Arbuscular mycorrhizas increased tomato biomass and nutrition but did not affect local soil P availability or 16S bacterial community in the field

A response of biomass and nutrient allocation to the combined effects of soil nutrient, arbuscular mycorrhizal, and root-knot nematode in cherry tomato

Introduction

The biomass and nutrient allocation strategies in plants are fundamental for predicting carbon storage and mineral and nutrient cycles in terrestrial ecosystems. However, our knowledge regarding the effects of multiple environmental factors on biomass and nutrient allocation remains limited.

Methods

Here we manipulated soil composition (three levels), arbuscular mycorrhizal fungi inoculation (AMF, five levels), and root-knot nematode inoculation (RKN, two levels) using random block design to reveal the effects of these factors on biomass and nutrient allocation strategies of cherry tomato.

Results and Discussion

Our results showed that biomass and nutrient allocation were affected by soil composition, AMF and RKN individually or interactively. The biomass and nutrient allocation in cherry tomato shows different adaptation strategies responded to the joint action of three factors. The reduction of soil nutrients increased belowground biomass allocation, and aboveground nitrogen and phosphorus concentration. AMF colonization increased aboveground biomass allocation and reproductive investment and promoted aboveground nitrogen and phosphorus inputs. Cherry tomato can mitigate the stress of RKN infection by investing more biomass and nutrients into belowground organs. Our study showed that plants can adjust their survival strategies by changing biomass and nutrient allocation to adapt to variation in soil abiotic and biotic factors. These findings contribute to our understanding of the adaptive processes of plant biomass and nutrient allocation strategies under multiple environmental factors.

Arbuscular Mycorrhizal Fungi and Fertilization Influence Yield, Growth and Root Colonization of Different Tomato Genotype

Arbuscular mycorrhizal fungi (AMF) are beneficial for plant development and help absorb water and minerals from the soil. The symbiosis between these fungi and plant roots is extremely important and could limit crop dependence on fertilizers. The aim of this study was to evaluate the influence of AMF on tomatoes (Solanum lycopersicum L.), based on important agronomic traits of vegetative biomass, production, and fruits. The experiment was conducted in high tunnels, using 12 tomato genotypes under three different treatments: T1, control, without fertilizer and mycorrhizae colonization; T2, fertigation, without mycorrhizae colonization; and T3, arbuscular mycorrhizal fungi (AMF), seedling roots being inoculated with specialized soil-borne fungi. Plant growth, yield and fruit parameters indicated better results under mycorrhizal treatment. Root colonization with fungi varied significantly depending on the treatment and genotype, with a variation of 6.0-80.3% for frequency and 2.6-24.6% for intensity. For a majority of characteristics, the mycorrhization (T3) induced significant differences compared with the T1 and T2 treatments. In addition, AMF treatment induced a different response among the genotypes. Among the elements analyzed in the soil, significant differences were observed in phosphorous levels between planting the seedlings and after tomato harvesting and clearing of the plants. The results suggest that reducing fertilizers and promoting the symbiotic relationships of plants with soil microorganisms may have beneficial consequences for tomato crops.