The Effect of Plant Growth-Promoting Rhizobacteria, Filter Cake, and Herbicide on the Photosynthetic Pigments and Growth Components of Spinach Plant

In order to investigate the impact of plant growth-promoting Pseudomonads isolates and filter cake on the alterations of chlorophyll pigments and growth components in spinach plant under metribuzin herbicide stress, a factorial experiment was conducted as completely randomized blocks at the greenhouse of the Department of Soil Science of the Agricultural Sciences and the Natural Resources University of Khuzestan in 2018-2019.

In this study, Pseudomonas alloputida RUM14 and P. protegens CHA0 were used as PGPR isolates and filter cake was utilized as organic fertilizer.

Statistical analysis of the study’s results indicated that treating spinach plants with Pseudomonas alloputida RUM14, P. protegens CHA0, and filter cake significantly increases chlorophyll a (47, 21, 29%, respectively) and b pigments (42, 20, 18%, respectviely) and carotenoids (96, 33 and 84%) and also increases the dry weight of root (respectively 59, 30, 45%), length of root (108, 51, 53%), dry weight of stem (56, 49, 13%) and the stem length (31, 19, 14%). Statistical analysis clarified that applying metribuzin herbicide at the rate of 100 grams per hectare dramatically reduces the content of photosynthetic pigments and growth components. However, utilization of growth-promoting rhizobacteria and filter cake effectively decrease the extent of such damage.

The results of this investigation clarified for the first time that the use of Pseudomonads plant growth-promoting rhizobacteria and/or filer cake, significantly enhance the photosynthetic pigments and growth components of spinach plant. Additionally, the mentioned treatments reduce the damage caused by metribuzin herbicide application.