A Loop-Mediated Isothermal Amplification (LAMP) Assay for Rapid and Specific Detection of Airborne Inoculum of Uromyces betae (Sugar Beet Rust)

Sugar beet rust disease (causal agent Uromyces betae) represents a serious threat to worldwide sugar beet (Beta vulgaris) crops, causing yield losses of up to 10% in the United Kingdom. Currently, the disease is managed mainly by application of fungicides after rust disease symptoms appear. Development of a future forecasting system, incorporating data on environmental factors and U. betae inoculum levels, would enable better disease control by more targeted application of fungicides. In this study, we developed a first molecular diagnostic, targeted to cytochrome b DNA sequences and based on loop-mediated isothermal amplification (LAMP) technology, for rapid (<30 min) and specific detection of U. betae. The new assay only detected U. betae strains (collected from across eastern England, the main sugar beet growing region in the United Kingdom) and Denmark; it did not detect other closely related pathogens (e.g., Puccinia sp., U. fabae) or others that are commonly found on sugar beet (Cercospora beticola, Erysiphe betae, Ramularia beticola). The assay could consistently detect down to small amounts of U. betae DNA (10 pg). Application of the new LAMP diagnostic to air spore tape samples collected between mid-June and mid-September from a single U.K. sugar beet field site revealed differences in temporal patterns of pathogen inoculum between the 2015 and 2016 seasons. The described LAMP assay could now be used as a component of a future automated inoculum-based forecasting system, enabling more targeted control of sugar beet rust disease.

Uromyces betae. [Distribution map].

A new distribution map is provided for Uromyces betae[Uromyces beticola] Kickx. Hosts: Beet (Beta). Information is given on the geographical distribution in AFRICA, Algeria, Egypt, Ethiopia, Kenya, Libya, Morocco, South Africa, Uganda, ASIA, Bangladesh, Iran, Israel, Lebanon, Turkey, USSR (Siberia), Yemen, Arab Republic, AUSTRALASIA & OCEANIA, Australia, New Zealand, EUROPE, Austria, Belgium, Britain & Northern Ireland (Jersey), (Guernsey), (Scilly Islands), Bulgaria, Cyprus, Czechoslovakia, Denmark, Finland, France, Germany, Greece, Hungary, Irish, Republic Italy (incl. Sicily), (Sardinia), Malta, Netherlands, Norway, Poland, Portugal (Azores), (Madeira), Romania, Spain, (Canary Islands), Sweden, Switzerland, USSR, (Latvia, Bashkir, Leningrad, Ukraine), (Lithuania), (Esthonia), Yugoslavia, NORTH AMERICA, Canada (British Columbia), USA, SOUTH AMERICA, Argentina, Bolivia, Chile, Uruguay.

Micromicetes españoles: Notula II

Se dan a conocer los resultados obtenidos del estudio sobre Micromicetes. Las especies que se reseñan son: Puccinia hieracii (Schum.) Mart.; sobre Hieracium auricula L.) = H. lactucella Wallr.; Puccinia simphyti-bromorum Muller. subsp. benekeniGdum, sobre Bromus racemosus L. Puccinia lapsanae Fuck., sobre Lapsana communis L.; Uromyces scilla rum(Gerv.) Wint., sobre Scilla vana L.; Uromyces betae (Pers.) Lev., sobre Beta vulgaris L. subsp. maritima (L.) Arcangeli.; y Puccinia umbilici Guep., sobre Coledon pendulinus DC = Umbilicus rupestris (Salisb.) Dandy.

Uromyces betae. [Descriptions of Fungi and Bacteria].

A description is provided for Uromyces betae[Uromyces beticola]. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On sugar beet, beetroot, spinach beet, mangolds and wild beet (Beta vulgaris subsp. vulgaris, B. vulgaris subsp. maritima), Beta vulgaris, B. cycla, B. rapa. DISEASES: Beet rust. First appears as small, cinnamon brown pustules scattered over the lamina, which in susceptible plants quickly spreads over the entire foliage causing the older leaves to wilt, wither and die prematurely. The younger leaves remain erect but their blades become crumpled drooping and yellowish. Badly rusted plants with blisters on leaf blades and petiole finally collapse. GEOGRAPHICAL DISTRIBUTION: Africa (Algeria, Canary Is., Libya, Madeira, Morocco, S. Africa); Asia (Israel, Iran, U.S.S.R.); Australasia (Australia, New Zealand, Tasmania); Europe (Austria, Belgium, Bulgaria, Channel Islands, Czechoslovakia, Cyprus, Denmark, Finland, France, Germany, Greece, Great Britain, Holland, Hungary, Ireland, Italy, Latvia, Malta, Norway, Poland, Portugal, Rumania, Sardinia, Spain, Sweden, Switzerland, Turkey, U.S.S.R., Yugoslavia); N. America (Canada, Mexico, U.S.A.); S. America (Argentina, Bolivia, Chile, Uruguay). (C.M.I. Map No. 265) TRANSMISSION: Mainly by urediospores (McKay, 1952, 44, 566a). Overwinters on seed crop stecklings, clamped mangolds, groundkeeping beet and mangolds. Spores adhering to seed clusters helps to spread the disease. Reports from U.S.S.R. indicate that teliospores retain viability for 2 yrs. in store houses.