Stabilising Urea Amine Nitrogen Increases Potato Tuber Yield by Increasing Chlorophyll Content, Reducing Shoot Growth Rate and Increasing Biomass Partitioning to Roots and Tubers

Abstract

Much of the nitrogen in crop fertiliser is degraded before acquisition. Technologies that stabilise urea-nitrogen minimise this. Degradation also specifically reduces the amount of ureic amine that many fertilisers initially contain, which is important because this nitrogen form has unique beneficial effects on plants. To investigate mechanisms whereby urea stabilisation increases potato tuber yield, we compare effects of foliar applications of chemically stabilised and non-stabilised urea against industry-standard fertiliser, on the physiology, form and yield of greenhouse-grown Casablanca under identical nitrogen supply. Stabilised urea is tested on Rooster and Shelford yields in Irish and British field trials. Stabilised amine nitrogen (SAN) increases Casablanca leaf relative chlorophyll content and initially reduces shoot growth rate. When harvested shortly after tuber initiation, SAN-treated plants have increased root to shoot weight ratios and we find tight negative correlations between shoot growth rate and root weight: large roots and slow shoot extension occur predominantly in SAN-treated plants. SAN increases ratios between initiation-stage tuber weight and (a) shoot length and (b) shoot growth rate. At a second harvest at mid-bulking, SAN increases highgrade Casablanca tuber yielding. At this later stage, yield correlates positively with shoot weight. In the field, SAN increases Rooster canopy greenness and marketable yields of both Rooster and Shelford. Yield improvements specific to this N form when stabilised are suggested to occur through increased photosynthesis and early-stage increases in root to shoot weight ratio. This phenotype then supports increased bulking-stage shoot growth and shoot-sourced resource for tuber growth. Stabilising urea amine induces high-yielding phenotypes with improved internal nitrogen utilisation efficiencies.

The Impact of Fertilization Regime on the Crop Performance and Chemical Composition of Potato (Solanum tuberosum L.) Cultivated in Central Greece

“…Mirdad [42], who carried out a field study comparing the impact of organic (chicken manure) and mineral fertilizers on tuber yield of two potato cultivars (Nicola and Diamond), reported significant differences in tuber yield between the tested cultivars, although both of them showed the highest yield when moderate levels of organic (15 tons/ha) and mineral fertilization (300-150-150 kg/ha of N-P-K) were applied. Moreover, according to Wilkinson et al [43] the use of fertilizers containing stabilized urea-nitrogen may increase tuber yield through the increased plant growth and nitrogen use efficiency compared to non-stabilized and conventional fertilizers. Dry matter contents (%) of leaves, shoots and tubers are presented in Table 2.…”

Methylglyoxal improves zirconium stress tolerance in Raphanus sativus seedling shoots by restricting zirconium uptake, reducing oxidative damage, and upregulating glyoxalase I

“…We suspected a direct link between biomass improvement and chlorophyll maintenance in response to MG and Zr. Wilkinson et al 30 have shown previously that a correlation exists between chlorophyll content and biomass in plants. In our study, we observed an increase in chlorophyll a and total chlorophylls in response to MG treatment.…”

Use of GreenSeeker and CM-100 as manual tools for nitrogen management and yield prediction in irrigated potato (Solanum tuberosum) production

“…However, the yield prediction at the vegetative stage using any of these sensors might be reliable than the late growth stages of the crop. Early research found a highly significant correlation coefficient between tuber yield and leaf chlorophyll content values measured with SPAD (Majić et al, 2008;Güler, 2009;Wilkinson et al, 2019). A significant correlation was also reported between NDVI values and the yield of grain crops (Lofton et al, 2012;Cao et al, 2015;Zaeen, 2020).…”