Alonso-Blanco C, Blankestijn-de Vries H, Hanhart C J, Koornneef M
Graduate School Experimental Plant Science, Laboratory of Genetics, Wageningen Agricultural University, Dreijenlaan 2, 6703 HA Wageningen, The Netherlands.
Proc Natl Acad Sci U S A. 1999 Apr 13;96(8):4710-7. doi: 10.1073/pnas.96.8.4710.
We have analyzed two Arabidopsis strains differing in the mean seed size and seed number they produced. The accession Cape Verde Islands (Cvi) yielded on average about 40% fewer seeds than the laboratory strain Landsberg erecta (Ler), but Cvi seeds were almost twice as heavy. Maternal and nonmaternal genetic factors were involved in the seed size variation, and interactions between both types of factors presumably occurred. The Ler/Cvi seed size difference increased through seed development from ovule maturation until seed desiccation, suggesting that multiple processes of seed development were affected. In addition, it involved changes in the final cell number and cell size of the seed coat and the embryo. Cell number variation was controlled mainly by maternal factors, whereas nonmaternal allelic variation mostly affected cell size. By using a recombinant inbred line population derived from Ler and Cvi, we mapped quantitative trait loci (QTLs) affecting 12 life history traits related to seed size, fruit size, seed number, and plant resources. Five of the seed size QTLs colocated with QTLs for other traits, suggesting that they control seed size via maternal components affecting ovule number and/or carpel development, ovule development, or reproductive resource allocation in the mother plant. The six remaining putative seed size QTLs did not show a significant effect on any other trait, suggesting that this allelic variation may be involved specifically in seed development processes.
我们分析了两种拟南芥品系，它们在产生的平均种子大小和种子数量上存在差异。佛得角群岛（Cvi）品系产生的种子平均比实验室品系直立型兰茨贝格（Ler）少约40%，但Cvi种子的重量几乎是Ler种子的两倍。种子大小的变异涉及母本和非母本遗传因素，并且这两种因素之间可能存在相互作用。从胚珠成熟到种子干燥的种子发育过程中，Ler/Cvi种子大小的差异不断增大，这表明种子发育的多个过程受到了影响。此外，它还涉及种皮和胚最终细胞数量和细胞大小的变化。细胞数量的变异主要由母本因素控制，而非母本等位基因变异大多影响细胞大小。通过使用由Ler和Cvi衍生的重组自交系群体，我们定位了影响与种子大小、果实大小、种子数量和植物资源相关的12个生活史性状的数量性状基因座（QTL）。其中五个种子大小QTL与其他性状的QTL共定位，这表明它们通过影响胚珠数量和/或心皮发育、胚珠发育或母本植物生殖资源分配的母本成分来控制种子大小。其余六个假定的种子大小QTL对任何其他性状均未表现出显著影响，这表明这种等位基因变异可能专门参与种子发育过程。
