Basella alba is a perennial plant of the Basellaceae, native to India, and is distributed widely in the tropics as an ornamental. It is also known as Indian spinach, Ceylon spinach, vine spinach, Malabar spinach or Malabar nightshade and is mostly cultivated as a leafy vegetable or spinach substitute, being rich in vitamin A and C. From 2008 to 2010, severe foliar disease was observed on B. alba in the region of Southern Andhra Pradesh, India. Approximately 75 to 85% of the fields were affected with disease incidence ranging from 70 to 90%. Leaf lesions were elliptical to irregular oval, yellow brown to dark brown, and sometimes concentrically zonate with diffuse margins frequently surrounded by light-colored haloes. Infection often started at the leaf tips and progressed to the base of leaves as symptoms developed. In severe infections, lesions enlarged and coalesced, causing necrosis, wilting, and ultimately death of leaves. Tissues from the margin of infected leaf parts were surface sterilized in 1% sodium hypochlorite for 1 min, plated on potato dextrose agar (PDA), and then incubated at 27°C in the dark for 7 days. Hyphal tips from the margin of each developing colony were subcultured on PDA. Fungal colonies were initially white, becoming olivaceous, and turning brown with age. Conidiophores were brown, short, simple, or sometimes branched. Conidia were obclavate, obpyriform or ellipsoidal with a short conical beak, borne in long chains, branched or unbranched, pale brown to brown, and 18 to 32 μm long and 5 to 14 μm wide at the broadest point. Conidia had three to eight transverse septa and one to two longitudinal septa. On the basis of conidial morphological characteristics, the pathogen was identified as Alternaria alternata (Fr.) Keissler (2). For pathogenicity tests, inoculations were performed on detached, surface sterilized, healthy leaves following the method of Belisario (1). A 5-μl drop of conidial suspension containing 1 × 105 CFU/ml was placed on each leaf and 12 leaves per isolate were used. Leaves were incubated in a growth chamber (90% relative humidity with a 12-h photoperiod). After 7 days, leaf spots that were similar to the original symptoms developed on all inoculated leaves and A. alternata was consistently reisolated from symptomatic leaf tissues on PDA. Control leaves inoculated with sterile distilled water remained asymptomatic. The experiment was performed three times. To our knowledge, this is the first report of A. alternata on B. alba in India. References: (1) A. Belisario et al. Plant Dis. 83:696, 1999. (2) E. G. Simmons. Alternaria: An Identification Manual. The American Phytopathological Society, St. Paul, MN, 2007.

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A novel actinomycete strain, designated VRC21(T), was isolated from the rhizosphere of Callistemon citrinus collected from Hyderabad, India. The morphological and chemotaxonomic properties of strain VRC21(T) was consistent with the characteristics of members of the genus Streptosporangium, that is, the formation of sporangia on aerial mycelium, coiled unbranched hyphae within the spore vesicle, the presence of meso-diaminopimelic acid in the cell wall, and madurose and galactose as major whole-cell sugars. Diagnostic polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol-mannosides. The predominant menaquinones were MK-9(H2) and MK-9(H4). The major cellular fatty acids were iso-C14:0, iso-C16:0, C17:0 10-methyl, C18:1w9c and C18:0 10-methyl. 16S rRNA gene sequence analyses revealed that strain VRC21(T) was a member of the genus Streptosporangium. The highest similarity values were observed with S. carneum DSM 44125(T) (98.2%) and S. fragile DSM 43847(T) (98.2%); the values of the remaining type strains were below 98%. The values of DNA-DNA relatedness between the strain VRC21(T) and the type strains of the related species were below 70%. On the basis of the polyphasic evidence, the strain VRC21(T) should be classified as novel species Streptosporangium terrae sp. nov. in the genus Streptosporangium. The type strain is VRC21(T) (=KCTC 29207(T)=MTCC 11724(T)).

Article Information A rot disease was observed on onion bulbs in major growing areas of Kadapa and Kurnool districts of Andhra Pradesh, India during 2010 to 2012. Based on pathogenicity, morphology and ribosomal DNA spacer sequences, the pathogen was identified as Fusarium proliferatum (Matsushima) Nirenberg. The fungus was isolated from onion bulbs presenting purple and reddish lesions, obtaining F. proliferatum consistently. The fungus produced effuse white colonies, branched hyphae, short conidiophores, slightly curved macroconidia, and single celled microconidia measuring 5.6-10.5 X 2.0-3.5 μm in diameter. Morphological identification of the fungus was confirmed using ribosomal DNA sequence data. Kotch's postulates were confirmed by performing pathogenicity test on healthy onion bulbs. This is the first report of F. proliferatum causing rot disease on onion bulbs in India; although it had already been reported for onion in the USA and Serbia.