Volume 6, Issue 6, December Issue - 2018, Pages:903-911
|Authors: Sakharam Kale, Prerna Nath, VS Meena, Devender Kumar, RK Singh|
|Abstract: An innovative polyhouse was developed for production of button mushrooms in hot region of Punjab. Length, width and ridge height of polyhouse was 15, 4 and 4.27 m, respectively. Floor was kept at 1 m below ground level. Roof was thermally insulated whereas walls were ventilated. Heat load analysis of polyhouse was carried out in the study. Polyhouse was equipped with fan-pad system and foggers to attain cooling through evaporative cooling mechanism. Water required to reduce the inside temperature by 10°C was determined as 1.3 liters. Performance of polyhouse was evaluated in terms of attaining the desirable temperature and humidity conditions. Results indicated that on operating the cooling systems, inside temperature and RH during October were 22-27°C and ≥75%, respectively. These conditions were suitable for spawn run. In November polyhouse provided 20-22°C temperature and ≥75% RH. These conditions were suitable for case run and fruiting. Favorable temperatures and RH were achieved during February and March also. Thus, study demonstrated that, in hot region, button mushroom farming may be started in October month and can be carried out till March using polyhouse developed in study.|
|Full Text: 1 Introduction Button mushrooms (Agaricus bisporus) are the fruiting bodies of fungus containing proteins, vitamins, fibers and minerals (Kaur & Rampal, 2017). Protein content of button mushrooms varies from 20 to 35% (d.b.) which is higher than many fruits and vegetables (Thakur, 2014). Commercially produced button mushrooms contain 90% moisture content (w.b.), 3% proteins (w.b.), 5% carbohydrates (w.b.), 1% fats (w.b.) and 1% minerals and vitamins. Consequently, they are the crucial food items concerning human health, nutrition and disease prevention (Chang, 1996). Moreover, mushrooms are acknowledged by FAO as food contributing to protein nutrient in diet of developing countries where most of the population is heavily dependent on cereal/starchy diets (Karthick & Hamsalakshmi, 2017). On considering the health importance of button mushrooms, their farming was started in India during 1960s in temperate region due to availability of favorable climate in region. Huge amount of agricultural wastes in the form of wheat and paddy straw, availability of suitable strains and farming techniques contributed to growth and diversification of mushrooms in the country (Maheshwari, 2013). Presently, total mushroom production of the country is 4,59,000 MT (Anonymous, 2017). The leading mushroom species produced in the country include button, oyster and paddy straw mushrooms. However, button mushrooms alone contribute almost 90% of total mushroom production of the country (Mehta et al., 2011). Literature reveals that yield and quality of button mushrooms predominantly depends on environment inside mushroom house. Indeed, button mushrooms are very sensitive to environmental factors (Van Peer et al., 2009). Major environmental factors affecting button mushroom yield and quality are temperature, relative humidity (RH), oxygen and carbon dioxide (CO2) concentration (Schmidt, 1983; Stamets, 1993; AMGA, 2004; Sarker et al., 2008). Attainment of desirable environment in mushroom house is very crucial. For button mushroom farming, recommended temperature is 22-26°C during spawn run, 18-22°C during case run and 14-18°C during fruiting. Recommended RH during spawn and case run is 80-90% and during fruiting it should be 85-95%. Concentration of CO2 plays a vital role during spawn run. It is recommended that CO2concentration should be maintained at>1500 ppm during spawn run. However, it should to be maintained between 800-1000ppm during fruiting period of mushroom (http://agridaksh.iasri.res.in). Mushroom house provides the major interface between crop environment and ambient environment. It requires suitable arrangements to create desirable microclimate. Number of different small scale and commercial mushroom houses has been developed by various researchers (Kwon et al., 2004; Mabveni, 2004; Reyes et al., 2004; Dhar & Arumuganathan, 2005; Arumuganathan et al., 2010; Schiau, 2013). Variety of square, rectangular, curved, polyethylene covered tunnels with a range of cross-sections and shapes have been studied (Han et al., 2009; Schiau, 2013). However, in India, most of the mushroom farmers still grow button mushrooms in very temporary structures made of locally available materials. These structures lack heating, ventilation and air-conditioning (HVAC) facilities and unable to isolate mushroom environment from atmospheric environment. Some farmers constructed permanent structures with HVAC arrangements. These structures provide all essential requirements to crop but are costly and involve considerable cost of cooling and ventilation. Under such circumstances polyhouse technology, having intermediate cost, adequate life span (10-15 years) and maximum isolation of crop environment from surrounding environment, may be adopted in mushroom farming (Staunton, 1988). In India, button mushroom farming is largely restricted to temperate region, consisting of Indian states of Himachal Pradesh and Jammu-Kashmir. However, due to large consumer demand, its farming may also be adopted in adjoining states like Punjab and Rajasthan by technological interventions in mushroom houses (Kaur & Rampal, 2017; Kumar et al., 2018). The climate of these states is categorized as hot and semi-arid. Temperature (14-18°C) desired for button mushroom farming is available in hot and semi-arid region from December to February (for 2-3 months) during which one crop is easily grown. However, after March, ambient temperature increases sharply making button mushroom farming difficult in region. Therefore, an innovative mushroom house that can provide desired temperature for more duration (November to March) may prove good in the region for production of 2-3 crops of button mushrooms. Literature revealed that lot of research has been carried on mushroom production technology, development of mushroom varieties, post-harvest management of mushrooms etc. However, almost no work has been devoted on developing crop specific polyhouse suitable for farming of button mushrooms in hot region. Hence, an attempt was made in present study to develop intermediate cost, durable, completely protected polyhouse for mushroom farming. The main objective of study was to develop polyhouse for button mushroom farming in hot region of northwestern India and to evaluate its performance in terms of attaining desirable temperature and RH inside polyhouse during off-season period viz. October, November and March. 2 Materials and Methods 2.1 Experimental site Experimental site is located in hot and semi-arid region of northwestern India. This region comprises of parts of Punjab, Haryana and Rajasthan. Description of experimental site is presented in Table 1. Mean monthly temperature and RH data was recorded at experimental site prior to study. This data indicated that maximum temperature in May-July reached up to 49°C whereas minimum temperature in December-January dropped to 0°C. Atmospheric RH dropped to 10% during May-June. This data revealed that polyhouse proposed for button mushroom farming should be capable of lowering the temperature by reducing heat gain during October, November and March months. Similarly, it should be able to increase inside temperature to optimum level by preventing heat loss during chilling winter. 2.2 Development of mushroom polyhouse Crop specific polyhouse was developed according to functional requirement of button mushroom crop. Its roof was insulated and walls were ventilated (Figure1). The details of the structural components of polyhouseare presented below. Orientation - east-west direction Dimensions - length - 15 m, width - 4 m, ridge height - 4.27 m Roof - ridge height from floor: 4.27 m; eve height from floor - 2.13 m. Multi-layer roof composed of iron net (half inch mesh), polythene sheet (0.025 mm thick), jute sheet (3 mm thick), EPF thermocol sheet (8 mm thick) and UV stabilized polythene sheet (0.4 mm thick). Thermal conductivities of all these materials are listed in Table 2. Floor - floor material: single layer vertical brick. Floor of polyhouse was kept at 1 m deep below ground level. Aim of lowering the floor was to provide extra height to polyhouse with minimized risk of overturning due to strong winds. It was also aimed at achieving more cooling effect through evaporative cooling system. Foundation walls - height - 1.22 m, width – 0.2 m Walls - Front wall- center height - 4.27 m. Front wall was provided with two 18 inch exhaust fans. Rear wall – center height was- 4.27 m. Side walls - composed of foundation wall (lower half) made of brick - 1.22 m height; and porous wall (upper half) made of insect proof net and UV-stabilized polythene. Door - double door frame was used to prevent the entry of insects and pests in to the structure. 2.3 Temperature profile inside polyhouse After its construction, temperatures at nine different locations inside polyhouse were recorded under no crop load condition. Temperature sensors (PT 100 probes) of datalogger (sixteen channel, make: Intronix India, New Delhi) were installed in a grid of three tiers having three thermometers in a tier at nine locations (Figure 2). Temperatures were recorded at an interval of 30 min. The data was recorded continuously for six months. No cooling was provided to polyhouse during this period. 2.4 Heat load analysis of polyhouse Heat load analysis was carried out using different equations described by Holman (1989). Heat load was the total heat accounted for increasing inside temperature of polyhouse. Total heat gained (QT) inside polyhouse was due to, heat inflow from surroundings (QS) heat generated by compost (QC) heat generated by workers (QW) heat generated by data logger, battery etc. (QD) QT = QS + QC + QW + QD However, amount QC ,QW and QD were very small in comparison to QS (QC>> QC , QW, QD ). Hence only QS was considered for heat load analysis during study. QS had two components: heat gained through roof (QR) and heat gained through walls (QW).Surface areas of roof and wallsexposed to surrounding were determined using Figure 3. Roof surface area (AR) was calculated as 89.38 m2 whereas wall surface area (AW) was 66.23 m2. Heat gained through roof (QR) was determined using Eq.1. QR=URARΔT …(1) UR was determined using Eq.2 1UR=1hi+xPKP+xJKJ+xFKF+xUKU+ 1ho …(2) Where, QR = heat gained through roof (W) UR = overall heat transfer coefficient of roof (W/m2K) = 2.29 AR = roof area (m2) ?T = temperature difference of inside and outside of roof (°C) h= convective heat transfer coefficient of air at low speed (W/m2.K) X = layer thickness(XP= polythene, XJ= jute, XF= foam, XU= UV stabilized polythene) K = thermal conductivity of layers (KP= polythene, KJ= jute, KPF= foam, KU= UV-stabilized polythene) Heat gained through wall (QW) was determined using Eq.3. QW=UWAWΔT …(3) UW was determined using Eq.4 1UW=1hi+xUK+ 1ho …(4) Where, UW = overall heat transfer coefficient of wall (W/m2.K) = 9.12 AW = surface area of wall (m2) ?T = temperature difference of inside and outside of wall (°C) 2.5 Cooling of mushroom polyhouse Two evaporative cooling systems, fogger and fan-fad, were installed to attain desired temperature and RH conditions inside polyhouse. 2.6 Foggers During spawn and case run polyhouse should be closed with no air exchange in order to achieve desirable CO2 concentration (Maheshwari, 2013). Therefore, during this period cooling is possible with foggers only. Fan-pad system would reduce CO2 concentration and hence may not be advisable. Six overhead foggers having total discharge of 24 liters/h were installed along the ridge line of the polyhouse. 2.7 Fan-pad system It was useful during fruiting period as air exchange is desirable during fruiting stage. The cooling pad was made of khus (Chrysopogon zizanioides) with dimensions as length 3.96 m, height 1.37 m and thickness 3-4 cm. The reason behind selecting khus as padding materials over other organic materials was that air flow through khus pad was higher as compared to wood wool and coconut coir pad (Shekhar et al., 2016). Khus pads were tied to galvanized iron wire mesh to prepare a cooling pad. Two electric exhaust fans with 4 straight blades and 18 inches sweep were used for achieving air exchange in polyhouse. |
AMGA (2004) The Australian Mushroom Growers Association (AMGA), Locked Bag 3, 2 Forbes St., Windsor, NSW, 2756, Australia.
Anonymous (2017) Horticultural statistics at a glance 2017. Published by Horticulture Statistics Division, Department of Agriculture, Cooperation & Farmers Welfare, Ministry of Agriculture & Farmers Welfare, Government of India, Pp:16.
Arumuganathan T, Rai RD, Tewari RP, Kumar R, Khare V, Kamal S (2010) Cultivation of white button mushroom (Agaricus bisporus) under evaporatively-cooled mud house condition. Bangladesh Journal of Mushroom4: 13-18.
Chang R (1996) Functional properties of edible mushrooms. Nutrition Reviews 54: S91–S93.
Dhar BL, Arumuganathan T (2005) Farm design for white button mushroom cultivation. Technical bulletin, National Research Centre for Mushroom, Solan.,Pp. 17.
Han JH, Kwon HJ, Yoon JY, Kim K, Namb SW, Son JE (2009) Analysis of the thermal environment in a mushroom house using sensible heat balance and 3-D computational fluid dynamics. Biosystem Engineering 104: 417-424.
Holman JP (1989) Heat Transfer. McGraw-Hill Book Co., New York
Karthick K, Hamsalakshmi D (2017) Current scenario of mushroom industry in India. International Journal of Commerce &Management Research3: 23-26.
Kaur AP, Rampal VK (2017) Assessment of casing mixtures on yield potential and quality of button mushroom (Agaricus bisporus) – on farm trial. International Journal of Current Microbiology and Applied Sciences 6: 430-436.
Kumar B, Kumari C, Kumar M (2018) Comparative Study of the Nutritional Content of White Button Mushroom [Agaricus bisporus (Lange) Imbach] after Application of Pseudomonas putida. International Journal of Current Microbiology & Applied Sciences7: 2210-2215.
Kwon H, Kang SW, Cho SB (2004) Mushroom growing houses. In: Oyster mushroom cultivation, Mushroom Grower’s Handbook 1, Mush World., Chapter 6, Pp. 129-134.
Mabveni ARS (2004) Mushroom cultivation in Zimbabwe. In: Oyster mushroom cultivation, Mushroom Grower’s Handbook 1, Mush World., Chapter 10, Pp. 212-219.
Maheshwari SA (2013) Guide for white button mushroom (Agaricus bisporus) production. Open Access Scientific Reports 2 : 1-4. doi.org/10.4172/scientificreports668.
Mehta BK, Jain SK, Sharma GP, Doshi A, Jain HK (2011) Cultivation of button mushroom and its processing: a techno-economic feasibility. International Journal of Advanced Biotechnology & Research 2: 201-207.
Reyes RG, Abella EA, Eguchi F, Iijima T, Higaki M, Quimio TH (2004) Growing paddy straw mushrooms. In: Oyster mushroom cultivation, Mushroom Grower’s Handbook 1, Mush World., Chapter 11, Pp. 248-255.
Sarker NC, Hossain MM, Sultana N, Mian IH, Karim AJMS, Amin SMR (2008) Relationship between nutrient content in substrates and economic yield of oyster mushroom (Pleurotusostreatus). Bangladesh Journal ofMushroom2: 27-33.
Schiau HG (2013) An investigation of the airflow in mushroom growing structures for modelling new structures. 5th International Conference on Computational Mechanics and Virtual Engineering, 24- 25 October 2013, Brasov, Romania, Pp. 423-429.
Schmidt EL (1983) Spore germination of and carbohydrate colonization by Morchella esculenta at different soil temperatures. Mycologia75: 870–875.
Shekhar S, Suman S, Moharana HS, Sethy DA (2016) Comparative study of performance of six different pad materials in advanced desert coolers. Recent Advances in Mechanical Engineering & Engineering Materials 250-254.
Stamets P (1993) Cultivating morels mushroom. The Journal of Wild Mushrooming 11: 9–15.
Staunton L (1988) The role of plastics inthe development of the Irish mushroom industry. Plasticulture 79: 22-26.
Thakur MP (2014) Present status and future prospects of tropical mushroom cultivation in India: A review. Indian Phytopathology 67: 113-125.
Van Peer AF, Muller WH, Boekhout T, Lugones LG, Wosten HA (2009) Cytoplasmic continuity revisited: closure of septa of the filamentous fungus Schizophyllum commune in response to environmental conditions. PLoSONE 4 : e5977. https://doi.org/10.1371/journal.pone.0005977.
http://agridaksh.iasri.res.in/html_file/mushroom/white_button_mush.htm access on 25th July, 2018.