GM rice thrives in poor soils

Wild rice gene gives yield boost
By Richard Black, Environment correspondent, BBC News
A gene from wild Indian rice plants can significantly raise the yield of common varieties in nutrient-poor soils.
Scientists from the International Rice Research Institute (Irri) identified a gene that helps uptake of phosphorus, nitrogen and potassium, and transferred it into commercial strains.
Their yield was about 60% above normal in phosphorus-poor soils, the team reports in the journal Nature.
Large swathes of Asia have soil that is phosporus-deficient...
...It took the Irri team three years to identify the gene responsible, which they have named PSTOL1.
"We got the [DNA] sequence of this region, but the region is very complex and it was very difficult to identify what is an actual gene and what is not," lead researcher Sigrid Heuer told BBC News.
"There's so much work being done on phosphorus pathways and we could never find the genes and the mechanisms, and actually it's very simple - the gene promotes larger root growth, so the plant takes up nutrients more easily...

The protein kinase Pstol1 from traditional rice confers tolerance of phosphorus deficiency
Rico Gamuyao, Joong Hyoun Chin, Juan Pariasca-Tanaka, Paolo Pesaresi, Sheryl Catausan, Cheryl Dalid, Inez Slamet-Loedin, Evelyn Mae Tecson-Mendoza, Matthias Wissuwa & Sigrid Heuer
Nature 488, 535–539 (23 August 2012) doi:10.1038/nature11346
Received 23 November 2011 Accepted 25 June 2012 Published online 22 August 2012
As an essential macroelement for all living cells, phosphorus is indispensable in agricultural production systems. Natural phosphorus reserves are limited1, and it is therefore important to develop phosphorus-efficient crops. A major quantitative trait locus for phosphorus-deficiency tolerance, Pup1, was identified in the traditional aus-type rice variety Kasalath about a decade ago2, 3. However, its functional mechanism remained elusive4, 5 until the locus was sequenced, showing the presence of a Pup1-specific protein kinase gene6, which we have named phosphorus-starvation tolerance 1 (PSTOL1). This gene is absent from the rice reference genome and other phosphorus-starvation-intolerant modern varieties7, 8. Here we show that overexpression of PSTOL1 in such varieties significantly enhances grain yield in phosphorus-deficient soil. Further analyses show that PSTOL1 acts as an enhancer of early root growth, thereby enabling plants to acquire more phosphorus and other nutrients. The absence of PSTOL1 and other genes—for example, the submergence-tolerance gene SUB1A—from modern rice varieties underlines the importance of conserving and exploring traditional germplasm. Introgression of this quantitative trait locus into locally adapted rice varieties in Asia and Africa is expected to considerably enhance productivity under low phosphorus conditions.