اثرات بستر پایه و مکملهای غذایی بر شاخصهای رشدی قارچ صدفی فلوریدا (Pleurotus florida)

Abstract

Introduction: Oystermush rooms contain a wide enzymatic system to catalyze lignocellu lose and naturally live in organs of plants that are protein-rich. Agricultural and industrial wastes contain organic cellulosic materials such as cereal straw, sawdust and leaves that are suitable substrate for growth of oyster mushrooms. Previous studies have shown that dietary supplements increase growth indices of oyster mushrooms. Materials and Methods: Spawn of Florida oyster mushrooms wereprovided experimentally on grains of wheat. The experiment was conducted in the laboratory of the Agricultural College of Mehr Shar, Islamic Azad University of Karaj, Iran in 2011. Two factors were considered in this study substrate (A) and dietary supplements(B). Sugarcane bag asse (A1) and wheat straw (A2) were shed into polyethylene bags after they were pasteurized by boiling vapor and spawning was conducted according to wet weight of straw bags which was 4 kg. Supplements of Nitrogen werecottonseed powder, 2%soya flour, and urea0.5% that were added to substrate according to dry weight of substrate (1334 gr). Mushrooms were transferred to the laboratory after cropping in order to measure dry and wet weight. They were packed and dried in the oven during 24-72 hours at 60-70oC. In order to estimate the biological efficiency, the produced crop was divided by weight consumed substrate that was multiplied by 100. A completely randomized factorial statistical experiment according to completely randomized design with 16 treatments and three replications was conducted. MSTAT soft ware was used for statistical analysis and the Dunkan test was used for comparing mean data with probability of 5%.Finally figures were drown using Excel. Results and Discussion: In wheat straw substrate mushrooms were produced with high biological efficiency and yield, because compared to sugarcane bagasse, wheat straw needs a shorter period for fermentation, contains more nutrients, catalyzed faster than sugarcane bagasse soit provided mycelium with the nutrient amount of biological efficiency that increased byadding dietary supplements there for ethe yield was higher than control. Temperature of substrate increased by combining urea, cotton seed powder and soya flour nitrogen supplements, and that large amount of nitrogen were released into the environment and high temperature substrate. So expansion of mycelium decreased and mushrooms with low biological efficiency and low yield were produced. The highest biological efficiency (23.03 %) and the highest yield (4/921 gr) were obtained through wheat straw that fed by cotton seed powder + soya flour (A2B6).The lowest biological efficiency (10.48 %) and the lowest yield (419 gr) were from control treatment (A1). Frequency of nitrogen in cotton seed powder is one of the most important reasons of increasing biological efficiency and yield. Another efficiency biologic factor was used in cultivation of fungi was C/N ratio, since nitrogen is a necessary factor for the activity of ligninoletic enzyme that is produced by basidiomycets. Cultivated fungi on wheat straw were wetter than mushrooms cultivated on sugarcane bagasse, because wheat straw has 10-15%water and sugarcane bagasse has 9% moisture. Wheat straw with cotton seed + powder soya flour (A2B6) and control treatment (A1) had the highest moisture (92.26%). Byaddition of dietary supplements in the surface of enriched substrate, fruit body density had increased in control, so mushrooms were less exposed to the air flow, but the combination of nitrogen supplements, the arrival of more nitrogen andsubstrate heat increased and that the mushrooms had less humid. In wheat straw substrate more number of body fruits was obtained in comparison with sugarcane bagasse substrate..418 numbers of body fruits obtained from wheat straw by cotton seed powder + soya flour (A2B6) and 163 mushrooms were obtained from control treatment (A1). Absorbable chemical compounds in the medium were used faster and the number of mushrooms in wheat straw substrate with cotton seed powder and soya flour (A2B6) increased while combination of supplements and heat due to entrance of nitrogen caused death of mycelium and decreasing number of mushrooms. The results analysis of variance, substrate effect and mean compare supplement effect was significant at 1% on biological efficiency. Yield, moisture, number of body fruit, mean interaction effect of substrate and supplement was significant at 0.05on biological efficiency, yield and moisture but mean interaction effect of substrate and supplement on the number of body fruit was significant at 1%. Conclusion: Medium has a deep impact on growth indices of Florida oyster mushrooms in such a way that obtained mushrooms from rich mediums had higher growth indices than control. The impact of dietary supplements on growth indices is different and by adding an appropriate amount of dietary supplements to medium increases growth indices.