【作者】 潘光堂；

【导师】 荣廷昭；

【作者基本信息】 四川农业大学 ， 作物遗传育种学， 2004， 博士

【摘要】 针对我国、特别是西南山地所需玉米转基因工程育种优良受体极为匮乏和反应玉米幼胚培养能力的2个主要性状，即玉米幼胚胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数的遗传变异规律十分不清楚的实际情况，本研究从筛选玉米转基因工程所需要的优良受体入手，采用单因素遗传交配设计、双列杂交遗传交配设计、世代基因效应等传统数量性状分析方法，以及现代分子标记定位主效QTL分析方法，对玉米幼胚胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数等2个性状进行了较为系统的分析研究，取得以下主要研究结果： (1) 于2000年和2001年通过对我国、特别是西南地区近50份优良自交系和近30个杂交组合，在相同培养条件下，对幼胚培养胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数等2个幼胚培养能力性状进行了筛选与鉴定，发现玉米不同基因型具有完全不同的幼胚培养胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数，但幼胚培养胚性愈伤组织诱导率与胚性愈伤组织绿苗发生数并不具有必然的相关关系，有的基因型，如自交系18-599(白)和18-599(红)在胚性愈伤组织诱导率和愈伤组织绿苗发生数等2个性状都表现相当优异；有的基因型，如自交系综31，仅幼胚培养胚性愈伤组织诱导率性状表现高于19-599(白)和18-599(红)，但在胚性愈伤组织绿苗发生数这一性状则与它们有相当大的差距，仅为19-599(白)和18-599(红)的1／3左右；有的基因型，如S37、R08、R15、P138、A318等玉米自交系不仅幼胚培养胚性愈伤组织诱导率很低，平均仅在3％左右，而且胚性愈伤组织绿苗发生数表现也很差，基本上没有分化成苗。总体而言，在表征幼胚培养能力的2个性状上，杂交种优于自交系。 (2) 选用在配合力、抗病性、农艺性状等玉米杂交育种性状与幼胚培养胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数等转基因工程育种性状都表现相对十分优异的18-599(白)、18-599(红)和综31等3个自交系，以及杂交育种性状表现优良、但转基因工程育种性状表现极差的A318、P138和R15等3个自交系为亲本，按照Griffing方法1组配双列杂交，进行Griffing的配合力分析。Griffing的双列杂交配合力分析效应与方差分析表明，对胚性愈伤诱导率和胚性愈伤组织绿苗再生数等2个性状而言，亲本间的GCA效应和组合问的SCA效应差异都达极显著水平；自交系18-599(红)和18-599(白)在所研究2个性状上不仅GCA效应高，而且它们各自所配组合的SCA效应的方差也较小，表明这2个自交系该性状传递力强且传递整齐，以它们作为亲本容易获得在胚性愈伤组织诱导率和胚性愈伤组织绿苗再生数等2个性状表现上高而稳定的后代组合；自交系综31在胚性愈伤组织诱导率性状上的GCA效应最大，在胚性愈伤组织绿苗再生数性状的GcA效应居第3，然而所配组合的s以效应之方差也较大，表明该自交系该性状虽传递能力强但传递不够整齐，即杂交后代表现不稳定;而自交系A318、R15和P138则表现出显著负向G以效应.综合来看，在本研究所涉及的玉米自交系中，对玉米幼胚培养能力性状，自交系18一599(白)和18一599(红)的利用潜力及价值最大. (3)对按Griffing方法1组配的双列遗传交配设计，采用Hayman的双列杂交遗传分析探测研究性状的遗传模型，结果发现，两种检测方法都一致表明幼胚培养胚性愈伤组织诱导率性状的遗传呈加性一显性模型遗传，显性效应表现为部分显性到完全显性，且显性基因大都表现为减效;而胚性愈伤组织绿苗发生数性状，两种检测方法所得结果不一致，该性状的遗传可能存在连锁或其它更复杂的情况，也可能是由于组配双列杂交设计的亲本较少，或是该度测该性状的试验数据不完全符合统计分析要求。 (4)以18一599(红)x R15组合的6个世代为材料，研究了幼胚培养胚性愈伤组织诱导率性状的基因效应，结果表明该性状表现为加性一显性一上位性遗传模型，但在模型中没有检测到显著〔h]和【11的存在，且它们的基因效应值均为负值，上位性效应[i]和【j」相对加性基因效应〔d]来说，仅为1/3左右。 (5)以18一599(红)‘R15组合的F:分离群体为作图群体，构建了75个SSR标记位点的遗传连锁图谱，分别覆盖了玉米基因组16O5cM和16OgcM，平均图距约21cM.利用FZ:，群体将胚性愈伤组织诱导率的8个QTL定位于第2、3、5、6和7染色体上，其中位于第5和6染色体上的第5一7个QTL位点的贡献率达到3佩以上，显然是控制该性状的3个主效QTL;除第4个和第7个QTL为部分显性外，其余QTL位点均为超显性;除位于第5染色体上的第5个QTL的显性效应为正值外，其余QTL的显性效应均为负值，这与前面常规数量遗传研究方法的研究结果是相当一致的。本研究将胚性愈伤组织绿苗发生数的5个QTL定位于第2、3、5、和6染色体上，位于第2、5和6染色体上的第1、4和5个QTL位点的贡献率高达60%以上，无疑是控制该性状的3个主效QTL;除位于第3染色体上的第2和3个QTL分别为部分显性和加性基因效应外，其余QTL位点均为超显性;对该性状QTL的显性效应则全为正值，与前述常规数量遗传研究方法的分析结果是不一致的，原因有待进一步研究。度量玉米幼胚培养能力的2个性状都存在贡献率相当大的主效QTL，这不仅与前面更多还原

【Abstract】 It is because that the excellent acceptors for maize transgenic engineering are insufficient in our country, especially in the southwest mountain areas of china andhereditary variation regularity for the two characters such as efficiency of embryonic callus induction and number of regenerating plant (these two characters were abbreviated to the nduction efficiency and number of regenerating in the following of the paper, respectively), which hint the maize culturing capacity, is not very clear. Therefore, aiming at picking out superior acceptors, we had made systematic researches on the two characters with combing traditional quantitative-character genetic analyzing methods such as single-factor genetic mating design, diallel crossing genetic design, genetic effect analyzing method and the modern molecular locating method such as QTLs’. The main results are followed.(1) 50 superior inbred lines and about 30 crosses in our country, especially in the southwest of China were used for identifying and selecting the superior genotypes in the above two investigated characters under the same culturing condition in 2000 and 2001. There was very significant difference among the genotypes in the both characters. But the two characters were not certainly related. Some genotypes such as 18-599(hong) and 18-599(bai) were very good in them. For some ones such as zong 31, induction was higher than 18-599(hong) and 18-599(bai) in the efficiency, but it was only 1/3 to the later in regenerating number. In some genotypes such as S37, R08, R15, PI38, A318, induction efficiency was just about 3% and scarcely any regenerating plants were got. On the whole, hybrids acted better than inbreeds in the both characters.(2) Two kind of inbreeds were selected as parents of the Grifflng’s method 1. 18-599(hong) and 18-599(bai) and the inbred line zong 31 are one kind because they are not only superior in the characters of maize cross breeding, such as CA, resistance to disease and the important agricultural characters, but also excellent in transformation characters as the induction and regeneration. A318, P138 and R15 were taken as the other kind as they are good in crossbreeding, but bad in the transformation. According to Griffmg’s method 1, diallel crossing was built and CA was analyzed. Variance analysis showed that there were the greatly significant difference among the both of GCA in inbreeds and SCA in crosses, respectively. The high GCA of 18-599(hong) and 18-599(bai) and the low SCA variance of their crosses showed the strong and stable heredity on the both characters. Taking them as parents, the generations with high and stable induction and regeneration will be gotten. As for inbreed zong 31, although GCA of induction frequency was highest and GCA of regeneration number was the third, SCA variance of its cross was high. So the inbreed zong31 can be inherited strongly but not stable to its descendant. As for the other inbreeds such as A318, P138 and R15, the effect values of GCA were negative. In a word, the excellent inbred lines in maize cross breeding 18-599(hong) and 18-599(bai) are also the most prospective and valuable inbreeds for maize immature embryo culture in this research.(3) In the analysis of the diallel crossing genetic mating design, Hayman’s genetic analyzing method was also taken into for exploring the genetic model of the above two culture characters (induction efficiency and number of regenerating). Additive-dominance genetic model was found to be functional to the nduction efficiency. Dominant effect is from partial to complete and most of them act minus. As for the number of regenerating, the results from two testing methods of the regression analysis based on the data of Wr and Vr ,and the variance analysis based on the data Wr+Vr and Wr-Vr were not certain.Linkage or other complicated things may be existed for this character. It is also possible due to the fewer parents in this diallel crossing, or that the datum for this character is not perfectly according with the basic need of the statistics更多还原