Effect of spraying some growth regulators; salicylic acid; calcium and boron on yield and fruit quality of Barhee Date palms

Abstract EN

The present study was conducted during two successive seasons of ٢٠١٥ and ٢٠١٦ on ١٠-years-old Barhee date palms (Phoenix dactylifera L.) grown in sandy soil under drip irrigation system in a private orchard located at El-Saddat District, Menoufia Governorate, Egypt.

Bunches of the experimental palms were sprayed with six treatments as follows: water (control); gibberellin (GA٣) and Naphthalene acetic acid (NAA) (each at ٥٠, ١٠٠ and ٥٠ ppm); salicylic acid (at ٥٠, ٥٠ and ١٠٠ ppm) boric acid and calcium/boron, each at (٢٠٠٠, ١٥٠٠ and ١٠٠٠ ppm).

All the previous treatments were sprayed three times, the ١st was at one day before pollination, the ٢nd was at the beginning of kimri stage and the ٣rd was at the beginning of fruit color break (khalal or bisr stage), respectively.

All the spraying solutions were supplied with ٠.٢٥ % urea.

Generally, NAA and GA٣ treatments gained the highest value of each yield/palm; weight/bunch and number of fruits/spikelet without significant differences between them in most cases in both seasons.

While spraying catro calcium (calcium + boron) gained the highest value of each yield/palm and weight/spikelet in the two seasons compared to the control, which recorded the lowest value for each of all the tested characteristics in both seasons.

In addition, GA٣ and NAA treatments produced the highest value for each of all fruit physical characteristics without significant differences between them except for the fruit dimensions in the two seasons.

The highest seed weight was recorded for boric acid treatment in the two seasons, without significant difference with the control and salicylic acid treatments in the second season only.

Moreover, the control treatment gained the lowest value for each of all physical fruit characteristics except seed weight in the second season.

GA٣ and NAA treatments achieved the highest value of each TSS % and TSS/acid ratio and the lowest content of peel carotene in the two seasons.

While each of the control, boric acid and salicylic acid treatments recorded the highest percentage of fruit acidity in the two seasons.

The highest chlorophyll content in the fruit peel was recorded for salicylic acid treatment.