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101.
ISSR molecular marker was used to investigate genetic diversity of ‘Dare Gazi’ genotypes of Mashhad Esteghlal orchard and its relationship with other commercial and native cultivars of pear. Among ‘Dare Gazi’ genotypes of Mashhad Esteghlal orchard 23 genotypes were selected base on difference in tree vigor, leaf color, shape and color of fruit and also 33 other commercial and native pear cultivars from Esteghlal orchard and other Mashhad commercial orchards were studied. A total number of 230 DNA fragments were obtained using 11 primers of which 225 were polymorphic. On average, each primer produced 20.9 bands. Dice similarity coefficient ranged from 0.27 (between ‘Dom Kaj’ and Asian pear) to 1 (between ‘Dare Gazi’ 1 and 2 genotypes). Sample cluster dendrogram indicated that 56 genotypes were divided into 12 distinct clusters. The dendogram generated on the principle of Unweight Pair Wise Method using Arithmetic Average (UPGMA) was constructed by Dice coefficient and the genotypes were grouped into 12 clusters. ‘Dare Gazi’ genotypes did not show 100% similarity due to seed propagation or mutation, as ‘Dare Gazi’ 3 and 18 genotypes had the lowest similarity coefficient (0.64). Asian pears were placed in a separate group from European pears. And ‘Dare Gazi’ genotypes from different orchards were grouped separately, but all of them are called as ‘Dare Gazi’ pear for convenience. ISSR molecular marker can well identify the genetic variability among genotypes and cultivars and found suitable for grouping them.  相似文献   
102.
Journal of Plant Diseases and Protection - Orobanche cumana Wallr. is an important new problem for sunflower crop in Tunisia. Little information is available on the behavior of sunflower to O....  相似文献   
103.
Lentil (Lens culinaris Medik.) is an important grain legume crop, mostly grown in semi-arid environments and often faces intermittent drought spells during different growth stages, which severely hamper its yield. This study, comprising of three separate experiments, was conducted to evaluate the potential of seed priming with CaCl2 in improving drought tolerance in lentil. In the first experiment, lentil seeds were hydroprimed (water) or osmoprimed with 0.5 and 1% CaCl2; while non-primed seeds were taken as control. In the second and third experiments, lentil seeds were subjected to pre-optimized osmopriming (1% CaCl2) and hydropriming followed by surface drying or re-drying of primed seeds to original weight. The first two experiments were conducted in petri plates, while, in experiment 3, seeds were planted in plastic pots containing peat moss, maintained at 75% water holding capacity (WHC; well-watered) or 50% WHC (water deficit). Hydropriming and osmopriming improved seed germination, seedling growth, biomass production, chlorophyll intensity, sugar accumulation and reduced the oxidative stress in lentil under water deficit. However, osmopriming (1% CaCl2) was more effective than the hydropriming in improving the lentil growth, biomass production, Ca accumulation and sugar metabolism under both well-watered and water deficit conditions. Seed surface drying, after priming, was more beneficial in improving the lentil performance, under both well-watered and water deficit conditions, than re-drying to original weight. Osmopriming (1% CaCl2) increased the seeding dry weight (67%), SPAD value (140%), leaf Ca concentration (56%), α-amylase activity (55%), total soluble sugars (48%) and reduced malanodialdehyde content (35.9%) and total antioxidant activity (29.2%) than un-primed seeds under water deficit. In conclusion, osmopriming improved the lentil performance under optimal and water deficit conditions through early and synchronized emergence, better sugar and Ca accumulation which reduced the oxidative damage and resulted in better seedling growth and biomass production.  相似文献   
104.
OBJECTIVE: To determine the nutritional behaviour of Tehranian adolescents. SUBJECTS AND METHODS: This study was undertaken on 7669 adolescents (4070 boys and 3599 girls) of 22 junior high schools and high schools as a representative sample of Tehranian adolescents. A validated knowledge, attitudes and practices (KAP) questionnaire and a food-frequency questionnaire (FFQ) were used. Factor analysis was used to determine the key questions. RESULTS: The mean ( +/- standard deviation) age and body mass index of the adolescents was 14 +/- 1 years and 27.2 +/- 11 kg m- 2. Although 82% of girls and 75% of boys had good nutritional knowledge, only 25% of boys and 15% of girls had good nutritional practice. Eighty-five per cent of adolescents knew that drinking too many soft beverages resulted in overweight or obesity, but only 4.5% of them did not drink soft beverages. Although 89% of adolescents knew that crisps and corn balls are not healthy snacks, 45% of them used such snacks during their break time. Thirty-seven per cent of adolescents preferred whole-grain biscuits to creamy wafer ones but only 10% of adolescents used whole-grain biscuits as a snack. The most frequently consumed snacks among Tehranian adolescents were sausage sandwiches, cocoa cola, crisps and corn balls, creamy wafers, cakes, chocolate and toffee. CONCLUSION: A low percentage of Tehranian adolescents have good nutritional behaviour and in most of them their nutritional practice does not accord with their nutritional knowledge. These results indicate the necessity of nutritional intervention in Tehranian adolescents.  相似文献   
105.
AIM: To evaluate the relationship between dietary diversity score (DDS) and cardiovascular risk factors in Tehranian adults. METHODS: In this population-based cross-sectional study, a representative sample of 581 subjects (295 males and 286 females) aged over 18 years, residents of Tehran, participated. Hypercholesterolaemia, hypertriglyceridaemia and low high-density lipoprotein cholesterol were defined according to the Adult Treatment Panel III guidelines of the National Cholesterol Education Program. Diabetes was defined as fasting plasma glucose concentration > or = 126 mg dl(-1) or 2-h post challenge glucose concentration > or = 200 mg dl(-1). Hypertension was defined on the basis of the sixth report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure. Dietary diversity was defined according to the Diet Quality Index revised. RESULTS: Mean (+/- standard deviation) DDS was 6.15 +/- 1.02. The probability of having diabetes (odds ratio (OR) among quartiles: 1.45, 1.26, 1.11 and 1.00, respectively; P for trend = 0.04) and hypertriglyceridaemia (OR = 1.41, 1.23, 1.05 and 1.00, respectively; P for trend=0.04) decreased with increasing quartile of the diversity score for whole grains. The probability of having obesity (OR among quartiles: 1.39, 1.06, 1.03 and 1.00, respectively; P for trend = 0.03), hypercholesterolaemia (OR = 1.46, 1.28, 1.11 and 1.00, respectively; P for trend = 0.03), hypertension (OR = 1.32, 1.17, 1.13 and 1.00, respectively; P for trend = 0.03) and high low-density lipoprotein cholesterol (LDL-C) (OR = 1.25, 1.12, 1.07 and 1.00, respectively; P for trend = 0.04) decreased with increasing quartile of the diversity score for vegetables. The probability of having hypercholesterolaemia, high LDL-C, hypertension and diabetes decreased with quartile of the DDS. But the probability of being obese increased with quartile of the DDS (P for trend = 0.03). CONCLUSION: DDS was inversely associated with cardiovascular risk factors in this cross-sectional study. Increased diversity scores of diets, to increase the variety score for vegetables, may be emphasised in programmes attempting to bring about changes in lifestyle.  相似文献   
106.
Sex identification in Pistacia species during the long juvenile stage is an economically desirable objective. Due to the lack of morphological methods to identify sex at this stage, the application of molecular markers is expected to facilitate breeding programs. The aim of our study was to identify a marker closely linked to sex loci in Pistacia atlantica Desf subsp. mutica, P. khinjuk, and P. vera subsp. Sarakhs. Samples were collected from both male and female plants of each species, and their band patterns were analyzed according to the presence or absence of specific bands. Thirty random amplified polymorphic DNA (RAPD) primers and a pair of sequence characterized amplified region (SCAR) primers were tested as potential markers of sex in wild Pistacia species. Among the RAPD primers, only BC1200 was found to amplify a specific sex band present in female plants. Based on our analysis of all individual samples, a fragment of approximately 300 bp was amplified in female trees but absent in male ones. Although sex determination mechanisms in Pistacia are still unknown, they may be controlled by a single locus that acts as a trigger. The SCAR technique has proved to be a reliable technique in gender determination of pistachio genotypes at the seedling phenophase. This method could reduce both the time and costs associated with breeding programs.  相似文献   
107.
108.
Journal of Plant Diseases and Protection - The honey bee (Apis mellifera), as one of the most important pollinating insects, plays a critical role in biodiversity conservation and global food...  相似文献   
109.
The process of agricultural unification will dominate the German scene for the next few years. At this stage, however, analysis and forecasts are hampered by the considerable problem concerning the viability of East German agriculture in a market economy and by the absence of reliable data in the German Democratic Republic (GDR). This can only be understood in terms of the agricultural situation in the GDR before unification, which is discussed in the first section. The political and economic incentives for German unification are described in the next section of this paper, focusing especially on the integration of the GDR into CAP. The third section considers some critical structural, legal, social, and economic constraints in the process of integrating the two agricultural systems. Finally, the implications for German agriculture as well as the challenges for the CAP will be addressed. Data were collected from interviews with key agricultural policy makers, farm organizations, commodity groups, consumer groups, and agricultural experts, as well as interviewing East German farmers. Additional data were compiled from government statistics, EC publications, and press reports. The conclusions reached in this research show the urgent need for the German government to reconsider the objectives and rationale for structural policies in agriculture, and point out that the new Germany, itself full of paradoxes and uncertainty, stands at the center of European agricultural disorder.Leila Sfeir Lueschen is Assistant Professor of Agricultural Economics at the University of Kentucky. She has researched issues pertaining to the structure of agriculture, agricultural policies, and socio-economic change. Most recently, she has been studying problems associated with the transformation of East German agriculture and its integration into the European Community. Dr. Lueschen's work has been published in English, German, and French.  相似文献   
110.
Background: Data shows vanadium protects pancreatic beta cells (BC) from diabetic animals. Whether this effect is direct or through the relief of glucose toxicity is not clear. This study evaluated the potential effect of oral vanadyl sulfate (vanadium) on glycemic status and pancreatic BC of normal and diabetic rats. Methods: Rats were divided into five groups of normal and diabetic. Diabetes was induced with streptozocin (40 mg/kg, i.v.). Normal rats used water (CN) or vanadium (1 mg/ml VOSO4, VTN). Diabetic rats used water (CD), water plus daily neutral protamine Hagedorn insulin injection (80 U/kg, ITD) or vanadium (VTD). Blood samples were taken for blood glucose (BG, mg/dL) and insulin (ng/dL) measurements. After two months, the pancreata of sacrificed rats were prepared for islet staining. Results: Pre-treated normal BG was 88 ± 2, and diabetic BG was 395 ± 9. The final BG in CD, VTD, and ITD was 509 ± 22, 138 ± 14, and 141 ± 14, respectively. Insulin in VTN (0.75 ± 0.01) and VTD (0.78 ± 0.01) was similar, higher than CD (0.51 ± 0.07) but lower than CN (2.51 ± 0.02). VTN islets compared to CN had larger size and denser central core insulin immunoreactivity with plentiful BC. CD and ITD islets were atrophied and had scattered insulin immunoreactivity spots and low BC mass. VTD islets were almost similar to CN. Conclusion: Besides insulin-like activity, vanadium protected pancreatic islet BC, and the relief of glucose toxicity happening with vanadium had a little role in this action. Key Words: Vanadium, Rats, Diabetes, Protection, Beta cells  相似文献   
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