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21.
Lettuce yield and root activity as affected by an ion exchange substrate and mineral nutrition level
The study involved investigating the effect of ion exchange substrate (IES) addition to a nutrient solution (2% or 5% v/v) on the yield and root parameters of butterhead lettuce (Lactuca sativa L. cv. “Justyna”) under the conditions of basic (1.5-times concentrated Hoagland solution, electrical conductivity, EC 2.41–2.47 dS m?1), and intensive (3-times concentrated Hoagland solution, EC 6.85–7.30 dS m?1) mineral nutrition level. Regardless of the mineral nutrition level, both experimental additions of IES significantly increased the yield and elevated the volume, as well as the whole (WRA) and the active (ARA) adsorptive surface area of roots. It was confirmed that the substrate did not cause salt stress. Additionally, it was revealed that the substrate constitutes a beneficial component of lettuce in non-salinized (basic) or salinized (intensive mineral nutrition level) environment and that the 2% dose was more favorable than 5% dose. 相似文献
22.
Daniel Moreno-Fernández Fernando Montes Mariola Sánchez-González Francisco J. Gordo Isabel Cañellas 《European Journal of Forest Research》2018,137(1):17-27
The dynamics of mixed stands are more complex and less studied than those of monospecific stands. The objective of this work was to analyze the variables involved in seedling occurrence and seedling survival in mixed stands of Pinus pinaster and P. pinea in Mediterranean areas. From 2011 to 2016, regeneration of both species was monitored at two sites located in Central Spain. We installed 72 regeneration plots where seedling dynamics were monitored. All the trees in the study areas were measured and mapped. Additionally, we took hemispherical photographs in each regeneration plot. The average density of P. pinea seedlings over the study period was almost 20 times larger than that of P. pinaster. Our results indicate that the seedlings of both species grow under moderate light conditions. In addition, we found that the occurrence of seedlings of both species was related to the structure of the stand. P. pinea seedlings grew where the density and size of P. pinaster trees were low and where P. pinea trees provided moderately sheltered conditions, whereas the number of P. pinaster seedlings was related to under intermediate densities of P. pinaster trees. Furthermore, seedling survival was positively associated with age of the seedlings and negatively with the August average maximum temperature. The temporal continuity of mixed stands of P. pinea and P. pinaster in the study area is compromised by the observed lack of regeneration of P. pinaster. 相似文献
23.
Mariola Staniak Jolanta Bojarszczuk Jerzy Księżak 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(3):255-263
Crop performance and yield are the results of genotypic expression as modulated by continuous interaction with the environment. Among environmental factors, water is globally one of the most limiting for crop production. Water resources in the world are steadily diminishing and in many areas, including Poland, more frequent periods of drought are being observed. The aim of the study was to compare the yields and gas exchange parameters of Festulolium hybrid (Festulolium braunii (K. Richt) A. Camus) and alfalfa (Medicago?×?varia T. Martyn) under different levels of soil moisture (well-watered conditions and drought stress) and cultivation method (pure stand and mixture). The study has shown that all the measured parameters were affected by drought stress. Net photosynthetic rate, transpiration rate, stomatal conductance and dry mass yield were significantly lower under drought stress than under well-watered conditions in all treatment types. Alfalfa grown in a pure sowing showed the strongest reaction to stress, while hybrid Festulolium grown in mixture showed the weakest. It was also found that under stress, grass assimilated CO2 and evaporated water much more intensively in mixture cultivation than in pure sowing. Higher water use efficiency (WUE) was observed in alfalfa and Festulolium growing in mixture only in the first year of the study. 相似文献
24.
25.
Grzegorz J. Dietrich Mariola Dietrich Piotr Hliwa Robert Stabinski Joanna Nynca Aneta Andronowska Andrzej Ciereszko 《Fish physiology and biochemistry》2010,36(3):419-425
The objective of this study was to describe the morphometry and motility parameters of vendace (Coregonus albula) spermatozoa. Morphometric parameters of vendace sperm head and tail were of values similar to rainbow trout. The effects
of pH, sodium, potassium and calcium ion concentrations on computer-assisted sperm analysis (CASA) sperm motility characteristics
were tested. Vendace sperm was motile in a wide pH range of 6.0–10.5 with the optimum pH established at 9.0. Increases in
potassium and calcium ions caused decreases in the percentage of motile sperm. The CASA parameters and erratic sperm movement
pattern of vendace spermatozoa were similar to whitefish (C. lavaretus) sperm motility, suggesting that there is a coregonid-specific sperm motility pattern. 相似文献
26.
Mariola Sánchez-González Isabel Cañellas Gregorio Montero 《European Journal of Forest Research》2008,127(3):173-182
A cork growth model for Spanish cork oak forests was developed using data from 432 cork samples. Ten dynamic equations derived
from the generalised algebraic difference approach (GADA) were considered for analysis, and both numerical and graphical methods
were used to compare alternative models. All of the equations are base-age invariant and directly estimate accumulated cork
thickness in complete years at any moment of the cork rotation. The fittings were done using the nested iterative method of
the stochastic regression approach. The GADA formulation derived by Krumland and Eng (2005) from the Richards model by considering a
1 and a
3 as related to site productivity was finally selected. The cork growth model developed in this study allows the total accumulated
cork thickness in complete years to be estimated in the fourth year of cork rotation with close to 80% reliability for any
debarking period, increasing to nearly 90% from the eighth year onwards. 相似文献
27.
Mariola Wojtczak Grzegorz J. Dietrich Mariola S&#x;owi&#x;ska Stefan Dobosz Henryk Ku
mi&#x;ski Andrzej Ciereszko 《Aquaculture (Amsterdam, Netherlands)》2007,270(1-4):259-264
All evidence to date suggest that sperm motility is the primary determinant of fertilization success in externally fertilizing fish species. Ovarian fluid, which comprises 10–30% of the total egg volume in salmonids, enhances sperm motility with respect to swimming speed, trajectory and the duration of movement. It was recently demonstrated that there is individual variability in sperm motility enhancing potential of ovarian fluid of particular females. In the present study we examined the effect of particular ovarian fluids collected from 31 females on the sperm motility parameters of one male of rainbow trout (Oncorhynchus mykiss) using computer-assisted sperm analysis (CASA). During our experiment we also monitored the pH of ovarian fluid. We found that particular fluids differed in the ability to activate spermatozoa; sperm remained immotile in four fluids and exhibited 50–100% motility in 27 samples. The percentage of motile sperm, velocity and duration of movement positively correlated with ovarian fluid pH (r2 = 0.34–0.62). These data strongly suggest that the pH of the ovarian fluid is the primary determinant of sperm motility in rainbow trout under natural conditions of fertilization. 相似文献
28.
Dietrich MA Nynca J Westfalewicz B Karol H Ciereszko A 《Fish physiology and biochemistry》2011,37(3):447-452
Calcium ions play an important role in the activation of fish sperm movement. The mechanism of their binding in semen is still
unknown. The goal of this study was the development of a method for identifying calcium-binding proteins in fish seminal plasma.
Two methods of calcium-binding proteins detection were tested with the use of Quin2 and Stains-all dyes. The first method
was useful for the identification of calcium-binding proteins of fish seminal plasma. It consisted of proteins separation
using SDS–PAGE, transfer on PVDF membrane, incubation with CaCl2, staining with Quin2 and illumination with UV light to reveal calcium-binding protein bands. Using Quin2 allowed the detection
of calcium-binding proteins with low and high molecular weight. Electrophoretic species-specific profiles of calcium-binding
proteins were identified in the seminal plasma of carp, whitefish, roach, brook trout, brown trout and rainbow trout. Staining
of calcium-binding proteins with Quin2 is a quick and safe method, allowing the identification of calcium-binding proteins
in fish semen. 相似文献
29.
Maria Hurtado Santiago Vilanova Mariola Plazas Pietro Gramazio Isabel Andújar F. Javier Herraiz Angel Castro Jaime Prohens 《Genetic Resources and Crop Evolution》2014,61(4):787-795
We have used the Almagro pickling eggplant landrace as a model for the enhancement of a local vegetable landrace. The programme has included characterization, selection, and breeding activities. Considerable intra-landrace diversity has been found for morphological traits and molecular markers. Characteristic morphological traits have allowed its registration as conservation variety. Also, universal and specific simple sequence repeat markers have been found for the Almagro landrace. The chemical characterization revealed that Almagro eggplant has a high content in bioactive phenolics. Organoleptic tests revealed that pickles produced with Almagro eggplant are superior to those of the related Andalusian landrace. The selection programme has led to the development of a pure line with increased yield and reduced fruit calyx prickliness. A participatory breeding programme, in which selection is made by farmers in their own field, has been initiated to introduce the no-prickles trait from three other varieties in the genetic background of the Almagro eggplant. The results of the programmes show that plants with the Almagro eggplant ideotype and with reduced prickliness can be selected in the backcross generations. As a result of the enhancement programme the acreage and total production of Almagro eggplant has tripled in the last decade. 相似文献
30.
Mariola Chomczynska Siergiej Pristavko Vladimir Soldatov Henryk Wasag 《植物养料与土壤学杂志》2014,177(3):438-442
The effect of 2% (v/v) addition of ion exchange substrate to a sandy soil on the growth of Dactylis glomerata L., used as a test species, was studied. Four different exchange additives having pH values in the range 4.45–7.14 were evaluated in pot experiments. These additives were prepared as mixtures of monoionic forms of a strong acid cation exchanger and a weak base anion exchanger, loaded with nutrient ions. The additions of the ion exchange substrates to the sand affected plant growth advantageously, increasing the total dry biomass 3.8– 8.5 times. The most efficient additive appeared to be the substrate with the lowest pH because it contained the largest stock of nutrient elements. The excessive acidity of the additive was spontaneously neutralized in the mixtures with sand due to reaction of the acid excess with carbonates present in the natural sandy soil. 相似文献