二倍体马铃薯资源现状及应用研究进展

二倍体马铃薯(2n=2x=24)中存在大量优良抗性及品质性状基因,发掘和利用这些优良基因对于提高马铃薯的产量和质量具有重要作用。二倍体马铃薯基因组简单,易于进行遗传分析,因而被广泛应用。本文在前人研究的基础上,对近年来二倍体马铃薯种质资源的现状及其在染色体工程育种、细胞工程育种、分子标记辅助选择和功能基因组分析等方面的应用进行了概述。     

草石蚕四倍体与二倍体的品质分析

[目的]分析草石蚕四倍体与二倍体的品质。[方法]对引进的草石蚕二倍体材料进行秋水仙素诱导处理,成功获得草石蚕的四倍体材料,然后将草石蚕二倍体和四倍体材料进行栽培试验,并分析草石蚕的干物质含量、可溶性蛋白质含量和可溶性糖含量3个重要品质指标。[结果]四倍体叶片中干物质含量、可溶性蛋白质含量和可溶性糖含量比二倍体分别增加了43.16%、9.46%和21.74%;而四倍体块茎中干物质含量、可溶性蛋白质含量和可溶性糖含量比二倍体分别增加了13.12%、21.89%和7.47%。[结论]四倍体的营养成分要比二倍体高,在经济价值上比二倍体更优越。     

Extended genetic resources of Dactylis glomerata subsp. izcoi in Galicia (northwest Spain)

Dactylis glomerata subsp. izcoi, endemic to Galicia (NW Spain), includes diploid and tetraploid cytotypes. The present paper results from ongoing research on the distribution of Dactylis in Galicia. Tetraploids dominate all kind of habitats, but diploids do occur in restricted areas. After intensive exploration carried out by the Misión Biológica de Galicia, dealing with diploid populations of subspecies izcoi, 13 new diploid localities were recently detected along the ridge called Macizo Galaico Duriense three on the west side of the ridge and the remainder on the east, persisting in ancient habitats in the following communities: Quercetea robori-petrea, Erico-Ulicetalia, Ericion australis and Ulicion nanae. Two diploid populations have been detected for the first time in Coruña Province. However, no diploids were found on the west side (near the coast) of Coruña and Pontevedra Provinces, probably due to Atlantic influence.     

网纹甜瓜单倍体植株生产及倍数性鉴定

以软X－射线（总辐射剂量650Gy)照射过Cucumis melo var.momordica植株上的雄花花粉与网纹甜瓜杂种一代‘Rubia-Red’（Cucumis melo var.reticulatus Naud.)已于上一日去雄的雌花授粉，经‘雌核发育’诱导形成单倍体胚。3周后从采收的4个幼果中获得种子1967粒，种子经灭菌后接种于1／2MS＋蔗糖30g/L gellan gum 3g/L固体培养基上，3周后将萌发的12个幼胚移植到MS＋葡萄糖20g/L gellan gum 3g/L培养基上培养。由假授精胚珠诱导成的4株幼苗经倍数性分析仪（PA型，德国Partec公司制造）鉴定为单倍体植株。幼胚和单倍体植株的诱导率为0．6％和0．2％。通过茎节切段进行增殖培养，10周后获得54株生根再生植株。     

Studies on sperm of diploid and triploid tench, Tinca tinca (L.)

The tench Tinca tinca is an interesting fish from the viewpoint of polyploidy and related atypical reproduction aspects. Triploid tench were produced artificially. Studies of spermiation as well as of sperm motility and structure were performed on several triploid and diploid males simultaneously with individual experimental crosses with diploid females to define their reproductive capacities. The testes of triploids visually looked less developed in the most of cases with lower sperm production (0.05 cm³ sperm per male), GSI and weight of testes compared to diploids (0.58 cm³ sperm per male). Analysis of variance showed significant influence of ploidy level on the percentage of motile spermatozoa. Triploidy did not change percentage of live spermatozoa and velocity of spermatozoa at the first time of sperm movement. The study of sperm structure by scanning electron microscopy revealed that most sperm cells were of normal structure with some anomalies. Sperm heads of triploid and diploid males were mostly round-shaped, 1.86±0.2 and 1.6±0.18 μm in diameter. The midpiece of triploid spermatozoa was slightly narrower than that of diploid ones with typical cylindrical shape. Flow cytometry revealed sperm cells of triploids to be largely aneuploid (1.47 n) with high mosaic DNA, oscillating from haploid DNA content (1.0 n) to diploid DNA content (1.9 n). Experimental crosses between triploid males and diploid females revealed that these males were capable to stimulate effective development with relatively high level of fertilization and hatching rates from 0 to 70%. In conclusion, triploidization does not seem to guarantee sterility of tench.     

草莓属植物染色体核型分析

[目的]分析二倍体野生种草莓的核型,为探讨草莓的起源、进化及遗传育种研究提供依据。[方法]对草莓属（Fragaria）植物4个二倍体种森林草莓（F.vesca L.）、纤细草莓（F.gracilis A.Los.）、黄毛草莓（F.nilgerrensis Schidl）和五叶草莓（F.pentaphylla A.Los.）进行了核型分析。[结果]纤细草莓的核型为2n=2x=14=10m＋2sm＋2m＊,属1B类型;黄毛草莓为2n=2x=14=14m,属1A类型;五叶草莓为2n=2x=14=12m＋2sm,属1A类型;森林草莓为2n=2x=14=14m,属1A类型。[结论]草莓二倍体及品种核型对称性为：黄毛草莓〉森林草莓〉五叶草莓〉纤细草莓,供试草莓种的亲缘进化顺序可能为黄毛草莓、森林草莓、五叶草莓、纤细草莓。     

四倍体与二倍体白桦的光合特性比较

以4年生四倍体白桦和二倍体白桦为试材,对其光合作用日变化、光响应曲线、CO2响应曲线和叶绿素荧光参数进行测定.结果表明:①四倍体和二倍体白桦均有光合作用"午休"现象,四倍体的全天最大净光合速率极显著高于二倍体(P＜0.01),较二倍体提高了24.81%.②光饱和点、光补偿点和羧化效率等指标在两者之间的差异也极显著(P＜...     

同源四倍体水稻若干性状的初步研究

通过对同源四倍体630(4)和其相应二倍体研究表明:同源四倍体630(4)种子的长、宽和千粒重显著或极显著高于相应的二倍体.同源四倍体630(4)饱满的种子仅占31.14%,极显著低于相应的二倍体.同源四倍体630(4)种子的发芽率也显著低于相应的二倍体.四倍体的剑叶长、剑叶宽显著高于相应的二倍体.但分蘖能力却降低.同源四倍体630(4)的株高显著高于630(2).四倍体水稻表皮气孔的长、宽均极显著的高于相应的二倍体.而叶绿素含量却相反,四倍体水稻叶片叶绿素含量均低于相应的二倍体.     

二倍体鸭茅染色体加倍的研究

研究了秋水仙碱不同浓度(0.05%、0.2%、0.3%)、不同处理时间(1d、2d、3d)、种子不同萌芽阶段(芽长<0.5cm、1~2cm、>3cm)对二倍体鸭茅染色体加倍效果及生长发育的影响。结果表明,三个因素对诱变效果均有一定程度的影响,所有染色体加倍植株均为混倍体,即同一根尖细胞中二倍体和四倍体细胞共存;混倍体早期生长弱于二倍体,以后的生长发育及开花期形态特征二者几乎无差异。     

二倍体泥鳅与大鳞副泥鳅及杂交F1精子结构与活力

二倍体泥鳅与大鳞副泥鳅杂交能够顺利获得杂交后代,其正反交核型都为（2n=49）,但杂交后代精巢表现出明显的发育迟缓现象,杂交泥鳅自交与回交实验表明,其雄性不可育。为了解二倍体泥鳅和大鳞副泥鳅杂交F₁雄性不育的原因,实验通过计算机辅助精子活力分析系统（CASA）、光学显微镜、扫描电镜、透射电镜、流式细胞技术分别对二倍体泥鳅（DD）、大鳞副泥鳅（PP）、其正反杂交F₁（DP）和（PD） 4种泥鳅精子的形态结构与活力进行了分析。结果显示,激活30 s时,DD和PP的精子运动率分别为76.50%±0.70%和75.17%±8.60%,极显著高于DP （3.65%±1.75%）和PD （2.68%±0.63%）,且杂交泥鳅的精子的平均运动速度（VAP）、平均曲线速度（VCL）、平均直线运动速度（VSL）等运动参数也极显著低于DD和PP,说明杂交泥鳅精子的活力极其低下。应用流式细胞技术对4种泥鳅精巢内细胞进行倍性鉴定,发现DD和PP精巢内大多为1N精子,而DP和PD精巢内除了正常单倍体精子外,还有大量的2N和4N以及少量的8N细胞。通过扫描电镜和透射电镜...