Pemetaan, Karakterisasi, dan Pengembangan Primer-primer Lokus Pup1 (P uptake 1) pada Padi untuk Peningkatan Toleransi terhadap Defisiensi Fosfor

Phosphorus (P) is the second most important nutrient for plants after nitrogen, but is available in very low amount. P deficiency in rice would reduce the number of tillers and grain production. There are numerous publications on exploration of genes that are associated with P. Many researches on P that are directed to breeding program and involving many countries/institutions focus on Pup1 research. Pup1 (P uptake 1) is associated with P uptake has been well mapped on chromosome 12 at a distance of 15.31 to 15.47 Mb and microsatellite markers between RM28073 and RM28102 can be used as a selection tool in the MAB (Marker Assisted Backrossing) program. Indonesia is very concerned with this research because of P-deficient problem. This review aims to provide current information of research that explore the genes in Pup1 locus. This review outlines the history of Pup1 mapping, to explain sequence and expression analysis of Pup1, and to inform of Pup1 specific primers. The latest information is expected to be useful for rice breeders in Indonesia, especially for those who are interested to P deficiency research. Study of genes within Pup1 locus is still ongoing, and found that some genes do not contribute directly to P uptake. This may indicate that Pup1 locus use other mechanisms in the P uptake. This may indicate that some genes (dirigent-like, fatty acid α-dioxygenase, aspartic proteinases) play a role in the increasing level of lignin in P deficient condition. Increasing level of lignin would increase the volume of roots and thus increasing P uptake and resistance to biotic and abiotic stresses. Specific markers to detect the genes in the Pup1 locus have been successfully developed, and can be used for breeding and exploration activities on Indonesian rice germplasm.