Sources of Potassic Fertilization in Soybean Production under Different Irrigation Blades

Abstract

Aims: The objective of this research was to evaluate the physiological and biometric parameters of the soybean crop in potassic fertilization sources under different irrigation blades. Two potassium sources (ground rock, “phonolite”, with 9% K2O and potassium chloride with 60% K2O) and five irrigation blades (30, 70, 100, 130 and 160% of the recommended blade) were used.
 Study Design: The experimental design was in randomized blocks, with ten treatments and four replications, in a 2 x 5 factorial scheme, totaling 40 vessels.
 Place and Duration of Study: Sample: Department of Agronomy, UNIFENAS, between March 2018 and November 2018.
 Methodology: Soil moisture was determined through tensiometers, using a water potential of -30kPa, considered adequate for the soybean crop. At the end of the crop cycle, the weight of shoot dry matter, weight of 1000 seeds, weight of seeds standardized to 13% moisture, total chlorophyll, chlorophyll a, chlorophyll b and carotenoids, besides nutrient content of the leaf tissue, were evaluated.
 Conclusion: KCl favors the accumulation of dry matter, weight of 1000 grains and grain production in the soybean crop in the different irrigation blades. Phonolite increases calcium and magnesium contents in the leaves, independently of the irrigation blade used, also favoring the increase in phosphorus and sulfur contents when soil moisture increases.

Efficiency of phonolite as a potassium source for Paiaguás palisadegrass

“…As observed here, other authors have reported the beneficial effect of potassium fertilization on dry weight production in U. brizantha (Orioli Júnior & Coutinho 2009, Megda & Monteiro 2010, Morais et al 2016) and that KCl is a fertilizer more efficient than phonolite (Bianchini & Marques 2019, Boldrin et al 2019. Given the low efficiency of phonolite, adding 30 % of KCl to the blend to provide the K needed for initial plant growth was insufficient to produce the same amount of dry weight obtained with the application of the water-soluble source (KCl) alone.…”

Alternative for potassic fertilization of vegetables in organic management in low fertility natural soil of the humid tropics

“…Another source of nutrient that has shown significant impact as an alternative source of K, is rock dust, also known as rockiness, a technique that positively alters soil fertility (Bianchini and Marques, 2019).…”