Effects of growth promoting microorganisms on tomato seedlings growing in different media conditions

Abstract

Plant growth-promoting microbes (PGPM) play vital roles in maintaining crop fitness and soil health in stressed environments. Research have included analysis-based cultivation of soil-microbial-plant relationships to clarify microbiota potential. The goal of the research was to (i) evaluate the symbiotic microorganism effects on tomato seedling fitness under stressed conditions simulating a fragile soil susceptible to degradation; (ii) compare the plant-microbial interactions after inoculation with microbial isolates and fungi-bacteria consortia; (iii) develop an effective crop-microbial network, which improves soil and plant status. The experimental design included non-inoculated treatments with peat and sand at ratios of 50:50, 70:30, 100:0 (v:v), inoculated treatments with arbuscular mycorrhizal fungi (AMF) and Azospirillum brasilense (AZ) using the aforementioned peat:sand ratios; and treatment with peat co-inoculated with AMF and Saccharothrix tamanrassetensis (S). AMF + AZ increased root fresh weight in peat substrate compared to the control (4.4 to 3.3 g plant–1). An increase in shoot fresh weight was detected in the AMF + AZ treatment with a 50:50 peat:sand ratio (10.1 to 8.5 g plant-1). AMF + AZ reduced antioxidant activity (DPPH) (18–34%) in leaves, whereas AMF + S had the highest DPPH in leaves and roots (45%). Total leaf phenolic content was higher in control with a decreased proportion of peat. Peroxidase activity was enhanced in AMF + AZ and AMF + S treatments, except for AMF + AZ in peat. Microscopic root assays revealed the ability of AMF to establish strong fungal-tomato symbiosis; the colonization rate was 78–89%. AMF + AZ accelerated K and Mg accumulation in tomato leaves in treatments reflecting soil stress. To date, there has been no relevant information regarding the successful AMF and Saccharothrix co-inoculation relationship. This study confirmed that AMF + S could increase the P, S, and Fe status of seedlings under high organic C content conditions. The improved tomato growth and nutrient acquisition demonstrated the potential of PGPM colonization under degraded soil conditions.

Growth and Production of Lycopersicon esculentum M. with Rhizophagus intraradices and Azospirillum brasilense in a Substrate with Chicken Manure Added

“…"In the morphological components of yield, the increase in height of biofertilized plants reflects the benefits of the symbiosis of L. esculentum M. with R. intraradices and A. brasilense alone or in co-inoculation" [27]. Authors such as Pokluda et al [28] mention similar results in the height of tomato seedlings var "Amalia" superior to 23% with the co-inoculation of Azospirillum brasilense and Glomus clarum in comparison to the control. Alvarado Carrillo [29] reported that plant height of L. esculentum var "El Cid" (Saladette type) increased 12% with mycorrhization.…”

Serendipita indica as a Plant Growth Promoter and Biocontrol Agent against Black Rot Disease in Cabbage Grown in a Phytotron

“…Confocal microscopy was conducted using the LSM 800 microscope (Carl Zeiss, Jena, Germany) at 590/617 nm excitation/emission for WGA AF 594, 650/668 nm for Con A AF 647, and 350/461 nm for Hoechst stain, using a 20 × 0.8 NA lens. The pictures were processed in Zen Blue 3.0 (Carl Zeiss, Jena, Germany) [23].…”