Fire Blight Disease Caused by <i>Erwinia amylovora</i> on <i>Rosaceae</i> Plants in Kyrgyzstan and Biological Agents to Control This Disease

Abstract

Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacterium E. amylovora were tested within in vitro and in vivo conditions. The results revealed the ability of Streptomyces antagonistic bacteria to decrease fire blight severity on pear and apple trees during the first stage of the fire blight disease in leaf tissues. Streptomyces strain C1-4 suppressed E. amylovora disease symptoms in the leaf tissues and excised apple and pear shoots. The incidence of fire blight on leaves was reduced by about 70% with two applications of bacterial antagonists. Further studies at different locations in Kyrgyzstan, using large scale application, would allow for stronger recommendations to be made, including studies and recommendations on their ability to prevent disease and to use them as main components in an integrated pest management program.

Genetic characterization of Erwinia amylovora isolates detected in the wild walnut-fruit forest of South Kyrgyzstan

“…Since its first appearance in Kyrgyzstan in 2008, fire blight has progressively expanded in several regions of the country (Doolotkeldieva and Bobushova 2016) 3), confirming the fact that Cydonia spp. are among the most susceptible hosts for fire blight (Postman and Stockwell 2009).…”

Fire Blight of Fruit Crops

“…To date, the disease has been identified in 50 countries around the world [1, 2]. Bacterial fire blight has also been identified in the countries of the former Soviet Union, including Russia, Belarus, Ukraine, Moldova, Latvia, Kazakhstan, and Kyrgyzstan [3,4]. On the territory of Kazakhstan, fire blight was first registered in the early 2000s, and its range is expanding from year to year.…”

“…К настоящему времени заболевание выявлено в 50 странах мира [1,2]. Бактериальный ожог обнаружен и в странах бывшего СССР, в том числе России, Белоруссии, Украине, Молдавии, Латвии, Казахстане, Киргизии [3,4]. На территории Казахстана бактериальный ожог был впервые зарегистрирован в начале 2000-х годов и его ареал из года в год расширяется.…”

In Vitro Approbation of Microbial Preparations to Shield Fruit Crops from Fire Blight: Physio-Biochemical Parameters

“…The success in biological control has spurred further research into potential bacterial and fungal biocontrol agents against various crop pests [ 15 , 16 ] and diseases [ 17 ]. Streptomyces C1-4, for example, have shown promise in reducing fire blight damage; specifically, strain notably decreased symptoms and reduced the incidence of fire blight on leaves by about 70% after two treatments [ 18 ]. In Egypt, spraying with non-pathogenic bacteria such as Bacillus subtilis , Pantoea agglomerans , and Harmel plant extract ( Peganum harmala L.) was effective in controlling fire blight [ 19 ].…”