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692. Estimations of the critical temperatures for development of the pistachio psylla, Agonoscena pistaciae (Hemiptera: Psyllidae)
- Creator:
- Hassani, Mohammad Reza, Arbab, Abbas, Izadi, Hamzeh, and Nouri-Ganbalani, Gadir
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Psyllidae, Agonoscena pistaciae, critical temperature, developmental rate, 2, and 59
- Language:
- English
- Description:
- The pistachio psylla, Agonoscena pistaciae Burckhardt & Lauterer (Hemiptera: Psyllidae), is a major pest of pistachio trees throughout the pistachio producing regions in Iran. The effect of temperature on the developmental rates of eggs and nymphs of A. pistaciae was determined at different constant temperatures, i.e. 15, 20, 25, 30, 32.5 and 35 ± 0.5°C. The relationships between temperature and developmental rates were described by linear and the non-linear Lactin models. These models were evaluated based on R2, RSS, AIC and R2adj. The estimated value of the lower temperature threshold for egg, nymph and egg to adult development based on the linear model was 8.06, 10.38 and 9.97°C, respectively, and based on the Lactin model was 8, 11.55 and 11.2°C, respectively. Thermal constants estimated using the linear model, were 88.5, 243.90 and 333.33 DD, respectively, for egg, nymph and egg to adult development. These results indicate that the linear model gives a better description of the relationship between developmental rate and temperature for A. pistaciae than the non-linear model. These results could be incorporated into forecasting models used in the integrated pest management of this pest. and Mohammad Reza Hassani, Abbas Arbab, Hamzeh Izadi, Gadir Nouri-Ganbalani.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
693. Evaluating the link between photosynthetic capacity and leaf vascular organization with principal component analysis
- Creator:
- Polutchko, S. K., Stewart, J. J., Demmig-Adams, Barbara, and Adams, William W.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, growth temperature, high light, low light, phloem parenchyma cells, xylem, 2, and 581
- Language:
- Multiple languages
- Description:
- Significant linear relationships between photosynthetic capacity and principal components loaded by phloem cell numbers and tracheary elements per minor vein as well as the latter two normalized for vein density (proxy for apoplastic phloem loading capacity involving membrane transporters) were revealed for all apoplastic loaders (summer annuals and winter annual Arabidopsis thaliana). In addition, significant linear relationships between photosynthetic capacity and a principal component loaded by tracheary element cross-sectional areas and volumes per unit of leaf area (water flux capacity proxy) was present for symplastic and apoplastic loaders. Lastly, a significant linear relationship between photosynthetic capacity and a principal component loaded by phloem cell cross-sectional areas and volumes per unit of leaf area (proxy for symplastic loading capacity involving cytosolic enzymes for companion cells) was revealed for summer annual symplastic loaders as well as for A. thaliana (in the case of sieve elements, a proxy for sugar export capacity from the leaves)., S. K. Polutchko, J. J. Stewart, B. Demmig-Adams, W. W. Adams., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
694. Evaluating the role of intestinal parasites in the high rates of irritable bowel syndrome in South America: a pilot study
- Creator:
- Vasquez-Rios, George, Machicado, Jorge D, Gamero, Maria T, Pezua, Adriana, Betancourt, Angel B, Terashima, Angelica, and Marcos, Luis A
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitické organismy, tračník, parasitic organisms, colon, Jižní Amerika, South America, soil-transmitted helminths, Blastocystis sp., functional gastrointestinal diseases, 2, and 59
- Language:
- English
- Description:
- There is limited data on the role of intestinal parasites in irritable bowel syndrome (IBS) in South America. We evaluated the association between intestinal parasitism and IBS status in Peru. Intestinal parasites were detected in 43% of the IBS cases and in 51% of the controls (P = 0.4). After excluding those infected by any parasite, the IBS prevalence remained high (22%; P = 0.7). No statistically significant difference was noted between IBS cases and controls in terms of monoparasitism, biparasitism or multiparasitism. Furthermore, the protist Blastocystis sp. was inversely associated with IBS., George Vasquez-Rios, Jorge D. Machicado, Maria T. Gamero, Adriana Pezua, Angel B. Betancourt, Angelica Terashima, Luis A. Marcos., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
695. Evaluation of photosynthetic electron flow using simultaneous measurements of gas exchange and chlorophyll fluorescence under photorespiratory conditions
- Creator:
- Ye, Z. P., Yu, Q., and Kang, H. J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, light-response curve of photosynthesis, light-response curve of photosynthetic electron flow via PSII, photosynthesis, photosynthetic electron flow via PSII, 2, and 58
- Language:
- Multiple languages
- Description:
- Simultaneous measurements of leaf gas exchange and chlorophyll fluorescence for Koelreuteria paniculata Laxm. at 380 ± 5.6 and 600 ± 8.5 μmol mol-1 were conducted, and the photosynthetic electron flow via photosystem II (PSII) to photosynthesis, photorespiration, and other electron-consuming processes were calculated. The results showed that the photosynthetic electron flow associated with carboxylation (Jc), oxygenation (Jo), and other electron-consuming processes (Jr) were 72.7, 45.7, and 29.4 μmol(e-) m-2 s-1 at 380 μmol mol-1, respectively; and 86.1, 35.3, and 48.2 μmol(e-) m-2 s-1 at 600 μmol mol-1, respectively. Our results revealed that other aspects associated with electronconsuming processes, except for photosynthesis and respiration, were neither negligible nor constant under photorespiratory conditions. Using maximum net photosynthetic rate (Pmax), day respiration (R), photorespiration rate (Rl), and maximum electron flow via PSII (Jmax), the use efficiency of electrons via PSII at saturation irradiance to fix CO2 was calculated. The calculated results showed that the use efficiency of electrons via PSII to fix CO2 at 600 μmol mol-1 was almost as effective as that at 380 μmol mol-1, even though more electrons passed through PSII at 600 μmol mol-1 than at 380 μmol mol-1., Z. P. Ye, Q. Yu, H. J. Kang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
696. Evaluation of photosynthetic performance of wheat cultivars exposed to boron toxicity by the JIP fluorescence test
- Creator:
- Öz, M. T., Turan, Ö., Kayihan, C., Eyidoğan, F., Ekmekçi, Y., Yücel, M., and Öktem, H. A.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, pšenice, bor, photosynthesis, wheat, boron, chlorophyll fluorescence, fluorescence transient, performance index, Triticum aestivum L, 2, and 581
- Language:
- Multiple languages
- Description:
- The changes in growth and photosynthetic performance of two wheat (Triticum aestivum L.) cultivars (Bolal-2973 and Atay-85) differing in their sensitivity to boron (B) toxicity were investigated under toxic B conditions. Eight-day old seedlings were exposed to highly toxic B concentrations (5, 7.5, and 10 mM H3BO3) for 5 and 9 days. Fast chlorophyll a fluorescence kinetics was determined and analysed using JIP test. Growth parameters, tissue B contents, and membrane damage were measured at two stress durations. The photochemical performance of PSII was hindered more in the sensitive cultivar (Atay-85) than that of the tolerant one (Bolal-2973) under B toxicity. The increase in the B concentration and stress duration caused membrane leakage in both cultivars. However, higher membrane damage was observed in Atay-85 compared to Bolal-2973. Additionally, significant reduction of growth parameters was observed in both cultivars at toxic B concentrations. The accumulation of B was higher in shoots than in roots of both cultivars. Nevertheless, Atay-85 translocated more B from roots to leaves compared to Bolal-2973. The advantages of certain JIP test parameters were demonstrated for evaluation of PSII activity in plants exposed to B stress. Evaluation of photosynthetic performance by JIP test as well as assessment of growth and tissue B content might be used to determine the effects of B toxicity in wheat. The results indicated lesser sensitivity to B toxicity in Bolal-2973 compared to Atay-85., M. T. Öz, Ö. Turan, C. Kayihan, F. Eyidoğan, Y. Ekmekçi, M. Yücel, H. A. Öktem., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
697. Evaluation of photosynthetic potential of wheat genotypes under drought condition
- Creator:
- Sikder, S., Foulkes, J., West, H., De Silva, J., Gaju, O., Greenland, A., and Howell, P.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- pšenice, sucha, photosynthesis, wheat, Velká Británie, leaf gas-exchange measurements, leaf gas exchange, pot experiment, water regimes, drought, 2, and 581
- Language:
- Multiple languages
- Description:
- Water availability is one of the most important limiting factors in agriculture worldwide, particularly in arid and semiarid regions. Six spring wheat genotypes, i.e. three UK cultivars Cadenza, Paragon, and Xi-19 and three synthetic-derived lines L-22, L-24, and L-38, were grown in a phytotron under well-watered (until 40 days after sowing) and drought conditions. The aim of the study was to evaluate the traits related to photosynthetic capacity (net photosynthesis rate, stomatal conductance, internal CO2 concentration, transpiration rate, carboxylation capacity, instantaneous and intrinsic water-use efficiency) and plant biomass production in the cultivars and synthetic derivatives of wheat genotypes under well-watered and water-limited conditions. Genotypic variations in gas-exchange traits including net photosynthetic rate, carboxylation capacity, instantaneous water-use efficiency, and biomass yield were found amongst genotypes. Drought significantly reduced the total dry matter per plant. The synthetic derivatives L-22 and L-24 showed higher performance of stomata for most of the stomatal aperture characteristics. Total dry matter was positively related to net photosynthetic rate and to instantaneous and intrinsic water-use efficiencies. Finally, net photosynthetic rate was also positively related to stomatal conductance and transpiration rate under both the well-watered and water-limited drought conditions., S. Sikder, J. Foulkes, H. West, J. De Silva, O. Gaju, A. Greenland, P. Howell., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
698. Evaluation of reflectance spectroscopy indices for estimation of chlorophyll content in leaves of a tropical tree species
- Creator:
- Mielke, M. S., Schaffer, B., and Schilling, A. C.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, anthocyanins, ecosystem restoration, Eugenia uniflora, leaf mass per area, SPAD-502, 2, and 58
- Language:
- Multiple languages
- Description:
- The effectiveness of eight spectral reflectance indices for estimating chlorophyll (Chl) content in leaves of Eugenia uniflora L., a tropical tree species widely distributed throughout the world and a key species for ecosystem restoration projects, was evaluated. Spectral reflectance indices were tested using sun and shade leaves with a broad variation in leaf mass per area (LMA). Shortly after plants were exposed to chilling temperatures, there was a dramatic visible change in some sun leaves from green to red. Prior to testing Chl-related reflectance indices, the green and red leaves were separated according to the anthocyanin reflectance index (ARI). Slightly green to dark green leaves corresponded to an ARI value less than 0.11 (n = 107), whereas slightly red to red leaves corresponded to an ARI value greater than 0.11 (n = 35). To estimate leaf Chl, two simple reflectance indices (SR680 and SR705), two normalized difference indices (ND680 and ND705), two modified reflectance indices (mSR705 and mND705), a modified Chl absorption ratio index (mCARI705) and an index insensitive to the presence of anthocyanins (CIre) were evaluated. Good estimates of leaf Chl content were obtained using the reflectance indices tested regardless of the presence of anthocyanins and changes in LMA. Based on the coefficients of determination (r2) and the root mean square errors (RMSɛc) the best results were obtained with reflectance indices measured at wavelengths of 750 and 705 nm. Considering the performance of the models the best reflectance indices to estimate Chl contents in E. uniflora leaves with a broad variation in LMA and anthocyanin contents was SR705 and mCARI705., M. S. Mielke, B. Schaffer, A. C. Schilling., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
699. Evaluation of responses of different ant species (Formicidae) to the scavenger deterrent factor associated with the entomopathogenic nematode-bacterium complex
- Creator:
- Gulcu, Baris, Hazir, Selcuk, Lewis, Edwin E, and Harry K Kaya
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- mravencovití, ants, Formicidae, scavenger deterrent factor, pathogens, Heterorhabditis, Photorhabdus, 2, and 59
- Language:
- English
- Description:
- According to previous observations, it was hypothesized that the feeding behavior of some ant species would be deterred by a scavenger deterrent factor (SDF), whereas for other species it would not. The effects of the SDF were studied on 11 ant species in three different subfamilies: Dolichoderinae Forel, 1878, Formicinae Latreille, 1809, and Myrmicinae Lepeletier de Saint-Fargeau, 1835. The experiments were conducted from 2014-2015 in Davis, California, United States, Aydin, Turkey, and Duzce, Turkey. Five-day-old Heterorhabditis bacteriophora (Poinar, 1976), (Hb)-killed and freeze-killed Galleria mellonella (Linnaeus, 1758) were exposed to ant colonies in the field for 3 to 4 h. Seven ant species fed significantly less on Hb-killed insects than freeze-killed insect. On the other hand, there was no significant difference in cadaver consumption with five species, but Liometopum occidentale Emery, 1895 did consume a higher rate of Hb-killed insects than freeze-killed insects and was not deterred by SDF. It was also observed that four ant species took Hb-killed insects into the nests, but two Myrmicinae species, Pogonomyrmex subdentatus Mayr, 1870 and Messor meridionalis (André, 1883) removed the cadavers after 30 min, whereas two Formicinae species, Cataglyphis nodus (Brullé, 1833) and Formica fusca Linnaeus, 1758, retained the cadavers in the nest. It was assumed that the latter two species consumed both Hb-killed and freeze-killed insects. Further studies are needed to explain why L. occidentale C. nodus and F. fusca are not deterred by SDF., Baris Gulcu, Selcuk Hazir, Edwin E. Lewis, Harry K. Kaya., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
700. Evaluation of wild Arachis species for cultivation under semiarid tropics as a fodder crop
- Creator:
- Nautiyal, P. C., Rathnakumar, A. L., Kulkarni, G., and Sheshshayee, M. S.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- efektivnost fotosystému II, zelená biomasa, nedostatek vody, efektivita využívání vody, krmné plodiny, semiaridní tropy, podzemnice, efficiency of photosystem II, green biomass, leaf water relation traits, semiarid tropics, Arachis, water scarcity, water-use efficiency, fodder crop, 2, and 581
- Language:
- Multiple languages
- Description:
- Wild Arachis genotypes were analysed for chlorophyll a fluorescence, carbon isotope discrimination (ΔC), specific leaf area (SLA), and SPAD readings. Associations between different traits, i.e., SLA and SPAD readings (r =-0.76), SLA and ΔC (r = 0.42), and ΔC and SPAD readings (r = 0.30) were established. The ratio of maximal quantum yield of PSII photochemistry (Fv/Fm) showed a wider variability under water deficit (WD) than that after irrigation (IR). Genotypes were grouped according to the Fv/Fm ratio as: efficient, values between 0.80 and 0.85; moderately efficient, the values from 0.79 to 0.75; inefficient, the values < 0.74. Selected Selected genotypes were evaluated also for their green fodder yield: the efficient genotypes ranged between 3.0 and 3.8, the moderately efficient were 2.6 and 2.7, the inefficient genotypes were of 2.3 and 2.5 t ha-1 per year in 2008 and 2009, respectively. Leaf water-relation traits studied in WD and IR showed that the efficient genotypes were superior in maintenance of leaf water-relation traits, especially, under WD. Potential genotypes identified in this study may enhance biomass productivity in the semiarid tropic regions., P. C. Nautiyal, A. L. Rathnakumar, G. Kulkarni, M. S. Sheshshayee., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public