Open AccessYield responses to P fertilisation of onion (Allium cepa L.) and cabbage (Brassica oleracea Capitata Group L.) in Finland
Author(s) -
Risto Uusitalo,
Terhi SuojalaAhlfors,
Pirjo Kivijärvi,
Timo Hurme
Publication year - 2018
Publication title -
agricultural and food science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.347
H-Index - 35
eISSN - 1795-1895
pISSN - 1459-6067
DOI - 10.23986/afsci.67703
Subject(s) - brassica oleracea , loam , allium , capitata , yield (engineering) , crop , agronomy , brassica , human fertilization , biology , horticulture , toxicology , soil water , ecology , materials science , metallurgy
Finnish data on vegetable crops’ yield responses to phosphorus (P) applications are scarce, but P is usually applied in quantities that meet the crop demand with wide safety margins. We determined yield responses to P fertilisation of onion and cabbage at three sites in 3-year field trials. Only on a sandy loam with low P status did annual P applications give statistically significant yield increases, 7% and 20% over the P-unfertilised treatment for onion and cabbage, respectively. The maximum P rate allowed by national regulation for this soil is 80 kg ha-1, but P rates of 10–12 kg ha-1 were sufficient to produce 97% of the yield maxima. The results strongly suggest that the P demand of the studied vegetables is smaller than previously thought also in a boreal climate. Critical soil test P concentrations for vegetables should be established to avoid unnecessary build-up of soil P that may be uneconomical and elevate the risk for P losses to waterways. However, too few data exist for this at present.