4个陆地棉F₂群体农艺和经济性状的QTL定位

李洪戈^?，潘兆娥^?，何守朴，贾银华，耿晓丽，陈保军，王立如，庞保印，杜雄明^*

摘要：

背景：陆地棉（Gossypium hirsutum）以其丰产性而产量占到世界棉花总产量的90%以上。然而，产量性状和纤维品质性状通常呈现负相关。本研究利用2个陆地棉常规品系（4133B和SGK9708）和2个陆地棉渐渗系（苏远04-3和J02-247）构建出4个F₂群体，4133B和SGK9708丰产性好但是纤维品质一般，而渐渗系苏远04-3和J02-247的纤维品质较优。结合8个农艺经济性状表型数据对产量和纤维品质进行了QTL定位，并对其遗传基础进行解析。

结果：在分离群体中，存在广泛的表型变异和超亲分离现象。针对4个F₂群体分别构建了4个遗传图谱，其长度分别为585.97 cM、752.45 cM、752.45 cM 和 1163.66 cM。在4个群体中共鉴定到50个QTLs，其中株高7个，纤维品质27个，纤维产量16个。某些QTLs能在不同群体中重复发现，如qBW4和qBW2与同一个SSR标记NAU1255连锁。此外，在4133B × 苏远04–3群体的连锁群9上发现一个QTL簇，该QTL簇包含8个QTLs，对应6个性状。

结论：本研究结果将为探究棉花产量和纤维品质同步改良的遗传基础提供新的视角。

关键词：陆地棉，产量性状，纤维品质性状，QTL定位，同步改良

Journal of Cotton Research. 2021, 4: 3

https://doi.org/10.1186/s42397-020-00076-y

https://jcottonres.biomedcentral.com/articles/10.1186/s42397-020-00076-y#rightslink

QTL mapping of agronomic and economic traits for four F₂populations of upland cotton

LI Hongge, PAN Zhaoe, HE Shoupu, JIA Yinhua, GENG Xiaoli, CHEN Baojun, WANG Liru, PANG Baoyin & DU Xiongming 

Background

Upland cotton (Gossypium hirsutum) accounts for more than 90% of the annual world cotton output because of its high yield potential. However, yield and fiber quality traits often show negative correlations. We constructed four F2 populations of upland cotton, using two normal lines (4133B and SGK9708) with high yield potential but moderate fiber quality and two introgression lines (Suyuan04–3 and J02–247) with superior fiber quality, and used them to investigate the genetic basis underlying complex traits such as yield and fiber quality in upland cotton. We also phenotyped eight agronomic and economic traits and mapped quantitative trait loci (QTLs).

Results

Extensive phenotype variations and transgressive segregation were found across the segregation populations. We constructed four genetic maps of 585.97 centiMorgan (cM), 752.45 cM, 752.45 cM, and 1 163.66 cM, one for each of the four F2 populations. Fifty QTLs were identified across the four populations (7 for plant height, 27 for fiber quality and 16 for yield). The same QTLs were identified in different populations, including qBW4 and qBW2, which were linked to a common simple sequence repeat (SSR) marker, NAU1255. A QTL cluster containing eight QTLs for six different traits was characterized on linkage group 9 of the 4133B × Suyuan04–3 population.

Conclusions

These findings will provide insights into the genetic basis of simultaneous improvement of yield and fiber quality in upland cotton breeding.