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Claviceps sorghi occurred on Heteropogon triticeus in Gulbarga, Karnataka, India. Its external sphacelial morphology on this species differed from that on sorghum in having long white sphacelial tips that protruded from spikelets or wound around awns. The tips were formed by parallel synnema‐like hyphae and were covered by a phialide layer that produced elongated macroconidia (7–18 μm) and rounded to oval microconidia (3–5 μm). Unlike the macroconidia, the microconidia failed to germinate. Plated macroconidia underwent secondary sporulation. The white sclerotial stroma consisted of parallel hyphae with cylindrical cells that later became rounded due to accumulation of reserve metabolites. Some of these cells differentiated into a sclerotial rind that accumulated a terracotta‐coloured pigment. RAPD patterns and the rDNA nucleotide sequence confirmed the identity of the species.

Efficiency of vertical cylinder spore trap and seven day volumetric Burkard spore trap in monitoring airborne pollen and fungal spores.

Sorghum ergot is a serious disease that has caused major losses in sorghum growing regions worldwide. Claviceps africana, originally reported from Zimbabwe, is now the most widely distributed species causing ergot in many countries including the United States of America, whereas both C. africana and Claviceps sorghi exist in India. A third species (Claviceps sorghicola) has been described causing sorghum ergot in Japan. As the three species show morphological similarities, a DNAbased assay is desirable for rapid identification in cases where ergot-infected sorghum is found by regulatory authorities. We designed PCR primers and probes from the intron 3 region of the b-tubulin gene (for C. africana and C. sorghi) and the intron 4 region of EF-1a (for C. sorghicola) and tested them by real-time PCR with purified DNA and ergot samples from the field and greenhouse. The primer and probe sets specifically amplified DNA from the respective species with a detection limit of c. 1 pg DNA. Genomic DNA from six other Claviceps species did not amplify in any of the three ergot species-specific assays. The assays we describe will provide useful tools for detecting sorghum ergot pathogens in seed and grain shipments and for determining which species are present in the samples, thereby aiding in the regulatory decisionmaking process.