Relationship of Seasonal Changes in Carbohydrates and Cold Hardiness in Canes and Buds of Three Red Raspberry Cultivars

Abstract

<jats:p>Canes of three field-grown cultivars of red raspberry (<jats:italic>Rubus idaeus</jats:italic> L. `Maurin Makea', `Ottawa', and `Muskoka') were sampled from October to April. Carbohydrate contents of canes and flower buds were analyzed, and cold hardiness (LT<jats:sub>50</jats:sub>) was determined by controlled freezing. Starch, sucrose, glucose, fructose, and minor amounts of raffinose and stachyose were present in both cane and bud tissues. Glucose and fructose were the predominant sugars in buds. In canes, the proportion of sucrose of all sugars was greater than in buds. Seasonal changes in carbohydrates were related to changes in cold hardiness and mean air temperature during a 5-day period preceding sampling. Starch decreased during fall and was barely detectable in midwinter. Soluble carbohydrates accumulated to 73 to 89 mg·g<jats:sup>-1</jats:sup> dry weight in canes and 113 to 131 mg·g<jats:sup>-1</jats:sup> dry weight in buds in midwinter. The most striking increase occurred in the concentration of sucrose, but glucose, fructose, raffinose, and stachyose also accumulated. There was a positive correlation between LT<jats:sub>50</jats:sub> and the amount of starch, but a negative correlation between LT<jats:sub>50</jats:sub> and the amounts of total soluble carbohydrates, sucrose, glucose, and fructose. High levels of sucrose, total soluble carbohydrates, and a high ratio of sucrose to glucose plus fructose were characteristic of a hardy cultivar. Results are evidence of the importance of carbohydrate reserves, especially sucrose, on winter survival of red raspberry.</jats:p>

Flower Bud Cold Hardiness of ‘Muskoka’ Red Raspberry as Related to Water Content in Late Winter

“…This relationship was closer in the shoots than in the buds, as has been observed in our earlier studies (Palonen, 1999). Cold hardiness in raspberry shoots seemed to react more readily to the changes in air temperature.…”

Cropping potential of raspberry long-cane plants is affected by their growing conditions and duration of cold storage

“…During the same time period, starch concentrations decreased by 45 mg g -1 DW and 183 mg g -1 DW in canes and roots, respectively. This conflicts with our earlier study in which the amount of hydrolysed starch was correlated with an increased concentration of soluble carbohydrates in over-wintering raspberry canes under northern conditions (Palonen, 1999). We assumed that the carbohydrates were consumed for respiration during storage.…”

“…We are not aware of any other reports on carbohydrate reserves in raspberry long-cane plants during cold storage, although carbohydrate concentrations in overwintering plants in the field (Crandall et al, 1980;Palonen, 1999) and during fruiting (Crandall et al, 1974;Whitney, 1982) have been studied. Raspberry plants store large amounts of carbohydrates in their root system (Fernandez and Pritts, 1996), as shown in our study by the high starch concentrations.…”

“…Carbohydrate concentrations in the cane have been determined during the growing season (Crandall et al, 1974;Whitney, 1982) and in over-wintering raspberry plants in the field (Crandall et al, 1980;Palonen, 1999), but not, to our knowledge, during the cold storage of plants. Lieten et al (1995) showed that total carbohydrate reserves diminished by 32 -56% during cold storage of strawberry (Fragaria ϫ ananassa), which contributed to the lower cropping potential of plants after an extended period of storage.…”

The influence of the cooling of donor cultures on the in vitro adventitious regeneration and carbohydrate metabolism of four dwarfing apple rootstocks

“…After transfer to control conditions, stachyose completely disappeared, confirming the transient accumulation of stachyose in response to stress. In the shoot apices of Lonicera caerulea and canes or buds of raspberry, the accumulation of raffinose and stachyose was detected during cold acclimation (Imanishi et al 1998;Palonen 1999), but to a lower level than that in apple cultures. Although there was a high positive correlation (r 2 = 0.86) between the concentration of RFOs and the ability of apple rootstock cultures to regenerate, there is no available data on the possible role of RFOs in regeneration.…”