The production of seedlings is very important in the horticultural transplant industry and depends on the substrate utilization. The use of coconut coir fiber alone was evaluated or in combination with other potting media to produce transplants of tomato cv. 'Santa Adélia'. Cococnut coir fiber potting media PlantmaxÒ and earthworm castings were tested separated and in volumetric combinations: PlantmaxÒ + cocunut coir fiber, worm cast + cocunut coir fiber, PlantmaxÒ + earthworm casting and PlantmaxÒ + coconut coir fiber + earthworm casting, evaluating the variables germination 10 days after planting, leaf number, plant height, shoot fresh matter and shoot dry matter at 25 days after planting. The mixed substrates were superior to those from single components mainly PlantmaxÒ + coconut coir fiber + earthworm casting. The indigenous microbial population in each one of the three substrates was quantified in relation to the variables total bacteria, total fungi, fluorescent Pseudomonas spp., Bacillus and Trichoderma. In coconut coir fiber and earthworm casting the bacterial population surpassed the fungal. Earthworm casting and coconut coir fiber showed respectively higher population of total bacteria (240.56 x 10(4) UFC/g of dry substrate) and total fungi (86.98 x 10(4) UFC/g of dry substrate). Fluorescent Pseudomonas spp. were detected in earthworm casting (1.65 x 10(4) UFC/g of dry substrate) and PlantmaxÒ (0.36 x 10(4) UFC/g of dry substrate); Bacillus spp. in earthworm casting (33.23 x 10(4) UFC/g of dry substrate) and, Trichoderma spp. only in coconut coir fiber (2.42 x 10(4) UFC/g of dry substrate). To evaluate the effect of increment of the indigenous microbial population of substrates in promotion of seedlings growth of tomato PlantmaxÒ + coconut coir fiber + earthworm casting suspensions of five isolates of Trichoderma spp.; four isolates of fluorescent Pseudomonas spp., five isolates of Bacillus and the mixed of the isolates Trichoderma + fluorescent Pseudomonas spp. + Bacillus were added. The suspensions were added two days before planting, on concentrations of 0.52 A and 5x10(6) conidia/mL to bacteria and fungi, respectively. The increment of microbial population did not affect the growth of tomato seedlings. In conclusion, the utilization of the coconut coir fiber mixed with other substrates, mainly PlantmaxÒ, is viable reducing the costs of tomato seedling production.
Lycopersicon esculentum; fluorescent Pseudomonas spp.; Bacillus spp.; Trichoderma spp; coconut coir fiber; PlantmaxÒ; earthworm casting; fungi; bacteria
