Development and quality of melon fruits grown under salt stress¹

Desenvolvimento e qualidade de frutos de melão amarelo sob estresse salino

HIGHLIGHTS:

Irrigation water salinity reduces plant growth, but does not interfere with the fruit production of ‘Goldex’ yellow melon.

Irrigation with 4.0 dS m^-1 saline water does not impair the post-harvest quality of ‘Goldex’ melon fruits.

Total soluble solids is directly linked to fruit ripening stage and not to water salinity.

ABSTRACT

The need for studies that allow the use of brackish water in irrigated agriculture and the socioeconomic importance of melon cultivation in Brazil, especially for the Northeast region, which concentrates most of the national production and faces problems with the availability of good quality water for irrigation, motivated the present study. In this context, the objective of present study was to evaluate the growth, production and fruit quality of the ‘Goldex’ (yellow-type hybrid F1) melon under salt stress conditions. The experiment was performed in a completely randomized design, with two salinity levels of irrigation water (0.8 and 4.0 dS m^-1) and eight evaluation times (52, 54, 56, 58, 60, 62, 64, and 66 days after transplanting). Variables of plant growth and development, production and quality of melon fruits were evaluated throughout the cycle. Plants had delayed growth characteristics and less development with the increase in irrigation water salinity, showing reductions of more than 20% in shoot dry weight, leaf area, number of branches and length of secondary branches and 16.7% in length of the main branch. In addition, salinity caused a delay in fruit development and a 16% reduction in final fruit weight, without significantly modifying carbohydrate and total soluble solids contents. Along the development, there was an increase in the total soluble solids content of the fruits, especially due to the increment of sucrose at the final stages of development.

Key words:
growth inhibition; irrigation; salinity; post-harvest