Use of lychee pruning compost and vermicompost as carriers of Priestia megaterium
This study aimed to evaluate the feasibility of lychee pruning compost and vermicompost to replace peat as carriers of Priestia megaterium.In the present experiment,we produced six mixed carriers of the target bacteria,P.megaterium,by using different ratios of lychee pruning compost,vermicompost,and peat;we labelled these different mixes as ST1,ST2,ST3,ST4,ST5,and ST6 with mass ratios of 6∶2∶2,4∶2∶4,2∶2∶6,6∶3∶1,4∶3∶3,and 2∶3∶5,respectively.The peat(CK)alone was used as the control.We dynamically monitored the viable counts within the carriers at different cultivation times to determine which mixed carrier formula was suitable for the survival of P.megaterium.On this basis,we set different water contents(20%,30%,40%),temperatures(20,30,40,50℃),and inoculation concentrations(106,107,108 cfu·mL-1),and dynamically monitored the living bacteria;we then optimized the water content,temperature,and inoculation concentration of the carriers accordingly.The results showed that the viable count of each carrier initially decreased then increased with the cultivation time.ST2 and ST5 were determined to both be optimal carriers of P.megaterium,according to their high viable counts of P.megaterium after long term of cultivation and their relatively low peat composition.After 60 days of cultivation,with increasing water content and temperature,viable counts increased before decreasing;the highest viability counts were achieved at 30%water content(ST2 2.46×108 cfu·g-1,ST5 1.81×108 cfu·g-1)and at 30℃(ST2 3.44×108 cfu·g-1,ST5 1.87×108 cfu·g-1)and 40℃(ST2 8.50×107cfu·g-1,ST5 7.13×107cfu·g-1).Moreover,the viable count within the carrier at each cultivation stage increased with increasing inoculation concentrations;the viable counts of ST2 and ST5 reached 3.63×108 and 3.33×108 cfu·g-1,respectively,after 60 days of cultivation.Overall,the mixed carriers ST2 and ST5 are most suitable alternatives that can be used to replace peat as carriers of P.megaterium;the optimal conditions for these carriers are 30%water content,30-40℃temperature,and 108 cfu·mL-1 inoculation concentration.
万方数据
维普
