Impact of preharvest foliar spray chitosan, nano-chitosan, and calcium chloride treatments on some fruit chemical characteristics of 'barhi' date palm fruits during cold storage

الملخص EN

"Barhi" fruits obtained from, 11 years old date palm plants are grown on a private farm (Pico) at Masr-Alexandria desert road, Egypt.

Date palm fruits were harvested at the Khalal stage when fruits attained full color (bright yellow)in mid-September during the 2019 and 2020 experimental seasons (one month before treatments).

Fruits were delivered to a packing house on the same farm.

Fruits that showed no symptoms of mechanical damage or degradation were chosen and standardized to ensure uniform size, color, and form, before being randomly assigned to one of ten groups.

The goal of this study was to see how chitosan, Nano-Chitosan, and calcium chloride, used individually as safe pre-harvest treatments with different concentrations, affected some physicochemical aspects of "Barhi" date palm fruits to retain quality during cold storage and lengthen post-harvest life.

Anyhow, the used pre-harvest treatments were: Control (Water only), Chitosan 1, 2 and 3 g/L, CaCl₂ 1, 2 and 3g/L, Nano-Chitosan 1, 2 and 3 cm³ /L.

all the treatments were added sprinkles every two weeks (two times pre-harvest) during the period from 15 August to 15 September (harvest time).

Taking into consideration that sprays treatments were applied covering the whole bunch, whereas 2 liters was found to be sufficient in this concern.

All treatments were very effective for improving fruit quality in terms of increasing (total soluble solids % , total sugars, total acidity % , TSS/acid ratio, and total soluble tannins) as compared with the control treatment.

The best results concerning fruit quality and storability of Barhi date palms were obtained with the treatments Nano-Chitosan 3 cm³ /L.

or CaCl₂ 3g/L.