Discontinuous gas exchange (DGE) is the main (23 individuals) breathing mode in resting adult Platynus assimilis. Few of the beetles tested (13 individuals) displayed a pattern of cyclic gas exchange or CGE. The burst of CO2 release in DGE and CGE was always accompanied by abdominal pumping (active ventilation or V). Seven individuals displayed a pattern of continuous respiration, characterized by regular abdominal pumping. Resting metabolic rate (RMR) in continuously breathing beetles was higher than in those using DGE and CGE. After treatment with sub-lethal doses of alpha-cypermethrin DGE ceased. Treated beetles were characterized by continuous pumping and almost regular periods of activity. RMR increased significantly after treatment with a pyrethroid., Irja Kivimägi ... [et al.]., and Obsahuje seznam literatury
The aim of this study was to characterize the key physiological aspects of three sugarcane cultivars (RB92579, RB867515 and RB872552) under biological nitrogen fixation (BNF). Plants were generated in tubes containing aseptic substrates and these plants were transferred to pots containing washed sand, but watered with a mineral fertilizer, and inoculated with a mixture of five diazotrophic bacteria three times at seven-day intervals. Under BNF, all of the cultivars contained half of their total leaf nitrogen content and 50% less shoot dry mass. The leaves of plants under BNF showed approximately 65% less of the total protein content (TP). The
gas-exchange control plants had twice the CO2 assimilation rates than the BNF plants. The activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX) was increased in all cultivars under BNF when compared with the control; thus, the content of hydrogen peroxide (H2O2) was also increased in these plants. The results of this study indicate that after acclimatization, the inoculation of young plants from tissue culture with diazotrophic bacteria could supply approximately 50% of their nitrogen requirement., C. D. Medeiros ... [et al.]., and Obsahuje bibliografii
The response of some photosynthetic parameters (CO2 assimilation, transpiration rate, stomatal conductance, intercellular CO2 concentration, water-use efficiency, and chlorophyll content), shoot development, and the morphological features of the root system to differentiated conditions of nitrogen supply was tested in festulolium (Festulolium braunii K. Richert A. Camus) varieties (Felopa and Sulino). Nitrogen fertilization with no nitrogen added
[0 g(N)], single dosage [0.23 g(N)], and double dosage [0.46 g(N)] per pot and per year was applied. Lack of nitrogen resulted in formation of longer and finer roots and lowered chlorophyll content, CO₂ assimilation, and water-use efficiency, resulting in lower dry matter accumulation. Application of both dosages of nitrogen resulted in improved aboveground features, while root features were enhanced without nitrogen fertilization. Dependence between physiological parameters and morphological traits was significant and positively correlated in the case of the aboveground parts of plants and negatively correlated to the belowground parts., G. Mastalerczuk, B. Borawska-Jarmułowicz, H. M. Kalaji, P. Dąbrowski, J. Paderewski., and Obsahuje bibliografii
We studied water relations and gas exchange in six almond genotypes grafted on GF677 in response to withholding irrigation for 14 days and a subsequent 10-day rehydration period. The responses to drought stress significantly differed in the almond genotypes; the tolerant plants were distinguished and monitored. Leaf relative water content (RWC) decreased by more than 23%, leaf water potential dropped to less than -4.3 MPa, and electrolyte leakage increased to 43% in dehydration-sensitive genotypes. Photosynthesis (PN) and stomatal conductance (gs) of drought-sensitive genotypes were significantly reduced by 70% and 97% in response to water deficiency. Water stress significantly enhanced wateruse efficiency up to 10 folds in drought-tolerant almonds. The difference between leaf temperature and its surrounding air temperature (ΔT) increased significantly to more than 187% under water stress in drought-tolerant genotypes. In addition, the reduction in the g s and further ability to preserve RWC were involved probably in drought-tolerance mechanism in almond. Negative significant correlations were found between ΔT, PN, and gs. Based on the correlations, we suggested that ΔT could be used as a simple measurement for monitoring water stress development in the irrigation management of almond orchards. In conclusion, ‘Supernova’ and the Iranian genotypes ‘6-8’ and ‘B-124’, were found to be more droughttolerant compared with other genotypes in this experiment., S. Karimi, A. Yadollahi, K. Arzani, A. Imani, M. Aghaalikhani., and Obsahuje bibliografii
In this work, photosystem II (PSII) photochemistry, leaf water potential, and pigment contents of male and female Pistacia lentiscus L. were investigated during a seasonal cycle at three different, arid locations: superior semiarid, inferior semiarid, and arid. The results showed that the gender, season, and the site conditions interacted to influence the quantum yield and pigment contents in P. lentiscus. Predawn leaf water status was determined only by the site and season. The annual patterns of PSII maximum quantum efficiency (Fv/Fm) were characterized by a suboptimal activity during the winter, especially, populations with the more negative water potential exhibited a lower chlorophyll (Chl) a content and chronic photoinhibition irrespective of a gender. We also demonstrated that both photochemical or nonphotochemical mechanisms were involved to avoid the photoinhibition and both of them depended on the season. This plasticity of photosynthetic machinery was accompanied by changes in carotenoids and Chl balance. In the spring, the female Fv/Fm ratio was significantly higher than in male individuals, when the sexual dimorphism occurred during the fruiting stage, regardless of site conditions. P. lentiscus sex-ratio in Mediterranean areas, where precipitations exceeded 500 mm, was potentially female-biased. Among the fluorescence parameters investigated, nonphotochemical quenching coefficient appeared as the most useful one and a correlation was found between Chl a content and Fv/Fm. These results suggest that functional ecology studies would be possible on a large scale through light reflectance analysis. and S. Ait Said ... [et al.].
Coccidiosis is a parasitic disease caused by protists (apicomplexans) of the genus Eimeria Schneider, 1875 and is considered to be the most important disease faced by rabbit breeders due to its high morbidity. In the present study, the antioxidant status and changes in apoptosis and in the expression of some genes were quantified in rabbits' ilea following infection with Eimeria intestinalis Cheissin, 1948. Rabbits, orally infected with 1 × 105 sporulated oocysts of E. intestinalis, started to shed oocysts in their faeces on 8 days post infection (dpi) and reached maximum excretion on 10 dpi, with approximately 5 million oocysts. This was accompanied by a significant decrease in the live body weight of infected rabbits. Also, malondialdehyde and nitric oxide were significantly increased while catalase and glutathione were significantly decreased in the ileum tissues of the infected rabbits. In addition, a significant increase was observed in the percentages of apoptotic cells in the ilea of the infected rabbits. Furthermore, interleukin-1β and interleukin-2 mRNA levels were significantly down-regulated and mRNA levels of interleukin-6, interferon gamma and inducible nitric oxide synthase were significantly up-regulated, while those of C-reactive protein remained unchanged. We conclude that infection with E. intestinalis induces oxidative stress, a significant increase in the percentage of apoptotic cells and a diverse and robust Th1 and Th1-related cytokine response in the ileum tissues., Heba M. Abdel-Haleem, Shawky M. Aboelhadid, Thabet Sakran, Gamal El-Shahawy, Huda El-Fayoumi, Saleh Al-Quraishy, Abdel-Azeem S. Abdel-Baki., and Obsahuje bibliografii
Silk production quantity is the most economically important characteristic of the domesticated silkworm moth, Bombyx mori. It is controlled by multiple loci. The cocoon and silk production quantity of silkworm strains Jingsong and Lan10 have significantly diverged. A backcross population (BC1) was bred using Jingsong and Lan10 as parents to identify quantitative trait loci (QTLs) for silk quality. In this research, a genetic linkage map of the silkworm was constructed using the BC1 mapping population. The map contained 85 sequence-tagged site markers, 80 simple sequence repeat markers, and 16 single nucleotide polymorphisms. A linkage map was constructed from the data, which consisted of 181 markers distributed over 28 expected linkage groups and spans 2147.1 cM in total length. Fourteen QTLs were detected for cocoon filament length, whole cocoon weight, pupae weight, filament weight, and cocoon shell weight. The 14 QTLs were distributed in 5 linkage groups (linkage groups 1, 14, 18, 23 and 25) based on the constructed linkage map. In addition, five QTLs, which had the highest logarithm (base 10) of odds (LOD) values, were located on the first chromosome, three of which located at the same region in linkage group 1. These results represent an important foundation for the map-based cloning of QTLs and marker-assisted selection for improving the silk quality of economically important silkworm strains., Bing Li ... [et al.]., and Obsahuje seznam literatury
The genetic basis of stomatal conductance (gs), net photosynthetic rate (PN), and transpiration rate (E) was explored by using a wheat doubled haploid population from a cross of Hanxuan10 and Lumai 14. The above three traits were evaluated in wheat flag leaves at 10, 20, 30 days after anthesis under drought stress (DS) and well-watered (WW), and quantitative trait loci (QTL) were analyzed. Expression of the traits during the grain filling stage showed downward trends under both conditions, but expression of three phenotypes were stronger under WW than those under DS. Extremely significant positive correlations were established among the traits at all growth stages under both conditions. A total of 18 additive QTLs for those traits were identified on 10 chromosomes. Among them, two batches of nine additive QTLs were associated with the target traits under DS and WW, respectively. Two additive QTLs for gs and E, two for gs and PN, six for gs, PN, and E clustered at the same or near the region (colocation) of chromosomes 4A, 2B, and 7B, respectively. This provided genetic basis for close phenotype correlations among gs, PN, and E. Furthermore, QTLs for gs, PN, and E near Xgwm577 and Xgwm611 located on 7B chromosome were linked to previously reported QTLs regulating a SPAD value and the chlorophyll a/b ratio under dark-induced condition. This finding indicated that these QTLs on 7B chromosome might be involved in the process of wheat leaf senescence., S. G. Wang, S. S. Jia, D. Z. Sun, H. Y. Wang, F. F. Dong, H. X. Ma, R. L. Jing, G. Ma., and Obsahuje bibliografii
The utility of inter simple sequence repeat-PCR (ISSR-PCR) assay in the genetic characterisation and elucidation of the phylogenetic relationship of different microsporidian isolates infecting tropical tasar silkworm, Antheraea mylitta Drury, is demonstrated. A total of 22 different microsporidians collected from the diseased tasar silkworms from Jharkhand state of India were analysed using morphological characters and ISSR-PCR. Observations spores under phase contrast microscope revealed oval to elongate in shape with length ranging from 3.8 μm to 5.1 μm and width from 2.6 μm to 3.3 μm. All the microsporidian isolates except MIJ-1gC showed gonadal infection and transovarial transmission in infected tasar silkworms. Fourteen out of 20 ISSR primers tested generated reproducible profiles and yielded a total of 281 fragments, of which 273 were polymorphic (97%). The degree of banding pattern was used to evaluate genetic distances and for phylogenetic analysis. The results demonstrated that ISSR analysis may be a useful and efficient tool for taxonomical grouping and phylogenetic classification of different microsporidians in general., Wazid Hassan, B. Surendra Nath., and Obsahuje bibliografii
The aim of the present study was to estimate the genetic diversity of the cestode Echinococcus multilocularis Leuckart, 1863 in Poland based on sequence analysis of the mitochondrial genes of worms isolated from red foxes, Vulpes vulpes (Linnaeus). Overall, 83 adults of E. multilocularis from the same number of foxes in different parts of Poland were used for analysis. Sequences of the three mitochondrial genes, cytochrome b (cob), NADH dehydrogenase subunit 2 (nad2) and cytochrome c oxidase subunit 1 (cox1), were analysed. Seventy-four individual biological samples were successfully sequenced. Combined sequence analysis of these three genes exhibited fifteen Polish haplotypes (EmPL1-EmPL15). Most isolates (n = 29; 39%) were classified to the EmPL1 haplotype, which occurred mainly in the east, north and centre of Poland. Haplotype EmPL4 (n = 14; 19%) and other haplotypes appeared predominantly in the south and west area. Fourteen haplotypes were grouped in the European clade. One Polish haplotype (EmPL9) (n = 7, 10%) was assigned to the Asian clade with haplotypes from Japan and Kazakhstan. This haplotype was found only in northeast Poland and this is the westernmost report of haplotype of E. multilocularis belonging to the Asian clade in Europe. The investigation demonstrated that populations of E. multilocularis in Poland (and probably also in eastern Europe) included not only different European haplotypes but also those of the Asian origin., Jacek Karamon, Krzysztof Stojecki, Małgorzata Samorek-Pieróg, Ewa Bilska-Zajac, Mirosław Rózycki, Ewa Chmurzyńska, Jacek Sroka, Jolanta Zdybel, Tomasz Cencek., and Obsahuje bibliografii