Abstract
ABSTRACT The aimed of this study was to evaluate the attenuating action of nitrogen doses on leaf cell membrane damage, dry biomass production and leaf area in the formation of yellow passion fruit seedlings irrigated with saline water. Treatments were arranged in a randomized block design, in split plots, corresponding to five levels of irrigation water salinity (plot) (ECw) (0.3; 1.0; 1.7; 2.4 and 3.1 dS m-1) and five doses of nitrogen fertilization (subplot) (60; 80; 100; 120 and 140% of 300 mg of N dm-3), which were repeated in five blocks. Plants were grown in pots (Citropote®) with a volume of 3,780 mL, which were filled with a mixture of soil, aged bovine manure and sawmill residue (shaving) in a ratio of 2:1:0.5, respectively. Waters with different levels of salinity were applied from 40 to 85 days after sowing, when the plants were in transplanting conditions. At 85 days after sowing, the percentage of cell damage based on electrolyte leakage, variables of dry biomass, leaf area and specific leaf area were evaluated. Increment in irrigation water salinity reduces the biomass accumulation of yellow passion fruit seedlings; The increase in nitrogen dose did not mitigate the effect of salinity, which reduced cell membrane integrity, making the plant more sensitive.
Highlights
Yellow passion fruit (Passiflora edulis Sims f. flavicarpa DEG.), known as sour passion fruit, is a highly widespread species in Brazil, with production of 602,651 tons in an area of 42,731 ha, and the largest producers are the states of Bahia, Ceará, Santa Catarina, São Paulo, with Bahia being responsible for 26.9% of Brazilian passion fruit production (IBGE, 2017)
Water salinity significantly affected cell membrane damage (%D) as well as total dry mass (TDM) and stem dry mass (StDM), which was significantly affected by N levels
Increase in nitrogen dose did not mitigate the effect of salinity, which reduced the cell membrane integrity, making the plant more sensitive
Summary
Yellow passion fruit (Passiflora edulis Sims f. flavicarpa DEG.), known as sour passion fruit, is a highly widespread species in Brazil, with production of 602,651 tons in an area of 42,731 ha, and the largest producers are the states of Bahia, Ceará, Santa Catarina, São Paulo, with Bahia being responsible for 26.9% of Brazilian passion fruit production (IBGE, 2017).it is evident the potential of the Northeast region for the production of this crop, which is related to the favorable edaphoclimatic conditions, except for rainfall, which is lower than evapotranspiration, causing water deficit to plants (CAVALCANTE et al, 2002; FREIRE et al, 2014), making it necessary to use irrigation in order to ensure satisfactory levels of passion fruit yield.besides the low availability of water and the need to perform irrigation, in most cases the waters have high contents of dissolved salts (CAVALCANTE et al, 2002), which can induce physiological changes and compromise the development and production of the crop, which is considered sensitive to soil and water salinity.The most striking effects of salinity on plants are changes in osmotic potential, ionic toxicity and imbalance in the absorption of nutrients, causing a generalized reduction in their growth (AHMED; MORITANI, 2010; SOUSA; BEZERRA; FARIAS, 2010).According to Silva et al (2014) and Lima et al (2015), excess salts in irrigation water can cause changes in the permeability of cell membranes and in the physiological and biochemical functions of plants, leading to osmotic stress, which results in disorders in water relations, changes in the absorption and use of essential nutrients, as well as the accumulation of toxic ions (Na+ and/or Cl-) in chloroplasts, regardless of the nature of the salts.On the other hand, as salinity can cause osmotic and ionic effects, the stimulus to the production of osmoprotective amino acids, carbohydrates and proteins is compromised, and proline is a stress-related metabolite that aids in osmoregulation and favors the increase in the tolerance to certain levels of water and salt stresses (SALAZAR et al, 2017). Flavicarpa DEG.), known as sour passion fruit, is a highly widespread species in Brazil, with production of 602,651 tons in an area of 42,731 ha, and the largest producers are the states of Bahia, Ceará, Santa Catarina, São Paulo, with Bahia being responsible for 26.9% of Brazilian passion fruit production (IBGE, 2017) It is evident the potential of the Northeast region for the production of this crop, which is related to the favorable edaphoclimatic conditions, except for rainfall, which is lower than evapotranspiration, causing water deficit to plants (CAVALCANTE et al, 2002; FREIRE et al, 2014), making it necessary to use irrigation in order to ensure satisfactory levels of passion fruit yield. It is known that nitrogen (N) is an element that participates in the formation of several compounds considered indispensable, such as amino acids, proteins, nucleic acids and chlorophylls (TAIZ et al, 2017)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
