UTILIZATION OF LIGNOCELULOSIC MATERIALS AS SUBSTRATE FOR Pleurotus ostreatus CULTIVATION. CHIRIQUI, PANAMA. 2003.

Abstract

The biological efficiency of a Pleurotus ostreatus strain (RN 8) was studied on rice straw (Oriza sativa), coffee pulp (Coffea arabica) and banana leaves (Musa sapiensis) in terms of the percentage relationship between the fresh mushrooms weight and the dry substrate weight. The relationship between the biological efficiency and the chemical composition of the substrates (ash, nitrogen, cellulose and lignin contents) was also studied. The data was analyzed by means of a hierarchic model, random sampling techniques and both regression and correlation analyses. Variance analysis showed highly significant differences in the biological efficiency between the substrates (P<0.01). The highest biological efficiency was obtained in rice straw (80.32 ± 4.90), followed by coffee pulp (63.13% ± 4.90) and banana leaves (49.43% ± 4.51) with significant differences (P<0.05) between coffee pulp and the other two substrates but not between coffee pulp and banana leaves. In banana leaves the biological efficiency was positively correlated to the nitrogen and lignin contents (r= 0.21409 and 0.01733, respectively) and negatively correlated to the ash and cellulose contents (-0.17722 and -0.08922, respectively). In rice straw, biological the biological efficiency was positively correlated to the ash and cellulose contents (r= 0.29794 and 0.12837, respectively) and negatively correlated to the nitrogen and lignin contents (r= -0.24152 and -0.11653, respectively). In coffee pulp, the biological efficiency was positively correlated to the nitrogen, lignin and cellulose contents (r= 0.46476, 0.33370 and 0.14300, respectively) but negatively correlated to the ash content (r=-0.47491). The only statistically significant associations were those between the biological efficiency and the ash and nitrogen contents in coffee pulp (r= 0.0092; P<0.01 y r= 0.0167; P<0.05). A linear model with zero intercept was the best in describing the variation between the biological efficiency and the chemical composition in banana leaves (R²=0.9234, 0.9311, 0.9191, 0.9213 for ash, nitrogen, lignin and cellulose respectively); for ash, cellulose and nitrogen in rice straw rice (R²= 0.9014, 0.8935 and 0.8852, respectively) and for nitrogen, lignin and cellulose in coffee pulp (R²= 0.9654, 0.9641 and 0.9588, respectively). A quadratic model was the best for lignin in rice straw (R²= 0.8901) and for ash in coffee pulp (R² =0.9659). The variation of the biological efficiency in terms of the substrates is demonstrated. A controlled multiple factorization analysis is recommended.