02412naa a2200253 a 450000100080000000500110000800800410001910000130006024501060007326000090017952016510018865000210183965000270186065000300188765000280191770000190194570000170196470000180198170000230199970000180202270000230204070000170206377300780208011345592024-05-28       2024    bl uuuu     u00u1 u    #d1 aHAHN, L.  aPotassium Reference Values in Garlic Cultivars Grown in a Subtropical Climate.h[electronic resource]  c2024  aIntroduction Potassium management is crucial for high-yielding garlic (Allium sativum) production, but knowledge on critical levels (CL), sufficiency ranges, and optimal fertilizer rates is limited. Purpose The study aimed to establish cultivar-specific CL values for soil and leaf K, as well as maximum technical efficiency (MTE) and economic efficiency (MEE) potassium, and fertilizers application rates, to optimize marketable garlic bulb yield in a subtropical climate. Methods The study was conducted in three municipalities of Santa Catarina, southern Brazil, on clayey soils. Garlic cultivars ?Chonan?, ?Ito?, and ?Roxo Caxiense? were subjected to four K rates, and a control without fertilization (0, 50, 100, 250, and 500 kg ha-1 K2O). Total, marketable, and non-marketable yields, bulb diameter classes, soil K availability, and total leaf K concentration were assessed in 20 field trials in the 2015 and 2016 crops. Results The CL of K established in the soil were 335, 320, and 345 mg dm-3 K, and in leaves 26.5, 26.5, and 24.7 g kg-1 K, for the respective cultivars. The MTE and MEE of K fertilizer application rates for marketable garlic yield were 334 and 320 kg ha-1 K2O. Additionally, a K buffering capacity (KBC) of 2.3 was established, indicating the K2O rate (kg ha-1) needed to raise Mehlich-1 extractable K by 1 mg dm-3. Conclusions Our findings can help garlic growers improve the K nutritional management to obtain high yields and reduce fertilizer costs. Furthermore, the establishment of cultivar-specific K reference values adds valuable information to the limited data available on K nutrition in subtropical climates.  aGarlic nutrition  aNutritional references  aPotassium buffer capacity  aPotassium fertilization1 aFELTRIM, A. L.1 aENDER, M. M.1 aGRANDO, D. L.1 aMOURA-BUENO, J. M.1 aTASSINARI, A.1 aLIMA-RODRIGUES, M.1 aBRUNETTO, G.  tJournal of Soil Science and Plant Nutrition, Chilegv. 24, p. 1-10, 2024.