Assessment of the impact of climate change on the latency period of leaf rust on triticale in Poland

ABSTRACT

Disease development in plants is strongly dependent on weather conditions, with temperature playing a particularly significant role by influencing latency period duration. Using two models describing the relationship between latency period and temperature, we performed simulations aimed at predicting changes in the latency period of leaf rust (Puccina recondita f. sp. tritici) on triticale in response to expected climate change. The simulations were based on meteorological data recorded in the period 1986–2005 at locations representing 16 provinces in Poland and based on values obtained after transformation of the observed data to reflect temperature changes under four scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) according to the giss_e2_r climate model. In all scenarios, the results for the two triticale cultivars studied, Witon (vulnerable to P. recondita) and Gniewko (less susceptible), showed a threat of faster development (shorter leaf rust latency period) on triticale triggered by climate change in south-east and south-central Poland than in other regions. The results also showed an increased probability of future regional diversification of leaf rust latency period duration on vulnerable triticale cultivars, opportunities for earlier start of leaf rust epidemics on triticale in Poland and an increase in ?nal disease severity in comparison with 1986–2005.     

The effect of biostimulators on the content of crude oil and total protein in winter oilseed rape (Brassica napus L.) seeds

The objective of the study was to determine the effect of the experimental factors on the seed quality of three winter oilseed rape cultivars. The following factors were studied: I-three winter oilseed rape morphotypes: population, hybrid restored characterised by a semi-dwarf growth pattern, hybrid restored characterised by a conventional growth pattern; II-two sowing methods: a spacing of 22.5?cm, a spacing of 45.0?cm; III-four types of biostimulants: control-no biostimulants, the biostimulant Tytanit^®, Asahi^®SL, Silvit^®. Seed samples were subjected to chemical analysis to determine: crude oil, total protein and crude fibre. Natural stimulants of plant growth and development contributed to an increase in crude oil ranging from 7.4 to 9.5?g?kg^–1 d.m., on average, compared with control. The biostimulants applied did not affect total protein content which was, however, affected by meteorological conditions in individual study years as well as the genetic factor. Biostimulants increased crude fibre content compared with control.     

Synchronous fluorescence spectroscopy of edible vegetable oils. Quantification of tocopherols

The study demonstrates the application of front face and right angle synchronous fluorescence spectroscopy for the characterization of edible oils. The method enables monitoring of tocopherols, pheophytins, and other fluorescent components in edible oils. Principal component analysis of synchronous fluorescence spectra revealed sample clustering according to the type of oil. Partial least-squares regression was utilized to develop calibration models between fluorescence spectra and total tocopherol content determined by HPLC. The regression models showed a good ability to predict tocopherol content. The best fitting results were obtained for 1% v/v diluted oils and for bulk samples using the entire spectrum, yielding the regression coefficient, r, of 0.991, and root mean square error of cross-validation of approximately 8%. The results presented confirm the capabilities of the fluorescence techniques as a tool for the analysis of edible oils.     

Physiological response of culture media-grown barley (Hordeum vulgare L.) to titanium oxide nanoparticles

Since the fate of nanoparticles after their release in the environment and their possible transfer in plants and subsequent impacts is still largely unknown, this paper evaluates the potential phytotoxic effects of up to 20% w/w TiO₂ nanoparticles (nTiO₂) on barley cultivated in hydroponics and agar media. The X-ray diffraction analysis confirmed that nTiO₂ powder corresponds to anatase phase. On agar medium only high concentrations of nTiO₂ (10% and 20% w/w) induced significant inhibition of shoot growth. However, hydroponics treatment with nTiO₂ up to 1000?mg?L^?1 did not show any adverse effect on the shoot growth. In both experiments, (i) root growth inhibition effects became visible with increasing concentration of nTiO₂, (ii) plants treated with nTiO₂ showed no change in chlorophyll a and b content, even though the plants absorbed nTiO₂, (iii) weight of biomass treated with nTiO₂ was not significantly different compared to control. Therefore, we assume that transport of nTiO₂ into the aerial parts is limited due to the presence of effective mechanical or physiological barriers in roots. Overall, it appears that early root growth is a relevant indicator of potential effects of nTiO₂ exposure. Our results also indicate that synthesized nTiO₂ are not significantly toxic to the barley when applied at the concentrations used in this work, even though plants absorb titanium.     

Novel biological properties of Oenothera paradoxa defatted seed extracts: effects on metallopeptidase activity

In this study, for the first time, we used the in vitro metallopeptidase model for the identification of a potential novel activity of defatted evening primrose seed extracts. Prepared extracts of different polarity (aqueous, 60% ethanolic, isopropanolic, and 30% isopropanolic) at concentrations of 1.5-100 microg/mL exhibited a significant and dose dependent inhibition of three tested enzymes. The 50% inhibition of enzymes activity showed that aminopeptidase N (APN) was the enzyme affected to the greatest extent with IC50 at the level of 2.8 microg/mL and 2.9 microg/mL for aqueous and 30% isopropanolic extracts, respectively. The activity of neutral endopeptidase (NEP) was quite strongly inhibited by the extracts as well. The HPLC-DAD analysis and bioguided fractionation led to the identification of four active compounds: (-)-epicatechin gallate, proanthocyanidin B3, oenothein B, and penta-O-galloyl-beta-D-glucose (PGG). Oenothein B has been shown previously to inhibit metallopeptidases. The three other compounds are known to inhibit angiotensin-converting enzyme (ACE), but they have not been previously reported to inhibit the NEP and APN activity. PGG and procyanidins with different degrees of polymerization, as the dominating compounds in O. paradoxa seeds, seemed to play a role in the crude extract activity.     

Low molecular weight poly(lactic acid) microparticles for controlled release of the herbicide metazachlor: preparation, morphology, and release kinetics

The preemergence chloroacetamide herbicide metazachlor was encapsulated in biodegradable low molecular weight poly(lactic acid) micro- and submicroparticles, and its release to the water environment was investigated. Three series of particles, S, M, and L, varying in their size (from 0.6 to 8 μm) and with various initial amounts of the active agent (5%, 10%, 20%, 30% w/w) were prepared by the oil-in-water solvent evaporation technique with gelatin as biodegradable surfactant. The encapsulation efficiencies reached were about 60% and appeared to be lower for smaller particles. Generally, it was found that the rate of herbicide release decreased with increasing size of particles. After 30 days the portions of the herbicide released for its highest loading (30% w/w) were 92%, 56%, and 34% for about 0.6, 0.8, and 8 μm particles, respectively. The release rates were also lower for lower herbicide loadings. Metazachlor release from larger particles tended to be a diffusion-controlled process, while for smaller particles the kinetics was strongly influenced by an initial burst release.     

The role of Ca2+ and Na+ membrane transport in brook trout (Salvelinus fontinalis) spermatozoa motility

The role of environmental ion composition and osmolality in Ca²⁺ signaled activation was assessed in spermatozoa of brook trout Salvelinus fontinalis. Milt from ten mature males was obtained by abdominal massage. Spermatozoa motility was evaluated in 0, 100, and 300 mOsm/kg NaCl or sucrose solutions, buffered by 10 mM Tris–HCl pH 8.5. For investigation of spermatozoa reaction to external Ca²⁺ concentration, 2 mM ethylene glycol tetraacetic acid (EGTA) was added to the activation media as a calcium ions chelator. For investigation of the effect of external Na⁺ concentration in conditions of low external Ca²⁺, 100 µM amiloride was added to the EGTA-containing solutions as a Na⁺ transport blocker. Low motility was observed in sucrose (Na⁺ free) solutions containing 2 mM EGTA but not in Na⁺ solutions containing 2 mM EGTA. Addition of amiloride led to significantly increased motility (P < 0.05) compared with sucrose (Na⁺ free) solutions containing 2 mM EGTA. We conclude that Na⁺ transport in Ca²⁺-free solutions plays a regulatory role in brook trout spermatozoa activation. The influence of competitive Na⁺ and Ca²⁺ transport on the control of spermatozoa activation requires further study with respect to its application for improvement of artificial activation and storage media.     

Supplementary feeding with thermally treated cereals in common carp (<Emphasis Type="Italic">Cyprinus carpio</Emphasis> L.) pond farming and its effects on water quality,nutrient budget and zooplankton and zoobenthos assemblages

To test the influence of supplementary feeding with thermally treated cereals on nutrient budget and environmental and biotic variables, three different treatments were applied in four experimental ponds: two with thermally treated cereals, one with raw cereal and a control with no supplementary feeding. Water parameters, zooplankton and zoobenthos were analysed from May to October over two consecutive years (2012 and 2013). In addition, nitrogen and phosphorus budgets were calculated as the difference between input (feed, stocked fish) and output (harvested fish). The results showed that type of supplementary feed had no influence on water quality, aside from water transparency. Ponds with added thermally treated cereal had significantly (P < 0.05) lower turbidity and suspended solids (and increased Secchi depth) compared with control. While no significant differences were observed in zooplankton assemblages between the experimental ponds and the control, macrozoobenthos density and biomass were considerably lower in the control pond. High seasonal fluctuations resulted in significant differences in density in 2012 only. The use of thermally treated cereal led to improved carp growth and nutrient budget, with an increase in carp yield and nutrient removal per hectare of pond surface. This result is a win–win situation with 10 % lower feed conversion ratio, increased profits and lower environmental impact.     

Development of the neonatal B and T cell repertoire in swine: implications for comparative and veterinary immunology

Birth in all higher vertebrates is at the center of the critical window of development in which newborns transition from dependence on innate immunity to dependence on their own adaptive immunity, with passive maternal immunity bridging this transition. Therefore we have studied immunological development through fetal and early neonatal life. In swine, B cells appear earlier in fetal development than T cells. B cell development begins in the yolk sac at the 20th day of gestation (DG20), progresses to fetal liver at DG30 and after DG45 continues in bone marrow. The first wave of developing T cells is gammadelta cells expressing a monomorphic Vdelta rearrangement. Thereafter, alphabeta T cells predominate and at birth, at least 19 TRBV subgroups are expressed, 17 of which appear highly homologous with those in humans. In contrast to the T cell repertoire and unlike humans and mice, the porcine pre-immune VH (IGHV-D-J) repertoire is highly restricted, depending primarily on CDR3 for diversity. The V-KAPPA (IGKV-J) repertoire and apparently also the V-LAMBDA (IGLV-J) repertoire, are also restricted. Diversification of the pre-immune B cell repertoire of swine and the ability to respond to both T-dependent and T-independent antigen depends on colonization of the gut after birth in which colonizing bacteria stimulate with Toll-like receptor ligands, especially bacterial DNA. This may explain the link between repertoire diversification and the anatomical location of primary lymphoid tissue like the ileal Peyers patches. Improper development of adaptive immunity can be caused by infectious agents like the porcine reproductive and respiratory syndrome virus that causes immune dysregulation resulting in immunological injury and autoimmunity.