RESUMEN
Banana bunchy top virus is a multicomponent circular ssDNA virus (family Nanoviridae) that causes one of the most devastating diseases of cultivated bananas and plantains (family Musaceae). It is transmitted by the aphids Pentalonia nigronervosa and P. caladii among host plants of Musaceae and some other families of monocots. Our Illumina sequencing reconstruction of virome components of BBTV-infected banana plants and their neighbor non-banana plants sampled in Vietnam and Laos revealed the monocot Commelina sp. (Commelinaceae) and the dicots Bidens pilosa and Chromolaena odorata (both Asteraceae) as hosts of BBTV and circular ssDNA alphasatellites (family Alphasatellitidae). Counting the proportions and relative abundances of Illumina reads representing BBTV genome components and alphasatellites suggested that Chromolaena and Commelina are poor hosts for BBTV and one to three alphasatellite species, whereas Bidens is a permissive host for BBTV and four alphasatellite species representing two genera of Alphasatellitidae. Our findings provide evidence for the dicot plants of family Asteraceae as alternative hosts of BBTV and its alphasatellites, which warrants further investigation of these and other dicots as a potential refuge and source of BBTV and multiple alphasatellites that become associated with this virus and likely affect its replication, transmission, and host range.
RESUMEN
A new species of Gesneriaceae, Didymocarpus phuquocensis, is described and illustrated from Phu Quoc National Park, Kien Giang Province, South-western Vietnam. It is most similar to D. pulcher, D. hookeri and D. punduanus in having 3-verticillate petiolate leaves, morphologically similar calyx, corolla, stamens, pistil and fruit, but differs from all in the glandular-pubescent stems, petioles and leaf blades, 1(-2)-flowered cymes, longer corolla and fruit and longer and densely glandular-puberulent ovary. Data on distribution, ecology, phenology and provisional conservation assessment of the new species are given along with an illustration and a colour plate.
RESUMEN
A new species of Theaceae, Camellia puhoatensis N.S. Lý, V.D. Luong, T.H. Le, D.H. Nguyen & N.D. Do, sp. nov., is described and illustrated from Nghe An Province, North Central Coastal Region, Vietnam. It is most similar to C. chrysanthoides, C. flavida and C. petelotii within sect. Archecamellia in shape and colouration of leaf, petal, ovary and glabrous stamen, but differs by its young puberulous shoot, mature leaf sparsely puberulous abaxially and leaf base rounded or broadly obtuse, petiole and pedicel puberulous, tepals 12-13, ovary and style pubescent. The comparison between the new species and C. velutina and C. dormoyana is presented. Data on distribution, ecology, phenology, use and provisional conservation assessment of the new species are given along with an illustration and a colour plate.
RESUMEN
Loxostigma puhoatense N.D. Do et al., sp. nov., a new species of Gesneriaceae, is described and illustrated from Pu Hoat Nature Reserve, Nghe An Province, Vietnam. This species is morphologically similar to L. dongxingensis and L. damingshanensis in the plant habit, indumentum system of vegetative and reproductive characters, shape of leaf blades, calyx, pistil but differs from the latter two by the abaxially reddish-purple leaf blade with pubescent along veins, lateral veins 11-19, shorter white to pale yellowish-white corolla (3.7-3.8 cm long) with purple-spotted and glabrous inside, longer abaxial stamens in 2-2.1 cm, shorter and densely glandular-puberulent ovary in 1-1.2 cm, and sparsely glandular-puberulent style. Data on distribution, ecology, phenology, and vernacular of the new species are provided.