【作者】 蒋守华；

【导师】 邓德祥；

【作者基本信息】 扬州大学 ， 作物遗传育种， 2004， 硕士

【摘要】 玉米是我国主要农作物之一，在我国的国民经济发展中发挥重大作用。长期以来，玉米种质资源贫乏是我国玉米育种的突出问题，尤其是畜牧业的快速发展，更体现了饲料玉米种质的欠缺，所以有必要补充新的种质，扩大种质资源的利用。 玉米多叶型材料是从美国引进的一种新型种质，穗上叶片数较多，一般可达8～25叶，叶片上冲，株型紧凑，茎秆粗壮，根系发达。本研究以多叶材料的6组自交系（按穗上叶片数的不同，每个自交系分为8叶、9叶、10叶、11叶、12叶）为亲本，采用6×6不完全双列杂交法共配制75个杂交组合（只包括F₁的正交），分析了多叶玉米主要性状的配合力、平均优势及相关性。结果如下： （1）6个自交系不完全双列杂交得到75个组合（正交），亲本和杂种F₁的方差差异极显著，表明多叶玉米是受基因型的遗传基础控制。 （2）一般配合力效应分析结果表明，同一性状不同的叶片数，或同一组合不同性状之间的配合力效应都有差异，其遗传特性在不同的穗上叶片数间有差异，表明配合力应结合具体的穗上叶片数才能进行评价。本研究中，叶片数为11叶的自交系Y₅₃在农艺性状、品质性状和产量上表现较大的效应，同理在自交系P₁₇₅中，12叶表现较好，而在自交系P₁₉、P₈₅、J_7-3和M₇的不同叶片数中各个效应值大多是负向的，说明由其组配的后代在各个性状上有下降的趋势。 （3）对75个组合主要性状进行相关分析可知，不同叶片数间的各个性状的相关性表现不同的差异。在叶片数为8叶、9叶、10叶、11叶和12叶的组合中除12叶，其它4组叶片数的株高和穗位高与生物学产量均呈极显著的正相关，其它各个性状与生物学产量之间均无显著相关性。在叶片数为8叶中，株高、产量与粗淀粉相关系数较大；在10叶中，穗位高与粗淀粉和粗纤维之间均表现极显著的相关性；在11叶上，株高与粗纤维，百粒重与粗淀粉之间均呈极显著的相关;在12叶上，百粒重与粗纤维之间表现正相关;表明穗上叶片数为8、9、10和11叶的自交系具有培育青贮玉米的潜力。 （4）本研究所使用的核遗传背景不同的6个多叶玉米自交系系列，通过配合力分析及杂种优势的研究，初步筛选出一个高产、优质的组合即穗上叶为n叶的Y53 xP:75，这个组合对选育青饲青贮型玉米提供了新的种质，同时也促进了畜牧业更快更好地发展。更多还原

【Abstract】 Maize is one of the main crops, which plays an important role in the national economic development. For a long time, lacking of germplasm resources was the leading problem of the maize breeding in our country. The fast development of livestock has a big demand on embodied germplasms of forage maize,which were deficient especially, So it is necessary to add new germplasm and expand use of germplasm resources.Leafy maize material is a new-type of germplasm derived from U.S.A, leafy maize had 8-25 leaves above the ear, and better stalk strength much taller than non-leafy maize and more flourishing root, their stem stalk was stalwart, their resistance was strong synthetically. This study was conducted by 6 inbred lines and 75 hybrid as materials which were from incomplete diallel cross of 6 groups of leafy maize (According to different leaf numbers above the ear, inbred lines were divided into 8 leaves, 9 leaves, 10 leaves, 11 leaves, 12 leaves). Analyses were made for the combining ability, average heterosis and correlaton of the main characters of leafy maize. The results were as follows:(1)The difference among parents and FI was very remarkable . It indicated that leafy character was controlled by the hereditary of the genotypes.(2)Analysis of GCA effect showed that the difference of combining ability effect value existed in different leaves of the same characters, or different characters of the same combination . Hereditary character of GCA effect had difference in different leaves above the ear, it indicated that combining ability should be evaluated according the different leafy group. In this study, the inbred line Y53 of 11 leaves above the ear showed good effect relatively at agricultural characters, quality characters and yield. Similarly, the inbred line P175, with 12 leaves above the ear, showed better, but different leaves of inbred lines P19, P85 , J7-3 and M7, whose effectswere negative mostly, this showed the generation crossed by them can be weakened on each character.(3)Through relativity analysis of the main characters of 75 combinations ,we can know, the relativity of each character in different leaves was different. Except for 12 leaves , in 8, 9, 10,11 and 12 leaves of combinatins above the ear,, the relativity of plant-height and biological yield, ear-height and biological yield was high, there was not remarkable relativity between other characters and biological yield. In 8 leaves above the ear, relativities of height, biological yield and crude starch were much strong; In 10 leaves, there was extremely remarkable relativity between crude starch , crude fibre and ear-height; In 11 leaves, plant-height and crude fibre, 100-grain weight and crude starch showed extremely remarkable; In 12 leaves, there was positively relevant between 100-grain weight and crude fibre; Those indicated that inbred lines of 8, 9, 10 and 11 leaves above the ear had the potentiality on cultivating silage maize.(4) 6-leafy maize series,with different hereditary background of maize,were used by the study of their combining ability and heterosis,we obtained 53*PI75 above the 11 leaves of ear,which had high-yield, high-quality characters elementarily. This combination can be used as a new variety of silage maize,it could also promote livestock to develop better and faster .更多还原