Abstract
ABSTRACT Some seed-borne fungi can survive in barley seeds; nevertheless, their survival period is unknown in barley seeds under storage conditions in Brazil. The aim of this study was to quantify the viability of the fungi Alternaria alternata, Bipolaris sorokiniana and Drechslera teres in barley seeds stored for 315 days during the off-season in the south region of Brazil. Each cultivar had 400 seeds disinfested and subjected to seed health testing in potato-dextrose-agar (PDA) from December 2011 to September 2012 at 35-day intervals. Data on fungal incidence and viability as a function of the storage time underwent regression analysis. All three fungi were detected in the five cultivars in all evaluated periods, and their incidence and viability significantly reduced with increasing storage periods. Monthly average reduction in the viability of A. alternata was 8%, while that of B. sorokiniana and D. teres was 10%. At the end of the off-season, viability of A. alternata, B. sorokiniana and D. teres, considering the average of cultivars, remained 49.8, 29.6 and 31.0%, respectively.
Highlights
Alguns fungos fitogênicos sobrevivem nas sementes de cevada, no entanto, o seu período de sobrevivência é desconhecido em condições de armazenamento de sementes cevada no Brasil
O objetivo do trabalho foi quantificar a viabilidade dos fungos Alternaria alternata, Bipolaris sorokiniana e Drechslera teres em sementes de cevada, armazenadas por 315 dias durante o período da entressafra na Região Sul do Brasil
ExpAerimental design was completely randomized with sub-samples of 25 seeds per sterile acrylic box, which were sown in PDA+A and incubated in a Biochemical Oxygen Demand (BOD), totaling 16 technical replicates randomly distributed inside the BOD
Summary
Alguns fungos fitogênicos sobrevivem nas sementes de cevada, no entanto, o seu período de sobrevivência é desconhecido em condições de armazenamento de sementes cevada no Brasil. Barley is predominantly cultivated in the southern Brazilian states of Rio Grande do Sul and Paraná and relies on treated seeds planted under a no-till system with crop rotation [17, 25]. Despite these management strategies, necrotrophic fungi can be found on aerial plant parts, which can lead to foliar disease epidemics and reduced yield [2]. The two most important barley foliar diseases in southern Brazil are brown spot and spot blotch, caused by B. sorokiniana and D. teres, respectively [20] These fungi can infect and grow in roots, coleoptiles or plumules, producing foliar spots and root diseases [20]. Within-plant transmission of A. alternata has not been studied yet
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have