Larre atlantiarretako landareen sustraien atributuak (traits): lurzoruko ur-edukiaren eta mikrobiotaren eragina

Abstract

In the future, drought is expected to increase in intensity and duration due to the so reduced precipitation and high temperatures. This may lead to significant losses in crop production as well as its productivity worldwide. Research on the drought response of plant species is therefore urgently needed. This experiment has analysed the response to drought of six plant species of Atlantic grasslands, in the presence and absence of microorganisms, based on the root morphological traits. For this aim, a design has been implemented based on a split-plot design by randomised blocks in a greenhouse, where the plants in 5 blocks were maintained at a capacity of 30% of their water content (simulating drought) and those in the other 5 blocks at 70% (simulating normal conditions). In addition, two pots of the same species were placed in each block, adding the inoculum of the microorganisms to one and not to the other. One of the main hypotheses of the experiment is that under drought stress, plants can develop resource conservation or acquisition strategies by changing root traits. The second hypothesis is that the effect as well as the response of the microorganisms are dependent on the water content of the soil. The results indicate that both hypotheses were not fulfilled in this experiment. On the one hand, the effect of reduced soil water content was dependent of root traits and species, and considering these, the strategy followed by the plants was identified. On the other hand, reduced soil water availability did not affect the microorganisms. Furthermore, it has been analysed whether the effect of the microorganisms on each plant species has been positive or negative. It is concluded that the water content of 30% was not sufficient to simulate drought stress. Therefore, in the following experiments it is proposed to establish a soil water content of 10-20%, to maintain more days without watering and to establish non-optimal environmental conditions in the greenhouse.