QTL pyramiding leads to enhanced seeding establishment through improved germinability at low temperatures in rice.

Satoh, Tomohiro; Kawamoto, Tomohiko; Takahashi, Hidekazu; Watanabe, Akio; Ueda, Kenji; Sakurai, Kenji; Akagi, Hiromori

Low-temperature germinability is a crucial trait for seedling establishment at low temperatures, which is essential for the direct sowing culture of rice. We pyramided four QTLs for germinability at low temperature in the genetic background of the Japanese cultivar Akitakomachi. In the QTL pyramiding lines, the accumulated QTLs additively increased the low-temperature germination rate, despite the weak effects of individual QTLs. In addition, qLTG3-2, which alone did not increase the germination rate at low temperature, was found to further enhance the germination rate when combined with either qLTG3-1 or qLTG11-1. Low-temperature germinability improved remarkably in proportion to the number of QTLs accumulated. Thus, QTL pyramiding is an effective method for improving this trait. Furthermore, improved low-temperature germinability in the lines accumulating the four QTLs also led to enhanced seedling establishment compared to Akitakomachi. Seedling establishment at low temperature is a complex trait involving continuous growth from seed germination to seedling development. The remarkable improvement in low-temperature germinability is likely to contribute to the improved seedling establishment at low temperature. However, the four QTL pyramiding line exhibited a reduced appearance quality of brown rice. To avoid the introduction of undesirable traits, pyramiding using a new QTL for low-temperature germinability is expected to develop superior rice variety suitable for direct sowing cultivation.

LOCUS (Genetics); BROWN rice; LOW temperatures; RICE quality; GERMINATION

Euphytica, 2024, Vol 220, Issue 11, p1

0014-2336

Academic Journal

10.1007/s10681-024-03422-2