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81.
R44型直升机喷雾防治柑橘木虱的效果初报 总被引:1,自引:0,他引:1
大区域内实施柑橘木虱统防统治是控制柑橘黄龙病的关键措施,也是难点。本试验研究R44型直升机施药防治柑橘木虱的可行性和效果。在连片柑橘园,利用R44型直升机喷洒30%噻虫嗪悬浮剂防治柑橘木虱,施药3、7和10d后,柑橘木虱的虫口减退率分别为84.2%、84.8%和85.0%,防治效果分别为85.3%、87.7%和89.6%;对果树无损伤。试验结果表明,利用R44直升机施药进行柑橘木虱大面积防治可行有效,是一种省工、快速、高效的施药方式,值得大面积推广应用。 相似文献
82.
小麦品种川麦107对条锈病成株抗性的QTL定位 总被引:1,自引:0,他引:1
【目的】发掘川麦107中的条锈病成株抗性基因及与其紧密连锁的分子标记,为小麦持久抗性育种提供基因和分子标记辅助选择工具。【方法】在墨西哥国际玉米小麦改良中心(CIMMYT)Toluca试验站、中国成都和雅安3个环境下,对川麦107/Avocet-YrA组合的F5代重组自交系(recombinant inbred line,RIL)群体进行了小麦条锈病成株抗性鉴定,在此基础上利用SSR标记和复合区间作图法对成株抗性基因进行定位。【结果】在1B染色体长臂远端的Xcwem32和Xgwm818位点之间(连锁距离3.9cM)检测到1个主效QTL,暂定名为QYr.saas-1BL。该主效QTL在3个试验环境下分别解释19.3%、16.9%和27.4%的表型变异。【结论】QYr.saas-1BL是川麦107中对条锈病有持久抗性的成株抗性QTL。 相似文献
83.
为筛选甘蔗无根试管苗最适种植基质,提高其成活率,降低生产成本,以甘蔗新品种桂糖44号为试材,采用单因素试验研究不同基质对其无根试管苗瓶外生根成活率的影响。结果表明:桂糖44号无根试管苗在不同基质上成活率依次为70%田园土+30%河沙(T_4)田园土(T_3)河沙(T_5)70%黄泥+30%河沙(T_2)黄泥土(T_1)高肥力有机质(T_6);生长速依次为T_6T_4T_3T_2T_1T_5;发根快慢依次为T_5T_4T_2T_3T_1T_6,但发根时间差异不大;不同基质中以高肥力有机质最容易发霉,其次是田园土,黄泥和河沙不易发霉。甘蔗无根试管苗最适种植基质为70%黄泥+30%河沙。 相似文献
84.
Manuel Alvarez-Rodriguez Maria Ntzouni Dominic Wright Kabirul Islam Khan Manel López-Béjar Cristina A. Martinez Heriberto Rodriguez-Martinez 《Reproduction in domestic animals》2020,55(3):293-300
The avian seminal fluid (SF) is a protein-rich fluid, derived from the testis, the rudimentary epididymis and, finally, from the cloacal gland. The SF interacts with spermatozoa and the inner cell lining of the female genital tract, to modulate sperm functions and female immune responsiveness. Its complex proteome might either be free or linked to extracellular vesicles (EVs) as it is the case in mammals, where EVs depict the tetraspanin CD9; and where those EVs derived from the epididymis (epididymosomes) also present the receptor CD44. In the present study, sperm-free SF from Red Jungle Fowl, White Leghorn and an advanced intercross (AIL, 12th generation) were studied using flow cytometry of the membrane marker tetraspanin CD9, Western blotting of the membrane receptor CD44 and electron microscopy in non-enriched (whole SF) or enriched fractions obtained by precipitation using a commercial kit (Total Exosome Precipitation Solution). Neither CD9- nor CD44 could be detected, and the ultrastructure confirmed the relative absence of EVs, raising the possibility that avian SF interacts differently with the female genitalia as compared to the seminal plasma of mammals. 相似文献
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87.
棉铃虫核型多角体病毒(HearNPV)ORF44是一个功能未知的基因,研究对HearNPV ORF44基因的序列及原核表达进行了初步研究。结果表明,HearNPV ORF44基因全长1 137 nt,编码378aa,预测编码蛋白分子量为42.7 ku。序列分析显示,ORF44具有双相启动子特征序列,同时兼有杆状病毒早期和晚期基因转录启动子特征序列。ORF44的推导氨基酸序列中含有1个强跨膜螺旋区域,32个磷酸化位点和4个糖基化位点。除HzNPVORF45外,未发现与ORF44氨基酸同源性高于30%的基因。构建了pET-44表达载体,并在大肠杆菌BL21中得到了高效表达,表达的融合蛋白分子量为44 ku,与预测编码蛋白分子量大小相符。序列分析结果表明,ORF44是He-arNPV的一个特有基因,ORF44融合蛋白的成功表达为深入研究HearNPV ORF44奠定了基础。 相似文献
88.
优质强筋小麦品种川麦36自育成以来对条锈病成株期抗性为高抗-免疫,是一份重要优质抗病资源。为研究川麦36抗条锈基因组成及遗传特点,本研究用条锈病条中30(CY30)、条中31(CY31)和条中32(CY32)混合菌种对抗感病双亲、F1、F2、BC1和BC2进行人工接种并做抗性遗传分析。根据F1及BC1、BC2的抗感反应确定抗性基因的显隐性,根据F2的抗感分离比例,经卡方测验确定抗性基因对数。结果表明,川麦36对条锈病条中30(CY30)、条中31(CY31)和条中32(CY32)混合菌种的成株期抗性是由1对显性基因控制。 相似文献
89.
The aim of this study was to investigate development over time of the surface expression of CD44 on macrophages during an inflammatory response of bovine mammary gland. Intramammary instillation of muramyl dipeptide (MDP) and lipopolysaccharide (LPS) resulted in a significant increase in the total count of CD44+ non-vacuolised macrophages (NMAC) after 24 h. During resolution of the inflammatory response, there was observed a gradual decrease in the total count CD44+ NMAC. The lower total count and proportion of CD44 + vacuolised macrophages (VMAC) was observed as the effect of MDP and LPS at 24 h after induction (P < 0.01). During resolution, the total count and proportion of CD44 + VMAC increased. We have demonstrated CD44 receptor is expressed during the inflammatory response caused by LPS and MDP and the effect of these components on CD44 expression was particularly evident during initiation of the inflammatory response. High expression of CD44 in resolution of inflammatory response may relate to macrophages´ involvement in the processes leading to restitution of injured tissues. 相似文献
90.
Madrazo J García-Fernández RA García-Iglesias MJ Durán AJ Espinosa J Pérez-Martínez C 《Veterinary journal (London, England : 1997)》2009,180(3):371-376
CD44 is an adhesion molecule implicated in the progression of human breast cancer. The purpose of this study was to describe CD44 antigen expression in canine mammary carcinomas and to evaluate its prognostic significance in relation to other clinico-pathological variables.A reduction in CD44 expression was significantly related to variables such as tumour size and adherence to underlying tissues but was not related to tumour location or to ulceration of the overlying skin. Complex (grade I) and anaplastic (grade III) carcinomas exhibited more intense expression of this antigen than did some tubulopapillary and most solid carcinomas (grade II). Although reduced CD44 expression was associated with infiltrative growth and vascular invasion in solid carcinomas, intense expression was also observed in anaplastic tumours. Although overall these findings suggest a role for this adhesion factor in canine mammary tumour development and progression, the complexity and apparently paradoxical nature of some of the findings currently limit the use of this immunohistochemical marker as a prognostic indicator. 相似文献