NaCl胁迫对不同染色体倍性西瓜种子发芽特性的影响

用盐水浸种催芽方法,通过对蜜枚西瓜的二倍体、三倍体、四倍体在不同浓度NaCl胁迫下种子的发芽率、胚轴长度以及鲜重、发芽指数、活力指数等指标的测定,在30~90mmol/L低浓度下,倍性之间相对发芽率没有明显差异;在120 mmol/L以上浓度时,不同倍性之间差异明显,在150mmol/L NaCl胁迫下,其M4x、M3x、M2x相对发芽率分别为77.8%、63.4%、30.6%,180mmol/L时分别为37.8%、31.7%、0,在210mmol/L时,M4x和M3x仍然有种子萌发,耐盐性为M4x＞M3x＞M2x。     

流式细胞术(FCM)在贝类倍性检测中的应用

对某种生物来说,体内细胞核内所含的ＤＮＡ量总是一定的。利用流式细胞仪（ＦＣＭ）可在短时间内准确测出细胞中ＤＮＡ的含量,鉴别有机体的倍性。作者系统地介绍了用流式细胞仪检测鲍鱼、牡蛎、扇贝等经济贝类倍性的方法,包括机械法、化学法、抽取血液法及固定贝样的制备法等。另外,还报道了实验中新发现的一些现象,如牡蛎嵌合体及诱导过程中的非整倍体等。     

利用流式细胞术鉴定茉莉花基因组大小和染色体倍性

以收集的16份茉莉花资源及50份实生种质为材料,以玉米B73为内参,采用流式细胞术估测茉莉花基因组大小,并以二倍体品种为对照,计算茉莉花染色体倍性。结果表明:内参与待测样品峰值能完全分开,无重叠峰,峰型清晰集中,可对茉莉花基因组大小进行有效估测;供试材料中有56份二倍体,基因组大小为0.54～0.63 Gb,有7份三倍体,基因组大小为0.79～0.96 Gb,有3份四倍体,基因组大小为1.04～1.12 Gb;从收集的资源中鉴定出二倍体和三倍体,未见四倍体,而从实生种质中鉴定出3个四倍体、2个三倍体,表明实生选种是茉莉花种质创新的一条有效途径;在已明确花冠类型的材料中,三倍体及四倍体均为单瓣型茉莉。该研究结果为茉莉花倍性育种及实生选种提供科学依据。     

利用流式细胞术鉴定桦木染色体倍性和DNA含量

基于流式细胞术（FCM）研究体系,构建能快速、准确鉴定桦木属植物倍性和测定DNA含量的研究体系,是测定不同桦木属植物倍性与基因组大小的有效方法。使用流式细胞术检测7种桦树属类物种,以物种不同生长状态（嫩叶、幼叶、成熟叶）为实验材料,不同存储方式（常温、冷藏和聚乙烯吡咯烷酮保存PVP）进行实验处理,对9种常用的裂解液进行筛选与优化。结果表明：桦木属植物DNA含量测定中,新鲜幼叶以1% PVP浸泡常温保存,并使用MgSO₄裂解液制备细胞核悬浮液上机效果最佳;桦木属植物中,基因组倍性依次为黑桦（(2.09 ± 0.04) Gb,8倍体） > 坚桦（(1.53 ± 0.08) Gb,6倍体） > 光皮桦（(0.87 ± 0.05) Gb,4倍体）=岳桦（(0.80 ± 0.07) Gb,4倍体） > 垂枝桦（(0.46 ± 0.03) Gb,2倍体）=河桦（(0.51 ± 0.01) Gb,2倍体）。因此,桦木属植物DNA倍性和DNA含量可以通过FCM研究体系进行测定,且3倍体（(0.66 ± 0.02) Gb）子代的鉴定结果表明光皮桦与河桦之间不存在生殖隔离。     

流式细胞术在水生生物DNA含量和倍性分析中的应用

利用流式细胞仪对鲤鱼、银鲫、黄颡、牙鲆等淡水和海水鱼类进行了DNA含量测定或倍性分析。通过几百个样品的测定和分析,认为流式细胞仪在DNA相对含量测定和倍性分析上结果比较稳定一致,可以用于大量样品的测定分析。同时对待测样品的保存、处理及上样量等进行了一系列比较研究,找出最好的保存方法、最简便的样品处理方法和最少的上样量。流式细胞仪在水生生物的遗传育种、种群分化等方面有很重要的应用价值。     

不同倍性苹果叶片不定植株再生研究

以苹果二倍体、三倍体、四倍体共２８个品种的无菌苗叶片为试材,研究了倍性、光和暗培养及叶片的生长部位对叶片不定梢再生的影响。结果表明：多倍体比二倍体容易再生不定梢,平均不定梢再生率,三倍体达９８．４％,二倍体６８．４％,一个四倍体品种达９３．３％。暗培养比光培养有利于促进不定梢再生,无菌苗顶部刚展开的嫩叶比中下部成熟老化叶再生率高。     

大白菜—甘蓝异附加系的获得与鉴定

 异附加系是利用外源基因进行品种改良和基因组研究的重要材料。以大白菜—甘蓝异源三倍体（AAC）与二倍体大白菜（AA）回交一代为材料,经过细胞学鉴定,从中筛选出大白菜—甘蓝7号单体附加系CO-7-1和9号单体附加系CO-9-2。CO-7-1、CO-9-2自交后代中外源染色体出现频率分别为35.3%、20.0%。从CO-7-1的自交后代中分离鉴定出二体异附加系CO-7-1D的比率为11.8%。该异附加系的获得为分析大白菜和甘蓝的亲缘关系,进一步获得大白菜和结球甘蓝易位系、代换系提供了基础材料。     

应用LSCM和SEM鉴定银杏花粉的倍性

以经秋水仙碱诱导获得的银杏大花粉为材料,以未经处理的正常银杏花粉为对照,利用扫描电子显微镜和激光扫描共聚焦显微镜分别观察2种花粉表面形态,并分析对比其细胞内的DNA相对荧光量与银杏大花粉核内染色体倍性关系,为正确检出银杏二倍体花粉奠定重要工作基础。研究结果表明,此方法用于花粉粒的倍性鉴定科学准确,所需试验样本少,实用性强,在植物花粉倍性鉴定中有着较好的应用前景。      

辣椒花药培养再生植株染色体倍数检测研究

采用流式细胞仪(FCM)对7个甜椒F1和3个辣椒F1的花药培养的再生株,在幼苗期进行了倍性鉴定.流式细胞仪的矩形图中清楚显示出每份材料叶片的DNA含量,即检测出单倍体、二倍体、三倍体或单倍体加二倍体的混倍体.研究表明:辣椒花药培养再生株中,单倍体和二倍体比率约为70.91%、25.45%.流式细胞仪可以快速且准确的检测出试材的染色体倍性,与座果结子的鉴别结果相一致.本文还讨论了采用流式细胞仪的优势以及存在的问题.     

Comparisons of age,growth, and maturity between male and female,and diploid and triploid individuals in Carassius auratus from Okinawa‐jima Island,Japan

• 1. Carassius auratus, a primary freshwater fish with bisexual diploid and unisexual gynogenetic triploid lineages, is distributed widely in and around the Eurasian continent and is especially common in East Asia. East Asian C. auratus diverged genetically to form local endemic populations in different regions, and those distributed in the Ryukyu Archipelago form a local endemic population that can be regarded as an evolutionarily significant unit because of its high phylogenetic independence and evolutionary distinctiveness. Although the evolutionary uniqueness of this population should be conserved, its distribution area and population size are decreasing rapidly, and some island populations are currently considered endangered or already extinct.
• 2. To develop effective conservation measures to stop the current decline of Ryukyuan C. auratus, ecological data need to be collected. In this study, life history data for a C. auratus population distributed in the Hiji River system were collected by estimating age, growth, and spawning season.
• 3. The spawning season of C. auratus in the Hiji River extended from March to September, peaking during March–May. Females became sexually mature in their second year, but males reached maturity and were able to spawn as early as in the late spawning season of their year of hatching. Once having reached sexual maturity, males probably continuously stay ripe throughout their life.
• 4. Sagittal otoliths of C. auratus proved to be useful ageing structures because one annual increment is formed on the sagittal otolith before the spawning season in each year. The oldest fish observed were a 10‐year‐old female and an 11‐year‐old male. Females showed faster somatic growth and higher final standard length than males, and a sexual size dimorphism was observed.
• 5. The standard length at each age class did not differ between diploid and triploid C. auratus, suggesting that triploid growth rates were almost equal to those of diploids. Copyright © 2009 John Wiley & Sons, Ltd.