Comprehensive Analysis of Highbush Blueberry Plants Propagated In Vitro and Conventionally

Abstract

In vitro culture allows the production of numerous plants with both desirable and undesirable traits. To investigate the impact of the propagation method on highbush blueberry plants, an analysis was performed on four groups of differentially propagated plants: in vitro with axillary (TC-Ax) or adventitious shoots (TC-Ad), conventionally (SC) and using a mixed method (TC/SC). The analysis included plant features (shoot length and branching, chlorophyll and fluorescence and DNA methylation) and fruit properties (antioxidant compounds). The data obtained indicated significant differences between plants propagated conventionally and in vitro, as well as variations among plants derived from in vitro cultures with different types of explants. SC plants generally exhibited the lowest values of morphological and physiological parameters but produced fruits richest in antioxidant compounds. TC/SC plants were dominant in length, branching and fluorescence. Conversely, TC-Ax plants produced fruits with the lowest levels of antioxidant compounds. The methylation-sensitive amplified polymorphism (MSAP) technique was employed to detect molecular differences. TC-Ad plants showed the highest methylation level, whereas SC plants had the lowest. The overall methylation level varied among differentially propagated plants. It can be speculated that the differences among the analysed plants may be attributed to variations in DNA methylation.

Keywords: DNA methylation; Vaccinium sp.; antioxidant; plant in vitro culture; somaclonal variation.

Figure 1

Fluorescence parameters. The mean value marked with different lowercase letters differs significantly at p ≤ 0.05.

Figure 2

Chlorophyll content. The mean value of chlorophyll marked with different lowercase letters differs significantly at p ≤ 0.05.

Figure 3

Results of antioxidant activity. The mean value marked with different lowercase letters differs significantly at p ≤ 0.05.

Figure 4

Total anthocyanins and total polyphenol contents. The mean value marked with different lowercase letters differs significantly at p ≤ 0.05.

Figure 5

Ascorbic acid content. The mean value marked with different lowercase letters differs significantly at p ≤ 0.05.

Figure 6

Differences in DNA band patterns—products of selective amplification as part of MSAP analysis. Red arrows indicate the lack of specific DNA bands for in vitro-derived plants (TC-Ax and TC-Ad) (A) or for TC-Ax plants only (B,C).