Impact of saline water irrigation on the growth and development of coconut (Cocos nucifera L.) seedlings

Coconut (Cocos nucifera L.), a perennial fruit and oil crop, holds significant economic importance globally. Its inherent high salt tolerance has led to natural adaptation in coastal environmental areas. Nevertheless, the substantial and prolonged intrusion of salinity poses a severe threat to the growth and productivity of coconut in various regions of Vietnam. Thus, the objectives of this study were to determine the effect of saline water on the growth and biomass of coconut seedlings named Dua Ta variety under green house condition. The experiment was carried out from July 2022 to July 2023 in a greenhouse condition at Research Institute for Oil and Oil Plants, Vietnam with five increasing levels of water salinity, or EC of 0.89, 6.25, 12.0, 18.25 and 24.5 dS/m. Various growth parameters and biomass of the coconut seedlings were investigated. The results showed that the salinity of irrigated water had a negative effect on the growth and biomass of coconut seeldings. Increasing salinity of irrigated water delined the plant height, collar girth, leaf number and biomass of the coconut seedlings. The seedling of Dua Ta coconut was classified as tolerant when irrigated with saline water of 6.25 dS/m, moderately sensitive with saline water of 12.0 dS/m up to 18.25 dS/m and sensitive with saline water of 24.5 dS/m. As result, it is showing evidence of ecological adaptation of the seedlings of Dua Ta to the maritime environment in which are commonly grown in Vietnam.