The Evaluation of Different Plum and Pear Rootstocks in the Nursery

Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences.

et al. 2019

The issue of the influence of rootstock on winter-hardiness of plum (Prunus × rossica Erem.) tree flower buds in the Baltic region is becoming important. The choice of rootstock is the main precondition for obtaining a high yielding and sustainable plum orchard. Freezing of flower buds is one of the most significant damages in winter for stone fruits. The aim of the investigation was to determine the relationship between concentration of dry matter and reducing sugars in annual shoots during winter and wintering ability of trees. The dynamics of reducing sugar concentration in one-year-old shoots during winter was investigated during two successive seasons in two locations. Orchards were planted in 2001 in Latvia and in Estonia. The well-known plum cultivar ‘Kubanskaya Kometa’ (Prunus rossica Erem.) was grafted on eight clonal rootstocks (‘St. Julien A’, ‘Brompton’, ‘Ackermann’, ‘Pixy’, GF8/1, G5/22, GF655/2, and ‘Hamyra’) and eight generative propagated rootstocks (‘St. Julien INRA 2’, ‘St. Julien d’Orleans’, ‘St. Julien Noir’, ‘Brompton’, ‘Wangenheims Zwetsche’, ‘St. Julien Wädenswill’, ‘Myrobalan’ and Prunus cerasifera var. divaricate). Shoot samples were harvested two times during winter — at the end of January and at the end of March. Dry matter concentration (mg·g−1) and the concentration of reducing sugars (mg·g−1 DM) by Fehling’s solution method was determined. Tree flowering intensity was scored using a scale from 1 to 5, where 1 = no flowers and 5 = abundant flowering. Dry matter concentration in plum shoots varied among rootstocks, years and growing location. In Pūre, Latvia, the largest differences in dry matter concentration were found for trees grafted on ‘St. Julien INRA2’ (in 2011–2012) and ‘Brompton’ cuttings (in 2012–2013) but in Polli, Estonia for trees grafted on G5/22 (in 2011–2012) and ‘Myrobalan’ (in 2012–2013). One of the most stable rootstock/graft combinations in the trial when GF655/2 was used as rootstock, where dry matter concentration was between 491 and 525 mg·g−1, and reducing sugars between 37.5–49.2 mg·g−1, and flowering intensity between 2.5 and 4.

Section: Introductionmentioning

confidence: 99%

Influence of Plum Rootstock on Flowering Intensity Depending on Concentration of Dry Matter and Reducing Sugars in Annual Shoots

Dēķena

Lepsis

Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences.

et al. 2019

“…Caucasian plum (Prunus cerasifera Ehrh.) seedlings were the most widely used rootstocks for a long period in Latvia and Estonia, but they are not suitable for modern plum orchards because they grow too vigorously and are incompati-ble with several cultivars (Lepsis et al, 2004;Rozpara et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

Influence of Rootstocks on Winter-Hardiness of Plum Generative Buds During the Wintering Period in Two Growing Regions

Dēķena

Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences.

Laugale

et al. 2019

The selection of appropriate rootstock is the main precondition for obtaining a high yielding and sustainable plum orchard. In the Northern climate, plum overwintering is especially important, where winter hardiness of flower buds is one of indicators. This investigation was carried out during three wintering periods (2010–2013) at the Institute of Horticulture in Pūre (Latvia) and the Polli Horticultural Research Centre (Estonia), in orchards planted in 2001. The aim of the investigation was to evaluate the influence of different rootstocks on the viability of flower buds during winter for two plum cultivars in two growing regions. European plum ‘Victoria’ and hybrid plum ‘Kubanskaya Kometa’ grafted on eight clonal and eight seedling rootstocks were used in the investigation. Bud samples were taken two times during winter: end of January and end of March. The viability of flower buds and flowering intensity were determined in the laboratory. The viability was determined as dehydrogenase activity using triphenyl tetrazole chloride (0.5%), where in living cells the colourless substance due to enzymatic activity turns into a brightly coloured product — formasan. The optical density of colour was determined with a spectrophotometer at 485 nm. Both cultivars ‘Kubanskaya Kometa’ and ‘Victoria’ had higher flower bud viability in Polli compare to Pūre. In both growing regions, the highest activity of dehydrogenases for cultivar ‘Kubanskaya Kometa’ was on rootstocks ‘Myrobalan’, ‘St. Julien INRA 2’, ‘Wangenheims Zwetsche’ and for cultivar ‘Victoria’ — on rootstocks ‘Ackermann’, ‘Brompton’ seedlings, and ‘St. Julien d’ Orleans’. The dehydrogenase activity of in flower buds had a tendency to decrease during winter.

“…However, this rootstock does not correspond to the demands of commercial horticulture -it produces trees of vigorous growth (Rozpara, Glowacka, 2010;Sitarek, Grzyb et al, 2007). Also, it is not suitable for hobby gardeners if gardens are located in wet soils and if there is incompatibility between rootstock and cultivar observed (Lepsis, Drudze et al 2004).…”

Section: Introductionmentioning

confidence: 99%

Influence of Plum Rootstocks on the Content of Reducing Sugars in the Annual Shoots of Cultivar ‘Kubanskaya Kometa’

Dēķena¹,

Jänes

Proceedings of the Latvia University of Agriculture

2014