Combined Effects of Arbuscular Mycorrhizal Fungi, Plant Growth-Promoting Rhizobacteria, and Mineral Fertilization on the Physiological, Biochemical, and Nutritional Properties of Chilaca Chili Pepper (Capsicum annum L.)
Pepper fruits contain diverse primary and secondary metabolites, including ascorbic acid, carotenoids, phenolics, and flavonoids, which contribute to nutritional quality, antioxidant capacity, coloration, and consumer acceptance. Chilaca chili pepper (Capsicum annuum L.) is a Mexican cultivar valued for its distinctive flavor and pungency, representing a valuable resource for studying fruit quality and sustainable crop improvement. This study evaluated the individual and combined effects of arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) on growth, physiological responses, antioxidant activity, and fruit quality traits. Twelve treatments in a 3 × 2 × 2 factorial designs were evaluated for chlorophyll, soluble solids, biomass, APX and LOX activities, and vitamin C and capsaicin contents at three ripening stages (green, mid-red, and red). Enzyme activities were determined spectrophotometrically, and bioactive compounds were quantified from methanolic fruit extracts. Microbial inoculation primarily improved fruit physiological quality rather than vegetative growth. Biomass and growth traits showed no significant differences among treatments (p > 0.05), whereas biochemical responses exhibited distinct ripening-dependent patterns. APX activity, vitamin C, and capsaicin increased from green to mid-red stages and declined at full ripeness. Bacillus sp.-based treatments (T1 and T2) produced a significant transient increase in LOX activity during mid-ripening, while T7 showed a similar but weaker response. AMF progressively enhanced LOX activity and capsaicin accumulation in green fruits. PGPR effects were strain-dependent, with Bacillus sp. promoting early capsaicin accumulation and A. deleyi favoring higher levels during advanced ripening. Overall, AMF and PGPR differentially regulate antioxidant metabolism, vitamin C accumulation, and capsaicinoid biosynthesis while interacting with mineral fertilization to improve fruit quality. These findings support beneficial microorganisms as sustainable tools for enhancing nutrient-use efficiency and fruit nutritional and functional value without replacing mineral fertilization.
Overall, mycorrhizal fungal inoculation reshaped the chemical composition and the major bioactive compounds of Oregano, thereby enhancing its nutritional and antimicrobial potential.
Abstract The objective of this work was to evaluate the effect of arbuscular mycorrhizal fungi (AMF), the Ascophyllum nodosum seaweed extract, the Trichoderma harzianum fungus, and their combinations on the horticultural potential of strawberry plants grown in substrate in a greenhouse. Eight treatments were studied: the absence and presence of bioinputs, represented by AMF, A. nodosum (AN), T. harzianum (TH), AMF+AN, AMF+TH, AN+TH, and AMF+AN+TH, arranged in a randomized complete block design, with four replicates. Fruit yield and quality were evaluated. The use of bioinputs did not change fruit yield, but prolonged the end of the production cycle. Treatments TH and AMF improve fruit quality regarding total anthocyanin and flavonoid contents. The use of bioinputs improves fruit quality of strawberry plants, but has no effect on fruit yield.
Arthur Pegoraro Klein, H. A. Delevatti, Ana Júlia Schroeder Ely et al.· Pesquisa Agropecuária Brasil...· 0 citations
The increasing need for sustainable agricultural practices has intensified interest in seaweed-based biostimulants and plant growth-promoting rhizobacteria (PGPR) as eco-friendly alternatives to chemical fertilisers. This study examined the individual and combined effects of Sargassum wightii extract and PGPR strains (Azospirillum lipoferum TSA-6 and Bacillus megaterium TSB-3) on the growth and yield of tomato (PKM-1) under pot culture conditions. Seaweed extracts obtained through hot-water and solvent extraction were screened for phytochemicals and endogenous growth hormones (IAA, GA₃ and cytokinin). Among the six species analysed, S. wightii exhibited the highest levels of auxin (3.7 mg L-1) and cytokinin (4.9 mg L-1). Preliminary screening using crude extract showed that a 2.5 % concentration significantly enhanced germination, seedling vigour, root and shoot length and leaf area index. In the pot experiment, the integrated treatment comprising 75 % recommended dose of fertilisers (RDF) + 2.5 % S. wightii extract + A. lipoferum + B. megaterium (T8) recorded superior growth and yield attributes, including increased dry matter production, fruit number, fruit weight and total fruit yield, comparable to 100 % RDF. The results demonstrate that the combined application of S. wightii extract and PGPR can effectively enhance tomato productivity while reducing fertiliser usage by 25 %. This integrated biostimulant strategy offers a sustainable approach to improving crop performance and reducing chemical fertiliser dependence.
K. Oviya, J. Jaipriyanka, S. Mahalakshmi et al.· Plant Science Today· 0 citations
ABSTRACT The pistachio tree (Pistacia vera L.) is a globally valuable nut tree due to its economic and nutritional properties. Sustainable management strategies, including microbial biostimulants such as biochar (Bc), Trichoderma and arbuscular mycorrhizal fungi (AMF), have been proposed to enhance tree performance under variable environmental conditions. This study investigated the combined effects of Trichoderma harzianum Rifai KRL-AG2, two different Bc rates (1% and 3%) and the commercial AMF Endo Roots Soluble on the growth, physiological performance, leaf nutrient content and soil microbial activity of 3-year-old pistachio trees in Adıyaman, Türkiye. Two sampling periods were considered to capture the early (May) and late (September) growth stages. Morphological assessments included shoot length, stem diameter and branch number, while physiological assessments covered photosynthetic efficiency index (PEI), chlorophyll content and leaf colour. Soil pH, electrical conductivity and AMF spore density were also evaluated. At the beginning of the season, Trichoderma and 1% Bc significantly increased shoot length, stem thickening and branch formation compared to the control group, while AMF synergistically improved physiological performance towards the end of the season. Combined applications increased shoot length (39%) and branch count; in the most effective treatment, the branch count nearly doubled. The PEI increased by 60% in the early stages, and the leaf nutrient content (46.6%) and the colonisation of AMF in the soil were positively affected; thus demonstrating the synergistic effect of these biostimulants. The use of Trichoderma, AMF, and Bc can support sustainable pistachio production by improving growth, physiological performance, and nutrient status.
Mehmet Yılmaz, Ayhan Polat, Hasret Güneş· Folia Horticulturae· 0 citations
Hempseed press cake-derived protein hydrolysate (HPH) is a promising plant biostimulant, but its effects on strawberry fruit production under smart greenhouse conditions remain unclear. The objective of this study was to evaluate the effects of foliar HPH application on growth, mineral accumulation, reproductive traits, yield, fruit quality, and antioxidant properties of strawberry cv. ‘Pharachatan 80’. Plants were grown in a smart greenhouse and treated with water (control), a commercial biostimulant, and HPH at 7.5 and 10.0% (w/v) (HPH7.5 and HPH10.0, respectively). Foliar application was initiated 25 days after transplanting and repeated weekly for five applications. HPH applications showed clear concentration-specific improvements in vegetative growth, mineral accumulation, reproductive performance, fruit yield, and antioxidant quality. As the most effective treatment for overall crop performance, HPH7.5 enhanced plant growth and mineral accumulation, particularly K and Mg. Consequently, it improved both yield components (fruit set, number, weight, size, and total yield) and fruit quality attributes, such as total soluble solids, total phenolics, flavonoids, ascorbic acid, and ABTS radical-scavenging activity. Conversely, HPH10.0 was more closely associated with N, P, Ca, Fe, Zn, and Mn accumulation, as well as fruit firmness and total anthocyanin content, and DPPH radical-scavenging activity. Principal component analysis confirmed distinct response patterns between HPH concentrations. Thus, HPH7.5 serves as an effective foliar biostimulant to improve strawberry productivity and quality in smart greenhouses.