Adaptation of microclones of blackberries to in vivo conditions

The results of studying the effect of mineral fertilizing on rhizogenesis and the development of aboveground organs of regenerant plants of blackberry thornless adaptable to in vivo conditions in the laboratory of selection, vegetable growing and horticulture, cloning “UNITS” Agrotechnopark “of Belgorod State Agrarian University are presented. Regenerated plants of thornless blackberry cultivar Agavam were adapted to in vivo conditions in a peat-perlite mixture with the addition of microelements and growth regulator root 16 days earlier than in the control. An active growth of the aboveground part and roots of regenerated plants of thornless blackberry was noted on the 21st day, in the control - on the 42nd day after the start of adaptation. By the end of the rooting stage on the 24th day, the regenerant plants formed an aerial part of two pairs of leaves 22 mm high and a developed root system - 37 mm. The mineral and hormonal composition of nutrient media for the cultivation of thornless blackberries has been optimized, an effective combination of physical and chemical factors at different stages of micropropagation has been determined, which enhance the proliferation of shoots and roots, and the dependence of the efficiency of adaptation of regenerated plants to in vivo conditions has been established. Along with traditional breeding methods, new opportunities for solving the problem of thorn-free blackberry varieties are provided, along with traditional breeding methods, which make it possible to accelerate the process of obtaining valuable planting material to provide the population and the processing industry with valuable berry products.

Blueberry and Blackberry are Tolerant to Repeated Indaziflam Applications

Numerous perennial horticultural crops are grown across the southeastern US. Blueberry and blackberry (also known as caneberry) are commonly found in roadside stands, promote agritourism with the pick your own markets, are important for fresh market commercial production in the region, and when processed, provide desirable value added products. Season-long weed control using residual herbicides is crucial for these perennial fruit crops to maximize berry quality and yield. Studies performed from 2012 to 2014 in Lanier and Clinch counties in Georgia evaluated the effects of repeated applications of indaziflam at 35, 75, or 145 g ai ha-1 applied biannually in March and September (5 total applications) on growth of ‘Alapaha’ rabbiteye and ‘Palmetto’ highbush blueberry, and ‘Apache’ thornless blackberry. All indaziflam treatments were mixed with glufosinate, and a glufosinate only treatment was included as a check. Minor leaf chlorosis (<10%) was noted within 30 days after application for all blueberries for all treatments, but this was always transient. Blueberry stem diameter was not different for any treatment, even when indaziflam was applied up to 725 g ai ha-1 over three years as compared to glufosinate alone. There was no chlorosis or stem diameter differences for blackberry noted for any treatment. Indaziflam applied in blueberry and blackberry production provides season-long control of numerous troublesome weed species, without causing injury or negatively impacting crop growth.

Intercropping Winter Greens between Blackberry Rows for Year-round High Tunnel Production

A decrease in available farmland worldwide has prompted interest in polyculture systems such as intercropping where two or more crops are grown simultaneously on the same land to increase the yield per farm area. In Alcalde, NM, a year-round intercropping system was designed to evaluate organically produced blackberry cultivars (Rubus, subgenus Rubus) and winter greens in a high tunnel over a 2-year period. Two floricane fruiting blackberry cultivars, Chester Thornless and Triple Crown, were grown intercropped with ‘Red Russian’ kale (Brassica napus) and ‘Bloomsdale’ spinach (Spinacia oleracea) in a high tunnel. In an adjacent field, the planting of blackberry was repeated with no winter intercrop and no high tunnel. Both cultivars of blackberry were harvested July to September, and fresh weights were measured to determine suitability to the intercropping system in the high tunnel. Both species of winter greens were harvested January to April, and fresh yield weights were measured to discern fitness as possible intercrops in this system. Row covers were used for kale and spinach, and air temperatures were monitored November to April inside the high tunnel. High tunnel temperatures were within acceptable ranges for the production of greens with the use of rowcovers. Yield data from this study indicates that ‘Triple Crown’ blackberry outperformed ‘Chester Thornless’ blackberry in both the high tunnel and field trials with significant difference in the second season. Additionally, blackberry yields from both cultivars were observed to be higher in the field than in the high tunnel for both years. High temperature damage to high tunnel berry canes was noticed for both cultivars, with observed yield decreases in the second year in the high tunnel. Overall, this study indicates that the phenology and climate needs of the two winter greens and blackberry cultivars were not compatible for sustaining year-round organic high tunnel production.

Micropropagation of ‘Chester thornless’ Blackberry Cultivar using Axillary Bud Explants

Sexual propagation is not suitable for production of true to type plants for commercial cultivation of selected cultivars due to the having heterozygous characteristics. Rubus species are highly heterozygous and therefore when they are propagated by seeds the high plant variability is obtained. Micropropagation methods became very important and have many advantages compared to the classical propagation methods. In Turkey, blackberries are commonly propagated by hard and soft wood cuttings, by layering and bush division. Propagation by layers requires rather large area for a layered, and weed control among the layers is a problem. However, propagation by cuttings is connected with important problem in inadequate rooting, especially in ‘Chester Thornless’ cultivar, which is one of the most commercially grown cultivar. In addition, limited number of plants can be propagated using classical propagation method and thus demand of growers for the plants can not be satisfied. Optimized and highly efficient regeneration protocols are also important for genetic transformation for improving of new cultivars. In this study we focused on optimization of protocol for in vitro propagation of ‘Chester Thornless’ blackberry cultivar using nodal segments. For this purpose, explants were cultured on Woody Plant Medium (WPM) supplemented with combination of plant growth regulators BAP (1.5, 2, 3 mg/l) with NAA (0, 0.1, 0.2, 0.4 mg/l) to detect the best multiplication medium. According to the obtained results, the highest proliferation rate was obtained for cultivar ‘Chester Thornless’ that produced 9.66 shoots on a medium containing 2 mg/I BAP+0.2 mg/I IBA combination. GA3 effects on multiplication rates were also studied and generally the highest rates obtained by while GA3 were not used. For the rooting, different concentrations of IBA and NAA (0, 0.1, 0.2 and 0.4 mg/I) were compared. A concentration of 0.4 mg/l NAA gave the greatest number of roots and maximum root length.

Chemical composition, biological potentials and antimicrobial activity of wild and cultivated blackberries

The aim of this study was to compare the chemical compositions and biological potentials (antioxidant potentials, ?-glucosidase test and antimicrobial activity) of wild and cultivated blackberry varieties from two different locations. The chemical compositions were evaluated in fresh samples, while the biological potentials were measured in dry blackberry extracts. The highest dry matter (15.73 g/100 g fw) was obtained for wild blackberry from Verici (Bw2). The significantly higher content of sugars (6.07 g/100 g fw) and ascorbic acid (21.36 g/100 g dw) was found in Chester Thornless blackberry (Bc1) comparing to other samples. The wild blackberry from Javorani (Bw1) showed the highest amount of polyphenols, as well as antioxidant potentials on DPPH (184.26 mmol Trolox/kg dw), ABTS (340.26 mmol Trolox/kg dw) and OH (944.03 mmol BHT/kg dw) radicals. The antihyperglycemic potentials of the extracts were determined by the ?-glucosidase test. The cultivated blackberry Cacanka Bestrna (Bc2) showed the stronger inhibition of ?-glucosidase enzyme (?-GIP = 50.69 %) than other varieties (p<0.05). Wild blackberry extracts showed higher antibacterial and antifungal activity towards Staphylococcus aureus, Escherichia coli, and Aspergillus niger. The results presented in this study indicated the differences between wild and cultivated blackberry varieties, as well as mutual differences in chemical composition, polyphenol contents, biological potentials, along with the antimicrobial activity of wild and cultivated blackberry varieties from two different locations in Bosnia and Herzegovina.