1.3.5.5 agriculture the Thr304 Hydrilla pds mutant is an excellent marker for the selection of transgenic plants. Seedlings harbouring Thr304 pds have a maximum resistance to sensitivity (R/S) ratio of 57 and 14 times higher than that of the wild-type for treatments with norflurazon and fluridone, respectively. These plants exhibit normal growth and development, even after long-term exposure to herbicide. As Thr304 pds is of plant origin, it could become more acceptable than other selectable markers for use in genetically modified food 1.3.5.5 agriculture fruit treated with 5-chloro-3-methyl-4-nitro-1H-pyrazole appear more yellow and/or orange than ethephon or control fruit at any harvest date 1.3.5.5 agriculture phytoene desaturase is a prominent target of certain inhibitors, such as norflurazon, acting as bleaching herbicides 1.3.5.5 synthesis the norflurazon-resistant phytoene desaturase gene is used for successful nuclear transformation and genetic engineering of the carotenoid biosynthesis pathway for accelerated astaxanthin biosynthesis (astaxanthin as a food supplement for humans) 1.3.5.5 synthesis Dunalielle salina can be used as a cell factory for phytoene production