Arbuscular Mycorrhizal Fungi and Plant Growth-Promoting Rhizobacteria Enhance Soil Key Enzymes, Plant Growth, Seed Yield, and Qualitative Attributes of Guar

Abstract

Guar is an economically important legume crop that is used for gum production. The clean and sustainable production of guar, especially in newly reclaimed lands, requires biofertilizers that can reduce the use of mineral fertilizers, which have harmful effects on human health and the environment. The present study was conducted to investigate the effects of biofertilizers produced from Bradyrhizobium sp., Bacillus subtilis, and arbuscular mycorrhizal fungi (AMF), individually or in combinations, on microbial activity, and nutrients of the soils and the guar growth and seed quality and yield. The application of biofertilizers improved shoot length, root length, number of branches, plant dry weight, leaf area index (LAI), chlorophyll content, and nutrient uptake of guar plants compared with the control plants. Moreover, the application with biofertilizers resulted in an obvious increase in seed yield and has improved the total proteins, carbohydrates, fats, starch, and guaran contents in the seeds. Additionally, biofertilizer treatments have improved the soil microbial activity by increasing dehydrogenase, phosphatase, protease, and invertase enzymes. Soil inoculation with the optimized doses of biofertilizers saved about 25% of the chemical fertilizers required for the entire guar growth stages. Our results could serve as a practical strategy for further research into integrated plant-microbe interaction in agriculture.

Arbuscular Mycorrhizae Mitigate Aluminum Toxicity and Regulate Proline Metabolism in Plants Grown in Acidic Soil

“…The interaction between AMF and plants can enrich soil resources with essential nutrients that help plants to effectively respond to different environmental factors [ 56 ]. Several studies have reported the effects of environmental factors on the effectiveness of AMF in improvement of plant growth [ 29 ]; since AMF are attached to plant roots, they receive a lower amount of photosynthates under Al stress. The present study reported that mycorrhizal growth markedly decreased in lotus compared with barley under Al stress ( Table 1 ), demonstrating that the impact of Al levels on mycorrhizal growth seems to be dependent on the plant species.…”

“…In this regard, AMF are effectively used to enhance the biological nitrogen fixation and phosphate solubilization processes in soil and the rhizosphere [ 75 ]. In addition, mycorrhizal inoculation significantly enhanced dehydrogenase activity, which could be attributed to the ability of AMF to improve the physical and chemical properties of soil, especially the soil structure, enhancing the organic matter decomposition and remobilizing nutrients, including nitrogen, in the rhizosphere and soil [ 29 ]. Due to the close connection between Pro and N metabolism [ 68 ], enhanced N uptake could enhance Pro accumulation Pro [ 69 , 70 ].…”

“…For AMF treatment, the AMF spores used were Rhizophagus irregularis MUCL 41833; these were obtained from the in vitro collection of Glomeromycota (GINCO) ( accessed on 2 February 2021). The inoculants of AMF were prepared using the methodology of El-Sawah et al [ 29 ]. Briefly, AMF spores were grown for 6 months on the roots of Sorghum sudanenses Pers., and 5 g of trapped soil per plant or per pot (approx.…”

Inoculation with Bacillus amyloliquefaciens and mycorrhiza confers tolerance to drought stress and improve seed yield and quality of soybean plant

“…A study by Masciarelli et al (2014) Arbuscular mycorrhizal fungi (AMF) are also able to promote plant nutrients and water uptake as well as increase resistance to several abiotic stresses, especially drought and salinity (Cely et al, 2016;Rathod et al, 2011;Sun et al, 2018). AMF inoculation techniques have been applied in field trials to increase the quantitative and qualitative traits of several field crops (Cely et al, 2016;El-Sawah et al, 2021;Gao et al, 2020). Gholamhoseini et al (2013) reported that AMF symbiosis can alleviate drought stress and increase root size, leaf area, and plant biomass under immediate drought conditions.…”

Effect of Source–Sink Ratio Manipulation on Growth, Flowering, and Yield Potential of Soybean

“…Two field experiments were conducted during the 2018 and 2019 growing seasons at the Agronomy Farm of Mansoura University, Egypt, from May to November. The meteorological data and the soil properties of the study area were described in our previous studies [29,30]. The experimental plots comprised four ridges of 3.5 m in length; the spacing between ridges was 70 cm and between hills was 25 cm.…”