The relationship of variability in flowering and fruiting habit to canopy position and changing diurnal light and photosynthetic pattern was examined in 7 mature spur-type `Red Delicious'/MM106 apple trees. A .5×.5m column was placed in the north, south, east and west sections of tree canopies. Columns were subdivided by height with 3 study areas located at .25-.5m, 1.0-1.25m and 1.75-2.0m from the top of the canopy. In each, section, flowering index, fruit set, individual fruit weight and size, skin coloration, fruit soluble solids content, spur leaf area and spur bud diameter were determined. Photosynthetically active radiation and photosynthesis were measured from bloom through harvest correlated with variability in flowering, fruiting, spur quality and distribution of growth.
Renae E. Moran and Curt R. Rom
Ian J. Warrington, David C. Ferree, James R. Schupp, Frank G. Dennis Jr., and Tara A. Baugher
The characteristics of 1-year-old vegetative spurs growing on 2-year-old branches were measured on 28 `Delicious' apple (Malus domestica Borkh.) strains growing on M.7 rootstocks at Clarksville, Mich., and on 23 strains of `Delicious' on M.7a rootstocks at Kearneysville, W.Va. Spur-type strains typically had densities >20 to 21 spurs/m, and high spur leaf numbers, leaf areas per spur, leaf areas per leaf, and terminal bud diameters, whereas values for standard strains were generally lower. However, for most spur quality characteristics, there was a continuous range of values between the extremes rather than any distinct grouping into either spur or standard type. At both sites, spur density was significantly and positively correlated with yield efficiency. In a related study, the spur characteristics of `Starkspur Supreme' were measured on nine rootstocks: M.7 EMLA, M.9 EMLA, M.26 EMLA, M.27 EMLA, M.9, MAC 9, MAC 24, OAR 1, and Ottawa 3. Spur leaf number and spur leaf area were both high with vigorous rootstocks, whereas spur density was low. The rootstocks MAC 9, M.9, and M.9 EMLA had the highest yield efficiencies.
Gabino H. Reginato, Víctor García de Cortázar, and Terence L. Robinson
. Konishi, B. Dilley, M. 1991 Light level influences spur quality and canopy development and light interception influence fruit production in apple HortScience 26 993 999 Blanco, A. Pequereul, A. Val
Mokhles A. Elsysy and Peter M. Hirst
bearing potential on spur quality and leaf gas exchange in apple J. Amer. Soc. Hort. Sci. 144 31 37 Esumi, T. Tao, R. Yonemori, K. 2005 Isolation of LEAFY and TERMINAL FLOWER1 homologues from six fruit tree species in the subfamily Maloideae of the
Haishan An, Feixiong Luo, Ting Wu, Yi Wang, Xuefeng Xu, Xinzhong Zhang, and Zhenhai Han
agroforestry system Plant Soil 401 409 426 Head, G.C. 1969 The effects of fruiting and defoliation on seasonal trends in new root production on apple trees J. Hort. Sci. 44 175 181 Hirst, P.M. Ferree, D.C. 1995 Rootstock effects on shoot morphology and spur