Development of introgression lines in high yielding, semi-dwarf genetic backgrounds to enable improvement of modern rice varieties for tolerance to multiple abiotic stresses free from undesirable linkage drag

Abstract

Occurrence of multiple abiotic stresses in a single crop season has become more frequent than before. Most of the traditional donors possessing tolerance to abiotic stresses are tall, low-yielding with poor grain quality. To facilitate efficient use of complex polygenic traits in rice molecular breeding research, we undertook development of introgression lines in background of high-yielding, semi-dwarf varieties with good grain quality. The study reports the development and evaluations of over 25,000 introgression lines in eleven elite rice genetic backgrounds for improvement of yield under multiple abiotic-stresses such as drought, flood, high/low temperature. The developed introgression lines within each genetic background are near isogenic/recombinant inbred lines to their recipient recurrent parent with 50 to 98% background recovery and additionally carry QTLs/genes for abiotic stresses. The multiple-stress tolerant pyramided breeding lines combining high yield under normal situation and good yield under moderate to severe reproductive-stage drought, semi-dwarf plant type with good grain quality traits have been developed. The introgression lines in dwarf backgrounds open new opportunity to improve other varieties without any linkage drag as well as facilitate cloning of QTLs, identification and functional characterization of candidate genes, mechanisms associated with targeted QTLs and the genetic networks underlying complex polygenic traits.

Molecular Breeding for Improving Productivity of Oryza sativa L. cv. Pusa 44 under Reproductive Stage Drought Stress through Introgression of a Major QTL, qDTY12.1

“…Furthermore, its prevalence among 85% of the random drought cultivars is remarkable, and evidence indicates that other cereal genomes carry homologous sequences to this QTL [ 33 ]. Due to its versatility, qDTY12.1 has been a choice QTL for introgression into multiple backgrounds across the globe for improved RSDS tolerance [ 14 ] and is known to integrate high grain yields under mild to severe stress conditions.…”

“…Among these, prominent QTLs such as qDTY1.1 [ 9 , 10 ], qDTY3.1 [ 11 ] and qDTY12.1 [ 12 ] have been used for marker-assisted improvement of several elite rice cultivars that are drought sensitive. Currently, improved cultivars having qDTYs either singly or in combination have already been released in several countries [ 13 , 14 ].…”

QTL Analysis of Five Morpho-Physiological Traits in Bread Wheat Using Two Mapping Populations Derived from Common Parents

“…Several studies have been successfully conducted using F 2 or F 2 -derived F 3 populations to identify major QTLs in bread wheat [17][18][19], durum wheat [20], rice [21], maize [22], and other species [23][24][25][26]. However, unfortunately, F 2 and BC are temporary populations.…”

Assessment of genetic variability, heritability and genetic advance of biparental progenies in okra [Abelmoschus esculentus (L.) Moench]

“…Many breeding methodologies suited the need and production of biparental progenies in the early segregating generation is one such approach which is most effective in breaking the undesirable linkages and in obtaining desirable recombinants. (Kumar et al 2020) In view of the above facts, the current study aimed to compare the output of biparental progenies with the F2 generation of single and double cross populations of Bhendi.…”