Bioinoculants for growth enhancement of aromatic plants: Artemisia pallens and Origanum majorana

Abstract

The use of fertilizers is a common practice to improve soil fertility and increase crop yields. Chemical fertilizers have played a significant role in increasing crop yields, but their widespread use has led to environmental degradation and soil depletion. The continuing challenges in agro-ecosystem and environment require more sustainable solutions than chemical fertilizers. In recent years, there has been a growing interest in the use of biofertilizers as a sustainable alternative to chemical fertilizers. Biofertilizers are natural substances that improve soil fertility, modify soil microbiota and enhance plant growth. Cyanobacteria are one of the well-known bio inoculants for paddy crops. However, the use of cyanobacteria for other plants has not been very well documented. We screened certain cyanobacteria isolated from different natural environments as biofertilizers for certain aromatic plants. Artemisia pallens and Origanum majorana are two plants with aromatic compound productions. The aim of this study was to screen for enhancement in the growth and propagation of the plants for their yield using bio inoculants. Further air-dried, powdered plant materials of the aerial parts of A pallens and O. majorana were extracted using solvents ranging in polarity from non-polar (n-hexane), semi-polar (chloroform) and polar (acetone, methanol). These extracts were tested for antioxidant activity, several plant extracts showed antioxidant activity, with water exhibiting the greatest levels. The purpose of the experiment was to investigate the effects of bioinoculants on the growth of the test plant. Our observation showed that all the tested cyanobacterial strains i.e. KM1, KM2 and VM1, VM2, the bioinoculants, enhanced plant growth to various levels. KM1 and KM2 exhibited a greater ability to increase plant growth. This demonstrates that Artemisia's and Origanum’s growth and herbage output may be successfully enhanced by the use of cyanobacterial bioinoculants.