Capacidade produtiva e biodegradativa de cogumelos do gênero pleurotus cultivados em resíduos lignocelulósicos

Abstract

Edible mushrooms of the genus Pleurotus are selective white rot organisms that efficiently degrade lignocellulosic compounds through their rich and diverse enzymatic cocktail, which allows the use of agro-industrial wastes for the cultivation of these species. This research aims to evaluate the influence of different proportions of sugarcane bagasse and banana leaf on productive and biodegradative parameters of P. djamor and P. ostreatus grown in solid state fermentation. The experiment was carried out under a CRD of 5 treatments and 8 repetitions, which were constituted in the proportions 0%, 25%, 50%, 75%, 100% of sugarcane bagasse complemented in percentage with banana leaves (%, m/m), and supplemented with 10 g of wheat flour and 10 g of sawdust. The formulations were moistened at 68% (v/m), placed in 15 cm × 30 cm × 6 mm polypropylene bags and sterelized for one hour at 120° C and 103 kPa. The inoculation was performed with 40 g of inoculum of P. djamor (PDJ/R2 strain) and P. ostreatus (PO/A02 strain) per kilogram of sterilized substrate. Incubation was maintained under total darkness at 23.95 ± 0.21°C and relative humidity of 94.24 ± 3.85%, for 26 ± 6 days. For fruiting induction, 5 cm vertical cuts were made on the surface of the bags in the fruiting room, kept at a temperature of 23.85 ± 1.56°C and relative humidity of 91.20 ± 3.68%. The productive period ended with 3 harvest flows. The productive variables were evaluated: mycelial growth (cm day-1 ), precocity (days), biological efficiency (%), productive period (days), daily productive capacity (kg day-1 ) and production rate (% day-1 ), and biodegradable: loss of organic matter (%) and percentage variation in the composition of lignocellulosic material (%). The results were submitted to the Shapiro-Wilk and Bartlett tests at 5% significance level (P≥0.05) and analyzed by Tukey's test, with the exception of the cellulose percentage variation, and hemicellulose that were analyzed with the Kruskal-Wallis test, both tests at 5% significance (P<0.05). The results indicate that the 25BG treatment provides better conditions for the development of P. djamor, providing greater mycelial growth in the substrate (0.27 cm day-1 ), inducing its shorter precocity and stimulating in more than 50% the lignin biodegradation. The cultivation of P. ostreatus does not depend on the substrates under study, presents 95% of biological efficiency. P. djamor is related to the biodegradative aspects and P. ostreatus to the productive aspects when cultivated in sugarcane bagasse and banana leaves formulations. It is concluded that the cultivation of edible mushrooms of the genus Pleurotus is a viable and promising alternative for the reuse of lignocellulosic residues available in the region of Brejo Paraibano.