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911.
向大豆导入几丁质酶基因的初步研究 总被引:32,自引:8,他引:24
以根癌农杆菌的Ti质粒为介导,将抗真菌病的几丁质酶基因,导入默经江省栽培大豆一东农37号,吉林28号等14个品种。从子叶节和下胚轴诱导出丛生芽,并再生植株,经PCR和DNA分子杂交检测,经PCR和DNA分子杂交检测的113株大豆幼苗中,有7株呈阳性反应,证明几丁质酶基因已导入并整合到大豆的基因组中。 相似文献
912.
种瓣及密度对大蒜产量的影响 总被引:1,自引:0,他引:1
采用二次正交通用旋转设计,进行了种辩大小与种植密度对大蒜产量影响的研究,建立了大蒜产量与种植密度及种瓣大小间的二元二次数学模型。通过模型解析得出,种植密度对产量的影响大于种瓣大小,但密度对单株产量的贡献为负值。通过计算机模拟试验,得出本试验条件下,获得30000kg/hm2以上产量的种植密度为52.95~63.45万株/hm2、种瓣大小为4.9~7.0g;;单株产量大于50g的种植密度为34.05~4.55万株/hm2、种瓣大小4.9~7.0g。 相似文献
913.
K. Madriz-Ordeñana R. Rojas-Montero T. Lundsgaard P. Ramírez H. Thordal-Christensen & D.B. Collinge 《Plant pathology》2000,49(2):302-307
Maize rayado fino marafivirus (MRFV) was mechanically transmitted to kernels of three Costa Rican maize cultivars by the vascular puncture technique. A transmission rate of up to 43.2% was obtained for cultivar HC-57. The rate of MRFV transmission to maize was possibly affected by the morphology of the kernel, which may influence physical access to the vascular tissue after water imbibition. Transmission to maize was confirmed by western blot and immunosorbent electron microscopy. By slight modifications of the procedure, MRFV was also transmitted to barley. This is the first report of MRFV infecting a species outside the supertribe Andropogonodae. Virus infection and replication in barley were confirmed by RT-PCR detection of MRFV RNA and by detection of the virus by ELISA. 相似文献
914.
915.
PJ Waller G Bernes SM Thamsborg A Sukura SH Richter K Ingebrigtsen J H?glund 《Acta veterinaria Scandinavica》2001,42(1):31-44
Preparations derived from plants were the original therapeutic interventions used by man to control diseases (including parasites), both within humans and livestock. Development of herbal products depended upon local botanical flora with the result that different remedies tended to develop in different parts of the world. Nevertheless, in some instances, the same or related plants were used over wide geographic regions, which also was the result of communication and/or the importation of plant material of high repute. Thus, the Nordic countries have an ancient, rich and diverse history of plant derived anthelmintic medications for human and animal use. Although some of the more commonly used herbal de-wormers were derived from imported plants, or their products, many are from endemic plants or those that thrive in the Scandinavian environment. With the advent of the modern chemotherapeutic era, and the discovery, development and marketing of a seemingly unlimited variety of highly efficacious, safe synthetic chemicals with very wide spectra of activities, herbal remedies virtually disappeared from the consciousness--at least in the Western world. This attitude is now rapidly changing. There is a widespread resurgence in natural product medication, driven by major threats posed by multi-resistant pest, or disease, organisms and the diminishing public perceptions that synthetic chemicals are the panacea to health and disease control. This review attempts to provide a comprehensive account of the depth of historical Nordic information available on herbal de-wormers, with emphasis on livestock and to provide some insights on potentially rewarding areas of "re-discovery" and scientific evaluation in this field. 相似文献
916.
Walker MC Hill RC Guilford WG Scott KC Jones GL Buergelt CD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(5):463-466
A postprandial ammonia tolerance test (PPATT) was performed on normal dogs and dogs with signs that suggested they may have liver disease. All dogs underwent transcolonic scintigraphy, liver biopsy, or both and were assigned to extrahepatic disease, primary hepatocellular, and congenital portosystemic vascular anomalies (PSVA) groups. Each dog was fed a chicken and rice diet providing 25% of its estimated daily metabolizable energy requirement (MER) as an ammonia challenge. This is practical in patients with liver disease because ammonium chloride administration often causes vomiting or ammonia toxicity. Venous ammonia concentrations were measured before feeding and every 2 hours after feeding for 8 hours. No difference in mean ammonia concentrations between dogs with extrahepatic disease and control dogs was found. Therefore, the specificity of the PPATT was 100%. Dogs with hepatocellular disease showed no change in mean ammonia concentration at any time point, before or after feeding, but sensitivity was greatest when venous ammonia was measured 6 hours after feeding (sensitivity before feeding, 28%, and after feeding, 36%). Among dogs with congenital PSVA, mean ammonia concentrations were higher than the reference range at all time points before and after feeding, and peak mean ammonia concentration occurred 6 hours after feeding. In this group, the sensitivity of the PPATT was 81% before feeding and 91% 6 hours after feeding. This study demonstrates that the measurement of venous ammonia concentration is a useful test to detect congenital PSVA, and the sensitivity of the test may be improved by sampling 6 hours after feeding. The PPATT has poor sensitivity in detecting primary hepatocellular disease. 相似文献
917.
蜡蚧轮枝菌防治植物病虫害研究进展 总被引:4,自引:0,他引:4
蜡蚧轮枝菌在蔬菜病虫害防治中有很大开发潜力。就蜡蚧轮枝菌的致病性、环境条件对其生长的影响、储藏期存活率及在生产中应用的概况的研究进展进行了综述。研究进展表明,该种真菌既可以防治粉虱、蚜虫、蓟马等蔬菜害虫,又可以防治蔬菜的白粉病、锈病等。 相似文献
918.
Germination response of Orobanche seeds subjected to conditioning temperature, water potential and growth regulator treatments 总被引:7,自引:0,他引:7
W J SONG W J ZHOU Z L JIN D D CAO D M JOEL† Y TAKEUCHI‡ & K YONEYAMA‡ 《Weed Research》2005,45(6):467-476
Broomrapes (Orobanche spp.) are parasitic weeds that cause significant losses of crop yield. Experiments were conducted to investigate the seed response to the artificial germination stimulant GR24 in three species of Orobanche subjected to preconditioning under various temperatures, water potentials and with plant growth regulators. The highest germination percentages were observed in Orobanche ramosa, Orobanche aegyptiaca and Orobanche minor seeds conditioned at 18°C for 7 days followed by germination stimulation at 18°C. With the increase of the conditioning period (7, 14, 21 and 28 days), the germination percentage of O. ramosa and O. aegyptiaca progressively decreased. When conditioned at −2 MPa, the germination percentage was lower than at 0 and −1 MPa, especially at 13 and 28°C. Orobanche minor seeds could retain relatively high germination if conditioned at 18, 23 or 28°C, even after significantly extended conditioning periods (up to 84 days). GA3 (30–100 mg L−1), norflurazon and fluridone (10–100 mg L−1), and brassinolide (0.5–1.0 mg L−1) increased seed germination, while 0.01 mg L−1 uniconazole significantly reduced germination rates of all three Orobanche spp. The promotional effects of GA3 and norflurazon and the inhibitory effect of uniconazole were evident, even when they were treated for 3 days. Germination of Orobanche seeds was much lower when the unconditioned seeds were directly exposed to GR24 at 10−6 m . This early GR24-induced inhibition was however alleviated or even eliminated by the inclusion of GA3 or norflurazon (10–50 mg L−1) in the conditioning medium. On the contrary, the inclusion of uniconazole increased the inhibitory effect of GR24, particularly in the case of O. ramosa. 相似文献
919.
Xanthomonas axonopodis pv. glycines ( Xag ) causes bacterial pustule disease which can significantly reduce the production of soybean. A collection of 26 isolates of Xag from different soybean-production areas of Thailand was shown to differ with regard to aggressiveness on soybean. They also differed in their ability to induce a hypersensitive response (HR) on four cultivars of tobacco and on other plant species including pepper, tomato, cucumber, pea and sesame. Tomato was most sensitive to HR induction by Xag . Isolate KU-P-34017 caused an HR on all the plant species tested. The minimal concentration of KU-P-34017 needed to induce HR on tobacco was approximately 5 × 108 CFU mL−1 . A bacterium–plant interaction period of at least 2·5 h was necessary for HR, and different temperatures, relative humidity and light periods did not affect HR development. Inhibitors of eukaryotic metabolism, including cobalt chloride, lanthanum chloride and sodium orthovanadate (completely), and cycloheximide (partially) blocked the HR on tobacco, indicating the association of an active plant response. In contrast, the HR on tomato was inhibited only by cobalt chloride. 相似文献
920.
用PDA培养基平板法测定了0.4%OS-诱抗剂水剂对水稻纹枯病菌、小麦纹枯病菌、油菜菌核病菌、辣椒立枯病菌、瓜类绵腐病菌、黄瓜枯萎病菌的生物活性,其EC50值分别为34.56、59.33、33.17、85.92、91.91、122.87μg/mL,OS-诱抗剂对水稻纹枯病、油菜菌核病较好。高效液相色谱分析表明,经OS-诱抗剂处理后的植物提取液中酚类物质的种类和含量相对于对照有明显的变化,说明OS-诱抗剂对植物的防病作用可能是促使植物体内产生了酚类抗病物质。 相似文献