水保综合治理已成为新县经济发展的重要支撑

新县是一个集“老、边、贫”为一体的国家级山区贫困县,水土流失面积达1 411 km2,治理前年均土壤侵蚀模数达3 340 t/km2。截至2002年,全县初步完成水土保持综合治理面积751 km2,年均土壤侵蚀模数下降到1 250 t/km2。通过综合治理,新增有效灌溉面积12.6万亩,新增旱涝保收田8.4万亩,兴修道路600多km,农村解决人畜饮水5 000多处,75%的农户用上了自来水,65%的农户翻盖了砖瓦房,极大地改变了农村面貌,已有90%以上的农民解决了温饱、摆脱了贫困,开始走向致富道路。针对存在的问题,提出了加快该县水土保持事业发展的建议。     

闭锁群体BLUP选择下遗传方差和近交系数的变化

采用计算机随机模拟方法模拟了在一个闭锁群体内连续对单个性状进行 1 5个世代选择的情况。选择过程中世代不重叠 ,每个世代的种畜根据动物模型最佳线性无偏预测 (BLUP)法估计的育种值进行选留 ,并在此基础上系统地比较了不同群体规模、公母比例和性状遗传力对群体遗传方差和近交系数变化的影响。结果表明 ,扩大育种群规模、增加公畜比例以及对低遗传力性状进行选择时 ,群体遗传方差降低的速度和近交系数上升的速度会更慢 ,在长期选择时可望获得更大的持续进展和适宜的近交增量     

Effects of non-excitatory electric stimulation on cardiac function in normal and infarcted heart rabbits and it's regional effect on myocardium

AIM: To investigate the influences of electric stimulation applied during the absolute refractory period (ARP) on the cardiac function of normal rabbits and rabbits after myocardial infarction (MI) and to observe the regional effects of this electric stimulation. METHODS: 64 rabbits were randomly assigned to normal and MI groups and each group was then divided into the anterior and posterior groups. A thoracotomy was performed 4 weeks after MI in rabbits. One set of electrodes was inserted into the anterior and posterior wall of left ventricle of the anterior and posterior groups, respectively. Current pulses were delivered during the ARP (called CCM) during sinus rhythm in rabbits. The left ventricular systolic pressure (LVSP) and the left ventricular end diastolic pressure(LVEDP) as well as maximum positive and negative left ventricular pressure change (±dp/dt_max) were observed. RESULTS: In the normal and MI groups, LVSP, +dp/dt_max significantly increased, and LVEDP, -dp/dt_max were reduced during CCM stimulation compared with the baseline (P<0.05). In the normal rabbits, electric stimulation in the anterior group improved the cardiac function more significantly than that in the posterior group (P<0.05). In the MI rabbits, there was no difference between the anterior and the posterior groups (P>0.05). CONCLUSION: Electric stimulation delivered during the ARP significantly enhances the contractility and the relaxation of myocardium in normal rabbits and rabbits after MI, and the effects of CCM stimulation on heart are regional.     

鼠层粘蛋白α5链E3、LG4、LG5片段的克隆及表达

从鼠的肝脏组织中提取总 RNA,采用 RT- PCR获得了鼠层粘蛋白 ( laminin)α5链的 E3 ( L G4 - 5)、L G4 和 L G5等 3个基因片段 ,与 NCBI数据库参考序列相比 ,同源性在 99%以上。将 E3 ( L G4 ,5)、L G4 和 L G5定向克隆到原核高效表达载体 Pet- 2 8a中 ,构建 Pet- 2 8a- E3 、Pet- 2 8a- L G4 、Pet- 2 8a- L G5等 3个原核表达质粒。将表达质粒转化表达受体菌 BL2 1中 ,IPTG诱导表达。收集菌液进行 SDS- PAGE电泳、Western- blotting分析 ,结果显示 ,这 3段基因在原核细胞中成功表达 ,薄层扫描显示表达蛋白占细胞总蛋白的 2 0 %以上。大量提取包涵体 ,纯化后免疫家兔 ,8周后得多克隆抗体 ,间接 EL ISA在抗体稀释到 1∶ 1 2 80 0时仍为阳性     

以催乳素受体基因作为撒坝猪部分生产性能候选基因的研究

此文运用PCR-RFLP技术检测催乳素受体(PRLR)基因在撒坝猪群体中的多态性分布,并采用最小二乘分析模型初步统计分析基因多态性与部分生产性能的相关性。结果表明,PRLR基因等位基因B及其基因型BB在群体中占优势,频率分别为0.6594和0.4438;PRLR基因在群体中处于Hardy-Weinberg平衡状态;头胎繁殖性状有利等位基因B对生长性状无不利影响。     

部分小麦品种(系)及高代材料的高分子量谷蛋白亚基组成分析

为在春小麦品质育种中合理利用种质资源,采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)技术,对62份引进品种(系)和58份春小麦高代材料进行高分子量谷蛋白亚基(HMW-GS)组成分析.结果表明,供试材料1、7 8、5 10亚基及其组合的频率最高.其中引进材料Glu-A1位点的三种等位变异中,1亚基频率为43.5%;Glu-B1位点的六种等位变异中,7 8亚基的频率为37.1%,其次是17 18,占22.6 %;Glu-D1位点的三种等位变异中,5 10占61.3%,2 12占37.1%,还发现1份材料具有13 16亚基.在春小麦高代材料中,Glu-A1位点上1亚基的频率为63.8%;Glu-B1位点有五种等位变异,以7 8最多,为48.3%;Glu-D1位点有两种等位变异,5 10最多,占79.3%.参试材料的HMW-GS组合类型有21种,含5 10亚基的组合占全部组合的61.9%,其中1/7 8/5 10亚基组合占材料总数的23.3%.1/17 18/ 5 10/2*/7 8/5 10、2*/17 18/5 10、null/7 8/5 10和null/17 18/5 10五种组合的频率依次为5.0%、3.3%、5.8%、5.8%和1.7%.     

Involvement of the autophagy-related gene BdATG8 in development and pathogenicity in Botryosphaeria dothidea

Botryosphaeria dothidea is a destructive fungal pathogen that causes Botryosphaeria canker and fruit ring rot on apple worldwide. Autophagy is a process of self-degradation that maintains intracellular homeostasis via lysosomal pathway.To date, the biological role of autophagy in B. dothidea remains unknown. In this study, we identified and characterized the autophagy-related gene BdATG8 in B. dothidea. BdATG8 was able to restore the defect in nitrogen starvation tolerance of Saccharomyces cerev...     

EMS诱变玉米自交系郑58后代变异分析及应用评价

种子是农业的“芯片”,是保障粮食安全的根本,农业种质资源又被称为“种业芯片”。因此,引进、创制和丰富种质资源是攻克“卡脖子”技术的关键,通过人工诱变是种质资源创新的一个重要途径。利用0.67 mg/L EMS诱变玉米自交系郑58花粉,构建1 650个株系的玉米突变体库,从M₂和M₃后代筛选到包括生育期、株型、叶型、穗型、粒型、叶色、轴色、育性等多个农艺性状突变体,表型变异率约为9.6%。结果表明,具有育种应用潜能的代表性材料有Z330、Z641和Z1433等,可供用于选育矮秆、低穗位、耐密植、抗倒伏型新品种;Z636、Z848和Z930等新种质材料可用于测配或改良玉米穗型、粒型、轴色、粒色及品质性状。     

基于微润灌溉大棚番茄对施肥运筹的响应

为探究微润灌溉下不同施肥运筹对大棚番茄生长的影响,将番茄定植于大棚内的种植箱中,设置施肥浓度分别为200 mg/L(N1:全生育期浓度为200 mg/L)、200～400 mg/L(N2:苗期浓度为200 mg/L,结果期、成熟期为400 mg/L)、400 mg/L(N3:全生育期浓度为400 mg/L)、400～8...