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传统的桑园建设都要经过桑苗培植,栽桑成林,一般需要3～4年方可成园,不仅成园慢而且投资成本大,一直制约蚕桑发展的快速发展。近年来我市蚕桑科技人员经过反复实践.总结了一套桑树快速成园的捷径——嫁接体营养钵温床育苗快速成园技术。桑树 相似文献
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7个新桑品种的生物鉴定 总被引：1，自引：0，他引：1
<正> 长期以来,吴江市的桑树品种一直以湖桑32号为主,实践证明,桑品种的限制已成为我市蚕桑生产持续发展的“瓶颈”。为了推广产量、质量和主要抗性优于湖桑32号的替代品种,从1999年开始我们引进了农桑12、14号等多对新品种,建立品比园区,进行筛选试验。2002年春蚕期开展了生物鉴定试验。现将结果初报如下。 相似文献
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<正> 为实现早中晚生桑品种搭配栽植,满足蚕不同发育时期对饲料的需求,以提高蚕桑产量和品质,1997年从浙江省农科院蚕桑所引进农桑系列桑品种进行栽培养蚕试验,其中农桑8号等三个品种表现较好。现简报初步结果。 1 材料及方法 为快速获得桑品种的栽培适应性表现成绩,于1998年1月在贯山乡八村程子钰的老龄桑园(1500株/667m~2),采用锯桩芽接法嫁接农桑8号(早生)、育2号(早生)、农桑12 相似文献
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<正>近几年来,蚕桑产业效益好,一些新育成的桑树品种因其高产优质性能,各地都竞相引进种植,现浙江省新育成的品种主要有农桑系列品种(农桑8号、农桑10号、农桑12号、农桑14号)、盛东1号、大中华、海宁桑等,这些品种的推广应用,促进了我国蚕丝业快速发展。但是由于现在桑苗市场上,优质桑苗新品种供不应求,尤其是去冬今春,在我国最主要的桑苗主产区——浙江省海宁、桐乡两市,桑树新品 相似文献
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云南省蚕区具有明显的高原立体气候,选育适应云南蚕区种植的优质、高产桑树新品种,对于云南蚕桑产业的可持续发展具有重要意义。利用云南蚕区现行优良桑树品种及优异桑种质资源作为亲本材料,采用杂交和化学诱导染色体加倍的方法,育成人工同源四倍体桑树新品种云桑5号。新品种于2015—2017年在云南省多点进行区域适应性种植试验,在草坝镇试验点的单位面积产叶量比对照桑品种湖桑32号和农桑14号分别增产42.63%和19.01%,桑叶养蚕的万头蚕产茧量和茧层率与2个对照品种比较均无显著差异;新品种在永仁县、巧家县、陆良县、楚雄市和鹤庆县按照当地的栽植模式其产叶量较农桑14号高出16.08%~18.75%。新品种还具有发芽期早、发条力强、生长旺盛、叶片肥厚等特性,但对桑褐斑病和桑白粉病的抵抗力稍弱,需要及时采摘适熟叶以降低病害的影响。 相似文献
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《中国蚕业》2020,(2)
为探讨非杂交桑品种嫁接苗采用高密度草本式栽培的丰产性能和养蚕效果,利用发条能力较强的农桑14号嫁接桑进行了高密度草本式栽培建立桑园(简称农桑14号草本桑,90 000株/hm~2)的试验,以桂桑优12号杂交桑草本式栽培建立桑园(简称桂桑优12号草本桑,105 000株/hm~2)和育71-1嫁接桑普通栽植低干养成建立桑园(简称育71-1普栽桑,24 000株/hm~2)为对照,调查了3种桑园第1～5年的产叶量指标,并进行了养蚕鉴定。结果表明,建桑园第1～3年,试验区农桑14号草本桑的片叶产量比对照区桂桑优12号草本桑低10.42%～14.87%,但第4年和第5年,农桑14号草本桑的片叶产量分别比桂桑优12号草本桑提高8.81%和5.18%,5年单株总产叶量农桑14号草本桑比桂桑优12号草本桑高16.04%,5年合计经济系数(片叶质量与条叶总质量之比)农桑14号草本桑比桂桑优12号草本桑高8.87%。无论是农桑14号草本桑还是桂桑优12号草本桑,各年度产叶量均高于育71-1普栽桑。建园第1年(2013年)秋蚕期和建园第2年(2014年)春蚕期的养蚕试验结果表明,农桑14号草本桑条桑育成绩均优于桂桑优12号草本桑,与育71-1普栽桑片叶育的效果相当。本试验结果说明,利用耐剪伐的嫁接桑品种,采用高密度草本式栽培可以实现速生丰产和桑叶优质。 相似文献
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农桑8号是浙江省农科院蚕桑所1980年用异地人工有性杂交方法育成的桑树新品种,其母本为日本引进桑品种的一之濑,父本是广东品种伦教109号。农桑8号1985年进入省第二期桑品种区域性鉴定,同时参加该期鉴定的桑树新品种还有之江2号、之江3号、农桑9号、激桐5号和双头桑等5个品种,用荷叶白作对照种,在本省平原、丘陵、溪滩、海涂4种不同土壤类型的10个点进行特征特性、生长发育、产质量及抗病性的观察与鉴定。 相似文献
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蚕桑产业是淳安农村经济的主导产业,是现阶段农民家庭经济收入的主要来源之一.全县现有2.4万户蚕农从事蚕桑生产,受益农业人口近8万,有桑园4520hm2,年产茧5000t,蚕桑总产值1.45亿元.但由于2000年以前推广的桑品种都是湖桑,且多数种在高山薄地上,树龄老化,单位面积产茧量较低.要提高蚕桑单位面积产茧量,要做强做大蚕桑产业,推广优质高产的桑树新品种是一项关键的措施.由于农桑系列品种可大幅度提高单位面积桑园产茧量和经济效益,淳安县在2001～2003年大力引进推广农桑12、14号新品种. 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献