BvCaM7 Participates in Sugar Beet (Beta vulgaris L.) Resistance to CLS (Cercospora Leaf Spot) by Activating BvPAL via BvMYB108 and Is Accompanied by Calcium Dynamics.

BvCaM7 is significantly upregulated in sugar beet (Beta vulgaris L.) under Cercospora leaf spot and is linked to enhanced PAL-driven lignin-related defense.

• Why it matters: CLS is a major constraint in sugar beet cultivation, but CaM/CML family roles in CLS resistance remain unclear, limiting targeted breeding.
• What they did: The CaM/CML family was identified and BvCaM7 was tested; it interacts with BvCNGC14 and BvMYB108, while BvMYB108 activates the PAL promoter and coexpression with BvCaM7 enhances this effect.
• The result: Transient overexpression of BvCaM7 or BvMYB108 in tobacco reduced lesion development after Cercospora beticola inoculation, with BvMYB108 peaking at 12 h and BvCaM7 sustaining expression until 24 h, alongside altered SOD/POD/CAT activities and calcium dynamics.