Wang Sheng-Shan, Chen Rong-Kuen, Chen Kai-Yi, Liu Chu-Yin, Kao Shu-Min, Chung Chia-Lin
Tainan District Agricultural Research and Extension Station, No. 70, Pasture, Xinhua, Tainan 71246, Taiwan.
Department of Agronomy, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan.
Breed Sci. 2017 Sep;67(4):340-347. doi: 10.1270/jsbbs.17007. Epub 2017 Jul 28.
Secondary branch number (SBN) is an important component affecting spikelet number per panicle (SPP) and yield in rice. During recurrent backcross breeding, four BCF populations derived from the high-yield donor parent IR65598-112-2 and the recurrent parent Tainan 13 (a local cultivar) showed discontinuous variations of SPP and SBN within populations. Genetic analysis of 92 BCF individuals suggested that both SPP and SBN are controlled by a single recessive allele. Two parents and 37 BCF individuals showing high- and low-SBN type phenotypes were analyzed by restriction-site associated DNA sequencing (RAD-seq). Based on 2,522 reliable SNPs, the was mapped to a distal region of the long arm of chromosome 7. Trait-marker association analysis with an additional 166 high-SBN type BCF individuals and 8 newly developed cleaved amplified polymorphic sequence markers further delimited the locus to a 601.4-kb region between the markers SNP2788 and SNP2849. Phenotype evaluation of two BCF backcross inbred lines revealed that increased SPP by 83.2% and SBN by 61.0%. The of IR65598-112-2 could be used for improving reproductive sink capacity in rice.
二次枝梗数（SBN）是影响水稻每穗颖花数（SPP）和产量的重要组成部分。在回交育种过程中，来自高产供体亲本IR65598 - 112 - 2和轮回亲本台南13（一个地方品种）的四个BCF群体在群体内表现出SPP和SBN的不连续变异。对92个BCF个体的遗传分析表明，SPP和SBN均由单个隐性等位基因控制。通过限制性位点关联DNA测序（RAD-seq）对两个亲本和37个表现出高SBN型和低SBN型表型的BCF个体进行了分析。基于2522个可靠的单核苷酸多态性（SNP），将其定位到7号染色体长臂的远端区域。利用另外166个高SBN型BCF个体和8个新开发的酶切扩增多态性序列标记进行性状-标记关联分析，进一步将该位点限定在标记SNP2788和SNP2849之间的601.4 kb区域。对两个BCF回交自交系的表型评价表明，该基因使SPP增加了83.2%，SBN增加了61.0%。IR65598 - 112 - 2的该基因可用于提高水稻的生殖库容量。
