一种在光镜下观察花粉滚动和立体形状的制片方法

介绍利用油镜油观察花粉滚动和立体形状的制片方法,以及将普通显微镜(即明场显微镜)改制成暗场显微镜的方法和观察结果。将植物花粉均匀地撒在载玻片上,盖上盖玻片,用铅笔上的橡皮头等软物轻敲1~2下,然后在盖玻片外侧(或角端)滴上1小滴油镜油,油镜油沿着载玻片与盖玻片之间的缝隙向内扩散,制片完成并立即进行显微镜观察。利用油镜油对花粉进行制片,比较容易在40倍物镜下直观地观察和记录花粉的滚动过程和立体形状、层次结构、表面纹饰。将显微镜进行一些结构改建,可以一镜多用。随着光学显微镜的不断升级换代,光镜在观察花粉形状和结构信息等方面,将具有越来越多电镜无法取代的优势。     

Cytoplasmic substitution inSolanum. I. Seed production,germination, and sterilities of reciprocal backcross generations

Summary Genes ofSolanum tuberosum L. ssp.tuberosum were introduced into cytoplasm ofS. tuberosum ssp.andigena (Juz. & Buk.) Hawkes andS. phureja Juz. & Buk. to reduce cytoplasmic sterilities. Alleles that influenced berry set and seed content produced differences between reciprocal progenies. Their expressions were interpreted in terms of genes of the maternal and/or paternal parents. When the ssp.andigena genotype was introduced from the maternal parent if favoured high berry set and low seed number. Maternal ssp.tuberosum favoured lower berry set and higher seed number. The source ofS. phureja cytoplasm, aS. phureja×S. chacoense F₁, used as maternal parent favoured lower berry and seed set. During successive backcrosses progeny expressions approached those of the recurrent ssp.tuberosum pollen parents. A low level of pollen sterility occurred in BC₂ plants, unrelated to direction of cross or cytoplasmic factors. By BC₄, seed set and fertility were as good as ssp.tuberosum, and recurrent backcrossing could be terminated without loss of seed production or fertility. Pennsylvania Agricultural Experiment Station Journal Series No. 7493.     

Detection of hybrids between masu salmon <Emphasis Type="Italic">Oncorhynchus masou masou</Emphasis> and amago salmon <Emphasis Type="Italic">O. m. ishikawae</Emphasis> occurred in the Jinzu River using a random amplified polymorphic DNA technique

Identification of masu salmon Oncorhynchus masou masou and amago salmon O. m. ishikawae was accomplished using a random amplified polymorphic DNA (RAPD) technique. Of 80 primers screened, three primers amplified subspecies-specific fragments (OPA11-1095 ^*, OPB5-1618^* and OPD5-2038 ^*). Based on fragment patterns, 33 hybrids were detected among 150 upstream-migrating individuals in the Jinzu River, central Japan, a long-time habitat of masu salmon, to which amago salmon were recently introduced. All of the individuals examined in the 2000–2002 cohorts were identified as F ₁ and F _x as well as pure masu and amago forms. These results indicated continuing hybridization, the genetic pollution of the native masu salmon population by amago salmon possibly being a serious problem in the Jinzu River. Both standard length and body weight in F ₁ hybrids tended to be less than in pure masu salmon. However, F _x hybrids showed similar body sizes to masu salmon.     

回交鲤与回交荷包红鲤染色体核型的比较分析

在23～25℃下,给平均体质量104.2g和106.8g的回交鲤（鲤鲫杂交♀×鲤♂）和回交荷包红鲤（鲤鲫杂交♀×荷包红鲤♂）胸腔注射植物凝集素（PHA）和秋水仙素,然后观察对比了染色体核型,探讨回交后代的染色体遗传。结果表明,两种鲤鲫杂交回交子代染色体组均由150条染色体组成,按着丝粒位置染色体组型可分为四组,每个染色体小组均由三条同源染色体组成。其中,回交鲤染色体数目为3n=150,染色体臂数NF=234,其核型公式为：3n=60m＋24sm＋36st＋30t;回交荷包红鲤的染色体数目为3n=150,染色体臂数NF=252,其核型公式为：3n=66m＋36sm＋18st＋30t。     

渐开线花键轴冷滚轧工艺试验

根据啮合原理,运用等升距螺旋面的形成理论设计了滚轧轮理论廓形,采用试验计算法对滚轧轮的理论廓形进行修正;对滚轧轮的材料选择、热处理工艺进行了输入的研究,根据修正后的滚轧轮廓形制造出滚轧轮;进行了渐开线花键轴冷滚轧工艺等方面的研究,设计了冷滚轧渐开线花键轴的数控程序,进行了实际零件加工试验。结果证明:这套从滚轧轮设计、材料选择、制造到渐开线花键轴加工工艺设计理论的正确性。为自主设计制造冷滚轧滚轧轮提供了可行的方案,为冷滚轧渐开线花键轴提供了加工工艺规范。     

小麦抗赤霉病3B-QTL和6B-QTL的遗传互作模式分析

为明确来自抗赤霉病的小麦品种望水白的2个主效抗扩展3B-QTL和6B-QTL的抗性遗传和互作模式,基于分子标记辅助选择方法,构建了回交分离群体,以病小穗数(NDS)和病轴长(LDR)为鉴定指标,采用单花滴注接种法对携带3B-QTL和6B-QTL的BC_3F_1、BC_3F_2、BC_3F_3世代以及抗感对照进行了抗赤霉病扩展的表型鉴定和评价。结果表明,3B-QTL和6B-QTL在烟农19和矮抗58不同的背景中,杂合基因型与纯合望水白基因型之间的NDS和LDR差异显著;携带3B-QTL和6B-QTL株系的抗扩展性与只含有单个3B-QTL的株系无显著差异,但显著高于只携带单个6B-QTL株系的抗性,抗感分离比经卡方检验符合4∶3∶9的分离比例,遵循2个独立孟德尔遗传因子控制的隐性遗传模式,且3B-QTL隐性上位于6B-QTL。研究表明,望水白的3B-QTL和6B-QTL抗扩展效应强且稳定,可以作为抗赤霉病基因资源在育种实践中充分利用。     

小麦抗条锈基因Yr52在品种改良中的应用

【目的】 评价小麦高温成株期（high temperature adult plant,HTAP）抗条锈病基因Yr52在生产中的应用价值,选育出农艺性状优良并高抗小麦条锈病品系,为充分利用现有高温成株期抗病资源、提高相关产量性状奠定基础。【方法】 通过回交和自交结合分子标记辅助选择育种方法,将小麦抗条锈病基因Yr52转育到轮选987（LX987）、百农矮抗58（AK58）和邯6172（H6172）中。在四川绵阳和陕西杨凌鉴定圃,用小麦条锈菌流行生理小种CYR32、CYR33和CYR34混合侵染,鉴定抗病基因载体品系和受体品种以及它们的高代家系的成株期抗病性。比对中国春参考基因组,结合Yr52两翼SSR分子标记Xcfa2040（6.8 cM-Yr52）和Xbarc182（1.2 cM-Yr52）,在目标基因物理区间内寻找35K SNP芯片标记,并开发成dCAPS和KASP分子标记,对BC₂F_5:6高代群体进行抗条锈病基因Yr52的检测。【结果】 抗病性鉴定和农艺性状评价表明,在19个具LX987背景的BC₂F_5:6家系中,抗条锈性表现为高抗（IT=0—3,DS=1%—20%）有11个,中抗（IT=4—6,DS=15%—30%）有8个,平均千粒重（TKW）、每穗穗粒数（KPS）、单株有效分蘖（PTN）、株高（PH）和穗长（SL）分别为45.33 g、46粒、7个、113.26 cm和10.05 cm。4个具AK58背景BC₂F_5:6家系全部表现高抗（IT=0—3,DS=5%—25%）;平均TKW、KPS、PTN、PH和SL分别为44.67 g、48粒、7个、96.54 cm和10.17 cm。5个具H6172背景的BC₂F_5:6家系全部表现高抗（IT=0—3,DS=5%—20%）;平均TKW、KPS、PTN、PH和SL分别为43.74 g、49粒、8个、109.72 cm和10.06 cm。分子标记检测结果表明,Yr52两翼连锁的分子标记Xbarc182、Xcfa2040和Xwmc557在后代群体中的检出率分别为78.57%、66.67%和66.67%,并成功开发出1个dCAPS标记Xdcaps-Yr52-1和1个KASP标记Xkasp-Yr52-1,两者在群体中的检出率分别为73.68%和41.67%。通过比较高抗（IT=0—3）与中抗（IT=4—6）水平家系的农艺性状,结果表明,IT在0—3的家系平均TKW（P>0.05）、PTN（P>0.05）和KPS（P<0.05）高于中抗水平的家系。结合各亲本抗病性和农艺性状筛选出PH为80—105 cm、PTN≥6个、KPS≥45粒、TKW≥42 g、SL≥8 cm的材料共5份。【结论】 Yr52仍对当前主要流行小种具有成株期抗性;将Yr52导入中国主栽感病小麦品种中,选育出综合抗病性和农艺性状良好的高代材料可用于培育多基因聚合的品种,丰富抗病基因的多样性,并实现持久利用。