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Abstract

The seasonal development of testate amoebae and ciliates was studied in two peatbogs with different pH values. The values of numbers of testate amoebae were seasonally changeable. The highest numbers of testate amoebae were found in spring and summer with the dominance of Areclla vulgaris, Nebela barbata and Cucurbitella sp. The density during the autumn was the lowest. The highest numbers of ciliate communities were noted in spring and autumn during the mass development of small Scuticociliatida and Colpodea. The density throughout the summer was the lowest. Generally, in the present studies the abundance of testate amoebae was correlated with the abundance of bacteria and heterotrophic flagellates. The density of bacterivorous Colpodea, Scuticociliatida and Cyrtophorida correlated positively with the density and biomass of bacteria. In low pH peatbog relations between microbial loop components were stronger.
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Abstract

Our cytomorphological study of various populations of Elsholtzia ciliata (Lamiaceae) collected from high-altitude sites of Kashmir Himalaya revealed two euploid cytomorphotypes, diploid (n=8) and tetraploid (n=16), growing sympatrically but inhabiting two different habitats. This is the first report of tetraploid (4×) E. ciliata from the Indian subcontinent. We found the course of meiois to be normal in diploids, but tetraploid individuals showed chromosome and meiotic irregularities: cytomixis at early prophase I, stickiness at metaphase I, and chromosome bridges at anaphase I. In tetraploids, 23 of the 26 pollen mother cells observed at metaphase I showed 0-6 quadrivalents, suggesting that the tetraploid is a segmental allopolyploid. Microsporogenesis was also abnormal in tetraploids, showing the formation of triads. All these anomalies are conducive to lower reproductive potential (40.70%) in tetraploids than in diploids (90.50%). Significant morphological differences between the two cytotypes are presented.
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