Coffee seedling growthafter legume cultivation in soils with contrasting phosphorus contents

Abstract

Coffee seedling growth depends on soil phosphorus (P) availability and may be influenced by from pre-cultivation with legumes. Efficient and sustainable ways to increase the bioavailability of P through the recovery of P adsorbed by the soil matrix should be sought. This study proposed to evaluate the growth and P-use efficiency of coffee seedlings cultivated in soils with different P availability after cultivation with legumes. The experiment was carried out in a fully randomized design. Treatments were arranged in a factorial scheme [(2 x 4) + 1]: two soil types, pre-cultivation with four legume species, and one control (withoutpre-cultivation). The studied soils comprised a Typical Acriferic Red Oxisol (LVwf) with low-P availability and a Typical Chernossolic Litholytic Entisol (RLm) with high-P availability. The legume species Crotalaria juncea, Cajanus cajan, Canavalia ensiformis, and Mucuna aterrima were previously cultivated for 45 days. Afterwards, coffee seedlings were transplanted to the pots, which were then grown for 120 days until evaluations. We assessed the following parameters: plant height (H), stem diameter (SD), shoot dry matter (SDM), root dry matter (RDM), total dry matter (TDM), and shoot contents of macronutrients. Our results showed that coffee seedlings grew more when cultivated in the high-P availability soil, with increments of 13.05% in H, 4.86% in SD, 46.98% in SDM, 17.61% in RDM, and 41.80% in TDM.We also observed an increase of 28.09% in shoot P contents for coffee seedlings grown in RLm. Moreover, pre-cultivationwith C. juncea provided the largest increases in coffee seedling growth compared to the control. When grown after C. ensiformis cultivation, coffee seedlings had the highest shoot contents of P, Ca, Mg, and S, which, compared to control, increased by 45%, 39%, 18%, and 17%, respectively. Keywords: Canavalia ensiformis; Crotalaria juncea; Coffea arabica; phosphate fertilization; nutritional efficiency.