Вплив синтетичних стимуляторів росту на морфофізіологічні характеристики та біологічну продуктивність культури картоплі

Effect of the synthetic plant growth stimulators on growth, development and productivity of potato crops has been studied. It is established that the use of gibberellic acid, 1-naphthylacetic acid and 6-benzylaminopurine is highly effective means for regulating morphogenesis and productivity of potato. It is found that the linear dimensions of potato and weight of rаw and dry matter of the whole plant increaseonly upon applying gibberellic acid. Other growth regulators have not changed the indexes significantly. The number of leaves per plant, weight of rаw and dry matter of leaves increased under the influence of gibberellic acid and 6-benzylaminopurine, that was one of the main pre-requisites to strengthen the photosynthetic activity of plants. All growth stimulators increased the leaf area. Gibberellic acid and 1-naphthylacetic acid reasoned the thickening of the chlorenchyma and growth of columnar cells of the parenchyma. Increasein leaf area and proliferation of mesophyll resulted in the increase of the leaf index and specific surface density of the leaf. Changes of phytometric and mezo-structure indexes of leaves and increase in the amount of chlorophyll under the influence of growth regulators contributed to intensification of photosynthetic activity of the leaf apparatus, and its consequence was the increase in net photosynthetic productivity and crop yields. The use of gibberellic acid and 6-benzylaminopurine proved to be the most effective. Досліджено вплив синтетичних стимуляторів росту рослин на ріст, розвиток і продуктивність культури картоплі. Застосування гіберелової кислоти, 1-нафтилоцтової кислоти та 6-бензиламінопурину – високоефективний засіб регуляції морфогенезу та продуктивності картоплі. Лінійні розміри рослин картоплі та маси сухої та сирої речовини цілої рослини збільшувалися лише за умов застосування гіберелової кислоти. Інші регулятори росту показників достовірно не змінювали. За дії гіберелової кислоти та 6-бензиламінопурину збільшувалася кількість листків на рослині, маса сирої та сухої речовини листя, що є однією з основних передумов посилення фотосинтетичної активності рослини. Усі три стимулятори росту збільшували площу листкової поверхні. Гіберелова та 1-нафтилоцтова кислоти зумовлювали потовщення хлоренхіми та зростання об’єму клітин стовпчастої паренхіми. Наслідком збільшення площі листя та розростання мезофілу стало підвищення листкового індексу та питомої поверхневої щільності листків. Зміни фітометричних і мезоструктурних показників листків та збільшення вмісту суми хлорофілів за дії регуляторів росту сприяли посиленню фотосинтетичної активності листкового апарату, наслідком чого було підвищення показника чистої продуктивності фотосинтезу та зростання урожайності культури. Найефективнішим було застосування гіберелової кислоти та 6-бензиламінопурину. Досліджено вплив синтетичних стимуляторів росту рослин на ріст, розвиток і продуктивність культури картоплі. Застосування гіберелової кислоти, 1-нафтилоцтової кислоти та 6-бензиламінопурину – високоефективний засіб регуляції морфогенезу та продуктивності картоплі. Лінійні розміри рослин картоплі та маси сухої та сирої речовини цілої рослини збільшувалися лише за умов застосування гіберелової кислоти. Інші регулятори росту показників достовірно не змінювали. За дії гіберелової кислоти та 6-бензиламінопурину збільшувалася кількість листків на рослині, маса сирої та сухої речовини листя, що є однією з основних передумов посилення фотосинтетичної активності рослини. Усі три стимулятори росту збільшували площу листкової поверхні. Гіберелова та 1-нафтилоцтова кислоти зумовлювали потовщення хлоренхіми та зростання об’єму клітин стовпчастої паренхіми. Наслідком збільшення площі листя та розростання мезофілу стало підвищення листкового індексу та питомої поверхневої щільності листків. Зміни фітометричних і мезоструктурних показників листків та збільшення вмісту суми хлорофілів за дії регуляторів росту сприяли посиленню фотосинтетичної активності листкового апарату, наслідком чого було підвищення показника чистої продуктивності фотосинтезу та зростання урожайності культури. Найефективнішим було застосування гіберелової кислоти та 6-бензиламінопурину.

Influence of chlormequat chloride and treptolem mixture on the quality of products Helianthus Annuus L.

The article is devoted to studying of the effect of a growth regulators mixture of chlormequat chloride and treptolem on the sunflower seeds quality indicators. The results of three years studies suggest that the reduction of protein nitrogen content in seeds and the increase of phosphorus content has occurred due to processing of sunflower crops by means of mixture of growth inhibitor with anti-gibberellin mechanism of action – chlormequat chloride and cytokinin stimulator treptolem. Herewith the content of potassium by variants of experiment has not significantly changed. Such changes in the contents of nutrition elements positively influence the process of oil accumulation and improve the quality of sunflower meal. The content of reducing sugars, saccharose and starch in sunflower seeds for actions mixtures of retardant with the stimulator was lower than in the control regardless of the weather conditions of vegetation. We have found that mixture of multidirectional growth regulators has increased the oil content in sunflower seeds. Herewith the quality of oil has depended substantially on weather conditions of vegetation. The mixture of preparations in hot and droughty vegetation conditions in 2007 y. has led to increase the number of saponification, essential number, glycerine content and has not changed the indicator of iodine number. The growth of oil unsaturation depends on sufficient water supply and comfortable temperature conditions. We have investigated that the correlation of unsaturated higher fatty acids to saturated in drought conditions during the action of the mixture of retardant and growth stimulator decreased compared with control and it has increased in optimal conditions. The residual quantity of the growth regulators in seeds has not exceed the maximum permissible concentration

Morphogenesis, pigment content, phytohormones and yield of tomatoes under the action of gibberellin and tebuconazole

One of the main tasks of contemporary plant physiology is regulation of growth and development of cultivated plants in order to optimize the productive process. The scientific community focuses its attention on the use of natural activators and growth inhibitors. We investigated the effect of foliar treatment with 0.005% solution of gibberellic acid and 0.025% solution of the anti-gibberellic preparation tebuconazole on morphogenesis, leaf mesostructure, content of photosynthetic pigments, balance of endogenous phytobrybrides and lymphocyte B and productivity of tomatoes. The vegetation experiment was carried out in the conditions of soil-sand culture in vessels with a 10-liter volume. The treatment was carried out in the budding phase. Morphometric parameters were measured every 10 days. The mesostructure of the middle tier leaves was studied in the fruit formation phase, and the chlorophyll content was determined in the raw material by spectrophotometric method. Analytical determination of endogenous phytohormones – indolyl-3-acetic (IAA), gibberellic acid and abscisic (ABA) acids and cytokinins – zeatin (Z), zeatin-O-glucoside (ZG), zeatinribozide (Znila) and isopentenyladenosine (iPA) was performed by high performance liquid chromatography – mass spectrometry (HPLC-MS). With gibberellic acid treatment plant height increased significantly, while with tebuconazole it decreased. Gibberellic acid increased the number of leaves per plant, and tebuconazole did not change it. The preparations increased the number of leaf blades per leaf, the total number of leaf blades per plant, the weight of the raw material of leaves, the area of leaf blades and the area of the leaves at the end of the study period. The dry matter weight of stems and roots under the action of gibberellic acid increased, and during the treatment of tebuconazole decreased. Gibberellic acid increased the dry matter of the whole plant, and tebuconazole did not change it. Under the action of tebuconazole the content of chlorophyll in the leaves increased, while under the action of gibberellic acid it decreased. Both regulators increased the volume of columnar parenchyma cells. Gibberellic acid increased the size of spongy parenchyma cells, while tebuconazole did not change them. It is revealed that the action of exogenous gibberellic acid in stems and leaves increased the content of endogenous IAA and gibberellic acid, and tebuconazole decreased their content. The ABA content in stems and leaves increased with tebuconazole treatments and decreased with exogenous gibberellic acid. The total cytokinin content in the leaves was higher than in the stems in both the control and the experiment samples. Growth regulators induced an increase in the cytokinin pool in leaves and a decrease in stems. Gibberellic acid increased the content of all five forms of cytokinins in the leaves, and tebuconazole increased only two isoforms. In the stems under the action of both growth regulators the content of Z decreased and iP increased. The content of ZR and iPA in stems increased after the application of the retardant and decreased under the action of growth stimulant. The ZG content exceeded the control after gibberellic acid treatment and was in trace concentrations under the action of tebuconazole. Growth regulators optimized the productivity of tomato plants: under the action of gibberellic acid there was a considerable increase in the number of fruits per plant, and after the use of tebuconazole the average weight of one fruit significantly increased. The obtained results demonstrated that anatomical-morphological and structural-functional rearrangements in tomato plants under the action of exogenous gibberellic acid and tebuconazole occurred against the background of changes in the balance and distribution of endogenous hormones. Increased photosynthetic activity, stimulation of growth processes of some plant organs and inhibition of others increased the biological crop capacity

Effect of retardants on morphophysiological index, productivity and dormant period of potato

It is set that the use of retardants are effective regulation of growth, morphogenesis, productivity and slowing the germination of tubers during storage products. The number of leaves per plant, weight of rаw and dry matter of leaves and their area increased because of better tillering for the actions of the drugs. That is one of the main preconditions enhance photosynthetic activity of plants. Changes of phytometric and mezostructure indexes of leaves and increase of chlorophyll content for the actions of the drugs contributed to the photosynthetic activity of leaf apparatus, because of that was increase of the net productivity of photosynthesis and increase productivity of the culture. The use retardant of tebuconazol was the most effective. Treatment retardants of potato tubers during the release of dormancy led to decrease in the intensity of germination, that contributes to the preservation of products

Fabrication of Worm-Like Nanorods and Ultrafine Nanospheres of Silver Via Solid-State Photochemical Decomposition

Worm-like nanorods and nanospheres of silver have been synthesized by photochemical decomposition of silver oxalate in water by UV irradiation in the presence of CTAB and PVP, respectively. No external seeds have been employed for the synthesis of Ag nanorods. The synthesized Ag colloids have been characterized by UV-visible spectra, powder XRD, HRTEM, and selected area electron diffraction (SAED). Ag nanospheres of average size around 2 nm have been obtained in the presence of PVP. XRD and TEM analyses revealed that top and basal planes of nanorods are bound with {111} facets. Williamson–Hall plot has revealed the presence of defects in the Ag nanospheres and nanorods. Formation of defective Ag nanocrystals is attributed to the heating effect of UV-visible irradiation

Crystal Phase Transitions in the Shell of PbS CdS Core Shell Nanocrystals Influences Photoluminescence Intensity

ABSTRACT We reveal the existence of two different crystalline phases, i.e., the metastable rock salt and the equilibrium zinc blende phase within the CdS shell of PbS CdS core shell nanocrystals formed by cationic exchange. The chemical composition profile of the core shell nanocrystals with different dimensions is determined by means of anomalous small angle X ray scattering with subnanometer resolution and is compared to X ray diffraction analysis. We demonstrate that the photoluminescence emission of PbS nanocrystals can be drastically enhanced by the formation of a CdS shell. Especially, the ratio of the two crystalline phases in the shell significantly influences the photoluminescence enhancement. The highest emission was achieved for chemically pure CdS shells below 1 nm thickness with a dominant metastable rock salt phase fraction matching the crystal structure of the PbS core. The metastable phase fraction decreases with increasing shell thickness and increasing Exchange times. The photoluminescence intensity depicts a constant decrease with decreasing metastable rock salt phase fraction but Shows an abrupt drop for shells above 1.3 nm thickness. We relate this effect to two different transition mechanisms for changing from the metastable rock salt phase to the equilibrium zinc blende phase depending on the shell thicknes

Surface Doping Quantum Dots with Chemically Active Native Ligands: Controlling Valence without Ligand Exchange

One remaining challenge in the field of colloidal semiconductor nanocrystal quantum dots is learning to control the degree of functionalization or valence per nanocrystal. Current quantum dot surface modification strategies rely heavily on ligand exchange, which consists of replacing the nanocrystal\u27s native ligands with carboxylate- or amine-terminated thiols, usually added in excess. Removing the nanocrystal\u27s native ligands can cause etching and introduce surface defects, thus affecting the nanocrystal\u27s optical properties. More importantly, ligand exchange methods fail to control the extent of surface modification or number of functional groups introduced per nanocrystal. Here, we report a fundamentally new surface ligand modification or doping approach aimed at controlling the degree of functionalization or valence per nanocrystal while retaining the nanocrystal\u27s original colloidal and photostability. We show that surface-doped quantum dots capped with chemically active native ligands can be prepared directly from a mixture of ligands with similar chain lengths. Specifically, vinyl and azide-terminated carboxylic acid ligands survive the high temperatures needed for nanocrystal synthesis. The ratio between chemically active and inactive-terminated ligands is maintained on the nanocrystal surface, allowing to control the extent of surface modification by straightforward organic reactions. Using a combination of optical and structural characterization tools, including IR and 2D NMR, we show that carboxylates bind in a bidentate chelate fashion, forming a single monolayer of ligands that are perpendicular to the nanocrystal surface. Moreover, we show that mixtures of ligands with similar chain lengths homogeneously distribute themselves on the nanocrystal surface. We expect this new surface doping approach will be widely applicable to other nanocrystal compositions and morphologies, as well as to many specific applications in biology and materials science

Molecular Chemistry to the Fore: New Insights into the Fascinating World of Photoactive Colloidal Semiconductor Nanocrystals

Colloidal semiconductor nanocrystals possess unique properties that are unmatched by other chromophores such as organic dyes or transition-metal complexes. These versatile building blocks have generated much scientific interest and found applications in bioimaging, tracking, lighting, lasing, photovoltaics, photocatalysis, thermoelectrics, and spintronics. Despite these advances, important challenges remain, notably how to produce semiconductor nanostructures with predetermined architecture, how to produce metastable semiconductor nanostructures that are hard to isolate by conventional syntheses, and how to control the degree of surface loading or valence per nanocrystal. Molecular chemists are very familiar with these issues and can use their expertise to help solve these challenges. In this Perspective, we present our group\u27s recent work on bottom-up molecular control of nanoscale composition and morphology, low-temperature photochemical routes to semiconductor heterostructures and metastable phases, solar-to-chemical energy conversion with semiconductor-based photocatalysts, and controlled surface modification of colloidal semiconductors that bypasses ligand exchange