conducted to examine preferences of blackberry cultivars by Japanese beetles. Two primocane and two floricane cultivars were selected on the basis of the 2017 experiments (the most resistant and the most susceptible in each group): APF-40, Prime
Maciej A. Pszczolkowski, Kyndra Chastain, Rachel Veenstra, and Martin L. Kaps
David Mettler and Harlene Hatterman-Valenti
al. (2003a , 2003b , 2013 ). This trellis system was installed in Oct. 2014, and the blackberry plants were trained according to the protocol used by Takeda. This cane training protocol included the training of up to four primocanes per plant in the
Horacio E. Alvarado, Rebecca L. Darnell, and Jeffrey G. Williamson
Raspberry root growth during fruiting appears to be a strong sink for assimilates, and may decrease carbon availability for fruits and, consequently, cane yield. Both floricanes and primocanes may contribute to root carbon supply in raspberry during fruiting. To test this, `Tulameen' raspberry canes were grown outdoors in containers filled with perlite and peat (1:1). One-half of the plants were girdled and the rest were nongirdled. Within each girdling treatment, either 0 or 3 primocanes were allowed to grow. Treatments were applied at early bloom (10 May), and 50% fruit harvest occurred the first week in June. Fruit number and yield per plant decreased in girdled plants and plants without primocanes compared with nongirdled plants and plants with primocanes. Individual fruit fresh weight was not affected by treatments, but individual fruit dry weight and the dry weight to fresh weight ratio was higher in girdled plants without primocanes than in the other treatments. Neither girdling nor the presence of primocanes affected dry weight allocation to primocanes or floricanes. Root dry weight was higher in girdled plants with primocanes than in nongirdled plants without primocanes. It appears that primocanes supply carbon to roots during fruiting, and subsequently, roots mobilize carbon to floricanes. Thus, roots appear to serve primarily as a translocation pathway for carbon from primocanes to floricanes. However, when primocane growth is suppressed, root carbon is mobilized to support floricane development. If carbon flow from roots to floricanes is restricted, fruit number and yield is significantly decreased.
J. J. Luby, E. E. Hoover, D. S. Bedford, S. T. Munson, W. H. Gray, D. K. Wildung, and C. Stushnoff
‘Redwing’ is a primocane-fruiting (“fall-fruiting”) red raspberry (Rubus idaeus L.) cultivar (Fig. 1) developed by the Univ. of Minnesota fruit breeding program. It typically begins fruiting 10 to 14 days earlier than ‘Heritage’, the most widely grown commercial primocane-fruiting cultivar. ‘Redwing’ is intended to supplement or replace ‘Heritage’ in situations where earlier primocane fruiting is desired.
Fumiomi Takeda, Ann K. Hummell, and Donald L. Peterson
Mature 'Chester Thornless' blackberry plants were trained to the rotatable cross-arm (RCA) trellis to determine the effect of retaining two, four, or six primocanes on plant productivity. Retention of only the two oldest primocanes and generally the most vigorous primocanes per plant yielded 14.1 kg of fruit compared to 17.1 kg per plant in which as many as six primocanes were retained. Increasing the number of canes did not result in significant yield increase (P = 0.09) because the primocanes trained in late-June and July produced only a few, and, in some cases, no lateral branches. Thus, retaining only those canes that become trainable early in the season decreased labor inputs and allowed primocane training to be completed prior to the onset of harvest. As a result, the effort to train and retain only those primocanes that reach the trainable height before mid-June may be advantageous to minimize labor costs, but will not effect plant productivity.
Saki Toshima, Marika Fujii, Momoko Hidaka, Soya Nakagawa, Tomonari Hirano, and Hisato Kunitak
mutation-breeding processes. Also, raspberry cultivars can be divided into two types according to the characteristics of fruit sets, floricane (FC)-fruiting, and primocane (PC)-fruiting ( Heide and Sønsteby, 2011 ). PC-fruiting cultivars go through the
Javier Fernandez-Salvador, Bernadine C. Strik, and David R. Bryla
, 1986 ). Recommended rates of N application in conventional plantings vary with age and cultivar of blackberry grown, ranging from 25 to 70 lb/acre N ( Bushway et al., 2008 ; Hart et al., 2006 ). In blackberry, primocane leaf nutrient concentration
Graeme R. McGregor
Application of daminozide to young ‘Heritage’ primocanes significantly increased early yields by increasing the number of fruit that ripened on lower fruiting laterals. Daminozide at 2000 ppm applied to 30-cm-high primocanes would enable a commercial crop to be harvested in districts otherwise unsuitable for autumn production. Chemical names used: butanedioic acid mono(2,2-dimethylhydrazide (daminozide).
of the above acreage is under multi-bay tunnels and the vast majority of the raspberries produced are from primocane-bearing cultivars. In states mostly in the upper-midwestern and northeastern United States, single-bay tunnels are more commonly used
Jessica M. Cortell and Bernadine C. Strik
In Spring 1993 and 1994, mature trailing `Marion' blackberry (Rubus L. subgenus Rubus Watson) plants were pruned to 0, 4, 8, and 12 floricanes. In 1994, yield per cane was higher for plants with 4 floricanes compared to plants with 8 or 12 floricanes. In Summer 1993, there was a trend for lower primocane dry mass with a higher floricane number and a significant reduction in primocane branch dry mass with an increase in floricane number. Total plant, fruit, floricane, and lateral dry mass increased linearly with floricane number. Results were similar for floricane components in Summer 1994; however, there were no treatment effects on primocane or branch dry mass and there was a significant linear increase in crown dry mass with floricane number. By Winter 1994-95, there were no treatment effects on primocane or crown dry mass. Plants without floricanes produced more primocanes per plant than plants with floricanes in 1993 but not in 1994. Plants without floricanes produced primocanes that had a significantly lower percent budbreak the following year (1994) than plants with floricanes. Primocanes produced by plants without floricanes had more nodes per branch and a greater average branch cane length than those from plants with floricanes the previous season. The number of nodes per primocane tended to decrease with an increase in floricane number per plant in 1994 and 1995. There was no significant effect of floricane number per plant the previous season on fruit per lateral, fruit mass, or yield per plant the following season in either treatment year (1993 + 1994). However, in 1994, plants without floricanes the previous year had the lowest yield per cane. Topping primocanes at 30 cm in 1993 and 1994 had few significant effects on yield components the following season. Thus, `Marion' blackberry can compensate for reduced fruiting cane number through an increased percent budbreak on remaining canes. While there were differences in primocane dry mass among treatments after harvest in 1993, there were no differences by mid-winter in either 1993 or 1994. Although plants grown without floricanes in 1993 had more primocanes, these canes had a lower percent budbreak the following season. Consequently, in this study we did not see increased yield in plants grown without floricanes the previous season. This was perhaps because primocanes were not trained as they grew, a practice that improves light exposure to the canes and may increase flower bud initiation.