Mapping antixenosis genes on chromosome 6A of wheat to greenbug and to a new biotype of Russian wheat aphid

Greenbug and Russian wheat aphid (RWA) are two devastating pests of wheat. The first has a long history of new biotype emergence and recently. RWA resistance has just started to break down. Thus, it is necessary to find new sources of resistance that will broaden the genetic base against these pests in wheat. Seventy‐five doubled haploid recombinant (DHR) lines for chromosome 6A from the F₁ of the cross between “Chinese Spring’ and the “Chinese Spring (Synthetic 6A) (Triticum dicoccoides × Aegilops tauschii)” substitution line were used as a mapping population for testing resistance to greenbug biotype C and to a new strain of RWA that appeared in Argentina in 2003. A quantitative trait locus (QTL) (br antixenosis to greenbug was significantly associated with the marker loci Xgwm1009 and Xgwm1185 located in the centromere region of chromosome 6A. Another QTL which accounted for most of the antixenosis against RWA was associated with the marker loci Xgwm1291 and Xiinni1150. both located on the long arm of chromosome 6A. This is the first report of greenbug and RWA resistance genes located on chromosome 6A. It is also the first report of antixenosis against the new strain of RWA. As most of the RWA resistance genes present in released cultivars have been located in [he D‐ genome, it is highly desirable to find new sources in other genomes to combine the existing resistance genes with new sources.     

Cryopreservation of ram semen: Manual versus programmable freezing and different lengths of equilibration

The aim of our study was to examine effects of the length of semen equilibration as well as two freezing techniques on ram sperm post-thaw quality. The ejaculates of Wallachian sheep rams (n = 12) were collected by an electro-ejaculation, equilibrated in a Triladyl® (0, 2, 4, 6, and 8 h) containing glycerol and egg yolk and frozen by programmable freezing (PF) or manual freezing (MF). After thawing, sperm samples were subjected to the motility (computer-assisted sperm analysis [CASA]), viability (SYBR-14/PI), and fertilizing ability (FA) (in vitro penetration/fertilization test on bovine oocytes) assays. It was found that the equilibration of 6 h (E-6) ensured higher post-thaw sperm motility and progressive movement compared with other lengths tested, irrespective of a freezing technique. The E-6 sperm viability did not differ between PF and MF but was lower (P < 0.05) than control. Sperm FA (E-6) was similar in PF (60.44%) and MF (62%) but slightly lower than in fresh (72.8%). Our data demonstrate that the use of MF was comparable with PF, which can be applied in the field conditions without need in a piece of cost-expensive equipment, which can greatly benefit the gene bank of animal genetic resources.     

Analysis of Chlorophenols, Chlorocatechols, Chlorinated Methoxyphenols and Monoterpenes in Communal Sewage of ŁÓDŹ and in the Ner River in 1999–2000

The aim of the study was to determine phenol, chlorophenols, chlorocatechols, chlorinated methoxyphenols and monoterpenes in communal sewage that was purified by Group Purification Plant in ?ód? (Poland) and also in Ner River that is the receiver of purified sewage. The effectivity of degradation (purification) of investigeted compounds was also analysed. The compounds were concentrated on octadecyl (C 18) layers in a Baker-Separex system. Obtained extract was separated using gas chromatography (GC) and analysed by mass spectrometry (MS). In investigated samples phenol, chlorophenols, chlorocatechols, chloroguaiacols, chlorosyringols, 3,4,5-trichloroveratrole, 5,6-dichlorovaniline and several monoterpenes were determined. Performed analysis showed unsufficient effectivity of degradation of investigated compounds, particulary chlorophenols and their chlorinated derivatives. In some cases also appearance of some of the compounds (chlorinated catechols and methoxyphenols) after biodegradation (purification) proccess was observed.     

Soil Organic Matter Content and Quality in Polyfactorial Field Experiments

The polyfactorial long-term field experiments founded in 1979 exist in four different sites till the present time. The experimental design and selected variants have been described in our previous paper (Lipavsky et al. 2002). Besides of the organic carbon and nitrogen contents in soil, dry matter of the main and second products, nitrogen uptake by the main and second products presented in our previous paper (Lipavsky et al, 2002), hot water soluble carbon (C hwl ), humic substances, e.g. humic and fulvic acids have been determined in soil samples taken in autumn each year from six selected variants of organic and mineral fertilisation. The results of the hot water soluble carbon content and humic and fulvic acids contents in the air dried soil samples have been evaluated in this paper. It was shown that humic substances are rather conservative and site specific soil properties that are not much affected by the cropping and fertilisation systems. Hot water soluble carbon, on the other hand, seems to be a dynamic part of the soil organic matter.     

Impact of chlorfenvinphos, an organophosphate insecticide on human blood mononuclear cells (in vitro)

In the present study, the investigation of the effect of chlorfenvinphos (CFVF) on necrotic and apoptotic changes as well as on selected morphological and biochemical parameters in human blood mononuclear cells were investigated.We analyzed the effect of this compound on proteins damage and free-radical formation in human blood mononuclear cells. Furthermore, changes in the size (FSC-A) and granularity (SSC-A) of human blood mononuclear cells exposed to chlorfenvinphos were assessed. In order to detect apoptosis, two testes were used including analysis of YO-PRO-1 iodide/propidium iodide and Annexin V/propidium iodide staining, which revealed that chlorfenvinphos increased the number of apoptotic cells at its highest concentration of 250 μM. Chlorfenvinphos at the concentrations from 50 and 100 μM increased the size and granularity of the blood mononuclear cells, respectively. Moreover, chlorfenvinphos induced the statistically significant loss of human blood mononuclear cells viability at the concentration of 250 μM. Protein damage (the increase in carbonyl groups content) was provoked by CFVF at concentrations of 100 μM and 250 μM. Furthermore, chlorfenvinphos from relatively low concentrations of 5 μM induced reactive oxygen species formation (ROS).Conclusion: The present findings provide information that chlorfenvinphos only at 250 μM is harmful to human blood mononuclear cells, the concentration which may appear in the organism only as a result of acute or subacute poisoning. Lower concentration (5-50 μM), which caused changes in level of ROS formation can affect human organism as a result of environmental exposure.     

Chloroguaiacols Change Some Antioxidative Parameters and Affect the Activity of Glutathione S-transferase in the Leaves of Reed Canary Grass (Phalaris arudinacea)

In this work, we evaluated the effect of harmful ecotoxins, 4,5,6-trichloroguaicol (4,5,6-TCG) and tetrachloroguaiacol (TeCG), on the oxidation of the fluorescent probe dihydrorhodamine 123, the content of free phenols and the level of the total, oxidized and reduced glutathione in the leaves of reed canary grass (Phalaris arudinacea). Furthermore, the effect on the activity of guaiacol peroxidase and glutathione S-transferase was investigated. Both 4,5,6-TCG and TeCG increased the activity of guaiacol peroxidase and glutathione S-transferase, they also elevated the content of free phenols and the level of the total glutathione. A stronger effect was exerted by tetrachloroguaiacol, which strongly increased the level of the total glutathione and the content of free phenols on the 3rd and 6th day of the experiment. The activity of glutathione S-transferase was more intensively induced by trichloroguaiacol. Both 4,5,6-TCG and TeCG oxidized dihydrorodamine 123 and the effect was stronger in the presence of magnesium ions.     

Influence of Macrophages on the Rooster Spermatozoa Quality

The goal of this study was to evaluate the occurrence of macrophages in rooster semen and to investigate their impact on the spermatozoa quality. Ross 308 breeder males (n = 30) with no evidence of genital tract infections were used to determine the concentration of macrophages using fluorescently conjugated acetylated low‐density lipoprotein (AcLDL). Subsequently, the roosters were divided into two groups on the basis of semen macrophage concentration, and semen quality was compared in two heterospermic samples. We applied computer‐assisted semen analysis (CASA) system to determine motility parameters. Fluorescence microscopy and flow cytometry were used to evaluate occurrence of apoptotic and dead spermatozoa. Spermatozoa fertility potential was examined after intravaginal artificial insemination of hens. Eighteen roosters (control group) contained 0.2–3% of macrophages within spermatozoa population and ten roosters (macrophage group) had 10–15% of macrophages. Males from macrophage group had lower (p < 0.05) motility parameters (total and progressive movement, velocity curved line) and increased concentration of dead spermatozoa detected by flow cytometry and fluorescence microscopy (p < 0.001 and p ? 0.05, respectively). Differences (p < 0.05) between fluorescent microscopy and flow cytometry in results on spermatozoa apoptosis and viability were observed. No significant difference was found between groups in fertility of spermatozoa. In conclusion, the higher presence of macrophages in rooster semen may have a negative effect on some parameters of rooster spermatozoa evaluated in vitro. Furthermore, our study suggests that flow cytometry allows more precise examination of spermatozoa viability and apoptosis in a very short time compared with the fluorescent microscopy.     

Field leaching of pesticides at five test sites in Hawaii: modeling flow and transport

BACKGROUND: Physically based tier‐II models may serve as possible alternatives to expensive field and laboratory leaching experiments required for pesticide approval and registration. The objective of this study was to predict pesticide fate and transport at five different sites in Hawaii using data from an earlier field leaching experiment and a one‐dimensional tier‐II model. As the predicted concentration profiles of pesticides did not provide close agreement with data, inverse modeling was used to obtain adequate reactive transport parameters. The estimated transport parameters of pesticides were also utilized in a tier‐I model, which is currently used by the state authorities to evaluate the relative leaching potential. RESULTS: Water flow in soil profiles was simulated by the tier‐II model with acceptable accuracy at all experimental sites. The observed concentration profiles and center of mass depths predicted by the tier‐II simulations based on optimized transport parameters provided better agreements than did the non‐optimized parameters. With optimized parameters, the tier‐I model also delivered results consistent with observed pesticide center of mass depths. CONCLUSION: Tier‐II numerical modeling helped to identify relevant transport processes in field leaching of pesticides. The process‐based modeling of water flow and pesticide transport, coupled with the inverse procedure, can contribute significantly to the evaluation of chemical leaching in Hawaii soils. Copyright © 2011 Society of Chemical Industry     

Identification of wheat chromosomes involved with different types of resistance against greenbug (Schizaphis graminum, Rond.) and the Russian wheat aphid (Diuraphis noxia, Mordvilko)

Two sets of intervarietal chromosome substitution lines in the recipient,susceptible cultivar ‘Chinese Spring’ were screened to identify the wheat chromosomes involved with antixenosis, antibiosis and tolerance resistance to greenbug and Russian wheat aphid. The amphiploid ‘Synthetic’ and the cultivar ‘Hope’ were the donor parents. Antixenosis, antibiosis and tolerance were evaluated with conventional tests in controlled environmental conditions using a clone of greenbug biotype C and a clone of RWA collected on wheat. Antixenosis against greenbug was accounted for by several chromosomes in both sets of substitution lines with chromosome 2B contributing the highest level of this type of resistance. The highest levels of antixenosis against RWA were associated with the group of chromosomes 7 of the substitutions CS/Syn set and the chromosome substitutions 2B, 6A and 7D of the CS/Hope set. Antibiosis against both aphids species was accounted for by several different chromosomes. The highest levels of antibiosis for most of RWA resistance traits were recorded from the 1B substitution line of the CS/Hope set. More than one gene appears to determine antibiosis. Tolerance to both greenbug and the RWA was significantly associated with chromosomes 1A,1D, and 6D in the CS/Syn set of substitutions. These lines showed enhanced plant growth under aphid infestation. The highest levels of antixenosis, antibiosis and tolerance against the two aphid species occurred mostly in different substitution lines. Consequently, the different types of resistance for both pests seem to be partially independent. Since different genes seem to be involved in at least several traits of the resistance categories against the two aphid species, such genes could be combined in new cultivars of wheat to broaden their genetic base of resistance against the greenbug and the RWA. This revised version was published online in July 2006 with corrections to the Cover Date.