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The paper gives the variation data related to some quantitative characters and anatomy of Phlox sibirica L. leaf blade. The most stable characteristics of Phlox sibirica leaf anatomy are the leaf thickness around the midrib, the length of upper mesophyll layer cells, the number of epidermal cells, and the stoma sizes, which, along with the peculiarities of mesophyll structure, conducting bundles and stomatal type, can serve as additional diagnostic characters for species identification. Phlox sibirica is classified as xerophyte-heliophyte morphological type.

Many researchers analyze the effect of water deficits on microsporogenesis, although few study the influence of flooding. This study reviewed the effects of drought and flood stress on pollen quality and quantity in Clivia miniata including pollen size, viability, germination, and number of pollen grains per anther while evaluating how stress influences these features. The study provides evidence that microsporogenesis of Clivia miniata is more sensitive to flooding than to drought. The studied pollen features can be ranked based on their degree of sensitivity to flooding in the following order: number of pollen grains per anther > pollen germination > pollen fertility > pollen size. A newly modified method of counting the number of pollen grains per anther was shown to be highly sensitive and can be applied to evaluate pollen productivity using a small number of plants.

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We studied the influence of superfine materials on the rooting ability and development of softwood cuttings of Ribes nigrum. The inhibiting effect of the soil amended with ZnO and Pt nanoparticles at the concentration of 5 mg/kg of substrate on the rhizogenesis of black currant cuttings was stated. On adding the suspension of ZnO nanoparticles the rooting ability of cuttings decreased by 32.3 %, and under the influence of Pt nanoparticles – by 41.4 %. The decrease in the morphometric parameters of development of the cuttings’ above-ground part and roots (growth amount, number of cratches and leaves, number of roots and their length) was observed. The change in the biochemical composition of leaves in the cuttings was stated. In the replication with zinc oxide the concentration of chlorophyll in leaves significantly decreased by 21.8 %. Under the influence of Pt the concentration of flavonoids in leaves increased by 48.8 %.

Definition of the growth and development characteristics of plants in varied light conditions is a key factor for the creation of highly efficient light facilities for plant cultivation. Experimental research was conducted using an LED irradiation facility with photosynthetic photon flux densities ranging from 0 to 261 μmol m−2 s−1 and a continuous spectrum with maxima at 445 and 600 nm. Under the maximum photosynthetic photon flux density (261 μmol m− 2 s−1) wheat germs demonstrated diminishing leaf surface with high values of specific leaf area, enhanced pubescence of ground tissues, increases in the number of stomata on the upper epidermis and palisade, and an increase in the thickness of the leaves as well as an increase in carotenoids but a decrease in the chlorophyll a+b/carotenoids relation. It was revealed that the optimum level of photosynthetic photon flux density for the referred spectrum was in the range from 82 to 100 µmol m−2 s−1, which may enable a reduction of irradiance under specific conditions during early development with no harm to the plants while minimizing energy consumption during cultivation.

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The influence of ZnO and Pt nanoparticles’ suspensions (5 mg/kg of soil) on the yielding capacity and fruit quality of Cucumissativus L. was studied. We found out that the soil amended with ZnO nanoparticle suspension enhanced cucumber yielding capacity by 36 %, and the fruits had more carotene, zinc and iron compared to the control. The soil amended with Pt nanoparticles did not influence cucumber yielding capacity, and the fruits contained more carotene and zinc. ICP-MS results showed that nanoparticles’ influence at the concentration under study did not result in accumulation of ZnO and Pt nanoparticles in fruits.