Comparison of the Effect of Biological and Non-Biological Fertilizers on Quantitative, Qualitative and Phytochemical Properties of Garlic (Allium sativum L.)

Biofertilizers are one of the most important components of organic and sustainable agriculture. The correct use of these fertilizers can increase the quantitative and qualitative yield of agricultural products, reduce the consumption of some types of chemical fertilizers and protect the environment.

In order to investigate the effect of biofertilizers on quantitative, qualitative, and chemical properties of Garlic, an experiment was conducted in a randomized complete block design with 10 treatments and four replications. Treatments included nitroxin, bio-superphosphate, supernitroplas, humic acid alone and the combination of nitroxin+ bio-superphosphate, bio-superphosphate+ supernitroplas, nitroxin+ humic acid+ bio-superphosphate, bio-superphosphate+ supernitroplas+ humic acid, application of macro chemical fertilizer (N-P-K-S) and no application of fertilizer (chemical and biological) as the controls. The treatments were applied as a seed coating.

The results showed that nutrition with biofertilizers had a significant effect on plant yield, clove weight, number of cloves, bulb width, bulb length, plant height, number of leaves, contents of carbohydrate, antioxidants, phenols, and flavonoids of bulbs. Compared to the control of no fertilizer application, supernitroplas led to an increase of 22.7%, 39.3%, 25.5%, and 20.8% in the number of cloves, clove weight, bulb width, and bulb length, respectively. The average plant height in biofertilizers was 25.8% higher than the control of no fertilizer application. Supernitroplas treatment increased yield and number of leaves by 24.7% and 15.8%, respectively, compared to the control of no fertilizer application. Also, supernitroplas treatment increased the amount of antioxidants, phenols, and flavonoids by 58.8%, 62%, and 65.6%, respectively, compared to the control of no fertilizer application. In addition, supernitroplas biofertilizer resulted in a 44.5% increase in bulb carbohydrates.

Overall, since most nutrient treatments, especially supernitroplas, showed superiority in many traits over both controls (application of NPKS fertilizer and no fertilizer application), replacing biofertilizers with chemical fertilizers is highly recommended.