Benefits Conferred on Plants

It has long been known that under suboptimal conditions mycorrhized plants fare better than their non-mycorrhized counterparts. This applies to desert truffles as well: when conditions are less than favorable, plants that enter into mycorrhizal associations with desert truffles exhibit higher levels of transpiration, stomatal conductance, and photosynthesis. Furthermore, studies of the gene expression of a fungal aquaporin in the mycorrhizal state revealed negative correlations with plant physiological parameters, suggesting that there is some form of communication between the symbionts. In particular, fine-tuning of plant aquaporin gene expression is responsive to water availability. Consistent with results reported for other mycorrhizal fungi, mineral acquisition was higher in plants mycorrhized by desert truffles, as was photosynthesis. Girdling led to noticeable reduction in carbon assimilation in non-mycorrhized plants but only to a slight reduction in mycorrhized ones. In addition, not only was general chlorophyll content higher in plants forming associations with desert truffles, but the ratio of chlorophyll b to chlorophyll a was higher too, leading to improved light harvesting under the lower irradiance conditions typical of mornings and afternoons. Correspondingly, the calculated activation energy for onset of photosynthesis was lower for desert truffle-mycorrhized plants.