A Preliminary Investigation on Potential Use of Cinnamon Outer Corky Layer as a Substrate for Pleurotus ostreatus (Oyster Mushroom) Cultivation.

Abstract

Agricultural wastes are used as a substrate to prepare media for the mushroom cultivation. Sawdust is popular among mushroom growers as a medium for cultivating mushrooms. However, the low availability of sawdust has become a severe problem at present particularly in Southern, Sri Lanka. This situation has pressurized to search for alternative media for mushroom cultivation. The corky layer of cinnamon ( cinnamon scrapings) is the byproduct remaining after scraping of cinnamon stems before extracting the peel (phloem tissue of cinnamon stems). These cinnamon scrapings are readily available throughout the Southern region. In this study, the potential of cinnamon scrapings as a substrate for the cultivation of Pleurotus ostreatus (oyster mushroom) was investigated. Nine treatments were prepared using one-week old sawdust (control), one week, two weeks, one month and two months old cinnamon scrapings either alone or mixed with sawdust at 1:1 ratio (on the dry weight basis). All the other ingredients (i.e. rice bran, green gram flour, Ca(Q3, and MgSQ4) were added to the control as well as to all the treatments in normal proportions which are being used in the preparation of standard media and were mixed well while adding required amount of water. Then prepared media was filled into mushroom bags (850±10g), sterilized and inoculated with approximately Sg of seeds (spawns). Mycelium growth in weekly (cm), total colonization time (days), the time taken for primordial formation in the first time (days), number of fruiting bodies developed at first flush, fresh weight of the yield per harvest (g) were recorded. All treatments in the experiments were arranged in a Completely Randomized Design (CRD) with twenty replicates in the mushroom house. Statistical analysis was carried out using Duncan's multiple range test using SAS software (version 9.1.3). The results showed that total colonization time (17.8±1.49 days), time taken for primordial formation in first time (22.80±1.49 days), number of fruiting body development at first flush ( 4.80±1.66), fresh weight of the yield of first harvest (65.0±8.00g), fresh weight of the yield of second harvest (25.5±9.32g), fresh weight of the yield of third harvest (20.0±9.17g) were observed only in the sawdust substrate. Mycelial growth (mean of 6.2±0.Scm) was observed in the medium of 50% sawdust and 50% two months old scrapings of a cinnamon outer corky layer only after four weeks of incubation; however, further growth of mycelium was not observed. According to the results, it can be concluded that scraping of the cinnamon outer corky layer along or mixed with sawdust at the ratio of 1: 1 cannot be used as a substrate for the oyster mushroom cultivation. Further research on understanding of chemical inhibitors that may be suppressing mycelial growth and possible pre­treatments would help to exploit the potential of the cinnamon outer corky layer as an alternative substrate for mushroom cultivation.