the purpose of this study was to evaluate the species-environment relationships in arid and semi-arid rangelandsof nodushan, yazd. the plant species cover and the environmental variables were measured at 9 sites. soil sampleswere taken for measurement of 12 attributes in 0-10 cm and 10-80 cm layers. vegetation was classified using twowayindicator species analysis (twinspan). data was analyzed u...

The use of nonmetric multidimensional scaling as an ordination method has been studied by the use of simulated coenoclines and coenoplanes. It was found that the method always produced better ordinations than principal components analysis and in most cases better than reciprocal averaging, providing the multidimensional scaling was calculated using a space of the same dimensions as the simulate...

meiotic study was performed in 11 brassica napus cultivars considering chiasma frequency anddistribution, chromosome pairing, as well as the occurrence of b-chromosomes and their effects on chiasmafrequency. such cytogenetic pairing, along with agronomic characteristics, may be used in planninghybridization among the b. napus cultivars. all the cultivars studied possessed n=19 chromosome number...