CsIVP Modulates Low Nitrogen and High-Temperature Resistance in Cucumber.

Crop plants experience various abiotic stresses that reduce yield and quality. Although several adaptative physiological and defense responses to single stress have been identified, the behavior and mechanisms of plant response to multiple stresses remain underexamined. Herein, we determined that the leaf and vascular changes in Cucumis sativus Irregular Vasculature Patterning (CsIVP)-RNAi cucumber plants can enhance resistance to nitrogen deficiency and high-temperature stress. CsIVP negatively regulated high nitrate affinity transporters (NRT2.1, NRT2.5) and reallocation transporters (NRT1.7, NRT1.9, NRT1.12) under low nitrogen stress. Furthermore, CsIVP-RNAi plants have high survival rate with low heat injury level under high-temperature condition. Several key high-temperature regulators, including Hsfs, Hsps, DREB2C, MBF1b and WRKY33 have significant expression in CsIVP-RNAi plants. CsIVP negatively mediated high-temperature responses by physically interacting with CsDREB2C. Altogether, these results indicated that CsIVP integrates innate programming of plant development, nutrient transport and high-temperature resistance, providing a potentially valuable target for breeding nutrient-efficient and heat-resistant crops.