Effect of drought and mono-potassium phosphate (MKP) on some physiological attributes and macronutrient translocation in potato crop

Nutrient uptake and physiology of potato plants in response to monopotassium-phosphate (MKP:0-52-34) and drought was investigated in the current study.
Three different irrigation regimes were applied: 100, 75 and 50% of crop evapotranspiration (ETc). MKP was added twice at 14 and 28 days after emergence with a dose of 3 g plant^‑1. Plants irrigated by a water volume representing 100% of ETc with no MKP application were considered as control.
As a result, increasing drought stress limited some of the macro nutrient uptake and decreased chlorophyll a, b and total chlorophyll content at 75 and 50% Etc.
MKP application reduced total chlorophyll content by 12.95, 17.12 and 8.75 mg mL^‑1 at 100%, 75 and 50% of ETc, respectively.
On the other hand, MKP increased P and K content by approximately 1-2 mg g^‑1 in tubers, by 1-6 mg g^‑1 in stems and by 0.5-6 mg g^‑1 in leaves depending on the irrigation regime.
Surprisingly, Mg was decreased significantly in all parts of MKP-treated plants compared to non-treated ones except in tubers.
K/Mg ratio was increased at all irrigation regimes except in tubers following MKP application compared to non-treated plants.
MKP seems to have a counteractive effect to Mg which is an essential element in the chlorophyll molecule.
This counteractive effect caused a reduction in chlorophyll a, b and total chlorophyll content in the plants.

IV International Symposium on Horticulture in Europe – SHE2021

Y.N. Sassine, R. Bejjani, E. Tabet, A.M.R. Abdel-mawgoud, M.H. Yordanova, S.M. Alturki

Solanum tuberosum, water shortage, nutrient competition, physiology, growth

https://doi.org/10.17660/ActaHortic.2021.1327.24