| Popis: |
The capacity of Jasmonic acid (JA) to improve in vitro multiplication phase in micropropagated shoots of low vigorous pear and cherry rootstocks – Pyrodwarf and Gisela 6 respectively, was studied. The experiment was performed during the multiplication phase and it included 23 media types containing Murashige and Skoog (1962) macro, micro salts and organic complex supplemented with JA at four concentrations (1, 2.3, 5 and 10 µM) alone and in combination with benzyl adenine – BA (4.4 µM), indole-3-butyric acid – IBA (1, 2.30, 2.46, 5 and 10 µM), α-napthyl acetic acid –NAA (1, 2.30, 2.68, 5, 10 µM), and indole-3-acetic acid – IAA (1, 2.30, 2.85, 5, 10 µM). The multiplication parameters, such as multiplication index, length of axial and lateral shoots, FW and DW of shoots as well as quality of multiplied shoots were monitored. The highest multiplication rate in both genotypes was obtained on medium with BA (4.4 µM) in combination with IBA (1 and 2.3 µM). The longest axial and lateral shoots were also obtained on media with BA in combination with JA or other three auxins used. The main characteristics of the JA effect (used alone) were big shoots, large green leaves, small quantity of firm, nodular callus as well as occurrence of rooting. The obtained results suggest that JA used alone should not be used to improve the multiplication process, but only in combination with BA and IBA or NAA for the high quality plantlets which is important for the rooting phase, to skip elongation phase. |
