years for the least precocious. Once in production, yields tend to increase with increasing tree size, up to very high levels of orchard light interception [≈94% ( McFadyen et al., 2004 )]. At even higher levels of light interception, there is some
Lisa McFadyen, David Robertson, Margaret Sedgley, Paul Kristiansen, and Trevor Olesen
W. Todd Watson
Studies have demonstrated that the size of transplanted trees has a measurable impact on establishment rates in the landscape. Larger trees require a longer period of time than smaller trees to produce a root system comparable in spatial distribution to similar sized non-transplanted trees. This lag in redevelopment of root system architecture results in reduced growth that increases with transplant size. Research has demonstrated that smaller transplanted trees become established more quickly and ultimately result in larger trees in the landscape in a few years. Additional studies dispute these findings. This paper provides a review of current research on the effect of tree size on transplant establishment.
Peter C. Andersen and Brent V. Brodbeck
production in the Florida panhandle. The objective of this study was to quantify yield, tree size, and fruit quality of mature (7th to 11th growing season) ‘Brown Select’ and ‘Owari’ satsuma cultivars on trifoliate orange [ P. trifoliata (L.) Raf
Fenton E Larsen and Stewart S. Higgins
The influence of five Old Home × Farmingdale (OHF) rootstocks on tree size with 10 Asian pear scion cultivars was examined after 10 years in an experimental orchard in central Washington state. The effect of rootstock on tree size varied among scion cultivars. Within `Chojuro', `Hosui', `Niitaka', and `Seigyoku', trunk cross-sectional areas were similar regardless of rootstock. Within `Li', OHF 333 produced larger trees than OHF 282 and OHF 217. `Okusankichi' trees, which were generally the same size as `Hosui', were significantly larger on OHF 217 and OHF 97 than on OHF 333. `Kikusui' trees, which were generally similar in size to `Niitaka' and `Seigyoku', were larger on OHF 217, OHF 97, and OHF 282 than on OHF 333. `20th Century', which was similar in size to `Chojuro' and `Shinseiki', appeared to be the cultivar most sensitive to rootstock. `20th Century'/OHF 217 were significantly larger than trees on OHF 97 and OHF 282, which were larger than trees on OHF 51. `Shinseiki'/OHF 97 were larger than trees on OHF 333. The smallest trees were `Shinko', with trees on OHF 217, OHF 97, OHF 333, and OHF 51 all being larger than trees on OHF 282. Contrary to research with some European pear scions, consistent trends did not emerge from this research that would allow a general prediction of the relative influence of these five OHF clonal rootstocks on Asian pear tree size.
Michael W. Smith
and northern Texas orchards. Occurrence of kernel necrosis from additional orchards is reported here. Results of studies of the relationship of kernel necrosis with crop load, tree size, and its distribution in the tree canopy are reported. Materials
Malcolm W. Smith, Jeremy D. Bright, Mark D. Hoult, Richard A. Renfree, Tony Maddern, and Neil Coombes
·ha −1 . Furthermore, the warm conditions necessary to sustain the species often mean vegetative growth is vigorous and significant management inputs are needed to maintain tree size. In tropical regions lacking a distinct “dormancy” period, managing tree
Chih-Cheng T. Chao, Dan E. Parfitt, Louise Ferguson, Craig Kallsen, and Joe Maranto
Trunk cross-sectional area from a population of 6192 pistachio trees was used to estimate tree growth from 1995 to 1997. The narrow-sense heritabilities of trunk cross-sectional area were near zero across multiple locations based on analyses of progenies from 20 half-sib families. However, within individual location, there were values from 0.20 to 0.56 for 1995, 1996, and 1997, respectively. Broad-sense heritability estimates were considerably higher, from 0.36 to 0.64 at multiple locations and 0.51 to 1.35 for individual locations. These results suggest that dominance and significant interaction effects, epistatic and genotype by environment, were important. Breeding strategies should emphasize selection of superior parents based on individual performance, and parents should be selected in the environment in which the progeny are intended to be used.
Neusa M.C. Stenzel, Carmen S.V.J. Neves, José C. Gomes, and Cristiane C. Medina
This study reports the performance (yield, tree size, and fruit quality) of 'Ponkan' mandarin (Citrus reticulata Blanco) on seven rootstocks, evaluated for 11 years under Southern Brazil conditions. Trees on C13 citrange had higher cumulative yield for seven harvests than those on trifoliate orange. Cleopatra mandarin, rough lemon, Rangpur lime, Sunki mandarin, and Volkamer lemon rootstocks maintained their values at an intermediate position and did not present any significant difference regarding C13 citrange, and trifoliate orange. Trees on C13 citrange and on trifoliate orange exhibited the lowest alternate bearing index. Cleopatra mandarin induced the greatest canopy volume, but it was not significantly different from Sunki mandarin and rough lemon. The smallest trees were those on Volkamer lemon and trifoliate orange. The highest yield efficiency came from trees on C13 citrange and the smallest on Cleopatra mandarin. Rootstocks did not significantly affect fruit weight.
Malcolm W. Smith, Mark D. Hoult, and Jeremy D. Bright
Low yields and high harvesting costs are long-standing problems in mango (Mangifera indica L.) cultivation. In an effort to increase productivity in the scion 'Kensington Pride' we examined the impact of nine different rootstocks over a 10-year period. Rootstock effects on fruit production were significant in most seasons, and cumulative yields (nine seasons of cropping) for the best treatment ('Sg. Siput') exceeded those of the poorest treatment ('Sabre') by 141%. Yield efficiencies (expressed on both a trunk cross-sectional area and canopy silhouette area basis) were also significantly affected by rootstock. Rootstock effects on yield and yield efficiency were generally consistent across seasons, despite large seasonal variations in yield. Harvest rates were also influenced by rootstock, and were poorly correlated with tree size. These results demonstrate possibilities for manipulating mango scion productivity through rootstock genotype.
Frank Kappel, Michel Bouthillier, and Rob Brownlee
`Sweetheart' sweet cherry trees (Prunus avium L.) were summer-pruned for four summers (1991-94) either before or after harvest and at two levels, removing 1/3 or 2/3 of current-season growth by heading cuts. In an additional postharvest treatment, some current-season growth was removed by thinning cuts. The preharvest 1/3 treatment had the highest cumulative yield during the experiment. Higher yields were obtained following preharvest than postharvest treatments, and following less severe treatments (removing 1/3 of current-season growth) than more severe (removing 2/3) treatments. These increased yields were for the early stages of orchard production. Average fruit mass was not affected by any of the treatments. The summer-pruned trees had smaller trunk cross-sectional area (TCSA) increments over the trial and their final TCSA was smaller than that of the control trees.