Implications of Below-Ground Allelopathic Interactions of Camelina sativa and Microorganisms for Phosphate Availability and Habitat Maintenance

Abstract

Toxic breakdown products of young Camelina sativa (L.) Crantz, glucosinolates can eliminate microorganisms in the soil. Since microorganisms are essential for phosphate cycling, only insensitive microorganisms with phosphate-solubilizing activity can improve C. sativa’s phosphate supply. In this study, 33P-labeled phosphate, inductively coupled plasma mass spectrometry and pot experiments unveiled that not only Trichoderma viride and Pseudomonas laurentiana used as phosphate-solubilizing inoculants, but also intrinsic soil microorganisms, including Penicillium aurantiogriseum, and the assemblies of root-colonizing microorganisms solubilized as well phosphate from apatite, trigger off competitive behavior between the organisms. Driving factors in the competitiveness are plant and microbial secondary metabolites, while glucosinolates of Camelina and their breakdown products are regarded as key compounds that inhibit the pathogen P. aurantiogriseum, but also seem to impede root colonization of T. viride. On the other hand, fungal diketopiperazine combined with glucosinolates is fatal to Camelina. The results may contribute to explain the contradictory effects of phosphate-solubilizing microorganisms when used as biofertilizers. Further studies will elucidate impacts of released secondary metabolites on coexisting microorganisms and plants under different environmental conditions.

Genetic study of Camelina sativa oilseed crop and selection of a new variety by the bulk method

“…However, these molecules play a role in plant defense mechanisms, and, as noted by Ghidoli et al. (2023b) , their occurrence can be attributed to the allelopathic properties inherent in camelina ( Quéro et al., 2016 ; Hofmann et al., 2023 ). A positive correlation (r = 0.69; p = 0.013) was observed between protein and glucosinolate content ( Figure 8 ), and the same result was obtained in the previous study ( Ghidoli et al., 2023c ), in which two hypotheses were proposed to explain the correlation.…”

Camelina sativa (L.) Crantz as a Promising Cover Crop Species with Allelopathic Potential

“…In addition, it has been estimated that in seed meal, depending on the accession, the GSL content can vary from 19.6 to 40.3 mmol kg −1 dry weight [68]. Therefore, it has been suggested that adult plants release GSLs into the environment mainly through root exudation or their decay [69], making the study of the root exudate dynamics and its chemical characterization a crucial step in exploiting the potential use of camelina as a cover crop, since the modulation through genetic improvement of their composition and release can strongly improve its effectiveness in weed control. Moreover, Quéro et al [70], studying the glucosinolate profile during seed development, observed that the buildup of glucosinolates primarily takes place within a timeframe of 15 to 25 days following the onset of flowering.…”