Arbuscular mycorrhizal fungi in oat-pea intercropping

Abstract

Arbuscular mycorrhizal fungal diversity can be altered by intercropping plant species, as well as N fertilizer applications. This study examined the effects of oat-pea intercropping and N fertilizer addition on the richness and diversity of mycorrhizal species, as well as identified the most common arbuscular mycorrhizal fungi (AMF) genera recruited for oats and peas in two growing seasons (2019 and 2020). The AMF diversity was higher in an intercropped system compared to their respective monocropping system. Under drier conditions in 2019, arbuscular mycorrhizal richness decreased with N fertilizer addition in sole peas and increased with N fertilizer addition in sole oats, but no significant change in richness was observed in oat-pea intercropping. During the wetter growing season 2020, arbuscular mycorrhizal diversity increased when oat and pea were intercropped, compared to either sole oat or sole pea. Diversispora in sole pea was a significant indicator differentiating the root associated AMF community from sole oat. Claroideoglomus richness increased in peas in 2020, thus this genus could be moisture dependent. Paraglomus richness in oat-pea intercropping was similar to sole oat in 2019, and similar to sole pea in 2020. This can suggest that Paraglomus is an indicator of plant stress under intercropping, as based on the premise that stressed plants release more exudates, and the subsequent mycorrhizal associations favor these plants with higher exudation. Future investigations can further reveal the functions and benefits of these mycorrhizal genera in annual monocrop and intercropping systems.

Alternatives Cover Crops and Soil Managements Modified Macronutrients, Enzymes Activities and Soil Microbial Diversity in Rainfed Olive Orchards (cv.Chétoui) under Mediterranean Conditions in Tunisia

“…Nitrogen content in aboveground biomass reached values close to 90, 40 and 10 kg N.ha -1 in legumes, fertilized natural vegetation and non-fertilized natural vegetation respectively [35]. [41] found out that Faba bean and Rye-Vetch produced 105 kg.ha -1 and 89.3 kg.ha -1 respectively. In our study, legumes species and mixed recorded high values of N fixed by dry biomass, mainly for the Fenugreek crop for which N content varied between 100 and 400 kg.ha -1 .…”

Alternative Cover Crops and Soil Management Practices Modified the Macronutrients, Enzymes Activities, and Soil Microbial Diversity of Rainfed Olive Orchards (cv. Chetoui) under Mediterranean Conditions in Tunisia

“…The availabilities of soil macronutrients in the top soil layer were the result of organic matter decomposition. During the 2021 and 2022 cropping seasons, the soil N with cover crops increased compared to that of a control [16,44] with no significant differences between species or the dry biomass incorporated into the soil. The values were still in the range of soil N limits.…”

“…In addition, the biomass produced by the different cover crop species tested can be cut and used as feed for animal production, increasing the olive ecosystem's profitability and services, as well as the incomes of farmers. In this case, only residues are incorporated into the soil and serve as bio-fertilizers [44,45]. The carbon rate fixed by the cover crops was closely related to the respective dry biomass produced.…”