Salinity-induced changes in biometric, physiological and anatomical parameters of Passiflora edulis Sims plants propagated by different methods

ABSTRACT

Salinity is one of the most important abiotic stresses limiting agricultural production worldwide. Here, we investigated the biometric, physiological and anatomical changes of Passiflora edulis plants propagated from seeds, cuttings and grafts and exposed to salt stress (0.3 – control and 6.3 dS m⁻¹). Saline stress significantly reduced plant height, the number of leaves, total chlorophyll, stomatal conductance, shoot dry weight, total dry weight, total water consumption and root volume. Among the propagation methods evaluated, plants propagated from seeds were more sensitive to salinity, while plants propagated from cuttings showed smaller alterations when subjected to salinity. Similar behavior was observed for anatomical characteristics, since plants propagated from seeds presented more pronounced anatomical alterations, such as greater thicknesses of the leaf mesophyll, upper epidermis, lower epidermis, palisade parenchyma and spongy parenchyma and also was observed presence of calcium oxalate crystals in the form of druses in greater quantity in the root cortex, in comparison to plants propagated from cuttings. The approach used in this study allowed identifying the type of yellow passion fruit propagation (cuttings) that was best for physiological and anatomical adaptation to salt stress and will be potentially useful in programs for improvement of the crop.

KEYWORDS:

• Passion fruit
• propagation
• stomatal conductance
• anatomy
• saline stress

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors thank the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for the award of doctoral scholarship to the first author (R.S.M.) and for the post-doctoral scholarship grant (PNPD 15950830814) given to the second author (T.L.S.), to Conselho Nacional de Ciência e Tecnologia (CNPq) for financial support (MACF Process 311327/2015-0; 421033/2018-5) and for post-doctoral scholarship (PDJ151086/2018-4) given to the third author (L.K.S.L.) and also for the research productivity fellowship given to the fifth (PQ312774/2018-4) and sixth (PQ303912/2018-9) authors . We also thank the Embrapa Mandioca e Fruticultura for providing plant materials, experimental and for technical and financial support (MP 22.16.04.007.00.00).