**2. Mushroom production**

*Elements of Bioeconomy*

or the other. Due to land tenure system, poverty, lack of incentives, etc., more than 70% of farmers in Nigeria and other developing nations of the world are considered small-scale farmers (land holding of less than 10 ha) [2]. Continuous cultivation of the land has also led to depletion in the nutrient status of the soil. Unfortunately, cost of soil amendments such as mineral fertilizer is gradually getting beyond the reach of average farmer. Hence, if urgent steps are not taken to address the downward trend, developing world will soon be faced with food crises of unimaginable magnitude.

One of the ways of mitigating against this is the step already being experimented by the Nigerian government whereby incentives are provided to encourage women, unemployed youth and other stakeholders to get actively involved in agriculture. This is a right step in the right direction, if pursued to a logical end. However, there must be a holistic approach towards solving this problem. Such approach must include alternative source of input (fertilizer, etc.) that is affordable. It will also be necessary to find a way of forming the farmers into clusters so that processing facilities will be acquired and maximized. The government also must look into the area of packaging and transportation of agricultural produce so as to minimize loss. In a recent survey conducted in selected fruits and vegetable market in Oyo State, Nigeria, the traders complained of losing at least 5% of the purchased products between the farm gate and market due to the way the produce are stacked together during transportation and bad road network. Due to the perishable nature of these produce, a large percentage of the produce will also go into waste. If the traders must break even, they will have no other choice than to increase the price of the remaining items. Hence, buyers will be forced to pay not only for the items bought but also for the spoilt ones. The spoilt ones are usually stacked in designated places within the market community where they serve as breeding ground for disease vectors (**Figure 1**). When it rains, leachates from these dumping grounds are either washed to adjourning streams and rivers where they serve as contaminants to the water bodies or leached down the soil via deep percolation where they serve as contaminants to groundwater. Creating farm clusters will definitely boost agricultural production and encourage siting of medium- to large-scale processing plants that will add value to agricultural produce, thus enhancing the profitability of their products. It will

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**Figure 1.**

*Some horticultural waste from Odo-Oba, near Ogbomosho in Oyo State, Nigeria, West Africa.*

Across the globe, wastes are being generated from agriculture, industries, etc. To combat food security, efforts are being made to increase agricultural productivity and economic yield with little or no attention given to its disposal. When wastes are poorly managed or disposed, it may result in outbreak of disease and untidy environment, characterized with offensive odors, resulting into increase in the population of rodents and insects that could constitute threat to lives and properties. Over time, what has been considered as wastes in some enterprises, especially in agro industries, is found to be useful, thereby adding value to the supposed wastes.

Mushrooms are a group of fungi and are distinct from green plants because they lack chlorophyll and therefore cannot manufacture their own food as other plants do but rather produce extracellular enzyme which digest various kinds of dead organic matter on which they grow [8]. It contains all the essential amino acids (for humans) as well as most commonly occurring non-essential amino acids and amines. These include phenylalanine, valine, theanine, tryptophan, isoleucine, methionine and leucine [9, 10].

Mushrooms are a good source of protein that can enrich human diets, especially in some developing countries where meat may be rare or expensive. Many mushrooms are considered to be healthy food because they contain large amounts of qualitatively good protein, vitamins (B1, B2, B3, C and D) and minerals (potassium and phosphorus) in addition to folic acid, an ingredient known for enriching the blood stream and preventing deficiencies. They have a low fat content ranging from 0.6 to 3.15%. The protein content ranges between 19 and 37%, depending on the

variety [11, 12]. They are conventionally grown on agro-industrial wastes containing lignin, cellulose and hemicelluloses. In Nigeria and other parts of the world, tons of these wastes are generated annually which, if not managed, will constitute a menace to the environment. Different agro-industrial wastes singly and in combination have been used for the cultivation of different mushrooms such as *Volvariella volvacea*, *Pleurotus* species, *Agaricus* species, etc*.* [13–15]. The waste used in mushroom production includes banana leaves, water hyacinth, sawdust, rice straw, maize stover, corn cob, cassava peels, grass straws, oil palm processing wastes, etc.

The first step in mushroom growing is the choice of which mushroom species to grow. The culture of the choice mushroom can be obtained and prepared into the planting spawn, or the spawn is purchased directly from a mushroom laboratory. The second step is sourcing for a readily available substrate within the grower's immediate environment to cut down production cost. This step is followed by the preparation of the growing medium or substrate which may include chopping, breaking, soaking or moistening, depending on the type of substrate. They can be used fresh (rice straw, maize cob, banana leaves, etc.) or composted (sawdust). Some (straws, vines and wood) may require chopping into smaller sizes of 3–5 cm, while others can be used directly (e.g. sawdust) [16]. It is also required that the growth materials are disinfected to rid them of other inherent micro-organisms and insects by applying heat or chemical treatments [17, 18]. The third step in mushroom growing process is the transfer of the spawn or inoculum (planting material) to the growth medium after disinfection. This is done using a standard method in a laminar flow chamber or a locally fabricated inoculation hood, to avoid contamination of the disinfected substrate by unwanted micro-organisms. After inoculation or planting, the substrates are then moved to a dark room or incubation chamber and left for a period depending on the mushroom species that is being grown; it is a time during which the mushroom mycelium ramifies the entire substrate. After incubation, the substrates are subjected to a fruiting condition where the mushroom fruiting body initials or primordia begin to appear and are harvested after maturity. Mushroom cultivation processes are presented in **Figure 2**.

#### **Figure 2.**

*Mushroom cultivation processes. (a)–(g) represent substrate preparation, mixing and bagging, actively growing mushroom planting material (spawn), inoculation/spawning of substrate bags, Volvariella volvacea growing on banana leaves, and Calocybe indica (milky mushroom) growing on sawdust substrate and freshly harvested mushrooms, respectively.*

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space (**Figure 3**).

*The Use of Waste Management Techniques to Enhance Household Income and Reduce Urban…*

Mushrooms are a high-value niche product; its production is a viable source of livelihood and food security. Cost–benefit analysis of different aspects of mushroom production was investigated by [19]. The authors reported a cost–benefit ratio of 2.30, 3.13 and 1.8 on mushroom spawn production, substrate preparation and mushroom fruiting body production, respectively. Celik and Peker [20] and Basanta et al. [21] also reported the profitability of mushroom fruiting body production in

Compost fertilizers are organic fertilizers made from plant and animal leftover that have been decomposed by the existing micro-organism [22, 23]. The main objective of making compost manure is to recycle these nutrients in plants and animal leftover back to the soil for plant growth. The practice improves the soil physical, chemical and biological activities, improving crop yields and nutritional values. It also maximizes the use of available organic resources on the farm and minimizes the use of costly inorganic agrochemicals [24, 25]. Process involved in making compost is referred to as composting. Composting is defined as a biological process in which a micro-organism converts organic materials such as manure, sludge, leaves, peels, animal waste and food waste into a soil-like material called compost in the presence of water and air [26]. It is the main process used to produce stable, high-quality organic fertilizers from organic waste [27]. Composting is done to transform and stabilize organic materials into stable, usable products, to produce uniform organic fertilizer suitable for soil amendment and to remove offensive odors, to kill weed seeds and pathogenic organisms [28]. Compost can be made from crop residues, husks, stovers and agricultural, domestic and industrial wastes that are accessible and available, combined with animal manures. Human wastes can also be composted for crop production, but it is not encouraged due to disease

Nigeria is the leading producer of cassava in the world, producing 37 million tons/year on 2.5 million hectares of land [30]. Accompanied with this output is the large volume of cassava peels being released as waste by processing centres all over Nigeria. It is usually burnt or used to feed livestock (most especially small ruminants) as source of protein and roughages. However, not more than 10% of the cassava peels produced is utilized in feeding livestock. The remaining is commonly found in farm and other processing sites as heap that are generally perceived as a nuisance [28]. These materials, however, could be utilized more effectively and sustainably through recycling rather than being destroyed through burning as commonly practiced by many leading to air pollution. Wastes such as cassava peels are rich in crude protein (5.29%) and fat (1.18%) [31]. Utilization of the peels and other agricultural wastes is limited by its low digestibility. Composting will not only reduce toxicity but also convert the resistant lignocellulose material into a more digestible substrate. Preparing compost from wastes offers many advantages. It provides incentive for communities to recover locked nutrients in the wastes, eliminate the problem of waste disposal and increase the manurial values of the materials [32]. Compost can be prepared throughout the year. Three common methods of preparing composts include on the earth/flat surfaces, the use of compost pits and preparation in boxes. Methods adopted are dependent on availability and access to

Compost manure will regulate soil structure, softens hard soil and improves the water holding capacity of the sandy soil, thus increasing soil aeration and the soil's ability to withstand erosion by wind or water [25]. It requires little or no technical

*DOI: http://dx.doi.org/10.5772/intechopen.85580*

Bulgaria and Bangladesh, respectively.

and pathogen transmission [29].

**3. Composting**

*The Use of Waste Management Techniques to Enhance Household Income and Reduce Urban… DOI: http://dx.doi.org/10.5772/intechopen.85580*

Mushrooms are a high-value niche product; its production is a viable source of livelihood and food security. Cost–benefit analysis of different aspects of mushroom production was investigated by [19]. The authors reported a cost–benefit ratio of 2.30, 3.13 and 1.8 on mushroom spawn production, substrate preparation and mushroom fruiting body production, respectively. Celik and Peker [20] and Basanta et al. [21] also reported the profitability of mushroom fruiting body production in Bulgaria and Bangladesh, respectively.
