百合品种染色体倍性观察

 利用染色体常规制片技术分析了45个从荷兰引进的百合品种的染色体倍性,包括21个亚洲百合、3个麝香百合、7个东方百合、8个LA杂交品种、2个LO杂交品种、4个OT杂交品种。在21个亚洲百合中,12个品种（‘Eleganza’、‘Monte Negro’、‘Renoir’、‘Black Bird’、‘Butter Pixie’、‘Orange Matrix’、‘Petit Brigitte’、‘Pink Pixie’、‘Lollypop’、‘Red Latin’、‘Marrakech’和‘Pollyanna’）为二倍体（2n = 2x = 24）,5个品种（‘Navona’、‘Orange Pixie’、‘Elodie’、‘Vermeer’和‘Lyon’）为三倍体（2n = 3x = 36）,4个品种（‘Brunello’、‘Tresor’、‘Val di Sole’和‘Detroit’）为四倍体（2n = 4x = 48）;3个麝香百合品种（‘White Heaven’、‘Gelria’和‘White Fox’）为二倍体（2n = 2x = 24）;7个东方百合品种（‘Siberia’、‘Sorbonne’、‘Maru’、‘Dynamite’、‘Dordogne’、‘Montezuma’和‘Miss Lucy’）为二倍体（2n = 2x = 24）;8个LA杂交品种（‘Brindis’、‘Courier’、‘Pavia’、‘Advantage’、‘Mestre’、‘Mombasa’、‘Pirandello’和‘Serrada’）为三倍体（2n = 3x = 36）;两个LO杂交品种（‘Triumphator’和‘White Triumph’）为三倍体（2n = 3x = 36）;4个OT杂交品种中‘Yelloween’和‘Red Dutch’为二倍体（2n = 2x = 24）,‘Conca D’Or’和‘Golden City’为三倍体（2n = 3x = 36）。该结果表明,组内杂交品种（亚洲百合、东方百合和麝香百合）中,除亚洲百合中有5个三倍体和4个四倍体品种外,其余22个为二倍体品种,因而多数组内杂交品种为二倍体品种;而组间杂交品种（LA、OT和LO）,只有OT中2个品种为二倍体,其余12个皆为三倍体。     

秋水仙素离体诱导冬枣和酸枣四倍体

 以冬枣和酸枣组培苗丛芽为材料, 研究了秋水仙素诱导染色体倍性变异的最佳浓度与时间组合、多倍体的特征及其纯化技术。结果表明: 秋水仙素处理的最佳组合为50 mg·L ^{- 1}秋水仙素处理40 d,诱导酸枣和冬枣染色体加倍的频率分别达36.37%和26.67%。嵌合体经3～4次继代分离得到了纯化, 并对纯化后的变异株进行了增殖和生根。变异株根尖染色体数加倍(2n = 4x = 48) , 叶片增厚, 栅栏组织、海绵组织明显发达, 茎尖LⅠ、LⅡ和LⅢ层细胞均显著变大, 充分表明获得的变异株为同质四倍体。同质四倍体的主要特征为: 叶片增大, 叶色浓绿, 叶缘锯齿增大, 保卫细胞增大, 气孔密度降低。变异株在诱导期间表现出生长缓慢、叶片变圆、节间变短的暂时现象。     

不同倍性蝴蝶兰杂交后代的染色体倍性研究

 对不同倍性蝴蝶兰小孢子母细胞减数分裂及其杂交后代的根尖染色体数进行了检测。结果表 明,除三倍体和三倍体杂交未能产生杂交后代外,不同倍性蝴蝶兰杂交后代的倍性均出现分离。二倍体和 二倍体、二倍体和四倍体杂交均产生二倍体、三倍体和四倍体;二倍体和三倍体杂交产生二倍体、三倍体、 五倍体和非整倍体;三倍体和四倍体随正反交不同而异,三倍体@四倍体的后代倍性有三倍体、四倍体、 八倍体和非整倍体,而四倍体@三倍体的后代倍性有三倍体、四倍体、五倍体和非整倍体;四倍体和四倍 体杂交产生二倍体、三倍体、四倍体、五倍体、六倍体和非整倍体。不同倍性蝴蝶兰的小孢子母细胞减数 分裂普遍存在微核、落后染色体和三分体等异常现象,导致小孢子和杂种后代的倍性出现多样性。     

以异源四倍体体细胞杂种为父本与二倍体杂交创造柑橘三倍体的研究

 2001～2002连续两年, 以沙田柚、本地早橘、中秋橘、HB柚、国庆4号温州蜜柑等二倍体品种为母本, 以NS (橘柚+无酸甜橙) 、NH (橘柚+ HB柚) 、SH (无酸甜橙+ HB柚) 、VM (伏令夏橙+橘橙) 、HD (甜橙+丹西橘) 等优良四倍体体细胞杂种的花粉授粉, 通过胚挽救技术获得再生植株。经细胞流式仪和染色体计数观察表明, 两年从10个授粉组合中共获得244株三倍体和10株四倍体。在这些三倍体中有147株来自沙田柚为母本的组合。目前已有172株三倍体和4株四倍体植株移栽成活。这些材料为进一步选育无核三倍体品种奠定了基础。     

西瓜新品种‘蜜枚四培体’的选育研究

‘蜜枚四倍体’是1975年用秋水仙精诱导二倍体西瓜,1980年选育成的.经过组合选配试验、品种比较试验、病菌孢子接种试验及生产栽培,确认是一个配合力强的优良四倍体西瓜品种.该品种可直接应用于生产,但更多地是用作杂交育种、用作四倍体杂交一代品种和三倍体无籽西瓜品种的亲本.用它作母本已选育出‘蜜枚无籽一号’等三倍体西瓜新品种,并大面积生产载培.     

不同枣品种抗寒性的比较

采用电导法,在萌芽前后对‘冬枣’、‘金丝小枣’、‘泗洪大枣’、‘木枣’、‘龙爪枣’和‘临沂梨枣’6个枣树品种的枝条进行抗寒性研究,以了解不同枣树品种的抗寒性,寻找优良的抗寒资源。结果表明:6个枣树品种萌芽前后的的抗寒性表现差异较大,萌芽前的抗寒性强弱顺序为:‘泗洪大枣’‘木枣’‘临沂梨枣’‘金丝小枣’≈‘龙爪枣’‘冬枣’,萌芽后的抗寒性强弱顺序为:‘冬枣’‘龙爪枣’≈‘临沂梨枣’‘金丝小枣’≈‘泗洪大枣’≈‘木枣’。     

不同倍性西瓜花粉形态观察

 采用扫描电子显微镜对不同倍性西瓜12个品种的花粉形态进行了系统观察，结果表明：二倍体花粉多为近长球形，极轴/赤道轴(P/E)值为1.283，具3孔沟，花粉整齐一致；四倍体花粉为圆球形,P/E值为1.111，有3孔沟，4孔沟，多孔沟，其中有异形花粉、粘连花粉和空瘪花粉等；三倍体花粉全部为空瘪花粉。从孢粉学角度阐述了四倍体花粉萌发率低，三倍体花粉不育的原因。     

不同倍性西瓜幼苗叶片超微结构的比较

以蜜枚西瓜二倍体、三倍体、四倍体作为实验材料,通过透射电镜观察不同倍性的西瓜幼苗叶片超微结构的差异,结果表明,与二倍体相比,三倍体和四倍体西瓜的叶片内,维管束组织较强,细胞较大,单个细胞内的叶绿体、线粒体、基粒以及基粒片层数增加,细胞活性增强,表现出基因的剂量效应和多倍体的抗性优势。     

亚洲百合杂交新品种‘雨荷’

 ‘雨荷’是以二倍体亚洲百合‘金角’（Golden Horn）为母本,四倍体亚洲百合‘布鲁内罗’（Brunello）为父本,杂交选育而成的三倍体新品种。花橙红色,有少量紫褐色斑点,花瓣肥厚。花丝和花柱橙色,花粉黑褐色。株高75 ~ 80 cm,花径14 ~ 15 cm。生长强健,抗逆性强,适宜中国华东地区栽培。     

以柑橘多胚性二倍体母本倍性杂交培育三倍体

2009-2012年,以柑橘8个多胚性二倍体品种为母本与近年始花的5个异源四倍体体细胞杂种和1个同源四倍体分别杂交,培育三倍体新种质。连续4年共配置15个杂交组合,授粉4 442朵花,坐果1 484个,平均坐果率33.4%;用于幼胚挽救的果实1 075个,共培养幼嫩种子12 578颗,经生芽、生根诱导获得再生植株2 832个;以流式细胞仪对所有再生植株倍性检测,15个组合共获得三倍体401个,四倍体121个;移栽成活三倍体349个,四倍体98个。对W. 默科特 × NH组合89个株系的三倍体的SSR分子鉴定表明,所有三倍体后代均为双亲的有性杂种。     

用AFLP分子标记鉴定冬枣自然授粉实生后代杂种的研究

 应用AFLP技术对65株冬枣自然授粉实生后代进行杂种鉴定, 从81对EcoRⅠ和MseⅠ选择性引物中筛选出12对带型清晰且多态性较高的引物。用这12对引物共扩增出517条谱带, 其中多态性带376条, 多态性百分率为72.7%。共扩增出金丝小枣特征带10条, 鉴定出34株冬枣×金丝小枣杂交实生苗;扩增出尖枣特征带7条, 鉴定出冬枣×尖枣杂交实生苗15株; 不能确定的有16株。     

Induction of viable 2n pollen in sterile Oriental × Trumpet Lilium hybrids

In order to induce viable 2n pollen from highly sterile diploid Oriental × Trumpet (OT) (Lilium), N₂O was used to treat flower buds of four sterile diploid OT cultivars (‘Nymph’, ‘Gluhwein’, ‘Yelloween’, and ‘Shocking’) at different stages of meiosis. There was no pollen germination in the controls. However, after N₂O treatment at 600 kPa, three of the OT hybrids (‘Nymph’, ‘Gluhwein’, and ‘Yelloween’) not only exhibited fertile flower percentages (4.3–16%), but also higher rates of pollen germination (18.8–72.5%). In addition, both the fertile flower percentages and rates of pollen germination were higher following 48 h N₂O treatment at 600 kPa than the 24 h treatment. Following 72 h N₂O treatment at 600 kPa, most flower buds or plants were damaged and any undamaged flowers showed abnormal anthers at the time of flowering. This indicated that 48 h of N₂O treatment at 600 kPa was optimal to induce viable 2n pollen in three out of four sterile hybrid OT lily cultivars. These results also showed that prophase I – metaphase I was the optimum stage of meiosis at which to induce 2n pollen by N₂O treatment in lily hybrids.     

Fruit set,seed development and embryo germination in interploid crosses of citrus

Interploid crosses of diploid Kinnow mandarin, Succari sweet orange and Sweet lime with tetraploid Kinnow were made reciprocally for the production of triploid plants. Low fruit set and occurrence of underdeveloped or empty seeds was common in all interploid crosses. The hybrid fruits harvested after 12–14 weeks or 7 months after pollination produced many underdeveloped and few developed seeds; however, tetraploid Kinnow as seed parent yielded more developed seeds per fruit. The under developed seeds were devoid of endosperm. Nucellar embryony was higher in the diploid than in the tetraploid strain of Kinnow. Immature embryos of seeds harvested 12–14 weeks after pollination were cultured in vitro on MS media supplemented with adenine sulphate (20 mg l⁻¹) and malt extract (500 mg l⁻¹). Maximum germination (75%) of hybrid embryos from underdeveloped seeds was obtained in 4× × 2× cross of Kinnow strains. The germinated plantlets were transferred into pots and noted 59–89.3% survival rate in various crosses.     

Creating triploid germplasm via induced 2n pollen in Capsicum annuum L.

Summary

2n pollen of diploid chili (Capsicum annuum L. ‘Xianjiao’) was induced by heat shock (35.5?C, 4.h) or low temperature treatment (118C, 48.h). The percentages of 2n pollen were increased to 8.3% and 10.5% respectively. The cytogenetic mechanisms of 2n pollen formation were first division restitution, second division restitution and abnormal cytokinesis. Diploid 2n pollen was less competent than n pollen in fertilization. Only one triploid plant arose from 78 progenies after fertilization by 2n pollen. The four offspring plants of the triploid were diploid. The morphological characters of the triploid and microsporogenesis were also evaluated.     

Tetraploid muskmelon alters morphological characteristics and improves fruit quality

Tetraploid muskmelon plants were induced successfully from diploid Cucumis melo inbred M01-3 (2n = 24) by colchicine. The morphological characteristics and fruit qualities of diploid and tetraploid muskmelons were investigated. The results showed that the leaves and flowers of the tetraploid plants were markedly larger, the plants were obviously higher, and the stems were thicker than those of the diploid plants. Transmission electron microscope observation revealed that the numbers of chloroplast, granule and grana, and the length of chloroplast and granule of the tetraploid plant leaves were significantly more or longer than those of the diploid plants. The soluble solid, soluble sugar and vitamin C contents in the tetraploid fruit were distinctly higher than those in the diploid fruit. The weight of the tetraploid fruit was 30% heavier than that of the diploid fruit. And the seeds from the tetraploid plants were broader and thicker than those from the diploid plants. Together, our results suggest that the tetraploid muskmelon exhibited better agronomical characteristics than the diploid muskmelon and the tetraploid muskmelon could be used as the improved variety and a potential germplasm for the development of triploid fruit.     

枣树免去雄杂交育种的设计与实践

在枣树杂交育种中,因其花朵很小去雄难、坐果率低、胚败育严重,常规人工授粉杂种得率通常只有万分之一左右,致使杂交育种长期徘徊不前,至今未有人工杂交枣新品种问世。作者历时10余年,以解决去雄难和胚败育严重两大瓶颈问题为突破口,在系统研究枣树不同种质结实特性和花粉育性并攻克幼胚挽救技术的基础上,探索建立枣树免去雄杂交育种的高效技术体系,并在育种实践中加以改进和完善。通过人工控制杂交,成功获得了2 个组合的211 个杂种后代。从育种目标、亲本选配、免去雄控制杂交、授粉方法、胚培养及杂种的分子标记鉴定等方面提出了枣树杂交育种的设计方案与实现途径。并对今后枣树杂交育种的攻关重点和发展前景进行了分析讨论。     

天然四倍体枇杷‘B431’减数分裂观察及育性分析

通过流式细胞术和染色体制片确定枇杷天然实生筛选株系‘B431’为四倍体。采用改良涂片法观察了其花粉母细胞减数分裂过程,离体萌发法和人工杂交分析其育性,染色体计数法检测了其后代的染色体数。结果表明:天然四倍体枇杷‘B431’减数分裂过程中染色体存在异常行为;染色体配对以二价体为主,也可见少量单价体和部分多价体;减数分裂进程中出现板外染色体、早熟染色体、落后染色体、染色体桥、微核和极少的三极体等异常现象;四分体时期有二分体、三分体、多分体和微核等异常现象。四倍体枇杷‘B431’育性低于二倍体,但其花粉活力达到66.29%±2.22%,杂交结实率与二倍体差异不显著,仍有较高的育性,其与二倍体的杂交后代三倍体率达到66.67%,可以作为三倍体创制的核心亲本。     

Control of black spot disease caused by Alternaria alternata on jujube (Ziziphus jujuba Mill. cv. Dongzao) using HarpinXoo protein

Summary

Currently, no adequate control measures exist for the fungal disease, black spot (Alternaria alternata (Fr.) Keissler) on ‘Dongzao’ jujube (Ziziphus jujuba Mill. cv. Dongzao). Black spot is an important factor limiting jujube fruit yield under certain conditions. In this study, three concentrations (10, 20, or 30 µg ml^–1) of the Harpin_Xoo protein, or water (negative control), were sprayed onto ‘Dongzao’ jujube trees to control black spot disease. Following Harpin_Xoo protein treatment, its effects on the control of black spot disease were determined, and the levels of a defence-related substance [i.e., salicylic acid (SA)], and the activities of peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia lyase (PAL) were measured. The incidence of black spot disease was significantly decreased, compared with water-treated control, fruit by ≤ 88.4%. After 2 d, SA levels, and POD, PPO, and PAL activities in Harpin_Xoo-treated fruit were clearly higher than those in control fruit. After fruit had been stored for 45 d at 0ºC, SA levels, and POD and PPO activities showed no differences between the Harpin_Xoo treatments and the controls, but PAL activities in Harpin_Xoo-treated fruit were lower than those in the controls. The most appropriate concentration of Harpin_Xoo protein to control black spot disease was 20 µg a.i. ml^–1. These results suggest that the Harpin_Xoo protein induced systemic acquired resistance in ‘Dongzao’ jujube trees and may offer a worthwhile strategy for disease control.     

利用胚挽救技术创制葡萄多倍体种质的研究

为培育三倍体无核葡萄新品种,以二倍体欧洲葡萄无核品种红宝石无核、爱莫无核、黎明无核和欧山杂种北醇及四倍体欧美杂种藤稔、黑奥林为亲本,进行了红宝石无核×藤稔、黎明无核×藤稔、爱莫无核×黑奥林、藤稔×北醇、黑奥林×北醇5个组合的杂交,通过胚挽救技术获得杂种幼苗41株。在此基础上,利用流式细胞术、染色体计数的方法对所获得的杂种幼苗进行了早期倍性鉴定,结果表明有10株杂种为三倍体,6株为四倍体,4株为非整倍体,其余21株为二倍体。这将为进一步选育出三倍体无核葡萄新品种和提供新的育种材料奠定基础。     

四倍体鲜食枣新品种‘辰光’

‘辰光'是‘临猗梨枣'经秋水仙素诱变获得的四倍体枣新品种。果实极大,近圆形,平均单果质量39.6g,可食率为98.5%;果皮薄,果肉质地细腻酥脆,汁液多,味甜,口感极佳;早果,速丰,是品质优良的中熟鲜食枣品种;在河北省中南部地区表现良好。