ARI Biennial Review for 2018-2019

Diversity of mycorrhiza in different crops and plant breeding The symbiosis of cultivated plants with functional soil microbial guilds is extremely important for agroecosystem productivity, especially in low-input agricultural systems. In this study, we evaluated the abundance and the diversity of mycorrhizal fungi in different underutilised cereals, maize, chickpeas and faba beans. The results showed not only differences between plant species regarding their colonisation with mycorrhizal fungi, but significant differences were also observed between the different genotypes within the same plant species. Genotypes showing higher colonisation and greater diversity of mycorrhizal fungi in their root system are of interest for plant breeding to treat abiotic stresses. The study is funded by the European Union in the context of the Horizon2020 project under the acronym “DIVERSIFOOD” (2015-2019). ( M. Omirou, D. Fasoula, I.M. Ioannides ) Impact of soil water availability and genotype on mycorrhiza diversity of chickpea Chickpea is one of the most important legumes in the world and could be dramatically affected from water limitation. Chickpea is associated with arbuscular mycorrhizal fungi (AMF) that are known for their contribution to the alleviation of drought stress in plants. In the current study, we evaluated the effect of water limitation in two chickpea genotypes (A345 and A365) and how water limitation affected plant performance and AMF symbiosis (composition and colonisation), in a microcosm study using a complete randomized design. Water limitation had a detrimental effect only in A345 genotype performance, and this was depended on plant growth stage. On the contrary, the biomass production of A365 genotype was not affected from water limitation 55 days after the initiation of the experiment. This response was associated with AMF colonisation. The colonisation found in the sensitive to water limitation genotype A345 was substantially suppressed in both growth stages while the colonisation of the tolerant, A365 genotype was not affected under drought stress conditions. Multivariate analysis showed that the composition of AMF communities in chickpea was significantly affected by the interaction between growth stage, genotype and water availability (p < 0.01). Differential abundance analyses showed that the abundance of specific AMF genera in the tolerant to water limitation genotype A365 was substantially decreased at early growth stages compared to the sensitive genotype A345. These findings highlight that A365 could be less depended on mycorrhizal presence and/or that the AMF colonisers are more efficient acting complementary to the plant inherent drought tolerant mechanisms to alleviate water shortage ( M. Omirou, D. Fasoula, I.M. Ioannides ) 66 AGROBIOTECHNOLOGY