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131.
132.
Allium tuncelianum (Kollman) Özhatay, Matthew & ?iraneci is a native species to the Eastern Anatolia. Its plant architecture resembles garlic (Allium sativum L.) and it has mild garlic odor and flavor. Because of these similarities between two species, A. tuncelianum has been locally called “garlic”. In addition, both A. tuncelianum and garlic has 16 chromosomes in their diploid genomes. Recently, A. tuncelianum has been suggested as the wild progenitor species of garlic. In this study, amplified fragment length polymorphisms (AFLP) markers and nucleotide sequence analysis of the internal transcribed spacer region (ITS) were used to assess genetic and phylogenetic relationships among A. tuncelianum, garlic and some other Allium species. AFLP analysis demonstrated that A. tuncelianum and garlic are genetically distinct and they are likely different species. Phylogenetic analyses based on the nucleotide sequence of ITS suggested that A. tuncelianum and garlic are distinct species and placed A. tuncelianum, garlic, Allium ampeloprasum and Allium scorodoprasum into the same clade in the neighbor joining dendrogram and in the consensus tree of parsimony analysis. However, A. tuncelianum was phylogenetically less related to garlic than either A. ampeloprasum or A. scorodoprasum, suggesting that A. tuncelianum may not be the immediate wild ancestor species of garlic. Further studies to generate hybrid progeny between A. tuncelianum and garlic (if possible) could provide more information on the homology between the chromosomes of A. tuncelianum and garlic and genetic relationships between these two species.  相似文献   
133.
The objective was to compare pregnancy per artificial insemination (P/AI) with conventional (CS) or sex‐sorted semen (SS) in dairy cows subjected to one of the three timed AI protocols. Cows (n = 356) were randomly assigned to synchronization with Ovsynch (OVS), Presynch–Ovsynch (PO) or Double‐Ovsynch (DO) and inseminated on Day 77 ± 3 postpartum with either frozen‐thawed SS (n = 182) or CS (n = 184) of the same bull. More cows were cyclic at the beginning of breeding Ovsynch increased (p < 0.01) with presynchronization and it was greater for DO than PO (OVS = 78.5%, PO = 85.1%, DO = 95.6%). Overall, P/AI for SS and CS increased with presynchronization (p < 0.05) on Days 31 (OVS = 35.5%, PO = 47.1%, DO = 48.3%) and 62 (OVS = 30.1%, PO = 43.8%, DO = 43.9%). Regardless of synchronization treatments, insemination with SS reduced P/AI (p < 0.02) on Days 31 (38.1% vs. 50.6%) and 62 (34.5% vs. 45.6%) compared with CS. No interaction was observed between synchronization treatment and type of semen for P/AI, although in cows receiving CS, P/AI was numerically greatest for PO (OVS = 42.0%, PO = 59.3%, DO = 49.0%), and in cows receiving SS, it was numerically greatest for those inseminated following DO (OVS = 27.9%, PO = 35.5%, DO = 47.6%). Thus, presynchronization improved P/AI in cows inseminated with sex‐sorted or conventional semen.  相似文献   
134.
Myosin V is a dimeric molecular motor that moves processively on actin, with the center of mass moving approximately 37 nanometers for each adenosine triphosphate hydrolyzed. We have labeled myosin V with a single fluorophore at different positions in the light-chain domain and measured the step size with a standard deviation of <1.5 nanometers, with 0.5-second temporal resolution, and observation times of minutes. The step size alternates between 37 + 2x nm and 37 - 2x, where x is the distance along the direction of motion between the dye and the midpoint between the two heads. These results strongly support a hand-over-hand model of motility, not an inchworm model.  相似文献   
135.
Salinity has deleterious effects on plant growth and development through membrane stability, photosynthetic activity, protein content, and ionic composition; however, salicylic acid (SA) could restore these properties in plants. The objective of this study was to determine the ameliorative effects of SA as foliar pre-treatments on membrane permeability, proline and protein contents, chlorophyll a, b and total chlorophyll and ionic composition of strawberry cv. ‘Camarosa’ under saline conditions. Membrane permeability and proline content significantly increased and protein and chlorophyll contents significantly decreased by 6 mS cm?1 application without SA treatment compared with the control (2 mS cm?1) treatment. Membrane permeability decreased from 6.9 in 0 mM SA treatment to 5.2 by application of 1.0 mM SA under saline conditions and same to the control (5.2). Compared with 0 mM SA treatment, the average increases of proline and protein contents were 66.7% in 0.25 mM SA treatment and 62.2% in 0.1 mM SA treatment in 6 mS cm?1 level, respectively. Chlorophyll b and total chlorophyll significantly increased by 0.25 mM SA treatments under saline conditions. The lowest and the highest chlorophyll b and total chlorophyll were obtained from 0 mM SA treatment (19.6 and 44.5 mg L?1) and 0.25 mM SA treatment (28.6 and 52.9 mg L?1) in 6 mS cm?1 salinity level. Ionic compositions of leaves were significantly affected by salinity and SA treatments. Nitrogen in 1.0 mM SA treatment and P contents of leaves in 0.1 mM SA treatment significantly increased but Na and Cl contents of leaves significantly decreased by SA treatments in 6 mS cm?1 salinity level. The results of this study were clearly indicated that the SA application on strawberry plants could ameliorate the deleterious effect of salt stress on membrane permeability, proline, protein, and chlorophyll contents. Therefore, SA treatment could offer an economic and simple application to salinity stress.  相似文献   
136.
ABSTRACT

Three vegetative rootstocks of plum (Prunus domestica), Marianna GF 8-1 (Prunus cerasifera × munsoniana), Myrobolan B (P. Cerasifera) and Pixy (P. Insititia) were grown in pots containing sand and irrigated with complete nutrient solution to investigate the effect of calcium sulfate supplied to the nutrient solution on plants grown under salt stress. Treatments were (1) control (C): nutrient solution alone; (2) S (salinity stress): 40 mM NaCl; (3) S+Ca1: 40 mM NaCl +2.5 mM calcium (Ca) and (4) S+Ca2: 40 mM NaCl + 5 mM Ca. Calcium was supplied as CaSO4. The plants grown under 40 mol L?1 NaCl produced less dry matter and had lower chlorophyll content than those without NaCl. Supplementary CaSO4 at both 2.5 and 5 mM concentrations ameliorated the negative effects of salinity on plant dry matter and chlorophyll content. Salt treatment impaired membrane permeability by increasing electrolyte leakage. The addition of calcium sulfate partially maintained membrane permeability. Sodium (Na) concentration in plant tissues increased in both leaves and roots of plants under the high NaCl treatment. Pixy had much lower Na. The CaSO4 treatments lowered significantly the concentrations of Na in both leaves and roots. Pixy was more tolerant to salinity than the other two rootstocks. The accumulation of Na in leaves and roots indicates a possible mechanism whereby Pixy copes with salinity in the rooting medium, and/or may indicate the existence of an inhibition mechanism of Na transport to leaves. Concentrations of Ca and K were lower in the plants grown at high NaCl than in those under the control treatment, and these two element concentrations were increased by calcium sulfate treatments in both leaves and roots, but remained lower than control values in most cases.  相似文献   
137.
This study has been carried out in the Western Mediterranean Region of Turkey on seven different Honamli goat flocks. The aim of this study was to determine the growth characters, survival rate (till weaning, 105th day), some reproductive characteristics and marketable milk yield. The data were collected from 516 does and 210 kids (125 buckling and 85 doelings). The results indicate that the numbers of multiple birth and litter size were 32.8 % and 1.35 respectively. Survival rates of kids at the 30th, 90th, and 105th days were 98.5, 97.2, and 97.2?%, respectively. The average birth weight for the buckling and doelings was 4.1 and 3.7?kg, respectively. The average weaning weights for buckling and doelings were 26.9 and 23.4?kg, respectively. The effects of dams?? age, on sex and birth type on the growth of Honamli kids were statistically significant (p?<?0.05, p?<?0.01, and p?<?0.001). While the diameters of erythrocytes of Honamli goats are smaller, the density of hemoglobin in the erythrocytes is more than Asian, Indian, and American caprine breeds. The average lactation length and marketable milk yield was assessed to be at 210.3?days and was 89?L, respectively. The growth characteristics of Honamli kids at weaning age were assessed to be higher than most of the other goat breeds in Turkey. The results further indicated that there is a significant variation in the production traits among the different Honamli goat flocks. Production traits of Honamli goats at different breeding conditions should further be investigated to come to a definite conclusion.  相似文献   
138.
A feeding trial was conducted to investigate the effects of the replacement of dietary fish meal and fish oil with oilseed meals (soybean or canola) and canola oil on growth, nutrient utilization, body composition, diet digestibility and hematological parameters of rainbow trout Oncorhynchus mykiss. Seven diets were used; the control diet (designated FM) contained fish meal and fish oil as the main protein and lipid sources. For the experimental diets, 40% of fish meal protein was substituted with soybean meal, canola meal or a soybean/canola meal mixture, and these diets (designated SM, CM and SCM, respectively) contained fish oil as the lipid source. Three additional diets (SM?+?CO, CM?+?CO and SCM?+?CO) were formulated with the same vegetable protein meals but with fish oil replaced by canola oil. Fish were fed twice daily to apparent satiation for 11?weeks. The growth of fish fed the CM?+?CO diet was significantly lower than that of fish fed the FM, SCM, SM?+?CO and SCM?+?CO diets. The feed conversion ratio (FCR) was significantly better in fish fed the FM and SCM?+?CO diets than in fish fed the CM and CM?+?CO diets. Furthermore, feed intake was significantly lower for fish fed the CM?+?CO diet than in fish fed the SCM diet, and lipid digestibility of the CM?+?CO diet was significantly lower than that of all other diets. No significant differences of body composition were observed. Circulating leukocyte levels, leukocyte ratios and serum lysozyme activity remained unaffected by dietary treatment. However, it was observed that fish fed the CM?+?CO diet displayed hematocrit levels significantly lower (P?<?0.05) than that of fish fed the other diets. The results indicate that when diets contain either fish oil or canola oil, canola meal and soybean meal can be incorporated into rainbow trout feeds at a combined 32% inclusion level (replacing 40% of fish meal protein) without inducing significant negative effects on growth, nutrient utilization or health.  相似文献   
139.
Genetic transformation is a useful technique to complement conventional breeding in crop improvement. Although carrot has been a model organism for in vitro embryogenesis study, genetic transformation of carrot is still lengthy and labor intensive. An efficient transformation and detection system is desirable. Direct infection of Agrobacterium to carrot calli has provided an easy way for carrot genetic transformation. To improve the efficiency of antibiotic selection in this method, we report the combined use of an improved green-fluorescent protein, referred to as smGFP, to establish a versatile selection method for carrot callus transformation system. By combining antibiotic selection with the bright fluorescence observed in the callus tissue, we were able to easily identify stable transformants in early stage of the transformation process. In addition to the GFP expression of the callus cells, the transgenic nature of callus cells was confirmed with Southern and Western analysis. We found we can link the simplicity of carrot-callus-cell transformation, early detection of stable transformants with antibiotic selection, visualization of GFP fluorescence, and molecular analysis (Southern and Western) of callus tissue (non-photosynthetic tissue) to provide a more efficient way in identifying stable transformants at early stage of carrot transformation.  相似文献   
140.
Genetic transformation is a useful technique to complement conventional breeding in crop improvement. Although carrot has been a model organism for in vitro embryogenesis study, genetic transformation of carrot is still lengthy and labor intensive. An efficient transformation and detection system is desirable. Direct infection of Agrobacterium to carrot calli has provided an easy way for carrot genetic transformation. To improve the efficiency of antibiotic selection in this method, we report the combined use of an improved green-fluorescent protein, referred to as smGFP, to establish a versatile selection method for carrot callus transformation system. By combining antibiotic selection with the bright fluorescence observed in the callus tissue, we were able to easily identify stable transformants in early stage of the transformation process. In addition to the GFP expression of the callus cells, the transgenic nature of callus cells was confirmed with Southern and Western analysis. We found we can link the simplicity of carrot-callus-cell transformation, early detection of stable transformants with antibiotic selection, visualization of GFP fluorescence, and molecular analysis (Southern and Western) of callus tissue (non-photosynthetic tissue) to provide a more efficient way in identifying stable transformants at early stage of carrot transformation.  相似文献   
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