fruit harvest period. Fruit harvest began 22 Mar. 2003 (94 DAP) and peaked ≈19 Apr. (122 DAP) with final harvest occurring the latter part of May. Early girdling significantly decreased fruits per cane and yield per cane compared with the nongirdled
Horacio E. Alvarado-Raya, Rebecca L. Darnell, and Jeffrey G. Williamson
Archana Khadgi and Courtney A. Weber
terminology, the term prickle for the presence of epidermal appendages and prickle-free for the absence is used in this manuscript. The genus Rubus is an excellent member of the family Rosaceae to understand prickle initiation and development. Fruits of the
Jean-Pierre Privé, J.A. Sullivan, and J.T.A. Proctor
Leaf removal, cane girdling, and 14C translocation patterns were used to study source-sink relationships of primocane-fruiting (PF) red raspberries. Although the leaves in the reproductive zone were most important for vegetative and reproductive development, compensatory effects between the cane leaves were evident. When 14C translocation was studied in the reproductive portion of the cane, the lateral closest to the 14C-treated leaf was the major sink for carbohydrate from that leaf, independent of leaf position or reproductive development. Thereafter, partitioning to leaves and/or flowers or fruits above the 14C-treated leaf was related to leaf phyllotaxy 75% of the time.
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.
Hans Spalholz, Mary Jo Kelly, and Marvin Pritts
The use of high tunnels is a technology that can be implemented just about anywhere for a modest cost, and can be used to bring crops on earlier or extend them later in the season. Raspberries are a high value crop that, in season, sell for more than $3.00/lb. In the middle of winter, raspberries can sell for more than $10.00/lb. Our goal was to produce raspberries in October and November, after the field season ends from frost and rain, and when the selling price of raspberries doubles. Our project examined primocane-fruiting varieties and methods of managing plants to delay their production beyond the normal late August-September season. The first part of the study was to monitor the growth and productivity of several late varieties that typically fruit too late for the New York climate. One selection (NY01.64) and one cultivar (Josephine) appeared very promising for high tunnel production. The second set of treatments manipulated `Heritage' so that it fruits later than the normal September season. The five treatments were an unmanipulated control, applying straw over plots in late February at the rate of 6 tons/acre after a period of cold weather, mowing canes to the ground in early June shortly after they emerge, pinching primocanes (removing the top 4–6 inches) when they reach a height of about 2½ ft, and pinching when canes were 3½ ft tall. Each of these 4 treatments delayed flowering and shifted production to later in the season. The late pinching treatment appeared to provide the best yield curve under the high tunnel.
J. Naraguma, J.R. Clark, and R.J. Norman
149 POSTER SESSION 6C (Abstr. 343–353) Nutrition–Fruits/Small Fruits/Nuts
Gina E. Fernandez and Marvin P. Pritts
A 2-year study was conducted to investigate the influence of the light environment on source-sink relationships in `Titan' red raspberry. Treatments imposed included flower and cane removal in conjunction with partial or whole canopy shading. Raspberry plants were remarkably resistant to a reduction in carbon supply. Yields and primocane production were maintained even when canopies were shaded. Furthermore, if raspberry plants were prevented from producing a full crop in one year, yields the following year tended to be higher than normal. These data, and other studies demonstrating that raspberry roots are strong carbon sinks, suggest that raspberry plants may rely on stored carbohydrate to mature the current crop of fruits when current photosynthate is inadequate. This trait is characteristic of some perennial species adapted to progressively changing environments, but may not be optimal for horticultural situations where growing conditions are relatively constant from year to year. A large root storage capacity and excessive primocane production likely contribute to the relatively low yields that are typical of this species.
Andrea Luvisi, Alessandra Panattoni, Roberto Bandinelli, Enrico Rinaldelli, Mario Pagano, Barbara Gini, Giorgio Manzoni, and Enrico Triolo
developed in the European Union ( Sørensen et al., 2010 ). To test RFID tagging procedures in ornamental shrubs, the rose was chosen for the present work. The tagging procedure took into account 1) the possibility of insertion within small diameter canes
Pedro Brás de Oliveira, Maria José Silva, Ricardo B. Ferreira, Cristina M. Oliveira, and António A. Monteiro
. Table 1. Sampling dates for each pruning treatment according to phenologic stage in 1994 and 1995 experiments. Leaf and primocane fresh weight was determined immediately after sampling. For dry weight, cane, leaf and fruits were oven
Fumiomi Takeda, Gerard Krewer, Elvin L. Andrews, Benjamin Mullinix Jr, and Donald L. Peterson
Joonas International, Joensuu, Finland]. Over-the-row mechanical harvesters use horizontal tines or rods to shake the fruiting canes, in either horizontal or vertical directions, to detach the ripe fruit. Detached fruit fall to the catching pans (fish