A field experiment to study the “Comparative efficiency of organics and biofertilizers on growth and yield of maize (Zea mays L.)” was conducted during Kharif 2011 at farmer field in Beluguli village, Chikkanayakanahalli taluk (Tumkur district). The maize cultivar Nithyashree (NAH 2049) was used in the study. The field experiment was laid out in Randomized Complete Block Design with fourteen treatments and three replications. Results of the treatment (T13) having recommended dose of NPK + Azotobacter chroococcum + Bacillus megaterium + Pseudomonas fluorescence + enriched compost has showed highest plant height at 30, 60, 90 days after sowing and at harvest (120 days) (31.70, 180.93, 186.07 and 188.13 cm respectively). The highest total dry matter production at harvest (375.80 g) and yield parameters like Weight of cob (207.63 g), Grain yield per plant (158.93 g), Grain yield per ha (54.53 q) and Test weight of seeds (33.10 g) was also found highest in this treatment and available nutrient content in soil after crop harvest i.e., nitrogen (185.40 Kg ha-1), phosphorous (38.83 Kg ha-1) and potassium (181.47 Kg ha-1) was also found highest in the same treatment combination.
Influence of biofertilizers and different sources of organics on growth of maize.
The germination was not significantly influenced by treatments. However, maximum germination was recorded (96.90%) with the application of recommended dose of NPK + A. chroococcum + B. megaterium+ P. fluorescence+ enriched compost(T13).This is due to better soil condition with application of organics and biofertilizers. This is in conformity with the results of Amruthesh et al. (2003) and Hameeda et al. (2008) who observed such increased germination due to biofertilizers application. Among the different growth parameters, significant increase in the plant height was observed till the end of crop growth period. The treatment (T13) receiving recommended dose of NPK + A. chroococcum + B. megaterium+ P. fluorescence+ enriched compostrecorded maximum plant height at 30, 60, 90 days after sowing and at harvest (31.77, 180.93, 186.07 and 188.13 cm). Increased plant height may be due to the application of recommended dose of NPK and microbial consortia of nitrogen fixer, phosphate solubilizer and PGPR bacterium with nutrient rich organic source like enriched compost. The increase in growth of maize could be attributed to the enhanced nutrient use efficiency in the presence of organic fertilizer. Many organic materials release nutrients slowly and may reduce the leaching losses, particularly N (Nevens and Reheul, 2003 and Naveed et al. 2008).The number of days taken for fifty per cent tasseling by maize did not differed significantly due to treatment effects. However, maximum days taken for fifty per cent tasseling were recorded (51.87 days) with recommended dose of NPK + A. chroococcum + B. megaterium+ P. fluorescence+ enriched compost (T13).
The findings of this study have clearly showed that combined application of Azotobacter chroococcum, Bacillus megateriumand Pseudomonas fluorescence along with recommended dose of NPK and enriched compost has resulted in obtaining highest plant growth, crop yields and dry matter production.