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Pistacia vera L., whose edible fruit is the pistachio, is an economically important crop. It is cultivated worldwide and over 50 different varieties have been described attending to morphological and phenological characteristics. The selection of a suitable cultivar may affect the profitability of the orchards, and thus requires careful consideration for any given region. The type and concentration of nutrients taken up by the plant affect its development and eventually the quality and quantity of the fruits. It is a matter of discussion whether all varieties have the same capacity to absorb nutrients. In order to clarify this aspect, in this study the efficiency of nutrient uptake has been assessed for five pistachio varieties: three males (M38, G1, and Mateur), and two females (Batoury, and Joley), by measuring the concentration of 30 chemical elements in leaves by Inductively Coupled Plasma (ICP) and C/N micro-elemental analyses. Data were subjected to a non-parametric Friedman test, using a series of Wilcoxon Rank Sum test with a Bonferroni correction as post hocs. Our findings demonstrate that all these varieties have an equal uptake capacity for Al, Cr, Cu, K, Li, Mn, Ni, Pb, S, Sr, Ti, Tl, Zn, N, B, Fe, Mg, Na, and V. No differences related to the gender of the plants were detected. Only Mateur exhibited significantly higher levels of Ca and lower levels of C. Stock plants from an experimental plot were used as material. These plants are not used for productive purposes, and flowering and fruiting are partially restricted by removing potential nutrient-demanding structures. These findings support the contention that the presence/absence of such organs has more influence on the nutrient uptake than does the variety itself.
A pot culture was carried out with Oryza sativa L. vari-Co-39, to investigate the effects of supplementary calcium chloride on plants grown at NaCl (50mM) concentration. Treatments were: (1) Control: nutrient solution alone (C); (2) nutrient solution plus 50mM sodium chloride (NaCl); (3) nutrient solution plus 10mM calcium chloride (CaCl2); (4) nutrient solution plus 15mM calcium chloride (CaCl2); (5) nutrient solution and 50 mM NaCl plus supplementary 10 mM CaCl2 (NaCl + CaCl2); and (6) 50 mM NaCl plus additional mixture of 15 mM CaCl2 in nutrient solution (NaCl + CaCl2). The plants grown under salt stress produced low dry weight and relative water content than those grown in standard nutrient solution and in CaCl2 alone. Supplemental calcium chloride added to nutrient solution containing salt significantly improved growth and relative water content. Membrane permeability increased with high NaCl application and these increases in root membrane permeability were decreased with supplementary Ca. The concentration of chloride (Cl) increases highly for all treatments. Sodium (Na) concentration in plant tissues increased in both shoots and roots at high NaCl treatment. Application of supplementary Ca lowered Na concentration. Concentrations of Ca. K and N were at deficient ranges in the plants grown at high NaCl levels and these deficiencies were corrected by supplementary Ca. The ameliorating effect of Ca on growth and physiological variables could reduce the negative effect of salinity of Oryza sativa L., plants.
В период 1981-1983 гг. был проведен опыт охватывающий 7 удобрительных вариантов (NPK, N, Р, K, NK и PK), в которых применяли удобрение типичное для сосудных опытов, т.е. (в чистом элементе): N - 1 г, P₂O₅ - 0,8 г, K₂O - 1,2 на сосуд и в двухкратно высших количествах. Контрольный вариант оставался без удобрения. Установлено ограничивающее действие минерального удобрения (за исключением исключительно фосфорного удобрения) на всходы галинсого Масса надземных частей галинсого повышалась в гораздо высшей степени под влиянием азота, чем фосфора и калия. Внесение двойных доз удобрений приводило к снижению массы надземных частей на 31%, а корней на 27%. Усваивание основных питательных элементов галинсогой зависело от примененных удобрений (особенно калийное удобрение приводило к повышению содержания K₂O). Также количество питательных элементов в почве после уборки галинсого показывало тесную связь с видом и уровнем удобрения.
The study, carried out in 2012-2013, intended to determine effects of different cultivation systems on the uptake and content of macronutrients (nitrogen, phosphorus, potassium, magnesium, calcium and sodium) in sugar beets at the technological maturity stage. A conventional tillage system (SO) was compared to simplified technologies of soil cultivation. The following conservation tillage systems were analyzed: (2) tillage to a depth of 35 cm and sowing into stubble mulch (MS35); (3) shallow tillage to a depth of 15 cm and sowing into stubble mulch (MS15); (4) tillage to a depth of 15 cm and sowing into white mustard mulch; (5) strip-till on stubble mulch to a depth of 25 cm and instantaneous beet seed sowing (STS); (6) strip-till to a depth of 25 cm on white mustard mulch and instantaneous beet seed sowing (STG). Mineral nutrient concentrations in beets varied depending on the cultivation system applied and the plant organ analyzed. The experimental factor significantly differentiated the content of P, K, Ca, Mg and Na in both beet leaves and roots, having no effect on the nitrogen content. When compared to the conventional tillage system, a decreasing trend for phosphorus and calcium in beet leaves and a significant increase of sodium both in beet leaves and roots was observed in the simplified cultivation systems. Cultivation simplifications provided some equivocal evidence implicating differences in the nutrient content between the study years. The analysis of correlations between root yields and the total accumulation of nutrients indicated significant relationships for N, P, K, Ca, Mg only in the conventional tillage system and in the treatment with 35 cm deep tillage (soil ripping) along with sowing into stubble mulch (MS35). In the other treatments, strong relationships were observed only for individual nutrients.
В сосудном опыте проведенном в 1981-1983 гг. исследовали влияние почвенной влаги дифференцированной до 40, 60, 80 и 100% капиллярной влагоемкости, на рост галинсоги мелкоцветковой (Galinsoga parviflorа Cav.). Галинсога появлялась наиболее скоро и массово в максимально влажном варианте (33 растения на сосуд), а наиболее медленно в самом сухом варианте (15 растений на сосуд). Для дальнейшего роста галинсоги наиболее благоприятной оказалась влажность почвы в пределах 60- 80%. По мере повышения увлажнения субстрата растения усваивали больше P₂O₅ и K₂O, а меньше азота и СаО. После уборки растений наиболее K₂O и СаО осталось в самой сухой, в азота - в самой влажной почве.
This study was conducted to evaluate the effects of higher conductivity of nutrient solution created by nitrate or chloride salts of potassium and calcium on growth characteristics of pepper plants (Capsicum annuum var annuum) during four months of growth period. Two EC5 and EC8 dS/m of Hoagland nutrient solutions were prepared using various salt combinations, namely: KCl + CaCl2, KNO3 + CaNO3, and KNO3 + CaNO3 + NaCl. Hoagland nutrient solution with EC 1.8 dS/m served as a control. Higher conductivity treatments had different effects on pepper plant growth. The most significant reduction in growth parameters of plant height, shoot fresh weight, fruit yield and nutrients uptake was in plants treated with KCl + CaCl2 particularly at EC8. Application of KNO3 + CaNO3 particularly at EC5, showed no difference as compared to the control regarding many growth parameters. Application of KNO3 + CaNO3 at EC5 resulted in higher shoot fresh weight compared to the control. All salinity treatments, except from KNO3 + CaNO3 at EC5, reduced the fruit yield compared to the control. Treatments of KCl + CaCl2 and KNO3 + CaNO3 + NaCl particularly at EC8 of nutrient solution, resulted in higher leaf proline concentration, catalase and peroxidase enzymes activity compared to the control. Other conductivity treatments showed no difference in catalase or peroxidase enzymes activities. Significantly the lowest amount of leaf N, K, Mg and Ca was in KCl + CaCl2 at EC8. On the other hand, the highest leaf macronutrient concentrations were in KNO3 + CaNO3 at EC5 and/or EC8 that showed only higher leaf N and Ca values compared to the control. Leaf micronutrient concentrations were the highest in KNO3 + CaNO3 at EC5 that generally showed no difference with control plants. However, application of KCl + CaCl2 particularly at EC8 and to less extent KNO3 + CaNO3 + NaCl at EC8, reduced the leaf micronutrient concentrations. Application of KNO3 + CaNO3 at EC5 increased and KCl + CaCl2 or KNO3 + CaNO3 + NaCl at EC8 decreased the leaf Fe concentration compared to control plants.
Biofertilizers have been used as sources to improve plant nutrients in sustainable agriculture. Biofertilizers are low cost, renewable sources of plant nutrients which supplement chemical fertilizers. Mycorrhizal fungi are a major component of agricultural natural resources and members of kingdom fungi. The term ‘mycorrhiza’ is derived from Greek word which means ‘fungus root’. Earthen pot experiments were carried out to study the inoculation effect of Arbuscular Mycorrhizal (AM) fungi (Glomus mossease), Azospirillium brasilense and PSB on plant height, dry weight of root and shoot, per cent root colonization, spore number, P and N uptake. Experimental pots were filled with 4 kegs of sterilized soil and maintained in green house at 25-30 °C temperature. Single inoculation of AM fungi and combined inoculation of AM fungi with Azospirillium brasilense or PSB was found to be moderately increased in all the growth parameters. However triple inoculation of AM fungi, Azospirillium brasilense and PSB was found to have highest growth parameters.
Woody plants grown near the roads are force-fed by salt and this has negative effect on their growth and decorative value. The aim of the presented study was to investigate the effects of salinity on growth and nutrient composition of four trees species often planted along the roads and streets in Poland. Two years old seedlings (bare root) of four tree species: Acer negundo, A. platanoides, Quercus robur and Tilia cordata were potted and grown outside under four soil salinity levels maintained by drenching plants with tap water containing 0.25, 0.5, 1.5, and 3.3g NaCl/L H2O. Plant height, soil samples for electrical conductivity (EC) and pH determination as well as leaf samples for macroelements (N, P, K, Ca, Mg) content evaluation were collected after each growing season of two years of experiment. Electrical conductivity of the growing medium varied insignificantly between species, but salt concentration in the growing medium was distinctly higher in the upper than in the bottom part. Soil salinity had strong but variable effect on plant growth during the experiment. Only Acer negundo growth was not affected even by the highest concentration of NaCl solution. With increasing salinity of growing medium more Na+ was taken by all species but the biggest amount of sodium ions was accumulated in the leaves of Tilia cordata, while the lowest in Acer negundo. Than potassium ions content decreased with increasing medium salinity only in the leaves of Quercus robur and Tilia cordata. In the leaves of Acer platanoides and Tilia cordata calcium concentration was decreased at increased salinity, in two other tested species amount of Ca2+ in the leaves was elevated. The main conclusion that can be drown is that Acer negundo is highly tolerant to salinity stress while Acer platanoides was the most sensitive among tested species.
The effects were investigated of phosphorus nutrition and AMF inoculation on nutritional status, growth, and flowering of China aster (Callistephus chinensis (L.) Nees) ‘Milady’ during cultivation on ebb-and-flow benches. Two P treatments of 8.68 and 43.40 mgxdm-3 were applied. One month after inoculation the roots of inoculated plants were infected by mycorrhizal fungi. The control plants had no root infection. The mycorrhizal fungal colonization in plants that were fertilized at 8.68 and 43.40 mg x dm-3 P was 67% and 60% respectively. Slightly increased P content was detected in leaves of mycorrhizal plants grown under low P level. Mycorrhization did not affect leaf P content of plants grown in high P level. Increased Mg content was measured in leaves of mycorrhizal plants grown under both P levels. Mycorrhizal and nonmycorrhizal plants did not differ with regard to leaf N, K, and Ca contents. P nutrition did not also affect the contents of these elements in leaf tissue. Mycorrhization decreased the pH and lowered salt accumulation in growing media. Significantly lower shoot biomass, plant height, shoot number were recorded in all plants inoculated with AMF. Mycorrhization also delayed flowering of China aster; the high P level slightly accelerated it. Mycorrhizal plants had fewer flower buds and flowers than nonmycorrhizal ones. The high P level increased the number of flowers of nonmycorrhizal plants only.
The aim of a study was to determine the nutrient and water uptake by tomato plant grown in three independent systems of the nutrient film technique (NFT), provided with the nutrient solutions containing different levels of sulphates: I – 200, II – 400, i III – 600 mg dm⁻³. Nutrient and water uptake depended mainly on stages of plant maturity, and in a less degree on the concentration of sulphates in the solution. Average daily uptake by single plant was (mg): nitrogen – 131.4; phosphorus – 31.6; potassium – 229.6; calcium – 100.7; magnesium –23.2. Average daily uptake of water was 1084 cm³.
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