Characterization ofArmillariaisolates from tea (Camellia sinensis) in Kenya

Abstract

Abstract:Armillaria is a primary root rot pathogen of tea (Camellia sinensis) in Kenya. The main species presently described in this country are A. mellea and A. heimii. A survey covering fourteen districts of Kenya was carried out and forty-seven isolates of Armillaria collected. Cultural morphology, rhizomorph characteristics, somatic incompatibility and features of basidiomata were used to characterize the isolates, together with molecular analysis based on randomly amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR), restriction fragment length polymorphism (RFLP) of the internal transcribed spacer (ITS) and the intergenic spacer (IGS) regions and sequence of the IGS region. It can be concluded that two Armillaria species were present and they were different from A. mellea. The first group was morphologically similar to A. heimii but this was contradicted by the molecular data, suggesting that A. heimii could be a complex of several species. The second group was different from the first and morphological and molecular data strongly suggest that it could be a new Armillaria species.

Identification of Armillaria nabsnona in Gastrodia Tubers

“…13,14) Methods based on molecular techniques are nowadays routinely used and provided a new perspective for phylogenetic and taxonomic studies.…”

“…11,12) Furthermore, mating pairings require fresh haploid cultures that sometimes are not available and a long period is required to obtain results. 13,14) Methods based on molecular techniques are nowadays routinely used and provided a new perspective for phylogenetic and taxonomic studies. 12,[15][16][17] PCR-RFLP analysis profiles of intergenic spacer 1 (IGS-1) have been successfully applied to the Armillaria species identification.…”

“…12,[15][16][17] PCR-RFLP analysis profiles of intergenic spacer 1 (IGS-1) have been successfully applied to the Armillaria species identification. 12,13,18,19) Sequencing of the internal transcribed spacer (ITS) and intergenic spacer 1 (IGS-1) regions 14,20,21) has also been used for identification. The ITS and IGS sequences available in the GenBank and the development of efficient software have provided a valuable tool for differentiation as well as for the detection of polymorphism and heterogeneity among species.…”

A reliable in vitro fruiting system for Armillaria mellea for evaluation of Agrobacterium tumefaciens transformation vectors

“…A requirement for a temperature reduction to induce primordia has been reported previously in Armillaria, in an undescribed species from Africa, where cultures colonised at 25 C required a temperature decrease to 20 C to initiate primordia development (Otieno et al 2003). Fruiting in other Armillaria species, however, does not appear to be reliant upon a temperature reduction, or perhaps the higher colonisation temperature prior to movement into cooler growth rooms provides a sufficient temperature decrease.…”

Identification of Armillaria species in Japan using PCR-RFLP analysis of rDNA intergenic spacer region and comparisons of Armillaria species in the world

“…Only one isolate of the type H was found in Tottori Prefecture. The A. mellea type G pattern corresponded to the pattern of A. mellea isolates from Kenya and São Thomé in the Gulf of Guinea (Otieno et al 2003). However, the Alu I digestion pattern of A. mellea isolates from Japan were different from those of European and North American A. mellea isolates (Harrington and Wingfield 1995;Kim et al 2000;Schulze and Bahnweg 1998).…”