Althaea officinalis L. seed productivity in natural coenopopulations of the Republic of Bashkortostan (Russia)

The data on reproductive species biology which show the degree of plant viability and its ability to renewal and distribution are of great importance for assessing the state of natural populations along with other criteria. Our objective was to study the features of reproductive biology of A. officinalis in the Bashkortostan Republic. The results of studying Althaea officinalis seed productivity in 8 coenopopulations located in the flood plains of rivers of the steppe zone of the Cis-Urals are presented. We established that the species is found on the northern border of its range and is encountered in the steppe zone of the Cis-Urals. It forms small groups in the flood plains of steppe rivers. This species gained the greatest distribution in the flood plain of the Dyoma River, the second-large river of the Cis-Urals of the Bashkortostan Republic. The extent of the anthropogenous impact on A. officinalis habitats is various: from undisturbed hayfields to heavily trampled pastures. The number of studied coenopopulations is low - from 70-100 to 1-1.5 thousands of individuals. The density of most coenopopulations is low: 1-4 individuals per m, only in one coenopopulation it is high (about 20 individuals per ш). To study the seed productivity, we considered the number of reproductive shoots, the number of flowers and fruits per a reproductive shoot; counted the number of seeds and seed buds in the fruits; determined the flowering percentage and the seed setting percentage per a fruit, potential seed productivity, real seed productivity and the seed productivity coefficient. Our researches showed that all seed productivity indicators in natural coenopopulations vary greatly among populations.There are from 38 to 130.7 flowers per 1 generative shoot, of which from 33.8 to 125.8 form into fruits. The fruitflowering percentage in all coenopopulations is high and, on the average, makes 84%. The seed setting percentage is also high - on the average, 87.7%, the coefficient of seed efficiency is 88%. A. officinalis is characterized by quite high seed efficiency - from 1 243 pieces to 13761 pieces of seeds per plant. The comparison of separate coenopopulations according to variability of signs shows that, in most cases, the variation coefficient has a normal variation. The carried-out dispersive analysis showed statistically significant influence of the factor on all studied indicators of seed efficiency. The level of factorization made from 18.8 to 55.1%. The seed length makes 2.1-2.4 mm and the width - 1.7-1.9 mm. Two cenopopulations have the maximum values according to the majority of seed productivity indicators, where sufficient moistening and the existence of moderate disturbances are noted.

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