Agronomijas v stis - Latvijas Lauksaimniecības universitāte

16BM ean N o. of shoots/explant14121086420ABlueray Duke Berkeley Bluecrop BrigittaFigure 1. Effect of zeatin (A - 0.5 mg l -1 ; B - 2.0 mg l -1 ) on V. corymbosum L. shoot regeneration.The positive influence of zeatin on multiple shoot induction from apical and axillary buds wasconfirmed also in V. vitis-idaea cvs. Statistically significant differences in the number of shoots perexplant were obtained in cv. ‘Koralle‘ with the highest shoot formation on the zeatin concentrationof 0.75 mg l -1 . The differences between the control and the variants with different concentrations of2-iP were not statistically significant (Table 1.).Table 1. Multiple range analysis for shoot number/explant at different zeatin and 2-iPconcentrations in Vaccinium vitis-idaea L. - cvs. ‘Koralle’ and ‘Red Pearl’Zeatin Mean number of shoots/explantMean number of shoots/explant(mg l -1 2-iP (mg l -1 ))‘Koralle’ ‘Red Pearl’‘Koralle’ ‘Red Pearl’0.00 1.24 a 0.99 a 0.00 1.24 a 0.99 a0.25 3.00 ab 3.93 b 2.50 1.25 a 1.82 ab0.50 3.84 bc 5.02 bc 5.00 1.60 a 3.44 bcd0.75 5.19 c 5.55 bc 10.00 1.42 a 2.84 abc1.00 4.76 bc 6.98 c 15.00 1.27 a 6.66 e1.50 3.69 abc 6.90 c 17.50 1.16 a 5.47 de2.00 3.13 abc 6.20 bc 20.00 1.09 a 4.68 cdeIn cv. ‘Red Pearl’ the both tested cytokinins were effective in shoot regeneration. On the mediawith zeatin the highest shoot regeneration was obtained at the zeatin concentration 1.0 – 1.5 mg l -1 .The most effective 2iP concentration was 15 mg l -1 (Table 1.). Regeneration ability was differentfor each cultivar. The shoot proliferation per explant was higher in ´Red Pearl´ in comparison withcv. ´Koralle´ for both tested cytokinins.For induction of adventitious organogenesis on the leaf explants of V. corymbosum L. 0.5 mg l -1zeatin and 2.2 mg l -1 TDZ were used. On the media with TDZ callus formation was observed, butno adventitious buds were visible during the 5 weeks of cultivation. Shoot formation occurred onlyafter their transfer on medium with 0.5 mg.l -1 zeatin, which confirms the positive zeatin influenceon shoot regeneration. On the other hand, multiple adventitious shoots were formed after 5 weeksof cultivation on the leaf explants initially cultivated on an AN medium with 0.5 mg.l -1 zeatin,produced via direct regeneration. After the 3rd subculture on the same medium a high number ofvigorous shoots with good elongation growth was obtained per explant in the tested cultivars(Table 2.).77