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81.
82.
Using sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE), the different alleles encoded at the 6 glutenin loci and 3 ω-gliadin loci were identified from a set of 134 hexaploid and 128 tetraploid wheat accessions mainly grown in Portugal. In the hexaploid wheats (T. aestivum L.), a total of 56, 42 and 36 patterns were observed for high molecular weight-glutenin subunits (HMW-GS), low molecular weight-glutenin subunits (LMW-GS) and ω-gliadins respectively. For HMW-GS encoded at Glu-A1, Glu-B1 and Glu-D1 loci, 4, 10 and 6 alleles were observed, respectively. LMW-GS displayed similar polymorphism, as Glu-A3, Glu-B3 and Glu-D3 loci, which comprises 5, 9 and 3 alleles. Twenty-four alleles were observed for ω-gliadins found at Gli-A1, Gli-B1 and Gli-D1 loci with, 5, 16 and 3 alleles respectively. For tetraploid collection fifty different alleles were identified for the seven loci studied Glu-A1 (3), Glu-B1 (13), Glu-A3 (6), Glu-B3 (7), Glu-B2 (2), Gli-A1 (5) and Gli-B1 (14). The genetic distances within hexaploid and tetraploid wheats were presented using cluster representation. The mean value of genetic variation indices (H) for wheat storage protein loci was slightly lower in current commercially available varieties (0.592) and highest for old varieties (0.574).  相似文献   
83.
In this study, we used a pair of optical disdrometers, one under and one outside the maize canopy, to measure the drop-size and the velocity distribution of hydrometeors during 12 storms and identified four distinct regions by examining how the fraction of drops recorded on the throughfall changed with respect to the drop diameter. The first region, containing drops with diameters smaller than 0.5 mm, showed an elevated number on the throughfall. Their numbers were comparable to the numbers of drops that lacked enough energy to adhere to the leaf. The second region, featuring drops with diameters larger than 0.5 mm and smaller than 3 mm, had a number ratio very close to the canopy gap fraction, indicating that their most likely origin was direct throughfall. The third region entailed drops with diameters ranging from 3 mm to 5.5 mm that featured a high throughfall to rainfall count ratio, with one of the diameter classes having higher counts under the canopy than outside of it. Through simplified calculations, we showed that drop weights in this region should exceed surface tension forces and lead to their detachment. In the fourth and final region, the throughfall to rainfall ratio decreased converging to the canopy gap fraction. By comparing the number of drops on each of the 440 diameter/velocity classes under and outside of the canopy, we were able to identify preferential drop sizes on the throughfall, i.e. classes of drop diameters with higher drop-size distributions under the canopy. The drop classes presenting higher counts under the canopy had diameters ranging from 3.25 mm to 5.75 mm with velocities between 1.4 m s−1 and 5 m s−1. We were able to trace the origin of those drops to heights of between 0.10 m and 1.05 m within the canopy, confirming that these drops constitute the indirect throughfall. The capability to estimate the detachment height of drops allows us to reconstruct the drop-size distribution at different levels of the canopy and offers unique insight into the mechanics of interception, indirect throughfall formation and re-interception of raindrops by the maize canopy.  相似文献   
84.
BACKGROUND: Hematology tests are useful to evaluate physiologic disturbances in fish and can provide important information for the diagnosis and prognosis of disease. OBJECTIVES: The primary purpose of this study was to define reference intervals for thrombocytes and leukocytes in healthy channel catfish (Ictalurus punctatus). In addition, the morphologic, cytochemical, and ultrastructural features of blood cells were assessed. METHODS: Blood samples (0.5 mL) were collected into EDTA from 40 clinically healthy catfish on a commercial fish farm in Jaboticabal, Brazil. Thrombocyte, total WBC, and differential WBC counts were determined and reference intervals were calculated as the 25-95th percentiles of data. Thrombocyte and leukocyte morphology was assessed in blood smears stained with May Grünwald-Giemsa-Wright and ultrastructurally by transmission electron microscopy. Cytochemical staining patterns were described using periodic acid-Schiff (PAS), peroxidase, nonspecific esterase, alkaline phosphatase, and toluidine blue. RESULTS: Reference intervals were as follows: thrombocytes 58,802-99,569/microL; total WBCs 27,460-41,523/microL; lymphocytes 5380-11,581/microL; monocytes 2949-7459/microL; neutrophils 12,529-22,748/microL, and basophils 736-2003/microL. Neutrophils were positive for peroxidase and PAS; monocytes were positive for nonspecific esterase; and basophils were positive with toluidine blue. CONCLUSION: The morphologic and staining features of neutrophils and monocytes of channel catfish are similar to those of mammals, and the presence of basophils in this species was verified. These reference intervals and morphologic findings provide a foundation for future investigations on the functions and alterations of blood cells in channel catfish.  相似文献   
85.
The objective of the present work was to evaluate the teratogenic effects of the interaction between acetylsalicylic acid (ASA) and ethanol on the epithelium of the lingual mucosa in rat fetuses. On the 10th pregnancy day, a single intraperitoneal ethanol dose (2.96 g/kg body weight) (Group I), ASA (200 mg/kg body weight) (Group II) and ASA plus ethanol, in the same doses (Group III), or saline (Group IV - control), were administrated. The epithelial alterations were assessed by means of histological and morphometric methods, on posterior dorsal, anterior dorsal and ventral regions of the tongue. ASA reduced, in rat fetuses, the ethanol deleterious effects on nuclear size in the epithelial prickle cell of the lingual mucosa. On the other hand, ASA did not influence the effects of ethanol in both epithelial layers of the lingual mucosa, when the nuclear shape, cell volume or epithelial layers thickness were evaluated.  相似文献   
86.
This experimental controlled study was performed to evaluate the composition of autologous processed plasma (APP), and the effects of APP intra-articular injection into healthy equine metacarpophalangeal joints. The effects on joints were analysed with a short-phase protocol and a prolonged-phase protocol using saline-injected joints as controls. For the short protocol, horses received one intra-articular APP injection. Synovial fluid samples were collected prior to the injection and 3, 6, 24, 48, and 16 h after treatment. For the prolonged protocol, the joints received three weekly injections of APP, and samples were collected at 0, 7, 14, 21, and 28 days before APP administration. IL1-ra level was found to be increased in APP compared to plasma. Upon intra-articular administration of APP, transient (up to 24 h) increases in white blood cell (WBC) counts along with elevated protein and prostaglandin E2 (PGE2) concentrations were observed in the treated joints. Over the 28-day observation period, APP did not elicit changes relative to baseline levels, but WBC counts, PGE2 and chondroitin sulphate concentrations were lower than those found in the control. In conclusion, APP intra-articular injection induced a mild and transitory inflammatory response but no inflammation reaction was observed over a longer period of treatment and observation.  相似文献   
87.
Combining deep tillage (DT) with lime application at greater depths may improve sugarcane yield. The objective of this study was to evaluate the impact of conventional tillage (CT) and DT systems and liming on sugarcane productivity and soil physical attributes. The experiment was conducted in a clayey-textured Rhodic Hapludox soil cultivated with sugarcane for two growing seasons (first and third ratoons) using a randomized block design with four treatments and four repetitions. The treatments consisted of DT without liming (DT0), DT with liming (DT2), CT without liming (CT0) and CT with liming (CT2). In addition to sugarcane stalk and sugar yields, macroporosity (MA), microporosity (MI), total soil porosity (TP), weighted average diameter (WAD), aggregate stability index (ASI), soil penetration resistance (SPR), pH, potential acidity (H + Al), total soil organic carbon (SOC), particulate organic carbon (POC), mineral-associated organic carbon (MOC), calcium (Ca) and magnesium (Mg) were analysed. DT2 promoted the best soil conservation effect on sugarcane. In general, DT, regardless of lime application, reduced SOC and POC in soil surface layer. Nevertheless, in the long term, localized lime addition resulted in significant reductions in compaction, reaching values below 2 MPa. The soil fertility improvement provided by DT2 promoted increased sucrose concentrations and stalks yield. Considering that there was an improvement in the physical quality and fertility of soil for better plant development, the deep tillage with localized lime addition can be considered an effective alternative for sugarcane cultivation.  相似文献   
88.
89.
The cultivation of rubber trees in the humid tropical Amazon region is only possible with the use of crown grafts with species of Hevea sp. that are resistant to South American leaf blight – (SALB) [Microcyclus ulei (P. Henn.) v. Arx.]. However, it has been observed that plants with grafted crowns are not efficient in remobilizing magnesium from the crown to the latex. The experimental design was a randomized block, with three replicates. Five crown clones were studied (CPAA C 01, CPAA C 06, CPAA C 18, CPAA C 45, and CBA 2) with two magnesium (Mg) levels [source: magnesium sulfate(MgSO4): low-Mg (150 g plant?1 of MgSO4 × 7H2O] and high-Mg (450 g plant?1 of MgSO4 × 7H2O). The panel clone used for tapping was CNS AM 7905 (Hevea brasiliensis). The results showed that the Mg levels influenced the crown clones differently in relation to yield, efficiency index and leaf and soil Mg concentration. Clone CPAA C 01 with a high-Mg produced over 2.0 t ha?1 of dry rubber. Clones CPAA C 01 and CPAA C 45 were the most efficient, while clone CPAA C 06 showed moderate efficiency and clones CPAA C 18 and CBA 2 were inefficient in using Mg. The Mg concentration in the latex was not influenced by the two Mg levels, with the only differences being between the crown clones.  相似文献   
90.
European Journal of Plant Pathology - Multisite fungicides are an anti-resistance strategy to control Phakopsora pachyrhizi. Among the protective fungicides, mancozeb is a fungicide that has been...  相似文献   
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