The Role of Ethylene in the Regulation of Fruit Ripening in the Hillawi Date Palm (Phoenix dactyliferaL)

Abstract

The role of ethylene in the regulation of fruit ripening in the date palm (Phoenix dactyliferaL) was investigated. It was found that the rate of CO2 output was high initially, but the rate declined steadily as the fruit advanced in maturity, reaching its lowest level as the fruit entered the stage of physiological maturity, but then the rate of respiration increased as the fruit entered the ripening phase, reached a peak value and then declined. Ethylene emission was not detected until the 91st day from pollination when ethylene production began with a rapid increase in emission, reaching a peak value within 15 days and then declining rapidly. The peak of ethylene production preceded the climacteric peak by 7 days.

Respiration rate, ethylene production and biochemical changes during fruit development and maturation of jujube (Ziziphus mauritiana Lamk)

“…9 Changes in chemical composition, ie total soluble solids, titratable acidity, protein and sugars (invertase was inactivated by plunging the fresh samples into boiling ethanol during preliminary extraction), were measured using the methods of the AOAC, 10 unless stated otherwise. A completely randomised design was used with four replicates (each replicate consisted of at least 30-50 fruits, depending on the stage of maturity).…”

“…17 However, for date palm fruit (Phoenix dactylifera L) it was found that the peak of ethylene production preceded the climacteric peak by 7 days. 9 During the second period of rapid growth the rate of respiration increased sevenfold, whilst the rate of ethylene production increased 47-fold. The rate of ethylene production by ripe jujube fruit cv Zaytoni is considered very high according to the classification of Kader and Kasmire.…”

Date ( Phoenix dactylifera L.)

“…The normal date palm fruit is a berry which results from the ovary (Mater, 1991). After pollination and fertilization, fruit growth follows a sigmoidal curve, and is usually divided into fi ve stages of development known by their Arabic terms: 'hababouk', 'kimri' (kimri, jimri), 'khalal' (balah, bisr), 'rutab' and 'tamr' (tamar) ( Figure 4.2 ) (Abbas and Ibrahim, 1996;Ait-Oubahou and Yahia, 1999;Yahia, 2004). The 'hababouk' stage starts after fertilization and is characterized by the loss of two unfertilized carpels.…”

“…Cured Deglet Noor dates with 20-22% moisture produced 0.4 mg CO 2 kg −1 h −1 at 24°C, and 2 mg CO 2 kg −1 h −1 when the moisture content increased to 27% (Rygg, 1975). The rate of CO 2 production is high initially, but declines steadily as the fruit advances in maturity, reaching its lowest level as the fruit enters the stage of physiological maturity, and then increases to reach a peak as the fruit ripens (Abbas and Ibrahim, 1996). Rouhani and Bassiri (1976) found that the respiration rate of Shahani dates was high during the early stages of fruit development and decreased sharply as the fruit entered the ripening phase.…”

“…Ethylene production in Hallawi dates was not detected until 91 days after pollination, increased to reach a peak within 15 days and then declined rapidly (Abbas and Ibrahim, 1996). There is no effect of exposing khalal stage, yellow Barhee dates to 100 ppm ethylene for up to 48 hours at 20°C and 85-90% RH (Ait-Oubahou and Yahia, 1999).…”