Effect of seed treatment using Mancozeb and Ridomil fungicides on Rhizobium strain performance, nodulation and yield of soybean (Glycine max L.)

Abstract

The viability of commercial Rhizobium strains (SB-14 and SB-12) were inoculated and fungicides (Mancozeb and Ridomil) were used as seed dressed on soybean seed to investigate their effect on nodulation, plant growth and seed yield of soybean. Application of Rhizobial inoculants alone gave the highest nodulation and shoot dry weight performance as well as seed yield of soybean on both sites. SB-12 inoculant had significantly shown to be more effective than SB-14 inoculant in increasing nodulation and thus produced higher plant growth and seed yield. Rhizobial survival on the seeds was severely affected by both fungicides, resulting in decreased nodulation, plant growth and seed yield for both inoculants. However, Ridomil fungicide gave the lowest nodulation and seed yield when applied with either SB-12 or SB-14 Rhizobial strains. The strains differed in their sensitivity to Mancozeb fungicide that with strain SB-12 showed a slight effect or no effect on survival of rhizobium, nodulation and yield of soybean. Seed-dressing of mancozeb and ridomil resulted in reduction of seed yield by 882.8 kg ha-1 and 1154.7 kg ha-1, respectively with SB-12 strain. The present results indicate that inoculated Rhizobium inoculants differ in their capacity to develop resistance to the two dressed fungicides. Seed treatment with Mancozeb in combination with SB-12 strain slightly affected the survival of the inoculated strain. Consequently, mancozeb fungicide may be compatable with survival of the inoculated SB-12 Rhizobia. The results also indicate that the suppressive effects of seed-applied fungicides on Rhizobium strains survival and nodulation development depend on specific strain and fungicide. Soybean seeds inoculated with SB-12 may not need management with fungicides or lower concentration of Mancozeb that could be compatible with SB-12 to suppress soil-borne pathogens for both Assosa and Begi sites, western Ethiopia.

Microbiological, Antioxidant, Nutritional Properties, and Health Safety of Juice from Organic and Conventional Vitis vinifera L. Farming

“…However, it should be noted that the ecological parameters assessing diversity and dominance among bacteria did not show significant differences based on the type of cultivation.The cultivation method has a significant effect on bacteria, especially their quantitative representation of the fruit, and indirectly influences their diversity. Previous studies have indicated the negative effect of fungicides on bacteria (reduction in abundance or elimination) (Gu et al, 2010;Getachew and Abeble, 2021;Ma et al, 2021). Consequently, fungicides may reduce bacterial diversity and the number of bacteria on the fruit, potentially weakening the fruit's natural biological defense against pathogens.…”

Realization of protective and symbiotic properties of soybeans using fungicide seed treatment

“…The plants of the family Fabaceae in the symbiosis with nodule bacteria (Rhizobiaceae) form an active symbiotic apparatus, and a combination of all the measures, aimed at the optimization of this process, promotes the realization of their nitrogen-fi xation potential (Joshi et al, 2014). At present, there are active studies on the possibility of using seed inoculation with nodule bacteria prior the planting to regulate the metabolism of legumes and enhance their tolerance to biotic effects (Dicheng et al, 2018;Standish et al, 2018;Alonso-Monge et al, 2020;Laktionov et al, 2020;Rathjen et al, 2020;Getachew et al, 2021;Martinez et al, 2021;Santos et el, 2021).…”