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61.
菜豆荚斑驳病毒的RT-PCR检测   总被引:1,自引:1,他引:1  
魏梅生  相宁  张春泉 《大豆科学》2005,24(4):317-319
菜豆荚斑驳病毒是对大豆经济具有重要影响的病毒.根据已报道的菜豆荚斑驳病毒外壳蛋白基因序列,设计出一对特异性引物,采用RT-PCR法,可有效地扩增出BPMV不同亚组的4个分离物,得到650 bp大小的PCR产物.这种方法能成功地检测出大豆病叶中的BPMV,结果和酶联检测是一致的,而对大豆种皮中BPMV的检测效果不佳,建议采用酶联的方法进行检测.  相似文献   
62.
In many areas of North Africa, barley is often the only possible rainfed crop. In these regions water deficit is the primary constraint affecting crop production. Twenty barley landraces collected from different localities in south Morocco and four modern varieties were characterized in two field experiments, one under well-irrigated and one under limited-irrigated conditions. Nine agro-morphological characters were evaluated: Plant height, tiller number per plant, number of grains per spike, number of spikes per plant, spike weight, spike length, plant weight (PW), number of internodes of rachis (NIR), and length of the last internode of rachis. The correlation coefficients among characters were nearly the same in the well- and limited-irrigated experiment. Under limited-irrigated conditions, plant growth was significantly decreased as measured by all characters except NIR, which was unaffected. The percentage of reduction, ranging from 80.08% to 5.82%, was recorded on PW and NIR, respectively. The injury index ranging from 4.02 to 0.06 was recorded on PW and NIR, respectively. Using discriminant analysis the genotypes were arranged in three, clearly separated groups that varied in their tolerance to drought stress.  相似文献   
63.
ABSTRACT

Sulfur (S) availability is a characteristic of conservation tillage. We studied the effects of S on sunflower yield and fatty acid profile under conventional and conservation tillage in silty clay soil of D.I. Khan, Pakistan. Conventional tillage consisted of disk plowing followed by tiller and rotavator, while conservation tillage comprises tiller and disc harrowing. Treatments comprise six sulfur levels (S1 = 0, S2 = 20 kg S ha?1 at sowing, S3 = 10 kg S ha?1 at sowing +10 kg S ha?1 25 days after sowing (DAS), S4 = 40 kg S ha?1 at sowing, S5 = 20 kg S ha?1 at sowing + 20 kg S ha?1 25 DAS, and S6 = 20 kg S ha?1 at sowing + 10 kg S ha?1 25 DAS + 10 kg S ha?1 50 DAS) replicated thrice. After 2 years of experimentation, soil samples were collected (from 0 to 0.30 m depth) for organic matter (OM), total soil N (TSN), and available sulfur analysis. Conservation tillage significantly increased OM, TSN, and S contents in 0–0.30 m soil compared to conventional tillage. Likewise, sunflower plants showed higher achene yield, better fatty acid profile, and net economic returns in conservation tillage than in conventional tillage. Application of 20 kg S ha?1 at sowing and 10 kg S ha?1 at each 25 and 50 DAS recorded significantly higher achene yield, higher oil, and linoleic acid contents; however, oleic and oleic/linoleic ratio did not increase with higher S rates. Conservation tillage was effective in increasing OM, TSN, and available S besides increasing yield and economics in silty clay soil.  相似文献   
64.
This study was undertaken to evaluate the effect of body condition score (BCS) on testicle and epididymis biometrics, semen characteristics and testosterone level in Egyptian Jack. This study was conducted on 50 mature Jacks divided according to their body condition score into four groups: Poor (G1), moderate (G2), good (G3) and fat (G4). The complete testis was collected immediately after execution in the Giza Zoo abattoir; then, the epididymis was carefully dissected at the testicular junction. Biometrical measures including length, weight and volume were determined for the right and left testis and epididymis. Also, epididymal sperm was collected from all examined animas and evaluated for sperm concentration, progressive motility, viability and sperm abnormalities. Serum samples were collected for determination of total testosterone level. Results showed that the body condition score of the examined animal affects their biometrical measure of testicles and epididymis. There is a significant decrease (p < .05) in biometrical measures for the testicles and epididymis, sperm concentration, motility, viability and testosterone level in poor BCS animals (G1). The highest values were recorded in Good BCS (G3) Jacks. Conclusion: Jacks with good BCS (G3) should be selected for breeding activity in donkey.  相似文献   
65.
This work was designed to evaluate the ovarian follicular development, oocytes morphology, methods of oocytes reterival, and the effect of different in vitro maturation (IVM) media on cumulus cell expansion and nuclear maturation of Jennies oocytes. Experiment 1, the number of small (<6 mm), medium (6 to 9 mm) and large size (>10 mm) ovarian follicles was recorded. Cumulus-oocyte-complexes (COCs) were reterived and classified into 4 Grades based on their cumulus-cells investment and the homogenous of the ooplasm. In Experiment 2, COCs were recovered by using 18-G, 20-G needle or slicing and scraping of ovarian follicles to determine the number and morphology of the recovered COCs. In Experiment 3, Grade A and B COCs were IVM in DMEM-HG, DMEM-LG, DMEM-F12, TCM199, TCM199-F12 or CR1aa media supplemented with 10 % FCS?+?10 μg FSH/mL?+?10 IU hCG/mL?+?50 μg/mL gentamicin. Maturation was performed for 36 h at 38.5 °C under 5 % CO2 in humidified air. After IVM, cumulus cell expansion and oocytes nuclear canfiguration were determined. An average of 6.40?±?0.26 follicles was recorded per Jenny ovary, representing 3.37?±?0.46, 1.89?±?0.14 and 1.14?±?0.16, for the small, medium and large size follicles, respectively. Oocyte recovery was higher (P?P?P?P?P?P?P?P?Conclusion: Slicing and scraping or aspiration of follicles using 18-G needle increased the number and percentage of Grade A Jennies oocytes. TCM199-F12, CR1aa and TCM199 medi are more suitable for IVM of Jenny oocytes by promoting cumulus cells expansion and nuclear maturation to M II stage.  相似文献   
66.
Nitrogen and sulfur play an important role in maize production. The aim of this study was to evaluate the effect of nitrogen (N) and sulfur (S) levels applied in various ratios on maize hybrid Babar yield at Peshawar in 2011 and 2013. Four N levels (120, 160, 200 and 240 kg N ha?1) and four S levels (20, 25, 30 and 35 kg S ha?1) were applied in three splits: a, at sowing; b, V8 stage; c, VT stage in ratios of 10:50:40, 20:50:30 and 30:50:20. Grains ear?1, thousand grain weight, grain yield ha?1 and soil pH were significantly affected by years (Y), N, S and their ratios, while no effect of N, S and their ratios was noted on ears plant?1. Maximum grains ear?1 (390), thousand grain weight (230.1 g) and grain yield (4119 kg ha?1) were recorded in 2013. N increased grains ear?1 (438), thousand grain weight (252 g) and grain yield (5001 kg ha?1) up to 200 kg N ha?1. Each increment of S increased grains ear?1 and other parameters up to 35 kg S ha?1, producing maximum grains ear?1 (430), thousand grain weight (245 g) and grain yield (4752 kg ha?1), while soil pH decreased from 8.06 to 7.95 with the application of 35 kg S ha?1. In the case of N and S ratios, more grains ear?1 (432), heavier thousand grains (246.7 g) and higher grain yield (4806 kg ha?1) were observed at 30:50:20 where 30% of N and S were applied at sowing, 50% at V8 and 20% at VT stage. It is concluded that 200 kg N ha?1 and 35 kg S ha?1 applied in the ratio of 30% at sowing, 50% at V8 and 20% at VT stage is recommended for obtaining a higher yield of maize hybrid Babar.  相似文献   
67.
Summary The Pl6 locus in the inbred sunflower (Helianthus annuus L.) line HA335 giving resistance to French races of downy mildew (Plasmopara halstedii (Farl.) Berl. & de Toni. was localized by molecular techniques. A bulked segregant analysis was made on the F2 progeny from a cross between this line and H52, a downy mildew susceptible line. The resistance gene in HA335 was found to have the same linked RFLP marker loci as those determined for Pl1 (resistance to race 1 in the line RHA266) on linkage group 1 of the consensus RFLP map of the cultivated sunflower. Pl1 and Pl6 thus appear either to be allelic or closely linked. The implications for sunflower breeding are discussed.  相似文献   
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Large alveolar cells of normal dog lung are rich in enzymes concerned with oxidative and synthetic pathways. In three experimental situations where ability of the lung to produce surfactant was impaired, the enzyme-rich cells were lacking or absent. Findings support the concept that these cells are sites of active metabolism, possibly including production of surfactant.  相似文献   
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