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草带在防治坡耕地土壤侵蚀中的作用 总被引:11,自引:2,他引:9
介绍了水土保持耕作法——草带间作,以及它在控制水土流失方面的作用,草带种植的几种方式,草带草种的选择等,并对这种治理坡耕地措施的发展趋势进行了展望。 相似文献
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本研究以冰草属植物中的4个品种——蒙古冰草新品系(A.mongolicum Keng)、航道冰草(A.cristatum cv.Fairway)、诺丹冰草(A.desertorum cv.Nordan)和一个种间杂种冰草——蒙农杂种冰草(A.cristatum×A.desertorum cv.Hycrest-Mengnong)为材料,分别以幼穗为外植体建立了冰草组织培养再生体系。在此基础上,以调控脯氨酸生物合成最后一步的关键酶的突变体基因P5CS为目标基因,bar基因为筛选标记基因,用基因枪法轰击幼穗诱导的愈伤组织,获得转基因植株。利用PCR方法从拟南芥(Arabidopsis thaliana)基因组DNA中分离得到了CBF4及其启动子,并对CBF4启动子进行了序列分析和初步的功能分析。 相似文献
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《中国兽医学报》2016,(9):1630-1637
疯草是世界范围分布的豆科棘豆属和黄芪属有毒植物的统称,其主要毒性成分为吲哚里西啶类生物碱——苦马豆素。放牧家畜采食疯草会发生疯草中毒病,导致瘫痪、不孕、流产、生产性能下降、死亡等,造成的经济损失巨大。波状芽管蠕孢菌是疯草中普遍存在的一类内生真菌,该菌与疯草中苦马豆素的合成和疯草的毒性紧密相关。抑制或阻断波状芽管蠕孢菌在疯草中的传播和苦马豆素合成,将有望降低或消除疯草的毒性。本文将对波状芽管蠕孢属疯草内生真菌的种属分类、与疯草毒性的关系、传播机制、SW的合成机理等方面的研究进行综述,为疯草内生真菌相关研究的开展和从控制疯草内生真菌角度防控动物疯草中毒病提供思路。 相似文献
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<正> 近十多年来,随着我国农牧业生产高速稳定的发展,具有耐旱抗病、速生高产和适口性强的多年优良牧草——红豆草引起了我国各省区的广泛重视,并在全国各地迅速推广开来。红豆草又名驴食豆,是豆科蝶形花亚科红豆草属(Onobrychis)的多年生牧草。现在栽培最多的是普通红豆草(O.viciaeffolia Scop)和高加索红豆草(O.transcaucosica Grossh)。前者 相似文献
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<正> 草层1、草层(Sward)——草本植物群体地上和地下部分的总称。它的特点是具有相对较矮的生长习性和相对连续的地面覆盖。2、草层植冠(Sward Canopy)——草本植物群体的地上部分,它涵有植物各部分的排列和分布的意义。3、牧草(Herbage)——单本植物群体的地上部分,是一种具有数量和营养价值特征的植物物质的积累,但不涵植物学组成和结构的意义。4、放牧地(Pasture)——草本植物群体的地上部分,通常有围栏为界,是放牧的一种功能单位。5、牧草量(Herbags mass)——单位土地面积的牧草总量,通常指地上的水平。但需指出,地上的水平只具一定的参考意义。 相似文献
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深山密林的草丛中,隐藏着一种伤人性命的小昆虫——草爬子。它的形状大约如红赤豆大小,一般颜色是土灰色像蓖麻籽似的,叮咬人吸足血后呈灰禇色,圆形。到深山的猎人与伐木工人都知道带毒的草爬子叮人非常厉害。虽然带毒液的草爬子只有少数,但对养蜂员来讲要非常警惕。 相似文献
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液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量的不确定度评估 总被引:1,自引:1,他引:0
采用液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量,对标准溶液、体积、质谱峰面积、浓缩过程及回收率等测定不确定度因素进行了分析,通过评定各不确定度分量及标准不确定度,得出11种β-受体激动剂的扩展不确定度在0.7 ~ 1.1 ng/mL范围内.由各因素对合成不确定度的贡献比分析可知,影响较大的因素为试验回收率及标准溶液浓度. 相似文献
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《饲料工业》2019,(18):54-58
应用电感耦合等离子-质谱技术(ICP-MS),建立饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅等元素的测定方法。对饲料样品的前处理方法、仪器工作参数和11种元素标准曲线进行优化;并以加标回收、分析方法比对和重复测试说明方法的准确性和精密性。方法在0~1 000 ng/ml范围内线性良好,仪器检出限为0.557 7~5.072 ng/ml,具有良好的精密度,其回收率在88.1%~104.4%之间,相对标准偏差小于5.0%。同时与原子吸收和原子荧光方法进行比对,测定结果相近。所建立的方法简单、快速,可替代原子吸收和原子荧光方法测定饲料中的11种金属元素,为饲料的质量控制提供理想的元素分析方法。 相似文献
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In experiment 1, 6 pregnant mares received a concentrate that contained a trace mineral premix that provided 14.3 mg Cu, 40 mg Zn, 28 mg Fe, 28 mg Mn, 0.08 mg Co, 0.16 mg I, and 0.16 mg Se/kg concentrate (group A). Seven mares received the same concentrate plus 502 mg Zn and 127 mg Cu once daily (group B). No differences (P > .05) in foal growth data, or Cu, Zn, and Fe concentrations of mare milk, mare serum, or foal serum were observed. In experiment 2, 6 pregnant mares received the same concentrate as group A (group C), and 8 mares received the same concentrate fortified with 4× the trace mineral premix (group D). Group C mares had higher serum Zn concentration at 1 day (P < 0.01) and 56 days (P < 0.04). Group C mares had higher milk Fe concentration at 28 days (P < .01), and group D mares had higher milk Cu concentration at 56 days (P < .01). Group C foals had higher serum Cu concentration at 14 days (P < .03). The results from this study provide no evidence to indicate that supplementing late gestating and lactating mares with higher dietary trace mineral levels than those recommended currently by NRC has any influence on foal growth and development, or on the Cu, Zn, and Fe concentrations of the mare milk, mare serum, or foal serum. 相似文献
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Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size. 相似文献
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枇杷是原产于中国的亚热带果树,是一种药食同源的保健水果,其栽培历史悠久。我国幅员辽阔,生态环境多样,孕育了世界上最多的枇杷种质资源。本文综述了我国枇杷属植物种质资源的收集与保存、种质交流、种质创新与利用的研究现状、问题分析;对未来发展提出意见,要努力创制“种源惟一,节肥、节水,省工、省力、省药”的“一源两节三省”品种与配套栽培技术,精准保护知识产权。对种源的知识产权保护要织密物防、技防的网络,诉案须有保护对象唯一的技术身份数据佐证,独具排他性。综述,本研究为枇杷种质资源的发展创制和产业发展提供决策参考。 相似文献