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.
Fumiomi Takeda, Ann K. Hummell, and Donald L. Peterson
Aidan D. Farrell, Sarah Evelyn, Adrian M. Lennon, and Pathmanathan Umaharan
reduced ability to retain water in the floral organ as senescence begins ( Solomos and Gross, 1997 ). As such, genotypic variation in vase life may be driven by water supply or by the senescence response in the bloom. It is currently unclear whether
Marisa M. Wall, Kate A. Nishijima, Lisa M. Keith, and Mike A. Nagao
control diseases, but SO 2 use is prohibited in the United States ( Jiang et al., 2002 ). Longan fruit quality may be retained through modified atmosphere packaging (MAP) in which high humidity, high CO 2 , and low O 2 levels are created inside
Richard P. Marini
Mature `Norman'peach [Prunus persica (L.) Batsch] trees were dormant pruned to retain a range of fruiting shoots per tree (71 to 250) during 3 years from 1997 to 1999. About 40 days after bloom each year, fruits on all trees were thinned to similar crop loads, so only the number of fruits per shoot varied. Fruit set and number of fruits removed by hand thinning were positively related to number of fruiting shoots retained per tree. Number of fruits harvested per tree was not related to number of shoots per tree, whereas average fruit weight at thinning and at harvest, and crop value per tree were negatively related to the number of shoots retained per tree. These results indicate that commercial peach producers should consider modifying pruning and thinning strategies. Rather than retaining a large number of fruiting shoots per tree and hand thinning to distribute fruits every 15 to 20 cm along each fruiting shoot, producers should first determine the number of fruits that trees of a given cultivar can adequately size and then perform the thinning operation to obtain the desired crop load. The number of fruiting shoots retained per tree during pruning should be one-fifth to one-seventh of the number of fruits desired per tree, so that five to seven fruits per fruiting shoot are retained after hand thinning.
`Macoun' is a high-value apple cultivar in the northeastern United States that is very difficult to produce. It is difficult to thin and prone to alternate bearing. `Macoun' is also prone to preharvest drop. Small fruit size, bruising, and lack of red color are additional obstacles to profitable production. The objective of this study was to compare the efficacy of two chemical thinning treatments—accel plus carbaryl, or NAA plus carbaryl—with an untreated control. A second objective was to evaluate the efficacy of ReTain for delaying `Macoun' fruit maturity and to determine if there was an interaction between ReTain and thinning treatment on fruit characteristics at harvest. Both thinning treatments were effective in reducing fruit set in 1997. Accel plus carbaryl was effective again in 1998, while NAA plus carbaryl over-thinned. Accel increased fruit size in 1997 compared to unthinned controls, and both thinning treatments increased fruit size in 1998. Accel increased fruit firmness in both years. ReTain reduced preharvest drop and delayed fruit maturity both years. In 1997, firmness was greatest for fruit treated with accel and ReTain, while ReTain had no effect on firmness of fruit from NAA thinned trees. ReTain had no effect on fruit firmness in 1998.
Keisha Rose-Harvey, Kevin J. McInnes, and James C. Thomas
Golf putting greens and sports fields that are designed to use a geotextile to retain a sand-based root zone mixture atop a drainage layer are an alternative to the popular design recommended by the U.S. Golf Association (USGA) where the root zone
Ming-Wei S. Kao, Jeffrey K. Brecht, Jeffrey G. Williamson, and Donald J. Huber
, although it is known that a ripe NMF fruit may soften to ≈16 N in firmness ( Lurie and Crisosto, 2005 ). The MF peaches in this study became extremely soft during storage (flesh firmness less than 4 N) and the NMF peaches retained greater flesh firmness for
Ellen T. Paparozzi, Jazbaat K. Chahal, Petre Dobrev, Elizabeth A. Claassen, Walter W. Stroup, and Radomira Vankova
stress but are retained, while the latter one responds by abscission of lower leaves ( Borman et al., 2013 ). Preliminary experiments on P. parviflorus demonstrated that this species can be exposed repeatedly to N deficiency conditions and repeatedly
Celina Gómez and James Robbins
by the low cation exchange capacity (CEC) of PBH (less than 1 meq/100 g; Kuczmarski, 1994 ) compared with PB (6.3 to 9.9 meq/100 g; Tucker, 1995 ), which suggests that PBH particles are less likely to retain some nutrients than PB and might be
Charalambos I. Siminis and Manolis N. Stavrakakis
the initial one. Deficient plants not supplied with Fe retained root FCR at low levels ( Fig. 2 ). Root FCR activity in Fe-sufficient plants decreased gradually when Fe was removed from the nutrient solution ( Fig. 3 ). The lowest values were recorded