Identification of a novel hybrid sterility locus S67 between temperate japonica subgroup and basmati subgroup in Oryza sativa L.

Asian cultivated rice (Oryza sativa L.) is the most important cultivated species in the AA genome species of the genus Oryza. basmati is a special and famous subgroup in Asian cultivated rice, and temperate japonica is one of the most important cultivated subgroup, too.

Improving bridge effect to overcome interspecific hybrid sterility by pyramiding hybrid sterile loci from Oryza glaberrima.

In order to evaluate the genetic effect caused by hybrid sterile loci, NILs with O. glaberrima fragment at six hybrid sterile loci under O. sativa genetic background (single-locus-NILs) were developed; two lines harboring two hybrid sterile loci, one line harboring three hybrid sterile loci were further developed.

Three QTL from Oryza meridionalis Could Improve Panicle Architecture in Asian Cultivated Rice.

Rice panicle architecture is directly associated with grain yield and is also the key target in high-yield rice breeding program. In this study, three BCF segregation populations derived from the crosses between two accessions of Oryza meridionalis and a O. sativa spp.

Interspecific Hybridization Is an Important Driving Force for Origin and Diversification of Asian Cultivated Rice L.

As one of the most important crops, Asian cultivated rice has evolved into a complex group including several subgroups adapting various eco-climate-systems around the globe. Here, we pictured a comprehensive view of its original domestication, divergences, and the origin of different subgroups by integrating agriculture, archeology, genetics, nuclear, and cytoplasm genome results. Then, it was highlighted that interspecific hybridization-introgression has played important role in improving the genetic diversity and adaptation of during its evolution process.

Understanding the Nature of Hybrid Sterility and Divergence of Asian Cultivated Rice.

Intraspecific hybrid sterility is a common form of postzygotic reproductive isolation in Asian cultivated rice, which is also the major obstacle to utilize the strong heterosis in the rice breeding program. Here, we review recent progress in classification and hybrid sterility in Asian cultivated rice. A genome-wide analysis of numerous wild relatives of rice and Asian cultivated rice has provided insights into the origin and differentiation of Asian cultivated rice, and divided Asian cultivated rice into five subgroups.

A Genetic Resource for Rice Improvement: Introgression Library of Agronomic Traits for All AA Genome Species.

Rice improvement depends on the availability of genetic variation, and AA genome species are the natural reservoir of favorable alleles that are useful for rice breeding. To systematically evaluate and utilize potentially valuable traits of new QTLs or genes for the Asian cultivated rice improvement from all AA genome species, 6,372 agronomic trait introgression lines (ILs) from BC to BC were screened and raised based on the variations in agronomic traits by crossing 170 accessions of 7 AA genome species and 160 upland rice accessions of as the donor parents, with three elite cultivars of , Dianjingyou 1 (a variety), Yundao 1 (a variety), and RD23 (an variety) as the recurrent parents, respectively. The agronomic traits, such as spreading panicle, erect panicle, dense panicle, lax panicle, awn, prostrate growth, plant height, pericarp color, kernel color, glabrous hull, grain size, 1,000-grain weight, drought resistance and aerobic adaption, and blast resistance, were derived from more than one species.

Mapping five novel interspecific hybrid sterility loci between and .

is a potential source for improving Asian cultivated rice via direct hybridization and backcrossing. However, hybrid sterility between and is the main barrier of reproduction hindering the transfer of favorable genes from to . To investigate the nature of hybrid sterility between and , three accessions of were used as male parents to cross Dianjingyou 1, an subsp.

Neutral alleles at hybrid sterility loci of from AA genome relatives in Genus .

Hybrid sterility between and is a main reproduction barrier when transferring the favorable alleles from to and it happens due to allelic interaction at sterility loci. Neutral alleles at each locus have the potential to overcome the sterility between the two cultivated rice species. In this study, an cultivar Dianjingyou 1 (DJY1) and its near-isogenic lines (NILs) harboring the single sterility allele -glab, -glab, -glab, -glab, -glab and -glab as the tested lines were crossed with , , , , , and so as to detect the neutral alleles of these loci.

Mapping three new interspecific hybrid sterile loci between Oryza sativa and O. glaberrima.

Hybrid sterility hinders the transfer of useful traits between Oryza sativa and O. glaberrima. In order to further understand the nature of interspecific hybrid sterility between these two species, a strategy of multi-donors was used to elucidate the range of interspecific hybrid sterility in this study.

Analysis of elite variety tag SNPs reveals an important allele in upland rice.

Elite crop varieties usually fix alleles that occur at low frequencies within non-elite gene pools. Dissecting these alleles for desirable agronomic traits can be accomplished by comparing the genomes of elite varieties with those from non-elite populations. Here we deep-sequence six elite rice varieties and use two large control panels to identify elite variety tag single-nucleotide polymorphism alleles (ETASs).

Cytoplasm affects grain weight and filled-grain ratio in indica rice.

Background: Cytoplasmic effects on agronomic traits--involving cytoplasmic and nuclear genomes of either different species or different cultivars--are well documented in wheat but have seldom been demonstrated in rice (Oryza sativa L.). To detect cytoplasmic effects, we introgressed the nuclear genomes of three indica cultivars--Guichao 2, Jiangchengkugu, and Dianrui 449--into the cytoplasms of six indica cultivars - Dijiaowujian, Shenglixian, Zhuzhan, Nantehao, Aizizhan, and Peta.