Incorporação do Substrato Gasto de Cogumelos de Pleurotus ostreatus nos atríbutos químicos de Luvissolo Crômico do Cariri Paraibano.

Abstract

After the mushroom cultivation process, the spent mushroom substrate (SMS) is obtained, grown in a material with a high lignocellulosic content and rich in organic matter, which, when incorporated into the soil, can change its chemical attributes. The objective of the work was to evaluate the influence of the spent mushroom substrates (SMS) of Pleurotus. ostreatus on the chemical attributes of Luvissol. The experiment was conducted under a CRD (Completely Randomized Design) with a factorial arrangement of 3 x 2 + 1 with 3 replications, using 3 lignocellulosic substrates from the main cultures of Paraíba and two conditions more an additional treatment as a control (pure soil). In this sense, the substrates of sugarcane bagasse, pineapple sprouts and corn stubble, all dosed at the same carbon level considering corn stubble as an incorporation model (8 Mg ha-1 ) were incubated in 100 g of Luvissol, collected in a degradation area, in the municipality of São João do Cariri – Paraíba, at 80% field capacity for 75 days, under laboratory conditions with 24.23 ± 0.94 ºC and 82.37 ± 8.77% relative humidity. The experimental unit consisted of a 500 mL pot with 100 g of soil mixed with lignocellulosic waste. After the soil incubation period, the levels of organic carbon (CO), labile phosphorus (P), sum of bases (SB = K+ , Na+ , Ca+2 Mg+2), base saturation (V), exchangeable acidity were analyzed (Al+3), potential acidity (H + Al), electrical conductivity (EC), pHH20, pHKCL and pHCaCl2. The results were submitted to ANOVA and Scott-Knott's test at 5% significance level (P<0.05). It was observed that in natura pineapple and corn stubble sprouts incubated in the soil showed the highest levels of CO and P with 23.87 dag kg-1 and 18.14 dag kg-1 , respectively. On the other hand, the SMS of pineapple sprouts showed the highest levels of CO with 21.44 dag kg-1 and P with 18.95 mg kg-1 . In both conditions, sugarcane bagasse showed the lowest values of electrical conductivity with 192.67 μS cm-1 (in natura) and 200,90 μS cm-1 (SMS), even lower than that observed in the control treatment (263.97 μS cm-1 ). It was conclued conclude that the spent mushroom substrate from pineapple sprouts and sugarcane bagasse increased the levels of organic carbon, assimilable phosphorus and reduced electrical conductivity.