Biometric, anatomical and physiological changes in passion fruit plants infected by cowpea aphid borne-mosaic virus

Cowpea aphid borne-mosaic virus (CABMV) is the causal agent of fruit hardening, an important disease that affects the development and productivity of passion fruit. The objective of this study was to evaluate biometric, leaf anatomical and physiological changes in passion fruit plants infected by CABMV. At 47 days after inoculation, healthy and CABMV-infected plants were evaluated for height, dry mass of stem, leaf and roots, leaf anatomy, gas exchange, total chlorophyll and carotenoid content, electrolyte extravasation, total soluble sugar content, starch, proline and total nitrogen. The height, dry mass of stem, leaves and roots, transpiration and photosynthetic rate were lower and the internal CO2 concentration was higher in plants infected by the virus. The thicknesses of palisade parenchyma, spongy parenchyma, mesophyll and leaf blade and the proportion occupied by palisade parenchyma were smaller in plants infected by CABMV. The starch content was lower and the total soluble sugar, proline and total nitrogen content were higher in plants infected by the virus. In passion fruit plants, CABMV infection causes leaf anatomical changes that corroborate its negative effect on photosynthetic rate, starch content and growth.