Studies on Genetic Variability, Interspecific Hybridization And Spawn Quality of Pleurotus Species

Abstract

Oyster mushroom 1s Important among the mushroom grown in lnd1a as well as 1n wortd having nutnt1ve value and various uses. The five species of oyster mushroom v1z Pleurotus sajo~ c~;u. Pleurotus Ronda, P/eurotus flabella/us. Pleurotus fossula/us and Pleurotus sapldus were d1fferent 1n morphology and y1eld performance Radial growth of P. florida and P sap1dus were found max1mum 86.25 mm and 83.50 mm. respecbvely at 30°C whereas the growth of P. sajor csju (84 25 mm). P fossulatus (81.00 mm) and P flabella/us (7225 mm) at 25°C P. sa)Of ca;u and P. flabellatus exh1brted h1gher growth (90 mm and 77 66 mm, respectrvely) at 6.5 whereas rt was pH 7 0 for P. florida (90 mm). P fossula/us (90 mm) and P sapldus (88.66mm). The dry weight of mycelial growth of all Pleurotus spp was found maximum at pH 6 5-7 0 Radral growth of P. sa;or cs;u. P florida and P. flabetlatus was max1mum 1n potassium hydrogen sulphate whde P. fossulatus and P. sapidus grew best m magnes1um sulphate The zinc sulphate @1 per cent was able to inhrbit the growth of all five Pleurotus spp Max1mum spore germmat1on of Pleurotus speCieS was observed at 27"C and 7.0 pH level Sugar solutions were found to reduce the spore germ1nat1on as compared to check. Spore germination was Influenced by the period of storage. As the penod of storage increased. the spore germtnatlon was reduced but the reduct1on rn percentage was more 1n case of the spores stored at 27±1°C as compared to 8±1°C For hybnd1zat1on, the monospores cultures of Pleurotus spp. were screened on the bas1s of absence of clamp connection. Out of 100 paired, 27 were found compatible On the bas1s of yield performance, the hybrids of P sajor caju and P florida (Psc.xPfdl and PscycPfd,) gave maxtmum y1eld 536.60 g/Kg and 510 60 g/Kg of dry substrate, respectiVely Simitarty, In case of hybnds of P. sajor ca;u wrth P flabellatus and P fossula/us the hybnd Psc,xPfbs (603 20 g/Kg dry substrate) and hybrid Ps~Pfoss, (558 70 g/Kg dry substrate) gave m8XImum yield. While among the hybrids of P. sa;or ca;u and P sapidus. the Psc,xPsp1 gave maXImum yteld (666.56 g/Kg dry substrate) The wheat straw extract med1um was found most suitable for all hybrids and parents. For spawn preparation of P sajor ca;u. bo1hng of gra1n was found to be better than soaktng The optimum temperature for quality spawn preparation of P sa;or caju and P sap1dus was found 25°C and 27'C. respectJvely. Light had no any pronounced effect on spawn preparation Wheat bran. gram husk and nee husk were found to be the supenor substrate followed by other cereal and millet gram for spawn preparation Gratn spawn of P sa;or caju and P sap1dus were Significantly superior in term of yield. The higher rate of spawn (5%) 1ncreased the yteld and reduced the time taken for colonization of substrate as compare to other spawn rate. For cultivation of P sajor ca;u and P sapidus, paddy straw alone and tn comb1na11on of gram husk and sugarcane bagasse (3·1) is good substrate 1n term of yield as compared to wheat straw alone Addrtron of organrc supplements such as cotton cake. soybean nour and gram powder@ 5 per cent of dry substrate significantly 1ncreased the _yield. whereas addition of 1norganic supplemerrt (fertilizers) to the substrate was found reductton '" y1eld of both P sa;or CI.IJU and P. sap1dus than the control. By addrt1on of different chem1cal to the substrate, max1mum yreld and number of sporophores of P. sajor ca;u were observed 1n potass1um hydrogen sulphate followed by sahcyhc acid whtle P. sapidus show max•mum yteld of sporophores m magnesium sulphate only. P. sajor ca;u gave higher yield, when grown dunng Feb -Apnl followed by Oct·Oec whrle '" case of P sapidus m8XImum yte1c1 was reported'" Jan-April followed Oct-Dec.