Transgenic Cotton Allows Selective Fertilization for Weed Control

Weeds, which have long been a problem in agriculture, are managed manually, mechanically, as well as by using chemicals. However, chemical control options are dwindling due to the rise of herbicide-resistant weeds in fields. Devendra Pandeya and Damar L. López-Arredondo from Texas A&M University and StelaGenomics México, respectively, led a team of researchers to develop an alternative weed control system.

Their team developed transgenic cotton (Gossypium hirsutum) plants expressing the bacterial phosphite dehydrogenase (ptxD) gene, which confers the ability to convert phosphite (Phi) into orthophosphate (Pi), the metabolizable form of phosphorus (P). When P is supplied in the form of Phi, the ptxD-expressing cotton plants outcompete different weed species intentionally introduced in the experiments, as well as weeds naturally present in the tested soils. Furthermore, the ptxD/Phi system was highly effective in inhibiting the growth of the glyphosate-resistant Palmer amaranth.

With several weed species having resistance to currently available herbicides, these ptxD-transgenic plants fertilized with Phi presents an effective alternative for suppressing weed growth.

For more information, read the full article in Proceedings of the National Academy of Sciences of the United States of America.