seed productivity

We have studied the characteristics of seed reproduction Artemisia 14 species from various parts of the Saratov region. It is shown that a population of five of them (A. vulgaris, A. salsaloides, A. dracunculus, A. glauca, A. austriaca) are characterized by high (at least 20-30%) frequency of gametophytic apomixis in plants, and three species (A. abrotanum, A. absinthium, A. armenica) have lower (10-15%) frequency of gametophytic apomixis.

The article presents the results of a long-term introduction of Tulipa sylvestris L. in the SB RAS Central Botanical Garden collection. Plants of the species T. sylvestris bloom abundantly and have a reproductive factor of 1–2 for the daughter bulbs. It was found that the short phase of fl owering is characterized by smooth temperature changes, the most dramatic for a long period. We also established a direct dependence of the duration of the fl owering period on the amount of precipitation during this period, the correlation coeffi cient was 0,7.

The monitoring of the frequency of apomixis was making in popu- lations of 7 species of Chondrilla in the south of european part of Russia. It is shown that the plants of 6 examined species (C. juncea, C. graminea, C. canescens, C. brevirostris, C. latifolia и C. acantho- lepis) are characterized by their ability to seed reproduction by apo- mixis. This fact is confirmed by results of a study of seed productivity of the species of the genus Chondrilla at the regime of blossoming without pollen and cytoembryological analysis megagametophytes of the same plants.

The results of researches of 7 coenopopulations of North American invasivespeciesHordeumjubatumL.(Poaceae)inthe Trans-Urals of the Republic of Bashkortostan. Hordeum jubatum spreads on the steppe zone of the region. It dominates over other plants and it is share of participation in the community is 45,5–60,5%. The density of grass invasive species – 9–18 plants per 1 m2.Each plant produces 35 to 68 shoots, on average, is more than 600 shoots per 1 m2. The biomass of the type is no more than 0.25 kg/m2. Seed production is 39–54 pcs.

Laburnum anagyroides Medik. (Leguminosae) is a promising ornamental woody plant, which is native to the Mediterranean. It is characterized by the following indicators of seed reproduction during introduction in the Lower Volga region: potential seed productivity is 5.24 ± 0.08 ovules on 1 ovary, real seed productivity is 1.53 ± 0.05 seeds per 1 fruit, the reproduction efficiency coefficient is 29.2%. Seeds quickly pass into a state of deep physical rest and cannot independently leave this state in spring.

Allium ramosum L. – type species of the subgenus Butomissa (Salisb.), Section Butomissa. The species has a fairly high seed productivity, which varies widely. This article presents the results of a study of seed productivity under the conditions of artificial phytocenosis of the Moscow Region in four commercial varieties of A. ramosum. In alluvial meadow soils, fruit setability was 88.9–95.8%, real seed productivity was fixed at 3.5–18.5 g/plant, 1000 seeds weight was 4.2–5.9 g. Average insemination was noted 3, 0–5.9 pieces/fruit.