Parthenium weed (Parthenium hysterophorus, Asteraceae) is a common, invasive weed found throughout the Indian subcontinent, Africa, America and Australia. The observed disease, Parthenium Witches' Broom (PWB), characterised by phylloidy, stunting and prolific branching was observed during a field survey conducted between September 2014 to June 2015. PWB phytoplasma was detected in all symptomatic plant samples and in the previously reported insect vector, Orosius albicinctus belonging to family Cicadellidae (subfamily Deltocephalinae) and other Hemipteran insect samples by amplifying its 16S rRNA gene. To our knowledge, this is the first report of a 'Ca. Phytoplasma aurantifolia'-related strains associated with witches' broom disease of P. hysterophorus and insect vector Orosius albicinctus.

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Wild indigo (Tephrosia purpurea (L.) Pers.) grows as a common weed throughout the Indian subcontinent. The plant has pinnate leaves, white or purplish flowers, and flat hairy pods, and is cultivated as a green manure crop. The plant extracts contain compounds such as tephrosin, an aromatic ester, prenylated flavonoid, and sesquiterpene (2) that have medicinal properties. The newly recognized disease, Tephrosia purpurea witches' broom (TPWB), was characterized by chlorosis, stunting, and proliferative branching, which were suggestive of phytoplasma infection during a field survey conducted in November 2013. To determine the presence of phytoplasma, 2 g of compound leaves from three symptomatic and asymptomatic plants were used for total DNA extraction using the CTAB method. The phytoplasma 16S rRNA gene was detected in all three symptomatic plants using nested PCR with universal phytoplasma primer pairs, P1/P7 followed by R16F2n/R16R2 (4). No amplification was observed in DNA isolated from asymptomatic plants. PCR fragments (1,246 bp in length) generated from symptomatic T. purpurea plants were sequenced directly using five different primers viz. 343R, 536F, 704F, 907R, and 1103F. TPWB phytoplasma 16S rRNA gene sequence (GenBank Accession No. HG792252) showed 99.12% homology with a ‘Candidatus Phytoplasma aurantifolia’ strain WBDL (U15442) when compared using the EzTaxon 16S rRNA database (3). Virtual restriction fragment length polymorphism (RFLP) analysis was carried out on the obtained sequence using iPhyClassifier (5). The virtual RFLP pattern derived from the HG792252 sequence was different to the reference patterns of previously established 16Sr groups and subgroups. The reference pattern of the 16Sr group II, subgroup C (AJ293216) was most similar with a similarity coefficient of 0.92, which placed it in a new subgroup, 16Sr II-M (1). Furthermore, virtual RFLP results were confirmed by digesting R16F2n/R16R2 amplicon with BstUI, DraI, HinfI, HpaI, and MseI restriction enzymes according to manufacturer's instructions. To our knowledge, this is the first report of a ‘Ca. P. aurantifolia’-related strain associated with witches'-broom disease of T. purpurea in India. References: (1) H. Cai et al. Int. J. Syst. Evol. Microbiol. 58:1448, 2008. (2) A. K. Khalafalah et al. Pharmacognosy Res. 2:72, 2010. (3) O.-S. Kim et al. Int. J. Syst. Evol. Microbiol. 62:716, 2012. (4) C. Smart et al. Appl. Environ. Microbiol. 62:2988, 1996. (5) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

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Sequencing.Rumex acetosa L. (sorrel) belongs to family Polygonaceae. It is an indigenous English plant, common, too in the greater part of Europe, in almost all soils and situations. The medicinal action of sorrel is refrigerant and diuretic, febrile disorders and in scurvy. In India it is cultivated as a medicinal and vegetable throughout the year. Both the root and the seed were formerly esteemed for their astringent properties, and were employed to stem haemorrhage [1]. During October 2009 to January 2011 an extensive surveys was conducted in sorrel growing areas of Marathwada region of Maharashtra, India where diseased plants were found with yellow discoloration of the vascular tissue in stems, wilting of the lower leaves & root rot (Figure1). Roots from wilted plants were collected and cut into small pieces (2mm) and then surface sterilized with mercuric chloride (1% HgCl 2 ) for 1 min. The pieces were then washed with sterilized distilled water three times, blotted dry and plated on potato dextrose agar (PDA) medium and incubated at 27±2 o C in BOD incubator. On PDA medium, Fusarium species with catenate microconidia and macroconidia borne on polyphialides was consistently isolated from the infected roots. Pathogenicity tests were conducted, using six healthy sorrel plants grown in the glasshouse. Two plants and a control were used for each of two replications. For each treated plants were sprayed with 5 ml conidia suspension (ca.1×10 5 conidia/ml) in sterilized water (SDW) and maintained in a humid growth chamber for 24 h in room temperature. Five days after inoculation, white mycelial roots were infected and in control remained symptomless. The fungus was reisolated & was identical as Fusarium species. The fungal culture is deposited at CODON Life Sciences, Goa and Research laboratory, Department of Botany Arts, Science & Commerce College Naldurg Dist Osmanbad, Maharashtra State, India with Accession No.HQ332533.Thirty isolates were identified as Fusarium proliferatum (Matsushima) Nirenberg [2,3].Cultural colonies were started from single conidium and grown on PDA at 27±2 o C under fluorescent lights providing 12 hrs light period. The abundant aerial mycelium initially was white and later became purple violet. Colonies were fast growing, hyphae were septate and hyaline. Conidiophores were short, simple and branched. Microconidia were abundant and produced on mono and polyphialids, single celled, oval to club shaped size 7.0-22.5×3.5µm. Macroconidia were slightly sickle shaped to straight, with 2-5 septa and measured 43-65×3.3-5.0µm. Chlamydospores were absent (Figure 1).