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ABSTRACT Sorghum (Sorghum bicolor) plays a critical role in global agriculture, serving as a staple food source and contributing significantly to various industries. However, sorghum cultivation faces significant challenges, particularly from pests like the sugarcane aphid (SCA), which can cause substantial damage to crops. In this study, we investigated the role of the caffeoyl coenzyme‐AO‐methyltransferase (CCoAOMT) gene in sorghum defense against SCA. Feeding by SCA induced the expression of theSbCCoAOMTgene, which is involved in the monolignol biosynthesis pathway. Aphid no‐choice and choice bioassays revealed thatSbCCoAOMToverexpression in sorghum resulted in reduced SCA reproduction and decreased aphid settling, respectively, compared to wild‐type (RTx430) plants. Furthermore, electrical penetration graph (EPG) studies revealed thatSbCCoAOMToverexpression restricts aphid feeding from the sieve elements. SCA feeding also induced the accumulation of lignin in sorghum wild‐type andSbCCoAOMToverexpression plants. Moreover, artificial diet aphid feeding bioassays with hydroxycinnamic acids, ferulic and sinapic acids, showed direct adverse effects on SCA reproduction. Our findings highlight the potential of genetic modification to enhance sorghum resistance to SCA and emphasize the importance of lignin‐related genes in plant defense mechanisms. This study offers valuable insights into developing aphid‐resistant sorghum varieties and suggests avenues for further research on enhancing plant defenses against biotic stresses.
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Interplay of Plasma Membrane and Vacuolar Ion Channels, Together with BAK1, Elicits Rapid Cytosolic Calcium Elevations in Arabidopsis during Aphid Feeding
A transient rise in cytosolic calcium ion concentration is one of the main signals used by plants in perception of their environment. The role of calcium in the detection of abiotic stress is well documented; however, its role during biotic interactions remains unclear. Here, we use a fluorescent calcium biosensor (GCaMP3) in combination with the green peach aphid (Myzus persicae) as a tool to study Arabidopsis thaliana calcium dynamics in vivo and in real time during a live biotic interaction. We demonstrate rapid and highly localized plant calcium elevations around the feeding sites of M. persicae, and by monitoring aphid feeding behavior electrophysiologically, we demonstrate that these elevations correlate with aphid probing of epidermal and mesophyll cells. Furthermore, we dissect the molecular mechanisms involved, showing that interplay between the plant defense coreceptor BRASSINOSTEROID INSENSITIVE-ASSOCIATED KINASE1 (BAK1), the plasma membrane ion channels GLUTAMATE RECEPTOR-LIKE 3.3 and 3.6 (GLR3.3 and GLR3.6), and the vacuolar ion channel TWO-PORE CHANNEL1 (TPC1) mediate these calcium elevations. Consequently, we identify a link between plant perception of biotic threats by BAK1, cellular calcium entry mediated by GLRs, and intracellular calcium release by TPC1 during a biologically relevant interaction.
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- PAR ID:
- 10045418
- Date Published:
- Journal Name:
- The Plant Cell
- Volume:
- 29
- Issue:
- 6
- ISSN:
- 1040-4651
- Page Range / eLocation ID:
- tpc.00136.2017
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1105/tpc.17.00136
