Arbuscular mycorrhizal fungi increase grain yields: a meta‐analysis

Abstract

Increasing grain yields of food cereal crops is a major goal in future sustainable agriculture. We quantitatively analyzed the potential role of arbuscular mycorrhizal (AM) fungi in enhancing grain yields of seven cereal crops with exceptional importance for human nutrition across the globe: corn, wheat, rice, barley, sorghum, millet and oat.We conducted a meta-analysis for three datasets including both English and Chinese language publications: the 'whole' dataset including both laboratory and field studies (168 articles); the 'field' dataset comprising only field studies (97 studies); and the 'field-inoculation' dataset including only AM fungal inoculation studies conducted in field conditions (70 articles).We found that the AM fungal effect on grain yield was less pronounced in field and noninoculation studies. AM fungal inoculation in field led to a 16% increase (overall effect) based on the 'field-inoculation' dataset; this effect was variable (77% trials had positive values), crop-specific, lower for new cultivars released after 1950 and further modulated by soil pH.Although there are neutral and negative effects of AM fungi on grain yields, we emphasize the importance of integrating AM fungi in sustainable agriculture to increase grain yields of cereal crops.

Different wheat cultivars exhibit variable responses to inoculation with arbuscular mycorrhizal fungi from organic and conventional farms

“…It has been known that cultivars of wheat exhibit different responses to mycorrhizal fungal inoculation [11,12,19,20]. Although earlier studies found that older cultivars strongly responded to AM fungal inoculation, later studies provide mixed results [16,18,21]. This study found some support for older cultivar responding differently than recent cultivars.…”

“…A meta-analysis [21] showed no evidence that new wheat genotypes have lost their ability to respond to mycorrhizal fungi. On the other hand, a recent meta-analysis by Zhang et al [16] showed that there is a tendency of newer wheat varieties showing decreased response to AM fungi in terms of yield.…”

“…In addition, there have been several attempts to increase wheat nutrient uptake, growth and yield by applying extra AM fungal inoculum in the field. Meta-analyses have shown that AM fungal inoculation can increase aboveground biomass, grain yield, and P and N concentrations of wheat [15,16].…”

Seed Coating with Arbuscular Mycorrhizal Fungi for Improved Field Production of Chickpea

“…Despite the frequent demonstration of efficacy in laboratory and greenhouse experiments, the inconsistency of effectiveness or the lack of field data regarding AM fungi inoculation is still one of the main restraints for its wide application [22,50,51]. According to the meta-analysis of Zhang et al [52] there is a bias favoring controlled conditions for AM fungi inoculation; laboratory studies including inoculated crops tend to lead to higher grain yield increase in comparison with those studies carried out in the field. Surprisingly, our work contrasts these data as it shows that the positive effect of multiple AM fungi inoculation is maximized under field conditions.…”

Using variation in arbuscular mycorrhizal fungi to drive the productivity of the food security crop cassava

“… The unprecedented challenge to feed the rapidly growing human population can only be achieved with major changes in how we combine technology with agronomy 1 . Despite their potential few beneficial microbes have truly been demonstrated to significantly increase productivity of globally important crops in real farming conditions 2,3 . The way microbes are employed has largely ignored the successes of crop breeding where naturally occurring intraspecific variation of plants has been used to increase yields.…”