Novel major QTLs associated with low soil phosphorus tolerance identified from the Indian rice landrace, Wazuhophek

Abstract

With an objective of mapping novel low soil P (Phosphorus) tolerance loci in the non-Pup1 type donor rice line, Wazuhophek, we screened a recombinant inbred line (RIL) mapping population consisting of 330 lines derived from the cross Wazuhophek x Improved Samba Mahsuri (which is highly sensitive to low soil P) in a plot with low soil P for tolerance associated traits. Molecular mapping with SSR markers revealed a total of 16 QTLs (seven major and nine minor QTLs), which are associated with low soil P tolerance related traits. Interestingly, a QTL hotspot, harbouring 10 out of 16 QTLs were identified on the short arm of chromosome 8 (flanked by the makers RM22554 and RM80005). Five major QTLs explaining phenotypic variance to an extent of 15.28%, 17.25%, 21.84%, 20.23%, and 18.50%, associated with the traits, plant height, shoot length, the number of productive tillers, panicle length and yield, respectively, were located in the hotspot. Two major QTLs located on chromosome 1, associated with the traits, total biomass and root to shoot ratio, explaining 15.44% and 15.44% phenotypic variance, respectively were also identified. Complex epistatic interactions were observed among the traits, grain yield per plant, days to 50% flowering, dry shoot weight, and P content of the seed. In-silico analysis of genomic regions flanking the major QTLs revealed the presence of key putative candidate genes, possibly associated with tolerance.

QTL mapping for early root and shoot vigor of upland rice (Oryza sativa L.) under P deficient field conditions in Japan and Madagascar

“…Further investigations are necessary to determine if qPef6 is related with root elongation and if such trait is relevant with P uptake and shoot growth under P-deficient field conditions. Another QTL detected by Kale et al. (2021) was located on chromosome 8, but seemingly towards the opposite end of chromosome from qRNO8 detected here.…”

“…Several QTL associated with tolerance to P deficiency have been detected in rice (Wissuwa et al, 1998;Shimizu et al, 2004;Koide et al, 2013;Kale et al, 2021), of which the most influential appears to be the Pup1 locus on chromosome 12 (Wissuwa et al, 1998;Wissuwa et al, 2002). Among these studies, Shimizu et al (2004) detected a QTL for P deficiency-induced root elongation under a hydroponic condition on chromosome 6 that appears to be overlapping with qPef6 detected here for SW and TW.…”

“…Several QTL associated with tolerance to P deficiency have been detected in rice ( Wissuwa et al., 1998 ; Shimizu et al., 2004 ; Koide et al., 2013 ; Kale et al., 2021 ), of which the most influential appears to be the Pup1 locus on chromosome 12 ( Wissuwa et al., 1998 ; Wissuwa et al., 2002 ). Among these studies, Shimizu et al.…”

Stacking of Pup1 QTL for low soil phosphorus tolerance and bacterial blight resistance genes in the background of APMS6B, the maintainer line of rice hybrid DRRH-3

“…The presence of phosphorus responsive gene OsPSTOL1 (Pup1) in introgressed lines facilitates the effectual root system like root length and root volume which in turn helps in improvement of grain yield under P deficit soil as reported by Gamuyao et al (2012) and Yugandhar et al (2017). Positive and significant association of root length and volume in derived lines noticed in terms of tolerance to low P and grain yield and similar observations were reported by earlier workers (Kale et al 2021). The Pup1 possessed lines with modified root architecture and morphology facilitate exploration and adaptive mechanism to access P beyond the rhizosphere when bioavailable P is limited under low P plot.…”

Identification of QTL Associated with Agro-Morphological and Phosphorus Content Traits in Finger Millet under Differential Phosphorus Supply via Linkage Mapping

“…Improving P use efficiency (PUE) and P acquisition efficiency (PAE) via molecular breeding will help improve plants' aboveground and belowground traits [18,21,22]. For many years, plant breeders have identified several quantitative trait loci (QTL) associated with plant biomass, root architecture, P content, and yield in cereals under LP stress [23][24][25][26][27]. A total of 16 QTL associated with plant height (PH), shoot length (SL), number of productive tillers (NPT), panicle length (PL), shoot dry weight (SDW), seed yield (SY), plant biomass, root-shoot ratio (RSR), and seed P content (SPC) were identified in rice (Oryza sativa) under LP conditions [24].…”