Plant Biometric Parameters Research Articles

Features of growth of sorghum [Sorghum bicolor (L.) Moench] plants depending on the width of rows and seeding rate in the conditions of the Right-Bank Forest-Steppe of Ukraine

Purpose. To establish the optimal row spacing and so­wing rate of sorghum seeds of grain varieties ‘Dniprovskyi 39’ and ‘Vinets’, to substantiate their influence on the growing season and biometric parameters of plants in the Right-Bank Forest-Steppe of Ukraine. Methods. Field, laboratory, mathematical and statistical. Results. The most intensive growth and development of sorghum plants was observed when sowing seeds with a row spacing of 45 cm and a seeding rate of 200 thousand pieces/ha. In particular, the duration of the growing season under such conditions was the smallest: 108 days for the ‘Dniprovskyi 39’ variety and 106 days for the ‘Vinets’ variety. At the same time, the indicators of field seeds germination, plant height and stem diameter were maximum in the experiment: ‘Dniprovskyi 39’ – 88.7%, 137.3 cm and 1.7 cm, ‘Vinets’ – 86.9%, 121.8 cm and 1.6 cm, respectively. It was found that an increase in seeding rate reduced indicators of productive tillering, leaf area and weight per plant. The most intense tillering of sorghum plants was observed at a seeding rate of 150 and 200 thousand pieces/ha for all the studied variants of the row spacing: on average, up to two panicles well filled with grain per plant, depending on the varietal characte­ristics. At the rate of 250 thousand pieces/ha, tillering of plants in both varieties was somewhat weaker – 1.0–1.1 panicles per plant. The largest indicators of leaf surface area and weight of one plant were with a row spacing of 45 cm: 1528–2320 cm2 and 169.2–185.6 g in the variety ‘Dniprovskyi 39’ and 1476–2180 cm2 and 143.1–162.3 g in the variety ‘Vinets’ depending on planting density. Reduction of row spacing up to 15 cm and its increase up to 70 cm led to a decrease in the main parameters of plant growth and development. Conclusions. Sorghum plants developed better when sown with a row spacing of 45 cm and a seeding rate of 200 thousand pieces/ha, which were recommended for growing crops in the conditions of the Right-Bank Forest-Steppe of Ukraine.

Development of technology elements for growing leek seedlings for open ground in the Non-Chernozem zone

Relevance and methods. Leek is one of the most promising onion crops for industrial cultivation in the Non-Chernozem zone, which has medicinal properties and high nutritional value. The results of studying the technological features of leek cultivation in the open ground of the Moscow region are presented. The studies were carried out in 2019-2020 on the territory of the “Vegetable Experimental Station named after V.I. Edelstein". We studied the influence of the feeding area of leek seedlings on the biometric parameters of plants and the quality of products. The object of the study is the variety Karantansky, experimental options: 1) seedling feeding area – 6 cm2 (control), 2) seedling feeding area – 8 cm2 , 3) seedling feeding area – 10 cm2 . The objects of research to study the content of ascorbic acid were leek varieties: late-ripening – Karantansky (standard), Bandit, Dobry Molodets, mid-ripening – Columbus, Hobot slona.Results. It is noted that the feeding area during the seedling period does not significantly affect the biometric parameters of leek plants: leaf area, plant weight, leek pseudostems diameter. Therefore, during the period of growing seedlings, from the point of view of rational use of the area in the seedling department, it is recommended to use the minimum feeding area – 6 cm2 . It was also found that the studied varieties accumulate ascorbic acid in different ways in various plant organs. The maximum content of ascorbic acid was noted in the leek pseudostems of the control late-ripening variety Karantanskiy – 23.6 mg%. The minimum values are for Dobry Molodets (11.8 mg%) and Hobot Slona (11.9 mg%).

Rice responses to silicon addition at different Fe status and growth pH. Evaluation of ploidy changes

It has been described in rice that Si only plays a physical barrier that does not allow Fe to enter cell apoplast, causing Fe deficiency responses even under Fe sufficiency growth conditions. Most of the conclusions were attained at acidic pH, but rice is also grown at calcareous conditions, which especially induce Fe deficiency in the plants. In this study, we assay the effect of Si in rice suffering both Fe deficiency and sufficiency in hydroponics at two pHs (5.5 and 7.5). Plant biometric parameters, ROS concentration, enzymatic activities, and total phenolic compounds, as well as ploidy levels, have been determined. In general, both pHs promoted similar rice responses under Fe sufficiency and deficiency status, but at pH 7.5, stress was favored. Flow cytometry studies revealed that Fe deficiency increased the percentage of cells in higher ploidy levels. Moreover, under this Fe status, Si addition enhanced this effect. This increase contributed to maintaining chloroplast structure which may have preserved antioxidant activities, and fortified cell walls, diminishing Fe uptake. The first is considered a beneficial effect as plants presented acceptable SPAD values, well chloroplast structure, and qualitatively high fluorescence observed by confocal microscopy, even under Fe deficiency. But contributes to intensify the Fe shortage, by decreasing apoplast Fe pools. In summary, Si addition to rice plants may not only behave as an apoplastic barrier but may also protect plant chloroplast and alter the plant endoreplication cycle, giving a memory effect to cope with present and future stresses.

Effect of light spectrum on growth, development, and mineral contents of okra (Abelmoschus esculentus L.)

Abstract Influence of the light spectrum on growth, development, and nutrients contents of okra was studied by growing okra (Abelmoschus esculentus L.) under three different LED-based irradiations defined by their peak wavelength at 455.45 ± 1.80 nm (B455), 522.27 ± 1.46 nm (G522), and 635.03 ± 1.33 nm (R635), respectively in the blue, green, and red regions of the visible spectrum. The photosynthetic photon flux density (PPFD) of 200 μmol m−2 s−1 was provided by the LEDs for 18 h daily. Leaves macronutrients and micronutrients concentration and plant biometric parameters were measured 60 days after sowing; the evolution of biometric parameters was also monitored during the growing period. Results related to biometric parameters have shown that highest leaf area, plant height, and fresh and dry weight were achieved under B455 light; both R635 and G522 lights produce the highest quantity of leaves; and largest stem diameters were observed under B455 and G522 lights. Regarding mineral contents, highest calcium, phosphorus, and manganese concentrations were obtained under R635 light; highest sodium content was observed under G522 light; and the highest nitrogen content was obtained under both B455 and G522 lights. However, there were no significant differences observed for potassium, magnesium, and zinc concentrations among the three light treatments. These results revealed that selective spectrum in artificial lighting design can be strategically used to optimize the plant growth, development, and mineral contents uptake under controlled environments.

Вплив краплинного зрошення та навантаження суцвіттями на ріст і розвиток маточних кущів винограду

The high yield of grafted grape seedlings and their quality depend on many factors, including the quality of graft and rootstock components, which in turn is determined by proper care of the mother plantations of grape. Their farming techniques should be aimed at better growth and maturation of shoots. On mother bushes, the technological reception of shoot fragments is mandatory, partial removal of inflorescence is not so common in the agricultural techniques of mother plantings, but has a positive effect on the overall development of plants. Mother plantings should be irrigated if possible, as insufficient moisture supply negatively affects the condition of the bushes throughout the growing season and winter. In this work, the effect of partial removal of inflorescence (load of inflorescence 100, 75 and 50% of their total number) on mother bushes and the effect of different irrigation regimes (levels of pre-irrigation soil moisture 90, 80 and 70% of the lowest moisture capacity) on the condition of mother plantations, in particular on physiological, biochemical and biometric parameters of plants. It is shown that irrigation of bushes and reduction of inflorescence load to 50 and 75% of their total number stimulated the accumulation of chlorophyll in the leaves of mother plants, improved watering of leaf tissues, increased respiration during active growth and development of grapes. There is a positive effect of irrigation and reducing the load of inflorescence bushes to 50 and 75% on the biometrical parameters of mother grape bushes. The largest values of the total length of shoots and the degree of their maturation were in the bushes of variants with 90% the lowest moisture capacity, 50% inflorescence, 80% the lowest moisture capacity 50% inflorescence, 70% the lowest moisture capacity 50 and 75% inflorescence. Thus, effective irrigation regimes and reducing the load of inflorescence contributed to the growth of medium and strong full-fledged shoots, which are more productive.

Nutrient Extraction in Pansy Fertigated with Pure, Diluted, Depurated and Phytodepurated Leachates from Municipal Solid Waste

The disposal of municipal solid waste (MSW) in landfills might result in serious environmental pollution. The goal of the present assay was to assess if MSW wastewater (pure or treated) can be used as a potential source for fertilizers, studying its effects on plant biometric parameters as well as on anion concentrations and anion partitioning of the bedding plant Viola × wittrockiana Gams. (pansy), to detect possible harmful impacts on plants. The treatments tested were: W9.0 (pure wastewater, EC 9.0 dS m−1), W4.5 (diluted wastewater, EC 4.5 dS m−1), DW4.5 (depurated wastewater, EC 4.5 dS m−1), PW4.5 (phytodepurated wastewater, EC 4.5 dS m−1), and T (tap water, the control, EC 1.5 dS m−1). The treatment with pure wastewater negatively affected plant fresh weight, water content (on a fresh weight basis), leaf area, plant height and width, and the number of leaves and flowers due to an accumulation of SO42− in plant tissues. Phytodepurated wastewater improved plant fresh weight, water content, plant height and width, the number of leaves and flowers, and reduced the leaf area because this treatment decreased SO42− concentrations in wastewater by half. Pansy plants also showed high levels of nutrients (N, P, and Mg) when compared with fertigation with pure and diluted landfill leachate. These results show that phytodepurated wastewater from MSW can be used for the fertigation of pansy plants.

SOIL MULCHING AS AN AGRICULTURAL METHOD FOR GROWING ZUCCHINI IN CONDITIONS OF RIGHT BANK FOREST-STEPPE

It has been established that the mulching materials was carried out by influence on the biometric parameters of plants and the production of zucchini yield in the years of research. According to research results, the greatest length of stem in the flowering stage was observed in plants mulching soil with black agro-textile and plastic film, black perforated, varieties Zolotynka – and 63,6 – 61,3 cm, varieties Chaklun and 62,4 – 61,0 cm, where the increase relative to the control was 3,3–5,6 cm. The greatest number of leaves at flowering stage was observed in varieties Zolotynka for soil mulching with black agro-textile – 22,5 PCs/plant, black perforated polyethylene film – 24,0 PCs./plant, which is 4,8 – 6,3 PCs/plant more of the variant without mulch. The variety Chaklun, a significant difference was on the options for soil mulching with black agro-textile – 23,0 PCs/plant and black polyethylene film perforated to 23,5 PCs/plant, 5,4 and 5,9 PCs/plant more control. An important indicator in evaluating biometric parameters of the zucchini is leaf area. The highest it has been for mulching the soil with black agrotextile and plastic film, black perforated, varieties Zolotynka to 6,8 and 7,1 thousand m2/ha, varieties the Sorcerer – 8,2 and 8,5 thousand m2/ha, of 0,7–1,0 and 0,8–1,1 thousand m2/ha more control. Large productivity on average was noted for mulching the soil with black agro-textile and plastic film, black perforated, varieties Zolotynka – of 49,7 and 53,3 t/ha, 7,3 and 10,9 t/ha more control. The variety Chaklun all the studied variants had significantly higher yields, but the highest it has been for mulching the soil with black Agro-textile and plastic film, black perforated – between 90,0 and 97,8 t/ha, respectively, and 20,2 to 28,0 t/ha more in comparison with the control. The greatest number of fruits was noted for mulching the soil with black agro-textile and plastic film black perforated : y grade Zolotynka – 14,7–14,6 PCs/plant, varieties the Chaklun of 26,6–29,8 per PCs/plant. The highest fruit weight was observed in varieties Zolotynka for soil mulching with black agro-textile – 303 g, a polyethylene film, black perforated – 314 g sawdust and – 302 g, which is 15,0–27,0 g more control. The variety Chaklun large mass of the fetus had options for mulching the soil with black agro-textile – 305 g and black perforated polyethylene film – 319 g, which exceeded the control at 14-28 g. The diameter of the fruit greatly from the use of mulching materials did not change, but their use was noted a positive trend. So, for the sorts Zolotynka the diameter of the fruit for soil mulching with different materials grew by 0,1–0,3 cm, for a variety of Chaklun – 0,1-0,2 see. Key words: zucchini, variety, multi-valley material, biometrics, productivity.

ЕФЕКТИВНІСТЬ ГУМІНОВИХ СТИМУЛЯТОРІВ ЗА УМОВИ ПЕРЕДПОСІВНОЇ ОБРОБКИ НАСІННЯ ЗЕРНОВИХ КУЛЬТУР

Гумінові речовини є важливим елементом технології вирощування польових культур, застосовую-чи які можна впливати на ріст і розвиток рослин фактично на всіх етапах органогенезу. Метою до-сліджень було виявити ефективність протруйників, гумінових стимуляторів на процеси проростан-ня насіння, формування ознак продуктивності ячменю ярого і пшениці озимої та перспективи їхньо-го використання у виробництві. У ході проведення досліджень використано такі наукові методи: аналіз, синтез, польовий, статистичний. Статистично встановлений характер взаємозв’язків оз-нак, які вивчали в експерименті, свідчить, що головними параметрами формування продуктивності пшениці озимої є маса зерна з рослини та продуктивне кущіння, а для ячменю ярого – маса 1000 зе-рен. Проте урожайність зернових культур визначається значно складнішою системою, оскільки елементи структури продуктивності культур, зокрема маса 1000 зерен, маса зерна з рослини та кількість продуктивних пагонів прямо впливають на урожайність (r=0,34–0,71), а вона своєю чер-гою залежать від маси корінців проростка. Розраховано, що між масою корінців проростка і кількі-стю продуктивних стебел кореляція є прямою із середнім ступенем зв’язку ( r=0,54), а між масою корінців проростка і масою зерна з рослини кореляційний зв’язок сильний (r=0,85). За результатами досліджень встановлено, що застосування гуматів позитивно впливало на наростання надземної маси ячменю ярого. За умови обробки насіння пшениці озимої відзначено істотний закономірний вплив цього елементу технології на біометричні параметри рослин, однак суттєву роль відігравали і сортові властивості культури. Застосування гумінових препаратів для передпосівної обробки насін-ня UB for seeds і 1R Seed treatment призвело до зростання маси проростка на 8–19,6 %, а на пшениці – в межах 11–16 %. Потенційна врожайність зросла відповідно на 8,8–12,7 та 28,3 % відповідно.

New Uses of Treated Urban Waste Digestates on Stimulation of Hydroponically Grown Tomato (Solanum lycopersicon L.)

One strategy to re-use solid urban wastes is the production of energy by anaerobic digestion. This process also generates high volume of digestates, which are frequently disposal in landfills. The aim of this work is to assess anaerobic digestates as agricultural inputs. Three different biomethanation wastes from different plants were collected. Firstly, a complete physico-chemical characterization of the wastes was done according to the Spanish regulation, showing that the materials had the 90% of the particles below 25 mm, high values of pH, electric conductivity, organic matter, humic acids and soluble nutrients such as NO3−, SO42−, Ca2+, Mg2+, PO43− and K+. Total concentrations of heavy metals and microbiological parameters were below the threshold levels allowed for agricultural use. The wastes were then treated with a strong acid and a strong base having two different solutions (ATr and BTr, respectively) which were evaluated as biostimulants for tomato plants in hydroponic culture. Those liquid extracts, ATr and BTr, demonstrated their biostimulant ability towards root system of tomato enhancing the hair root density and plant biometric parameters including plants weight and chlorophyll content. This work demonstrates the re-use feasibility of treated digestates in agriculture as fertilizers and more over as feedstock for biostimulants production.

ЕФЕКТИВНІСТЬ БІОСТИМУЛЯТОРІВ ЗА УМОВИ ПЕРЕДПОСІВНОЇ ОБРОБКИ НАСІННЯ СОНЯШНИКУ

У сучасних технологіях вирощування соняшника (Helianthus annuus L.) ефективним заходом ніве-лювання негативного впливу несприятливих абіотичних чинників та управління реалізацією біологіч-ного потенціалу продуктивності культури все більшого поширення набувають регулятори росту рослин. Метою досліджень було з’ясувати зміну біометричних параметрів рослин та продуктивно-сті посівів соняшнику за умови пливу біостимуляторів росту в умовах Лівобережного Лісостепу Ук-раїни. У ході проведення досліджень використано такі наукові методи: аналіз, синтез, польовий, статистичний. Результати досліджень свідчать, що стимулятори росту рослин сприяли приско-ренню проростання насіння, інтенсифікації ростових процесів, скороченню тривалості міжфазних періодів. Встановлено, що найбільш ефективний вплив на формування та функціонування асиміля-ційної поверхні рослин спостерігали у разі поєднання допосівної обробки насіння препаратом Марс ЕLBi (300 мл/т) та позакореневого підживлення посівів у фазу 5–6 листків стимулятором Ендофіт L1 (20 мл/га), де площа листкової поверхні посівів становила 80 тис. м2/га або перевищувала конт-роль на 33,1 %. За застосуванням рістрегулюючих речовин відзначено збільшення маси насіння з ко-шика на 3,1–4,4 г або 5,7–8,1 % та маси 1000 насінин на 5,2–7,5 г або 10,3–14,9 % щодо контрольно-го варіанту. З’ясовано, що найбільш сприятливі умови для формування врожаю соняшника створю-валися за умови допосівної обробки насіння культури біостимулятором Марс ЕLBi та листкового підживлення посівів препаратом Ендофіт L1. Приріст урожайності насіння соняшника порівняно з контролем становив 0,34 т/га або 12,7 %. Ефективним також виявилося застосування вищезазна-чених препаратів лише для передпосівної обробки насіння, яке забезпечило підвищення урожайності соняшника, відповідно, на 0,30 і 0,21 т/га.

Uticaj klimatskih uslova na rast i razvoj CichoriumEndivia(L) u leto-jesen u plastenicima u Lenjingradskoj oblasti, Rusija

The paper discusses the results of the study of the effect of climatic factors on the yield and biometric indicators of various varieties of endive chicory (Cichorium endivia (L.)) over a two-year study grown in the summer-autumn period in the plastic greenhouses on the experimental plots of the St. Petersburg Agrarian University, Pushkin, Russia. The plants of the genus Chicory are known and valued for their unique medicinal and nutritional properties. Total of 14 varieties of domestic and foreign Cichorium endivia breeding were studied. The study was carried out in 2015 and 2016years that were sharply differed in the amount of precipitation and temperature. The climate of Leningrad region is characterised with humid and long-lasting cold season. The aim of the research was to identify the variety of endive chicory that is most suitable and tolerant for the climatic conditions of Leningrad region, Russia. During the growing season the plant biometric parameters such as plant height (cm), rosette diameter of leaves (cm), and number of leaves (pieces) were measured. During harvesting, additional parameters such as biomass of plants and leaves, the area of the assimilation surface were determined. The decrease in plant biometric parameters during the phenological observations in September 2016 was associated with an increased amount of precipitation in July-August. The results showed that the variety "Broad Betavian fullhearted" was the most sensitive to the adverse effects of weather, showing the largest variation in biometrics over the studied years. In plants of this variety the mass of leaves decreased by 9.2 times, the area of the assimilation surface was reduced by 11.6 times, while the crop shortfall in 2016 was almost 90%. The varieties "Green curled" and "Scarola bionda" were the most tolerant to weather conditions. These varieties were characterized by the maximum yield in both years of research: "Green curled"-7.90 kg/m 2 and 2.87 kg/m 2 , "Scarola bionda"-8.06 kg/m 2 and 2.84 kg/m 2 in 2015 and 2016, respectively. Generally, the result of the study showed that most of the studied varieties were sensitive to the amount of precipitation and the number of sunny days. The study made it possible to identify the most sensitive and most tolerant varieties of endive chicory for growing in the Leningrad region.

A Seed Coating Delivery System for Bio-Based Biostimulants to Enhance Plant Growth

A novel delivery method for the application of bio-based biostimulants as seed coatings was developed using different sources of liquid and powder forms of vermicompost and soy flour. Micronized vermicompost (MVC) and soy flour (SF) were mixed in different combinations as dry seed coating blends and applied using rotary pan seed coating equipment. The physical properties of coated seeds were measured, and as binder concentration increased, coating strength increased. The rates and percentages of germination of the newly developed coating formulations of SF+MVC did not decrease the germination parameters and were not significantly different than the control. However, the SF, SF with concentrated vermicompost extract, and SF + MVC from dairy manure increased the seedling vigor index by 24, 30, and 39 percent, respectively, compared to the control. Plant biometric parameters and nitrogen uptake per plant were also significantly higher for SF and SF+MVC coated seeds than the control, in a greenhouse environment. This is the first seed coating study to show an enhancement of plant growth with vermicompost, and vermicompost in combination with a plant-based protein that serves as a dry seed coating binder and biostimulant, respectively. Seed coatings developed in this study can serve as a model for development of the delivery systems of seeds for the application of bio-based biostimulants to enhance early plant growth.

The Efficiency of Planting Stock of Some Tree-Shrubs in Armenia in Open-Air Hydroponics Conditions

The question of nature conservation became one of the most important in the world. It especially concerns to the countries with dry climate, such as Armenia, where auto recovery possibility of forests is excessively low. Gradual disappearance of forests, green areas is due to human non-competent acting, climate change, which aggravates present ecological crisis. One of the important steps for solution of this problem is the recovery of forests, green areas that requires the existence of huge amount of saplings. The use of open-air hydroponics is one of the best versions to receive healthy, qualify saplings. We studied and developed open-air hydroponic methods and biotechnologies of cultivation of 25 species of tree-shrubs important for the landscaping and forest recovery. There was studied the influence of nutrition solution offered by Davtyan G.S. and used in our Institute many years and its modified variants with the changes of main nutrients elements ratio on the biometric parameters of plants. Received results showed that saplings grown in open-air hydroponics conditions have strong root system, provide high rooting, which is very important in the recovery of forests, green areas, especially today’s ecological critical conditions of forest zones.

Isolation and Characterization of Antagonistic Bacteria Paenibacillus jamilae HS-26 and Their Effects on Plant Growth.

Soilborne pathogens affect plant growth and food production worldwide. The application of chemical fertilizers and pesticides to control plant diseases has harmful effects; fortunately, plant growth-promoting rhizobacteria can be used as a potential alternative strategy. Here, Paenibacillus jamilae HS-26 was selected for its highly antagonistic activity against several soilborne pathogens. The bacterium synthesized hydrolytic enzymes and released extracellular antifungal metabolites and volatile organic compounds—primarily, N, N-diethyl-1, 4-phenylenediamine, which was detected by gas chromatography-mass spectrometry and shown to inhibit fungal mycelial growth. Furthermore, HS-26 was useful for nitrogen fixation, phosphate and potassium solubilization, and siderophore and indoleacetic acid production. In vitro tests and pot experiments revealed that HS-26 considerably increased plant biometric parameters. Illumina MiSeq sequencing data showed a significant reduction in soilborne pathogens and increase in beneficial bacteria in the wheat rhizosphere after treatment with strain HS-26.

Introduction of new niche crop sweet potato (Ipomoea batatas L.) in the eastern forest-steppe of Ukraine

Aim. To analyze introduced sweet potato accessions in the conditions of cultivation in the Left-Bank forest-steppe of Ukraine. Results and Discussion. Thirteen introduced sweet potato accessions bred in Ukraine and other countries were evaluated in the conditions of the eastern forest-steppe of Ukraine. We found that the genotypes greatly differed in the growing period length, biometric parameters of plants and performance. Early-ripening accessions were V-1, V-6, A-7, Bonita; mid-ripening - Orlean, D-2 and Murasaki. Late-ripening accessions were the most numerous: Betty, Purpur, Blanka, J-12, Eernandes, and Okinawa. The stem length varied a lot. All the mid-ripening accessions formed long, climbing stems. The variability range was analyzed for the number of additional shoots, internode length, leaf number, root tuber shape, and pulp color. The highest yield of sweet potato root tubers was obtained from dessert accession D-2 (112 t/ha), with a marketability of 88%. Table accession V-6 also gave a high yield (87 t/ha), and the marketability of root tubers was 81%. Based on to the research results, two applications for new varieties of sweet potato, Admiral (obtained by clone breeding, selection from the D-2 genotype) and Slobozhanskiy Rubin (selection from the V-6 genotype), were submitted. Conclusions. Thirteen introduced sweet potato accessions bred in Ukraine and other countries were evaluated in the conditions of the eastern forest-steppe of Ukraine. It was found that the genotypes greatly differed in the growing period length, biometric parameters of plants and performance. Based on to the research results, two applications for new varieties of sweet potato, Admiral (obtained by clone breeding, selection from the D-2 genotype) and Slobozhanskiy Rubin (multi-year selection from the V-6 genotype), were submitted. Keywords: Ipomoea batatas L., sweet potato, introduction, niche crops, genotype.

Changes in sugar metabolism associated to stem bark thickening partially assist young tissues of Eriobotrya japonica seedlings under boron stress

Boron (B) toxicity frequently affects plant performances and productivity, especially in arid and semi-arid environments. In this experiment, loquat seedlings were subjected to 25 μM (control) or 400 μM B (B excess) to test the hypothesis that (i) B alters sugar/polyol metabolism in polyol-producing tree species as loquat and (ii) changes of leaf and stem anatomy assist young tissues against toxic effect of B. Gas exchange was monitored from the beginning of the experiment (FBE) till one week after the first visible symptoms of B toxicity appeared in the upper part of the stems (147 d FBE). At 147 FBE, plant biometric parameters and pattern of B accumulation, leaf and stem anatomy, chlorophyll a fluorescence kinetics as well as biochemical measurements were assessed in top (asymptomatic) leaves and upper stem bark. Boron accumulated principally (in the row) in top leaves > top bark > top wood in B-stressed plants, but no changes in allocation pattern were found between controls and B-stressed plants. Excess B promoted the increase in the spongy layer of top leaves and caused the development of cork and numerous collenchyma cells with increased cell wall thickness. This mechanism, which has never been described before, can be considered an attempt to store excessive B in tissues where B ions are less harmful. The accumulation of sorbitol (B-complexing polyol) in top leaves and stem bark can be considered as a further attempt to detoxify B excess. However, B toxicity drastically affects the photosynthetic rate of top leaves, mainly due to non-stomatal limitations, i.e., reduction of ambient CO2 use efficiency and of photosystem II (PSII) efficiency, modification of the partitioning excess energy dissipation in PSII, thus leading to an increased level of lipid peroxidation. Our results suggest that changes in sugar metabolism associated with leaf and stem bark thickening partially assist (but not totally preserve) young tissues of loquat plants under B stress.

Effects of municipal solid waste- and sewage sludge-compost-based growing media on the yield and heavy metal content of four lettuce cultivars.

Compost has been recently suggested as an alternative to peat for the preparation of growing substrates in soilless cultivation systems. However, some physico-chemical properties of compost may reduce plant performance and endanger the quality of productions, in particular for possible heavy metal accumulation in edible parts. This study aims at evaluating the suitability of a municipal solid waste compost (MSWC) and a sewage sludge compost (SSC) as components of growing media for the soilless cultivation of lettuce (Lactuca sativa L.). Heavy metal content of SSC complied with legislation limits but, in MSWC, it exceeded (Cu, Pb) or was very close (Cd, Zn) to safe limits. A greenhouse experiment was carried out by cultivating four lettuce cultivars ("Maximus," "Murai," "Patagonia," and "Aleppo") in pots containing a mixture of MSWC and perlite (MSWC + P), SSC and perlite (SSC + P), or peat and perlite (peat + P), the latter used as control. Plant biometric parameters measured after 72days of growth revealed that the yield of plants cultivated on SSC + P was similar to control plants, independently of the cultivar. Conversely, MSWC + P suppressed in general the biomass production, especially for Murai and Patagonia cultivars. Compared to peat + P, both compost-based substrates reduced the leaf accumulation of heavy metals, with a major effect in Maximus plants. The levels of Cd and Pb in the edible part were always below the safe limits imposed by European regulation. Therefore, risks of heavy metal intake in food chain associated with the replacement of peat with compost in the growing media are negligible, even when a compost with a significant amount of heavy metals is used. Besides compost quality monitoring, also an appropriate varietal choice is crucial to obtain good yields and safe products.

Indução de brotações in vitro de Dendrobium phalaenopsis Deang Suree em função do tempo de cultivo, luminosidade e BAP

The technique of in vitro micropropagation allows the production of large amounts of plants. However, some aspects of the orchid’s in vitro micropropagation are still poorly studied. This study analyzed the lighting conditions, time of cultivation and BAP concentrations on in vitro budburst of Dendrobium phalaenopsis Deang Suree. Therefore, a quantitative analysis of biometric parameters of plants grown during 90 and 180 days on ½ MS medium under different lighting conditions (18.90 mol m-2 s-1, 14.85 mol m-2 s-1, 9.45 mol m-2 s-1) and concentrations of BAP (0; 0.5; 1; 1.5; 2; 2.5 e 3 mg L-1). The best results of budburst were obtained during 180 days, under white fluorescent light (18.90 mol m-2 s-1) and using 1.5±0.1 mg L-1 of BAP.

Integrated micro-biochemical approach for phytoremediation of cadmium and lead contaminated soils using Gladiolus grandiflorus L cut flower

The potential of vermicompost, elemental sulphur, Thiobacillus thiooxidans and Pseudomonas putida for phytoremediation is well known individually but their integrated approach has not been discovered so far. The present work highlights the consideration of so far overlooked aspects of their integrated treatment by growing the ornamental plant, Gladiolus grandiflorus L in uncontaminated and sewage-contaminated soils (sulphur-deficient alluvial Entisols, pH 7.6–7.8) for phytoremediation of cadmium and lead under pot experiment. Between vermicompost and elemental sulphur, the response of vermicompost was higher towards improvement in the biometric parameters of plants, whereas the response of elemental sulphur was higher towards enhanced bioaccumulation of heavy metals under soils. The integrated treatment (T7: vermicompost 6g and elemental sulphur 0.5gkg−1 soil and co-inoculation of the plant with T. thiooxidans and P. putida) was found superior in promoting root length, plant height and dry biomass of the plant. The treatment T7 caused enhanced accumulation of Cd up to 6.96 and 6.45mgkg−1 and Pb up to 22.6 and 19.9mgkg−1 in corm and shoot, respectively at the contaminated soil. T7 showed maximum remediation efficiency of 0.46% and 0.19% and bioaccumulation factor of 2.92 and 1.21 and uptake of 6.75 and 21.4mgkg−1 dry biomass for Cd and Pb respectively in the contaminated soil. The integrated treatment T7 was found significant over the individual treatments to promote plant growth and enhance phytoremediation. Hence, authors conclude to integrate vermicompost, elemental sulphur and microbial co-inoculation for the enhanced clean-up of Cd and Pb-contaminated soils.

Cyanobacterial inoculation in rice grown under flooded and SRI modes of cultivation elicits differential effects on plant growth and nutrient dynamics

The influence of microbial inoculants on rice plants grown under two different cultivation methods – conventional (flooded) and SRI (system of rice intensification) – was evaluated in terms of nutrients’ availability in soil and their uptake by plants in a field experiment undertaken at the Indian Agricultural Research Institute, New Delhi. The treatments under conventional management recorded significantly higher values of nitrogen fixation in the soil, with Rhizobium sp. recording the highest values, although the populations of nitrogen fixers, phosphate solubilizers and cyanobacteria exhibited a 10-fold enhancement in the plots under SRI. Methane production was 50–80% lower in SRI plots inoculated with cyanobacterial-biofilmed formulations (T8–T9) and in the plots receiving recommended dose of fertilizers. The novel Anabaena-based biofilmed inoculants – T9 Anabaena–Trichoderma biofilm and T8 Anabaena–Pseudomonas biofilm, were particularly superior under both methods of cultivation ranking highest for microbiological and plant biometric parameters. The availability of P in the soil and its translocation through roots to leaves was significantly increased as a result of cyanobacterial inoculation under both modes of cultivation. The N and P content of grains were significantly higher in most of the microbial treatments in SRI mode. The treatments T5 (BF 1–4; Anabaena–Nostoc consortium), T10 (Trichoderma) and T9 (Anabaena–Trichoderma biofilm) under conventional methods recorded the highest values of grain and straw yield, which were statistically at par with those of plots with recommended dose of fertilizers. This study illustrated the benefits of both types of rice cultivation methods and the promise of cyanobacteria in improving nutrient availability, soil fertility, and crop productivity with a savings of 60kgNha−1season−1.