Se-domestication Of The Superior Strains Of Lentinula Edodes

As a fungus for eating and medical use, shiitake will be greatly improved in nutritional and medicinal value in Se accumulation, thus the development and utilization of selenium-enriched mushroom has great significance. This study use 22 main shiitake varieties in Qinba mountain area, through the mycelial growth situation、colonial form observation, ITS genetic sequences and phylogenetic tree structure were also analyzed to define the germplasm resources and genetic relationship in different varieties, finally filtered out 7 good strains, finally 808 and Wu Xiang 1st were gained after Se enrichment training by c PDA flat, and comprehensively analyzed stiitakes growth states,hyphae form,mycelium diameter and colony morphology. The best substitute cultivation recipes were screened by the improvement of liquid Se fermentation with the strain of 808 as material, which have the relatively high biotransformation quantity and vigorous growth potential. The main results are as follows:1.Good srains’ breedingBy the research of Qinba mountain area’s 22 cold-resistance stiitake strains of hypha growth rate, morphological characteristics, color, density, ITS genetic sequence determination and mushroom strains phylogenetic tree construction research, the results prove that 808, Jin Xi 1st, Tai Xiang, 507, Hu Nong 3st, Han 8, Wu Xiangan 1 st, because the genetic relationships between each other, hypha growth rate faster and Mycelium density, so we select them as good strains breeding of Shiitake selenium- accumulation.2. Flat selenium- accumulation medium domesticationLentinula edodes were domesticated in the c PDA flat selenium- accumulation medium domesticates, the result shows the best growth of selenium resistant mushroom when the concentration of Na2 Se O3 is 60mg/L, Shiitake mushroom808 and Wuxiang1 own the neat colony edge, dense hyphae and white color, which were selected for strains of liquid seleniumaccumulation fermentation domestication.3.Liquid selenium- accumulation fermentation domesticationTreat liquid selenium to fermentation domestication on lentinula edodes808 and Wu Xiang1, by observating on mushroom hypha’s microstructure,measuring and analysing biological conversion amount(wet weight) shows 60 mg/L concentration of Na2 Se O3 lentinula edodes is the best selenium concentration,under this concentration, Shiitake mushroom808 has thicker hyphae, larger biological conversion amount at5.3258 g/L. So we choose lentinula edodes808 for selenium- accumulation shiitake study on superior high preliminary cultivation technology.4. Cultivation on selenium-accumulation mushroomsBy selenium- accumulation domestication on lentinula edodes808’s original species, cultivated species cultivation and efficient mushroom cultivation. Analyzing shiitake808 strain’s hypha spawn running time, fruiting time and the situation of sporocarp growth and development, the results indicating culture material.3 is the most suitable for selenium- accumulation mushrooms growing, culture material composes: Mulberry wood(38%), cotton seed hull(28%), corncob(20%), wheat bran(10%), brown sugar(1.5%), gypsum powder(2%), superphosphate calcium(0.5%), carbamide(0.5%), water content 60%. Na2 Se O3 concentration for 60mg/kg.Culture material 1.67 kg per bag on average, picking 808 of bred quantity is 0.65 kg.5.The analysis of the nutritionAnalysing selenuim-accumulation shiitake 808 undomesticated strain sporocarp’s nutrition ingredient, it’s shows that the concentration of Na2 Se O3 is 60 mg/kg compared with Na2 Se O3 is 0,he latter’s water content reduced by 13.73%, ash redused by 18.60%, crude fiber reduced by 21.08%, crude protein increased by 27.24%, crude fat increased by 8.40%, carbohydrates increased by 7.35%.it’s shows that the concentration of Na2 Se O3 is 60 mg/kg compared with Na2 Se O3 is 0 shiitake 808 domesticated strain has changed after domestication,ash redused by 20.88%, crude fiber reduced by 22.59%, crude fat redused by 12.67%, water content increased by 8.54%, crude protein increased by 30.16%, carbohydrates increased by 8.23%6.The analysis of amino acid’s compositionAnalyzing the amino acid’s composition of selenium-rich shiitake’sporocarp,it shows that, when Na2 Se O3 concentration is 60 mg/kg, 808 amino acids in the sporocarp has improved more substantial than that without selenium in the sporocarp, total content is 191.69 mg/g, increased by 30.32%.7. The selenium detectionBy digestion-double channel atomic fluorescence, detecting the seleium content in shiitake sporocarp,which attains to 6.05 × 10-3 mg/kg of mushroom dry weight in shiitake 808 domesticated strains sporocarp selenium content, and 4.20×10-3 mg/kg in undomesticated shiitake.