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141.
稻曲病是一种水稻穗部病害,在世界各水稻主产区均有发生,已成为世界性病害,在我国也属于水稻主要病害之一。稻曲病的发生严重影响水稻产量和稻米品质。研究其病原菌致病机制,对找寻防治药物的特异性靶标具有重要作用,可为抗病分子育种提供新的思路,为稻曲病菌防治药剂研发提供新的靶标。本文综述了稻曲病菌侵染过程、致病相关基因功能研究、水稻响应稻曲病菌侵染等方面的研究进展,提出进一步研究的策略。现有研究表明,稻曲病菌能成功侵染水稻孕穗期雄蕊的花丝引起发病。病原菌可通过抑制多个水稻免疫途径实现成功侵染;还可模仿胚珠受精激活水稻灌浆、糖代谢等途径为稻曲球的形成提供营养物质;全基因组测序完成和基因编辑技术在基因敲除中的成功应用,为稻曲病菌功能基因研究提供了很好的基础。稻曲病菌独特的侵染过程和营养利用机制是未来研究的重要方向。 相似文献
142.
143.
Alan FRANZLUEBBERS Derek HUNT Gary TELFORD Shabtai BITTMAN Quirine KETTERINGS 《农业科学与工程前沿(英文版)》2021,8(1):81-96
144.
盐碱地鱼池水化学因子与浮游植物的调查研究 总被引:3,自引:0,他引:3
对山东黄河两岸和河口地区盐碱地鱼池的水化学因子与浮游植物进行了调查研究,确认鱼池水型属ClⅢ^Na,ClⅡ^Na和ClⅠ^Na型的氯化水,pH变化在7.6-8.9之间,盐度在0.9-8之间,营养盐含量比一般淡水鱼池低,浮植物甚至不如小型水库,湖泊丰富。 相似文献
145.
亚硝酸盐在水生动物体内的吸收机制及蓄积的影响因素 总被引:8,自引:2,他引:8
亚硝酸盐是水产养殖系统中一种潜在的污染物,淡水鱼类通过鳃主动吸收亚硝酸盐,导致体内亚硝酸盐的浓度过高。海水鱼类对亚硝酸盐的敏感性较低,但仍可以通过肠和鳃吸收亚硝酸盐。影响亚硝酸盐在体内蓄积的因素很多,文章就亚硝酸盐在水生动物体内的吸收及蓄积的影响因素这2个方面进行了论述。 相似文献
146.
ABSTRACTThis study investigated the morphometrics, proximate chemical compositions, pH, total amino acid (TAA), fatty acid profile, and minerals of the processing by-products of Antarctic krill (Euphausia superba). The nutrient compositions and properties of the by-products were revealed by being compared to those of Antarctic krill muscle and the economically important species of freshwater prawns (Macrobrachium nipponense) and penaeid shrimps (Metapenaeus ensis). The by-products are worthy of utilization because of the high ratio to the total weight (65.7%). The crude protein contents in the muscle and by-products of krill are 17.4 and 11.7%, respectively. The krill proteins have higher contents of essential amino acids (EAAs). The EAAs constitute 42 and 37% of the TAAs in muscle and by-products, respectively. The krill processing by-products contain high levels of total lipid (3.3%), and polyunsaturated fatty acids constitute 34% of fatty acids with high levels of eicosapentaenoic acid (EPA; 19.08%) and docosahexaenoic acid (DHA; 10.02%). Krill meat provides considerable iron, zinc, calcium, selenium, and copper. It is imperative to lower the fluoride level (70.1 mg/kg, wet basis) in krill muscle. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) reveals that myosin heavy chain (MHC) and actin are the major proteins in muscle, and their contents vary between species. 相似文献
147.
不同饲料对哲罗鲑生长性能和营养成分的影响 总被引:1,自引:0,他引:1
在人工养殖条件下,分别投喂野生鲫鱼和人工饲料对哲罗鲑生长性能和营养成分进行比较。每组养殖实验鱼50尾,每个实验组设3个重复,试验水温10.8~16.5℃,pH值7.2~7.5,溶氧〉6.0mg/L,试验共进行56d。试验结果:野生鲫组增重率、特定生长率、肥满度、水分均显著高于人工饲料组(P〈0.05)。野生鲫组粗脂肪显著低于配合饲料组(P〈0.05)。两试验组鱼体粗蛋白、粗灰分、肌肉氨基酸含量及组成差异均不显著(P〉0.05)。野生鲫组与人工饲料组相比,野生鲫组哲罗鲑生长性能较好,鱼体成分发生改变,而肌肉氨基酸营养价值未发生变化。 相似文献
148.
Janaina Mitsue Kimpara Fabricio Ribeiro Tito Rosa Bruno de Lima Preto Wagner C Valenti 《Aquaculture Research》2011,42(9):1289-1297
We evaluated the water characteristics and particle sedimentation in Macrobrachium amazonicum (Heller 1862) grow‐out ponds supplied with a high inflow of nutrient‐rich water. Prawns were subject to different stocking and harvesting strategies: upper‐graded juveniles, lower‐graded juveniles, non‐graded juveniles+selective harvesting and traditional farming (non‐grading juveniles and total harvest only). Dissolved oxygen, afternoon N‐ammonia and N‐nitrate and soluble orthophosphate were lower in the ponds in comparison with inflow water through the rearing cycle. Ponds stocked with the upper population fraction of graded prawns showed higher turbidity, total suspended solids and total Kjeldahl nitrogen than the remaining treatments. An increase in the chemical oxygen demand:biochemical oxygen demand ratio from inlet (4.9) to pond (7.1–8.0) waters indicated a non‐readily biodegradable fraction enhancement in ponds. The sedimentation mean rate ranged from 0.08 to 0.16 mm day?1 and sediment contained >80% of organic matter. The major factors affecting pond ecosystem dynamic were the organic load (due to primary production and feed addition) and bioturbation caused by stocking larger animals. Data suggest that M. amazonicum grow‐out in ponds subjected to a high inflow of nutrient‐rich water produce changes in the water properties, huge accumulation of organic sediment at the pond bottom and non‐readily biodegradable material in the water column. However, the water quality remains suitable for aquaculture purposes. Therefore, nutrient‐rich waters, when available, may represent a source of unpaid nutrients, which may be incorporated into economically valued biomass if managed properly. 相似文献
149.
The hypothesis that the presence of fish farming zones affects the water quality and plankton communities was investigated in an Aegean Sea fish farm during February, June, September and January 2000–2001. In the spatial coverage, a total of 12 stations were sampled; three of them were reference stations. A variance analysis was applied to the measurements made at the stations near the fish farms and at the control stations. While no significant differences in concentrations of nutrients, chlorophyll a, particulate organic carbon and particulate organic nitrogen were detected between the stations and the control sites within one season, significant differences were detected between the parameter values measured except for total dissolved phosphorus and dissolved organic phosphorus at different seasons. The seasonal differences were also significant with regard to the biodiversity. Together with these temporal differences in general, there was a higher diversity of species at the control site as compared with the other stations in September, which was the key season to detection of significant changes. The most important consideration is that it is not sufficient to take the instantaneous values for the physico‐chemical variables; rather, it is necessary to monitor the biological parameters in order to define the differences in the ecosystem. 相似文献
150.