evaluation of infection caused by different fungi species of highbush blueberry plants grown on selected commercial plantations located in central Poland

W latach 2017–2018 prowadzono badania dotyczące wy-stępowania chorób powodowanych przez grzyby na czterech plantacjach borówki wysokiej zlo-kalizowanych w centralnej Polsce. Celem badańbyła izolacja i identyfikacja patogenów z pora-żonych organów krzewów borówki wysokiej. W badanym materiale roślinnym zidentyfikowano cztery gatunki grzybów. Na wszystkich lustrowa-nych plantacjach obserwowano Botrytis cinerea, Godronia cassandrae i Phomopsis vaccinii, a tyl-ko na jednej plantacji zidentyfikowano Valdensia heterodoxa. Grzyby identyfikowano na podstawie oznak etiologicznych obecnych na porażonych organach roślin, przy użyciu klasycznych metod. W ramach badań oceniono skuteczność siedmiu fungicydów w zwalczaniu choroby szara pleśńborówki wysokiej. Do badań wykorzystano za-równo preparaty powszechnie polecane w ochro-nie borówki wysokiej przed szarą pleśnią, jak i fungicydy dopuszczone do ochrony przed tą cho-robą upraw innych roślin jagodowych (truskawka i malina). Fungicydy Luna Experience 400 SC i Prolectus 50 WG mogą być rozważane jako uzu-pełnienie listy środków zalecanych do zwalczania choroby szara pleśń na plantacjach borówki wy-sokiej.

Studies Regarding the Combat of the Braches Burns Produced by the Phomopsis Vaccinii at Blueberry Bushes Cultivated in Maramures County

This study has examined the response of two species of the blueberry bushes: Elliot and Bluecrop cultivated in the climate conditions of the years 2014 and 2015 to the attack of the Phomopsis vaccinii; we have also testedand determined the biological efficiency of three fungicide products in order to recommend the best of them to be used in the bushes treatment. The attack was calculated by determining the disease frequency (F%) and its intensity (I%). We also calculated the biological efficiency for the three selected products, considered as being the best ones. We utilized the interrupted-linear setting method which consists of 5 plants/three repetitions / product and we monitored 3 plants from each repetition; 2 marginal plants were for untreated control. Our analysis of the two species pointed that the Bluecrop species has a much higher sensitivity against the pathogen than the one discovered in the Elliot species. The calculation of the biological efficiency proved that the best product Funguran OH 50 PW (90,5%) was followed by Alcupral 50 PU (88,8%) and the Copac ( 86,2%) for the Elliot variety, occupied the last place; the same hierarchy with smaller values was found for the Bluecrop variety.

Diaporthe vaccinii. [Distribution map].

A new distribution map is provided for Phomopsis vaccinii Shear. Sodariomycetes: Diaporthales: Diaporthaceae. Hosts: Vaccinium spp. Information is given on the geographical distribution in Europe (Germany, Latvia, Lithuania, Netherlands, Poland, Romania and UK), Asia (China, Shandong), North America (Canada, British Columbia, New Brunswick, Nova Scotia, Quebec, USA, Arkansas, Illinois, Indiana, Maine, Maryland, Massachusetts, Michigan, Montana, New Jersey, North Carolina, Oregon, Washington, West Virginia and Wisconsin) and South America (Chile).

Morphological Diversity of Phomopsis vaccinii Isolates from Cranberry (Vaccinium macrocarpon Ait.) in Latvia

Phomopsis vaccinii cause a serious disease of blueberry, cranberry and other Vaccinium crops in the North America and Europe as well. Over 1000 species names are described by Phomopsis spp., but their biology and life style are mostly unknown. Identification of P. vaccinii by methods of classical phytopathology is difficult and complicate, because many species are morphologically similar to P. vaccinii, and P. vaccinii itself has diverse patterns of colony morphology. For this investigation P. vaccinii isolates were obtained from five cranberry plantations in different locations of Latvia (Babite, Alsunga, Rucava, Ape and Pargauja municipality) from berries affected by viscid rot at harvest and storage in 2010. Altogether 44 P. vaccinii isolates were cultivated on potato dextrose agar for description of colony morphology. In order to find some relationships between samples, the isolates were arranged in different groups on the basis of mycelium color and structure (zoning), reverse pigmentation, pycnidium formation time, size, location, number and size of conidia. During this study the colonies of P. vaccinii from cranberry in Latvia showed different morphological features in culture and no relationships between growing regions and groups of isolates were found. P. vaccinii is easy to confuse with other Phomopsis species if only classical phytopathological methods are used.

Fungicide Efficacy and Specificity Toward Fungi in the Cranberry Fruit Rot Disease Complex

Cranberry fruit rot is an economically important disease complex comprised of as many as 15 different fungi that destroy cranberries in the field and/or after harvest. We evaluated fungicides in six field trials over 3 years for their ability to reduce the incidence of cranberry fruit rot and for their specificity in controlling six principal pathogens in the complex: Coleophoma empetri, Colletotrichum acutatum, Colletotrichum gloeosporioides, Phomopsis vaccinii, Phyllosticta vaccinii, and Physalospora vaccinii. Fruit rot incidence and efficacy of fungicides varied greatly among replicate plots within trials and among trials, often making it difficult to discern significant differences among treatments. However, in general, the newer strobilurin and sterol demethylation inhibitor (DMI) fungicides were at least as effective as the industry standards, chlorothalonil and mancozeb. An exception was the DMI fungicide fenbuconazole, which was ineffective in three of five trials. Compared to other fungicides, fenbuconazole was weak in controlling Colletotrichum gloeosporioides, which along with Coleophoma empetri, dominated among fungi isolated from rotten berries. The results are being used to develop disease management programs that control the key fruit rot pathogens with reduced reliance on environmentally risky and potentially carcinogenic fungicides. Accepted for publication 21 January 2014. Published 14 March 2014.