Stimulation of node and lateral shoot formation in micropropagation of olive (Olea europaea L.) by using dikegulac

Abstract

Dikegulac, a growth regulator, was shown to stimulate in vitro shoot multiplication of olive cultivars Canino, Frantoio, Moraiolo, but not cultivars Rosciola and Piantone di Moiano. The Rugini Olive Medium including zeatin (4.5 lM) was used supplemented with a range of dikegulac concentrations (0-133.4 lM). An optimal result in number of shoots and nodes was obtained on cultivars Canino, Frantoio and Moraiolo at 66.7 lM dikegulac. Higher concentrations did not stimulate additional shoot and node formation and resulted in a drastic reduction in height of shoots. Elongated shoots were rooted and acclimatised and showed normal development compared to control plants.

EFFECT OF EXOGENOUS DIKEGULAC ON IN VITRO SHOOT PROLIFERATION OF Sideritis raeseri L. � GREEK MOUNTAIN TEA SPECIES

“…Spreng. Similar explanation was proposed in olives, where 66.7 and 100.5 μM DS in the cultivars Canino and Moraiolo and 33.8-100.5 μM in Frantoio cultivar increased the number of shoots/explant (Mendoza de Gyves et al, 2008). On the other hand, a reduced number of shoots was reported for the in vitro culture of Vaccinium corymbosum L. cv 'Herbert' when DS combined with 5 mg/l 2-isopentenyladenine (2ip) (Litwińczuk and Prokop, 2010 In Sideritis raeseri L., DS regardless its concentration (10-1500 μM) did not influence shoot length in a considerable degree (12.48-16.11 mm) (Table 1).…”

“…In a previous study conducted by Sarropoulou et al (2014) in the cherry rootstock CAB-6P (Prunus cerasus L.), DS when applied at 120 μM or 150 μM concentrations diminished shoot length considerably. In addition, Mendoza de Gyves et al (2008) reported that DS (100.5 and 133.4 μM) had a negative effect on shoot length in the olive cultivars Canino, Frantoio and Moraiolo. According to Thetford and Berry (2000), DS exerted an inhibitory effect on height in euonymus, forsythia, Chinese privet, waxleaf privet and azalea.…”

“…Furthermore, DS was shown to stimulate in vitro shoot multiplication of the olive cultivars Canino, Frantoio and Moraiolo but not of the cultivars Rosciola and Plantone di Moraiolo. An optimum number of olive shoots was obtained with 66.7 μM DS (Mendoza de Gyves et al, 2008). DS is transported from the leaves to the apex in very small quantities and affects only certain cell types (Arzee et al, 1977).…”

“…Very few reports exist in the literature concerning the use of DS in in vitro propagation (Mendoza de Gyves et al, 2008). In Zantedeschia aethiopica (calla lilly), Ebrahim (2004) noted an increase in shoot multiplication rate by increasing the DS concentration up to a certain value, above of which shoot number was similar to the control.…”

Neem Oil Used as a “Complex Mixture” to Improve In Vitro Shoot Proliferation in Olive

“…Such failure is mainly due to the different behavior of the various cultivars, which requires setting up a specific protocol for each variety (Bahrami et al, 2010;Lambardi and Rugini, 2003;Rostami and Shahsavar, 2012), and the use of zeatin, which is very expensive (Mendozade Gyves et al, 2008). To solve or reduce these problems, efforts have been made to identify alternative cytokinins or compounds/ protocols able to improve the regeneration efficiency of the explants to reduce the unit cost of regenerated shoots (Ali et al, 2009;Mendoza-de Gyves et al, 2008).…”