In searching for new strategies of medicinal plant production with high yield but without undesirable compounds or effects, it is important to investigate unconventional alternatives such as application of Plant Growth Promoting Rhizobacteria (PGPRs) and cover crops cultivation. This experiment was conducted in a split plots arrangement with two factors based on a Randomized Complete Block Design (RCBD) with three replications during years 2009-10, at Research Farm of Ferdowsi University of Mashhad. Cultivation and no cultivation of cover crops in autumn considered to the main plots. The sub plot factor was biofertilizer application with four levels, included 1-Nitroxin (containing Azotobacter spp. and Azospirillum spp.), 2-Biophosphorous (containing Bacillus sp. and Pseudomonas sp.), 3-Nitroxin + Biophosphorous and 4-Control. The results showed that the highest and the lowest of Leaf Are Index (LAI) and Green Area Index (GAI) were obtained in plants treated by Nitroxin without cover crop and biophosphorous with cover crop, respectively. Plants harvested in 3 times during the growing season and the third harvest had the lowest LAI and other two harvests had no significant difference concerning this trait. The highest and the lowest fresh and dry shoot yield were obtained in the second and the first harvest, respectively. The most essential oil yield obtained from the second and the third harvest (without significant difference) and the first harvest was the lowest. The results showed that the interaction between biofertilizers and no cover crop cultivation was significant, as use of the biofertilizers especially Nitroxin and biophosphorous in no cover crop condition enhanced the most characteristics of basil in an ecological production system framework.

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