© 2015 Somnath Roy et al. This is an open access article distributed under the terms of the Creative Commons Attribution License -NonCommercial-ShareAlike Unported License (http://creativecommons.org/licenses/by-nc-sa/3.0/ ). Journal of Applied Biology & Biotechnology Vol. 3 (03), pp. 022-027, May-June, 2015 Available online at http://www.jabonline.in DOI: 10.7324/JABB.2015.3305 ISSN: 2347-212X Evaluation of Spent Mushroom Substrate as biofertilizer for growth improvement of Capsicum annuum L. Somnath Roy, Shibu Barman, Usha Chakraborty and Bishwanath Chakraborty* Immuno Phytopathology Laboratory, Department of Botany, University of North Bengal, Siliguri- 734013, West Bengal, India. ARTICLE INFO ABSTRACT Article history: Received on: 17/01/2015 Revised on: 24/02/2015 Accepted on: 16/04/2015 Available online: 20/05/2015 Influence of spent mushroom substrate (SMS) of oyster mushroom and button mushroom on the improvement of health status of Capsicum annuum L. was investigated. Analysis of growth promotion in terms of height, no of branches, yield and no of leaf drop indicated that the use of the spent mushroom substrate of oyster mushroom and spent compost of button mushroom had a positive effect on the overall growth of the tested plants. SMS had a role in mobilizing the soil phosphate which was evident by a decrease in soil phosphate level and increase in root and leaf phosphate following treatment with SMS. Chlorophyll content of plants increased when treated with oyster mushroom fresh substrate and button mushroom leachate compost. Fruits of plants treated with button mushroom leachate compost and oyster mushroom fresh substrate showed an increase in protein content of about 2.5 times over control. Similarly, carotenoid contents of fruits also increased significantly in the treated plants, but increases in leaves were not significant. It is evident from the present study that the use of different form of spent mushroom substrate of oyster mushroom and spent compost of button mushroom led to the overall increase in growth of Capsicum annuum L. Key words: Capsicum annum, Chlorophyll, Plant growth, Spent Mushroom Substrate. 1. INTRODUCTION After mushroom cultivation, the partially degraded paddy or wheat straw and other agricultural waste, which form as valuable by-products of edible mushroom cultivation, have been termed as Spent Mushroom Substrate (SMS). This SMS, which contains simpler form of protein rich component formed by modification of agricultural materials by the fungus after few cycles of cultivation, can be used as very good soil conditioners for the cultivation of fruits, vegetables flower and foliage crops [1]. Spent mushroom substrate is a good source of carbon, nitrogen and other elements. Nitrogen content varies from 0.4- 13.7% with a C: N ratio of 9 to 15: 1 [2] which enhances the growth of plants. The mushroom production is increasing day by day and about 10 million metric tons of spent mushroom compost, a by-product of Agaricus bisporus is produced per year [3, 4]. After the mushroom harvest, the substrates have to be removed as storage of this spent substrate may cause environmental contamination. Using the spent mushroom compost as organic manure is one of the solutions to utilize the spent compost in a better way. The rich organic matter, moderate nutrient load, near neutral pH and presence of beneficial microbial population make SMC as a suitable organic waste for its conversion into quality manure for crops. It has been observed that the SMS has potential to bioremediate several agricultural grade fungicides and pesticides [5, 6, 7]. * Corresponding Author Email: bncnbu [at] gmail.com After suitable pre-treatment, spent mushroom substrate can completely or partially substitute the growing media for cultivation of different economically important horticultural crops [8, 9]. There are several methods of using the spent mushroom compost and weathering is one of them. Spent substrates can be spread on the land and allowed to weather for one or more years which allow to reduce the salt and nitrate contents of the spent materials. However, weathering alone is not sufficient and leaching is a better method for reducing salinity of the spent mushroom substrate. Leached spent compost has been reported to have less salinity than the weathered compost and most of the essential elements as well as the microbial properties remain the same as normal spent compost [10, 11, 12]. Thus spent mushroom substrate is considered to be a good source of organic matter and rich in macro and micro elements for plants, which help to increase the soil biological activity [13, 14]. It is also known that roots of most plant supports a wide range of fungal communities which colonize roots intra and intercellularly. Such fungi are known as arbuscular mycorrhizal fungi (AMF) [15]; besides, ectomycorrhizal and ectotrophic associations between fungi and plants [16] are also common. Another group of fungi which are commonly found in soil help in growth promotion upon root colonization are known as plant growth promoting fungi (PGPF) [17]. These are beneficial to several crop plants in respective of growth promotion as well as disease suppression [18]. The present study has been undertaken to evaluate the effect of spent mushroom substrate of different edible mushroom as biofertilizer on the growth and biochemical changes of Capsicum annuum L.