3.2. Symbiotic seed germination of D. fimbriatumIn this experiment, we used the plastic box (Fig. 3a) as the seed germinationcontainer to provide more room to larger orchid protocormsand tomake themethodmore feasible for orchid growers and hobbyists.Initially, each treatment consisted of nine replicates. However, contaminationoccurred in some experimental units and the contaminated unitswere excluded from the data analyses. Number of replicates of eachtreatment used in the data analysis is shown in Table 2. Seeds ofD. fimbriatum sown on peatmoss in all treatmentswere observed to germinateat two weeks after sowing. At 17 weeks after sowing, germinationpercentages of seeds in the two treatments with mycorrhizalinoculation were higher than that of seeds in the un-inoculated controlbut only seeds co-cultured with T. deliquescens isolate Da-KP-0-1 hadsignificantly higher germination percentage (Table 2). According tothis study, both fungal isolates (i.e., Da-KP-0-1 and Pv-PC-1-1) werefully compatible with D. fimbriatum since they supported the orchidprotocorms to the most advanced seedling stage (i.e., seedlings withelongated leaves and roots). Protocorms on peat moss without the mycorrhizalfungus did not develop beyond Stage 3 (Table 2). Microscopicobservation revealed pelotons in the protocorms co-cultured witheither fungal isolate Da-KP-0-1 or Pv-PC-1-1 and the absence of pelotonsin protocorms in the un-inoculated treatment (data not shown). Thisexperiment demonstrated that peat moss could be used as germinationsubstrate for in vitro symbiotic seed germination of orchid, althoughthe rates of seed germination in all treatments were unusuallylow as compared to seed germination rates of Dendrobium orchids(Swangmaneecharern et al. 2012), probably due to the waterloggedcharacteristic of the peat moss observed in the germination boxes(data not shown). Therefore, in our next experiment we modified thegermination method to solve the mentioned problems and also comparedthe effectiveness of the method to OMA and 1/5MS.