The soil microbiome modulates the sorghum root metabolome and cellular traits with a concomitant reduction of Striga infection.

Sorghum bicolor is among the most important cereals globally and a staple crop for smallholder farmers in sub-Saharan Africa. Approximately 20% of sorghum yield is lost annually in Africa due to infestation with the root parasitic weed Striga hermonthica. Existing Striga management strategies are not singularly effective and integrated approaches are needed. Here, we demonstrate the functional potential of the soil microbiome to suppress Striga infection in sorghum. We associate this suppression with microbiome-mediated induction of root endodermal suberization and aerenchyma formation and with depletion of haustorium-inducing factors, compounds required for the initial stages of Striga infection. We further identify specific bacterial taxa that trigger the observed Striga-suppressive traits. Collectively, our study describes the importance of the soil microbiome in the early stages of root infection by Striga and pinpoints mechanisms of Striga suppression. These findings open avenues to broaden the effectiveness of integrated Striga management practices.

Fragile X Syndrome and Fetal Alcohol Syndrome: Occurrence of Dual Diagnosis in a Set of Triplets.

BACKGROUND: Fragile X syndrome (FXS) and fetal alcohol syndrome disorders are both common causes of intellectual disability in children. When both conditions are present in the same individual, the resultant phenotype may make identification of clinical issues and management challenging. CASE PRESENTATION: In this case report, we present a case of triplets who had significant in utero alcohol exposure; 2 of whom also have FXS and the other not having the fragile X mutation. The siblings with FXS have subtle differences in the physical phenotype compared with the other one, who has prominent features of partial fetal alcohol syndrome instead. However, all 3 siblings have intellectual impairment (although this is more severe in the 2 with FXS), meet diagnostic criteria for autism spectrum disorder, and present with severe behavioral challenges. The clinical presentation of the 2 siblings with FXS is much more severe as compared to a child with FXS alone, and this is likely due to the additive effect of in utero alcohol exposure and environmental factors. We discuss the combination of these 2 pathologies and how this can affect the overall clinical presentation. CONCLUSION: In the management of children with FXS, evaluation for other risk factors that can have neurobehavioral sequelae is important, and these can affect clinical presentation and prognosis.

Characterization of growth and development of sorghum genotypes with differential susceptibility to Striga hermonthica.

Two sorghum varieties, Shanqui Red (SQR) and SRN39, have distinct levels of susceptibility to the parasitic weed Striga hermonthica, which have been attributed to different strigolactone composition within their root exudates. Root exudates of the Striga-susceptible variety Shanqui Red (SQR) contain primarily 5-deoxystrigol, which has a high efficiency for inducing Striga germination. SRN39 roots primarily exude orobanchol, leading to reduced Striga germination and making this variety resistant to Striga. The structural diversity in exuded strigolactones is determined by a polymorphism in the LOW GERMINATION STIMULANT 1 (LGS1) locus. Yet, the genetic diversity between SQR and SRN39 is broad and has not been addressed in terms of growth and development. Here, we demonstrate additional differences between SQR and SRN39 by phenotypic and molecular characterization. A suite of genes related to metabolism was differentially expressed between SQR and SRN39. Increased levels of gibberellin precursors in SRN39 were accompanied by slower growth rate and developmental delay and we observed an overall increased SRN39 biomass. The slow-down in growth and differences in transcriptome profiles of SRN39 were strongly associated with plant age. Additionally, enhanced lateral root growth was observed in SRN39 and three additional genotypes exuding primarily orobanchol. In summary, we demonstrate that the differences between SQR and SRN39 reach further than the changes in strigolactone profile in the root exudate and translate into alterations in growth and development.