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Spore balls of false smut of rice caused by Ustilagonoidea virens were collected from different major rice belts of eastern part of India. Ten isolates from ten different locations were collected and isolated in the laboratory for their, cultural, morphological and molecular characterization. Potato sucrose agar media was used for their cultural studies and observation on colony diameter, colour and sporulation were made. Spores of all the isolates were observed under scanning electron microscope (SEM) and light microscope for spore size, spine length and colour. Differences in colony characters were observed where the highest mycelial growth was observed in isolate Uv2 with 5.33 cm colony diameter and lowest mycelial growth was observed in Uv9 (3.70 cm). Most of the isolates produced white and circular colony. Spores of all the isolates observed under a light microscope appeared to be olive green in colour, however, a significant variation in spore size and spike length under SEM was observed. Spores size and spike length of different isolates ranged between 4.533 μm to 6.169 μm and 362.567 nm to 799.533 nm, respectively. For genetic identification and variability, DNAs of isolates were amplified using ITS1 and ITS 4 primers. The length of nucleotide sequences of different isolates varied from 583 to 606 bp. Phylogenetic analysis revealed genetic variation among the isolates, dividing them into two major groups. [ABSTRACT FROM AUTHOR]

The morphology and distribution of the trichomes on the aerial parts and the feature of moniliform hairs in the stamen of Pogostemon Desf. of Assam, India were studied to understand the significance of these characters for taxonomic purposes. The three species studied are Pogostemon brachystachyus Benth., Pogostemon quadrifolius (Benth.) F. Muell, and Pogostemon strigosus (Benth.) These species of Pogostemon Desf. were mostly terrestrial while few species growing in marshy areas also. The trichomes on leaves and the moniliform hairs or beaded stamen of all the three species were investigated by both Light microscope and Scanning Electron Microscopy (SEM). The stamen with hairs was considered a unique feature that makes it a distinct genus in the family Lamiaceae, and also helps in the identification. The main types of trichomes that were distinctively observed on the leaf surfaces are, simple non-glandular unicellular and multicellular trichomes and peltate, glandular trichomes. Moniliform hairs and trichome morphology of Pogostemon brachystachyus, Pogostemon quadrifolius, and Pogostemon strigosus have not been studied previously in the study area and such investigations on Pogostemon in the study area are rather limited. [ABSTRACT FROM AUTHOR]

Bakanae disease caused by Gibberella fujikuroi, Sawada, Wollenworth (teleomorph) (anamorph: Fusarium fujikuroi Nirenberg), is emerging as a serious disease of rice in India. Histopathological study of plant tissue during infection can provide valuable insight for understanding the pathogenesis and the mechanism of resistance. The early infection process of F. fujikuroi in rice was observed at microscopic level using light microscopes and scanning electron microscope (SEM). In seed, the pathogen was observed in the husk, embryo and endosperm with maximum colonization in the husk region. Different infectious structures such as swollen tip hyphae, infectious hyphae, appressorium and infection cushion were observed in F. fujikuroi-rice interactions. The estimates of per cent (%) transmission of inoculum (seed-seed; seedlings-seed and florets-seed) revealed maximum transmission of F. fujikuroi through florets followed by seedlings and seed. The present study established that the infection of rice plants by F. fujikuroi can occur through three routes namely seed, seedlings (soil) and florets (air). The information generated in the present study will be valuable for providing an understanding on the pathogenesis and help to device effective strategies for management of bakanae disease of rice. [ABSTRACT FROM AUTHOR]

The article focuses on the microscopic studies of wear patterns on the edges of tools using incident light microscopes and Scanning Electron Microscopes (SEM) coupled with Energy Dispersive Spectroscopy (EDS) have proved to be effective methods of determining stone tool function. It states that a pilot study was undertaken to examine the scope and application of use wear studies in an Indian Mesolithic context. It states that the site of Bagor, Rajasthan is one of the largest and best preserved middle Holocene sites in India, which were studied.