A dataset on the preference for different nitrogen species by commercial cotton

In this project, we tested the ability of Gossypium hirstutum L. (commercial cotton) to take up different low molecular weight nitrogenous compounds (nitrate, ammonium, urea, alanine).

Three varieties of G. hirsutum were grown to a two- to four-leaf stage in a randomised block design with 10 replicates. The three varieties used were: Sicot 746B3F, a genetically-modified (GM) current commercial cultivar accounting for more than half (54%) of the 2017-18 Australian summer plantings; Sicala V2, an obsolete non-GM commercial cultivar released in 1994; and Tx III, a Guatemalan landrace accession that represents the native origins of the commercial G. hirsutum varieties. Plants were grown in 300 mm deep low-density polyethylene (LDPE) pots, consistent with the rhizotube design used by Hill and Jones (2018). Tubes were open-bottomed, allowing drainage and preventing waterlogging. Pasteurised and washed sand of <1 mm particle size was used as the growing medium to enable control over plant-available nitrogen (N) pools and to limit the potential of microbial competition for the applied N compounds. Plants were watered using a nutrient solution mixture that constituted 100% of the plants’ soil-derived nutrient supply. The plants were grown in glasshouses at the CSIRO Black Mountain site in Canberra, ACT, Australia (35°16’S 149°7’E) in January (summer) 2018. The high solar radiation experienced by Canberra in summer required the use of 70% shade cloth, as sand temperatures exceeded 60°C when exposed to direct sunlight. In total, 450 seedlings were analysed, comprising 10 replicates each of 45 unique treatments: five isotopically-labelled N and control treatments, three G. hirsutum varieties, and four sampling times (0, 5, 60 and 180 minutes).

Latimer, J.O.; Farrell, M.; Macdonald, B.C.T. (2025) Nitrogen uptake preference of Gossypium hirsutum L. from a mixture of urea, alanine, nitrate, and ammonium. PLoS One.