Comparative transcriptome analysis reveals a rapid response to phosphorus deficiency in a phosphorus-efficient rice genotype
M. Asaduzzaman Prodhan, Juan Pariasca‐Tanaka, Yoshiaki Ueda, Patrick E. Hayes, Matthias Wissuwa
Abstract
Phosphorus (P) is an essential plant nutrient. Most rice growing lands lack adequate P, requiring multiple P fertiliser applications to obtain expected yields. However, P fertiliser is environmentally damaging, and already unaffordable to the marginal farmers. This warrants developing P-efficient rice varieties that require less P to produce the expected yield. However, genetic factors underlying P-use efficiency (PUE) in rice remain elusive. Here, we conducted comparative transcriptome analysis using two rice varieties with contrasting PUE; a P-efficient landrace DJ123 and a P-inefficient modern cultivar IR64. We aimed to understand the transcriptomic responses in DJ123 that allow it to achieve a high PUE under low P conditions. Our results showed that both DJ123 and IR64 had replete tissue P concentrations after 48 h of P deprivation. Yet, DJ123 strongly responded to the external low P availability by inducing P starvation-inducible genes that included SPX2, PHO1, PAPs and SQDs, while these genes were not significantly induced in IR64. We envisage that the ability of DJ123 to rapidly respond to low P conditions might be the key to its high PUE. Our findings lay a valuable foundation in elucidating PUE mechanism in rice, thus will potentially contribute to developing P-efficient modern rice variety.