【作者】 邓秀新； 邓占鳌； 章文才；

【Author】 Deng Xiuxin,Deng Zhanao & Zhang Wencai (Department of Horticulture Huazhong Agricultural University, Wuhan 430070)

【机构】 华中农业大学园艺系；

【摘要】 针对柑桔育种各过程中遇到的多胚性干扰、性器官败育、遗传上高度杂合等问题,本小组自八十年代初开始,从组织和细胸培养角度进行研究,取得如下进展:1)染色体变异普遗存在于柑桔茎段诱导的非胚性愈伤组织;2,4-D将促进变异的产生,而KT和NAA无此作用。从锦橙等品种的愈伤组织再生出同源四倍体、六倍体等变异。2)酶法分离柑桔胚囊,结果显示,脐橙胚囊为圆柱形、内空。3)花药培养再生出枳、宜昌橙杂种花粉植株,细胞学及同工酶分析证明再生植株为花粉起源。4)采用酶法分离柑桔(锦橙等品种)原生质体,经培养再生成完整植株,再生植株移栽成活率可达95％。目前,已有9个柑桔种和品种的原生质体再生植株。5)利用原生质体再生技术体系,进行耐盐突变体筛选,获得桃叶橙、锦橙耐NaCl 0．6％的小植株。6)培养技术的研究表明,采用低熔点琼脂糖包埋,可提高原生质体恢复频率,个别品种可达50％,一般品种达到30％,随后的悬浮培养可缩短原生质体成株时间。7)发现金柑属的一些种实生苗根部具有直接产生胚性愈伤组织的能力．如山金柑(Fortunella hindsii)种子播种后50天,16．5％实生苗下胚轴及根部具有这种能力。目前,通过胚珠诱导及实生苗直接产生的胚性愈伤组织有近20个种类,保存于本实验室中。8)采用PEG诱导配合方法,获得柑桔属与金柑属属间以及柑桔属内种间体细胞杂种7个,体细胞杂种生长旺盛。染色体数为四倍体,同工酶谱带为双亲的杂合。9)在起源上属杂种起源的柑桔种类,融合之后容易再生。几十个组合的融合试验表明,甜橙、柠檬、桔柚、柑类比较容易再生。10)柑桔体细胞杂种的花粉育性及抗寒性介于双亲之间,育性偏向高值亲本。粗柠檬与哈姆林甜橙种间体细胞杂种,花粉育性为74％。目前正在开展进一步的杂交,即以体细胞杂种为父本与柚子杂交培育三倍体。同时,将体细胞杂种作为砧木进行评价。11)体细胞与四分体小孢子原生质体之间的配合,即体配融合研究已再生出三倍体胚状体,并观察到花粉管生长现象。12)非对称融合研究的初步结果显示,不同品种的原生质体耐辐射和耐化学药剂处理的能力不同,处理后融合的原生质体已再生出多细胞团。更多还原

【Abstract】 Aiming at overcoming the problems of polyembryony, male/female abortion and genetic heterozygosi-ty in cirtus conventional breeding ,this group began the tissue and cell culture program at the beginning of 1980’s. The following progress have been achieved: 1)Chromosome number variation commonly existed in non-embryogenic calli of cirtus ; 2,4-D in the medium enhanced the variation, however, KT and NAA did not. Some tetraploid and hexaploid plants regenerated from the calli of the sweet orange cultivars such as "Jincheng" etc. 2)Embryo sacs of Navel orange was isolated by digesting the ovary with mixture of enzymes. The embryo sac of this cultivar was hollow inside and cylinder-shaped. 3)Anther culture of trifoliate orange, Ichang papeda hybrid resulted in the regeneration of plantlets. Cytological observation and isozyme analysis verified these plantlets were from the pollens. 4)Protoplasts isolated from "Jincheng" sweet orange and 8 other cultivars recovered cell division and regenerated into plants. The plants were transplated into soil with 95% survival rate. 5) Plantlets were recovered from the protoplasts of NaCl-tolerant callus lines of "Jincheng"and "Taoyecheng"sweet orange. 6)Embedding of the protoplasts with low-temperature melting agar solified medium increased the recovery of cell division to 50% for some cultivars and to 30% for general cultivars. 7)Em-bryogenic callus was induced directly from the hypocotyledon and roots of seedling of Hong Kong kumquat (Fortunela hindsii) in vitro. 50 days after the seeds were cultured in vitro, 16. 5% of the seedlings could derived the embryogenic callus. Until now,about 20 cultivars’or species’ embryogenic calli were obtained by this method and by culturing the nucellar tissue. 8) Two intergeneric and five interspecific somatic hybrid of citrus and citrus with its relatives were obtained by PEG-mediated cell fusion. The hybrid plants graw vigorously with 4 sets of chromosome and the combination isozyme bands of their parents. 9) Differences of regenerating capacity exist among genotypes. Those species or cultivars originated as hybrids,such as sweet orane,lemon, tangelo and mandarins were easier to regenerated after protoplast fusion. 10)The pollen fertility and cold hardiness of the somatic hybrids were intermediate between the parents and bias to the higher value parent. Somatic hybrid of rough lemon with "Hamlin" sweet orange has 74% of fertile pollens. The pollens have been pollinated onto pummelo to produce seedless triploid citrus plants. 11)Gametosomatic fusion of pummelo with sweet orange led to the regeneration of triploid embryos. Pollen-tube growth was observed during the culture. 12)A prelimary result of asymmetrical fusion showed that different cultivars had varied optimal dosage of X-ray irradiation and IOA. A few colonies have regenerated from the donor-recipient fusion.更多还原