Male meiotic studies in ten species of grasses (Poaceae) were carried out from District Kinnaur, Himachal Pradesh, India, between the altitudinal ranges of 2000 to 3080 m. All the species were worked out cytologically for the first time from the study area. The hexaploid cytotype in Thysanolaena agrostis (n=33) made new addition for the species on a worldwide basis, supplementing the earlier report of n=11 and 12. The meiotic course in all the species studied was found to be abnormal. Cytomixis in two species, Apluda mutica and Elymus dahuricus was reported here for the first time. Besides abnormal meiotic course the microsporogenesis was found to be normal in all the species but these abnormalities results in the reduction of pollen fertility in the plants.

ABSTRACT. The present investigation involves the meiotic studies on two populations of Calamagrostis emodensis Griseb.(Family: Poaceae) from District Kinnaur, Himachal Pradesh, India in the Western Himalayas. Both the populations reveals tetraploid chromosome count of 2n=28 which is the first ever report for the species. The objective of the present research were to study the detailed meiotic course, microsporogenesis, and the effect of meiotic abnormalities encountered during different stages of meiosis I and II on pollen grain size and pollen fertility.

SummaryThe detailed meiotic behavior, chromosome number, morphological analysis and pollen fertility was studied in 10 populations of Melica persica belonging to family Poaceae from the cold desert region of Kinnaur. The collection and analysis of the species done on population basis showed a wide range of distribution with varied altitudinal habitats, and two distinct morphotypes-purplish red and creamy white colored spikelets. The collected morphotypes do not show any cytological variations and all the populations showed the same diploid chromosome number (2n=18 based on x=9). Two populations of white and one population of red morphotypes showed normal meiotic behavior while the rest of the seven populations showed a number of meiotic abnormalities including cytomixis, chromosome stickiness, unoriented bivalents, laggards, bridges and abnormal microsporogenesis in the form of dyad, leading to reduction in pollen fertility. In the present study, the existence of two morphotypes and the phenomenon of cytomixis have been reported for the first time in this grass species.

Summary Soil stabilization is a serious exercise, which involves establishing and implanting resistive measures against soil erosion. Growing grasses is one of the most efficient and cost effective methods of stabilizing banks of slopes and newly created slopes from landslides, etc. Selection of suitable candidate species for this job is an important question. Male meiotic studies have been carried out on two soil stabilizing grass species, Eremopoa persica and Pennisetum lanatum, of family Poaceae from district Kinnaur, Himachal Pradesh, a cold desert region of the Northwestern Himalayas, India. Meiotic analysis of three populations of Eremopoa persica revealed that all populations exist at a haploid chromosome number of n=21, a new hexaploid cytotype recorded for the species at world level. The present count of n=9+1-3 B in Pennisetum lanatum is the first report of B-chromosomes. The meiotic course varies from normal to abnormal in various populations, thus reducing the pollen fertility in the analyzed populations.

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