【作者】 李亚娟；

【导师】 梁康迳；

【作者基本信息】 福建农林大学 ， 作物遗传育种， 2003， 硕士

【摘要】 选用6个不同类型的水稻品种（系），按P（P+1）／2的双列杂交设计，人工组配成一套包括亲本（P）、F₁和F₂ 3个世代的遗传材料。采用包括种子、细胞质、母体植株三套遗传体系的种子性状遗传模型和统计分析方法，系统分析了稻米可溶性糖含量、全氮含量、糖氮比、糙米长、糙米宽、糙米厚、糙米长宽比、千粒重和直链淀粉含量等9个品质性状的遗传特点。主要结果如下： 遗传方差分析结果表明，除糖氮比和糙米长两性状不受细胞质基因的影响外，其余各品质性状的表现同时受到种子、细胞质、母体植株三套遗传体系的控制，其中可溶性糖含量和千粒重主要受制于二倍体母体植株核基因的显性效应；全氮含量、糖氮比主要受制于种子核基因的显性效应；糙米长、糙米宽、糙米长宽比主要受制于二倍体母体植株核基因效应，且以加性效应为主；糙米厚主要受制于种子核基因效应，且以加性效应为主；直链淀粉含量主要受制于二倍体母体植株核基因效应，且以加性效应为主。 遗传率和选择响应分析结果表明，可溶性糖含量、糖氮比、千粒重的遗传率较小或为零，对其进行选择不易奏效；糙米宽和糙米长宽比以母体狭义遗传率为主，对其进行单株选择效果较好；全氮含量和糙米厚以直接狭义遗传率为主，采用单粒选择易取得较好效果；糙米长、直链淀粉含量的直接狭义遗传率和母体狭义遗传率均较大，采用单粒选择为主，辅以单株选择能够取得较好效果。 杂种优势分析结果表明，稻米可溶性糖含量、糖氮比、糙米长、糙米宽和千粒重具有较强的正向杂种优势，其中以糙米宽的优势最大；全氮含量、糙米厚、糙米长宽比和直链淀粉含量具有较强的负向杂种优势，以糙米长宽比的负向优势最大。可溶性糖含量、全氮含量、糖氮比、糙米厚、糙米长宽比和千粒重以母体植株杂种优势为主，直链淀粉含量以种子直接杂种优势为主，糙米宽的种子直接优势和母体植株优势并重。 遗传协方差分析结果表明，提高可溶性糖含量，伴随着全氮含量和糖氮比的显著提高，糙米长、千粒重和直链淀粉含量的显著降低；提高全氮含量可能会显著提高糙米厚和直链淀粉含量，而糖氮比、糙米长和千粒重随之显著降低；随着糖氮比的提高，糙米厚、千粒重和直链淀粉含量将显著降低；糙米长的提高将伴随着千粒重、糙米长宽比的提高和糙米宽、糙米厚的降低；增加糙米宽会提高糙米厚、千粒重、直链淀粉含量，降低糙米长宽比；随着糙米厚的增加千粒重会显著提高，糙米长宽比和直链淀粉含量会显著降低；减小长宽比，将伴随着千粒重和直链淀粉含量降低；提高千粒重，也随着提高直链淀粉含量。 Lemont、早恢89和02428可以明显降低或提高杂种后代的可溶性糖含量；早恢89和02428可显著降低或提高杂交稻糖氮比；Lemont可在粒型改良中用作优良亲本；以Lemont、早恢89、粳籼89、佳禾早占为亲本的后代，籽粒宽度明显减小。更多还原

【Abstract】 Analysis on seed, cytoplasmic and maternal genetic effects for soluble sugar content (SSC), total nitrogen content (TNC), ratio of sugar to nitrogen (RSN), brown rice length (BRL), brown rice width (BRW), brown rice thickness (BRT), ratio of length to width of brown rice (RLW), 1000-grain weight (GW) and amylose content (AC) was conducted by using genetic models for quantitative traits of seed in cereal crops. According to complete diallel cross design, parents, F| and Fa genetic generations derived from six different types of rice varieties (parental lines), were used for this experiment. The main results were as follow.Analysis on genetic variance showed that all the traits involved were controlled by genes of seed, cytoplasmic and maternal plant simultaneously. SSC and GW were mainly affected by dominant effects of diploid maternal nuclear genes, while TNC and RSN by dominant effects of seed nuclear genes. BRL, BRW, RLW and AC were mainly controlled by genetic effects of nuclear genes of diploid maternal plant, of which additive effects were considered main genetic factor. BRT was primarily governed by genetic effects of seed nuclear genes, of which additive effects were taken as main genetic factor.The results of heritabilities analysis indicated that heritabilities for SSC, RSN and GW were small or depressive, implying that selection for them might be invalid. Maternal heritability in narrow sense was the main heritability for BRW and RLW, both of them could be improved by single-plant selection, while direct heritability for TNC and BRT appeared to be larger, for which single seed descent method might be better in genetic selection. Both direct heritability and maternal one in narrow sense for BRL and AC tended to be higher, showing both traits could be improved mainly by the method of single-seed descent, complemented with’ single-plant selection.Based on heterosis analysis, it was indicated that SSC, RSN, BRL, BRW and GW in hybrid seeds appeared to be increased significantly but TNC, BRT, RLW and AC in hybrid seeds tendedto be decreased markedly, of which increased range of BRW was the largest and that of RLW was the lowest. It was also found that maternal heterosis for SSC, TNC, RSC, BRT, RLW and GW played main roles, direct heterosis for AC was considered as the main effect, both direct heterosis and maternal one for BRW were main genetic factors.Analysis on genetic covariance proved to be helpful to elucidate indirect relationship between paired traits. It was showed that increasing SSC might contribute to significant increase of TNC and RSN and decrease of BRL, GW and AC simultaneously. Increasing TNC might result in increases of BRW and AC and decreases of RSN, BRL and GW simultaneously. Increase of RSN might significantly lead to decline of BRW, GW and AC. Increase of BRL might increase GW and RLW and reduce BRW and BRT significantly at the same time. Increase of BRW might indirectly enhance BRT, GW and AC and decrease RLW. Increase of BRT would significantly induce increase of GW and decrease of RLW and AC, as well. Decrease of RLW might decline GW and AC while decrease of AC might be attributed to increase of GW indirectly.The prediction of seed, cytoplasm and maternal genetic effects of six parental lines indicated that Lemont, ZaoHui 89 or 02428 could be selected as elite parents to increase or decrease SSC of their progenies, respectively, and ZaoHui 89 or 02428 were considered as better lines to increase or decrease RSN, and Lemont could be used to improve grain shape. Progenies with significantly decreased BRW were predicted in genetic populations derived from. The crosses among the parents including Lemont, ZaoHui 89, Jingxian 89 and Jiahezaozhan.更多还原