Effects Of Illumination Time And Intensity On The Growth And Physiology Of Pleurotus Eryngii

Light is an important environment factor that affects the growth and development of Pleurotus eryngii.In recent years,there have been many studies on the effects of light on the growth and development of P.eryngii,but most of them had focused on the effects of light quality,and few studies involved in the effect of illumination time and light intensity.To explore the effect of illumination time and light intensity on the growth and development of P.eryngii and its physiological effect,five kinds of illumination time(1 min light 29 min darkness,5 min light 25 min darkness,10 min light 20 min darkness,15 min light 15 min darkness,and 30 min light 1 s darkness)under red light,blue light and white light,and seven kinds of light intensity(0 lux,100 lux,500 lux,1000 lux,2000 lux,3000 lux and4000 lux)under white light were set to carry out cultivation test in our study,and the rate of primordial formation and differentiation,the morphology of bud and fruiting body,the yield,the activity of superoxide dismutase and catalase,the contents of soluble protein and total sugar,and the expression level of blue light receptor gene were determined.The results were as follows:(1)With the increase of illumination time,the primordial formation rate under the red light,blue light and white light showed a trend of increasing first and then decreasing.The rate was the fastest at a condition of 10 min light and 20 min darkness under red light,15 min light and 15 min darkness under blue light,at 10 min light and 20 min darkness under white light,respectively.(2)With the increase of illumination time,the primordial differentiation rate under red light showed a trend of increasing first and then slightly decreasing,while that under blue light and white light showed a trend of increasing.The rate was the fastest at a condition of 10 min light and 20 min darkness under red light,30 min light and 1s darkness under blue and white light,respectively.(3)The fruiting body under red light presented symmetrical shape,with smaller pileus,longer and thinner stipe.The stipe was the main part of the fruiting body and different illumination times had little effect on the shape of fruiting bodies;under blue and white light,the fruiting bodies have larger pileus,and shorter and thicker stipe,and the pileus occupied a certain proportion in the fruiting body,and with the increase of illumination time,the pileus was gradually larger,and the stipe was shorter.The fruiting body yield was higher under red light,blue light,and white light with 1 min light and 29 min darkness,and 5 min light and 25 min darkness.(4)The activity of superoxide dismutase and catalase differs significantly under different illumination times and the influence of different illumination time under the different growth stage were different.The enzyme activity was lower under red light with more illumination time and was lower at10 min light 20 min darkness and 15 min light 15 min darkness that moderate illumination time under blue light and was lower at 15 min light 15 min darkness under white light.(5)Different illumination times had a great impact on the soluble protein contents in the fruiting body,but less on the total sugar contents.The soluble protein content was lower at 10 min light 20 min darkness and 15 min light 15 min darkness,and higher at 1 min light 29 min darkness and 5 min light25 min darkness and 30 min light 1 s darkness under red,blue and white light.The total sugar contentunder red light was no significant difference among different illumination time groups.But that under blue light was the highest at 5 min light 25 min darkness and the lowest at 30 min light 1 s darkness while that under white light was the highest at 30 min light and 1 s darkness,and the lowest at 15 min light and 15 min darkness.Different light intensities had less effect on soluble protein content and greater influence on total sugar content.The soluble protein content was the highest at 100 lux and the lowest at 3000 lux.The total sugar content was the highest at 3000 lux and the lowest at 0 lux,and and it tended to increase with the increase of light intensity.(6)The relative expression levels of blue light receptor genes in the primordium stage and bud stage under blue light and primordium stage,bud stage,fruiting body stage under different white light intensity were significantly affected by different illumination time,however,the overall trend of the relative expression of the blue light receptor gene was similar under different illumination time,all of which showed a trend of decreasing first and then increasing with the growth process.However,the relative expression level of blue light receptor gene was relatively higher in the primordium stage under different white light intensity,and gradually decreased in the bud to fruiting body stage.(7)The primordium could form but could not differentiate in the dark.With the increase of light intensity,the stipe length changed little,but the pileus diameter gradually increased,while the yield increased first and then decreased.The fresh weight of fruiting body and biological efficiency in each bag was higher at 1000 lux,2000 lux and 3000 lux,and the commodity rate was higher at 1000 lux and2000 lux.