Comparative Assessment to Detect the Level of Indole-3-Acetic Acid in Different Crops as Wheat (Triticum Aestivum), Mustard (Brassica Juncea) and Carrot (Daucus Carota) after Long-Term Treatment with Biofertilizers and Tea Compost
Organic fertilizers support plant growth and is an alternative of synthetic fertilizers without environmental degradations. The objective of the present study was to detect the level of indole-3-acetic acid (IAA) in three different crops viz. wheat (Triticum aestivum), mustard (Brassica juncea) and carrot (Daucus carota) after long-term treatment with biofertilizers and tea compost. The plant hormones or plant growth regulators, mainly IAA estimations were done by methanol-extraction method followed by spectrophotometric analysis in the shoot of wheat and mustard and root of carrot. The results obtained that there was almost 3-fold increase significantly (P< 0.001) of IAA content of mustard and carrot crops when treated with biofertilizers (Azotobactersp. + Bacillus sp. + Pseudomonas sp.) + tea compost, in comparison with control. The crop plants treated with biofertilizer, tea compost and cowdung compost, also showed interesting results, in comparison to the control. For wheat crop, treatment with tea compost have resulted in more than 3-fold increase significantly (P<0.001) of IAA content in comparison to the control. It is concluded that an increasing trend of plant hormone after the application of biofertilizers as well as tea compost may be the modified form of auxin, accumulated in the plant tissues of wheat crop due to the application of molasses, as a component of liquid tea compost. For mustard and carrot, the reason may be the biosynthesis of auxin in plant by associated bacteria, which results in shoot-up of the IAA concentration in studied crops. However, investigations on plant hormones have become very important as the estimations of endogenous hormone level, can direct the application of exogenous hormone regulators, wherever needed, in order to achieve targeted growth of crops.
Keywords - Crop Plants; Wheat, Mustard and Carrot; Growth Regulator as Indole-3-Acetic Acid; Biofertilizers and Tea Compost; Auxin Hormone