interstock, grafted between the rootstock and scion combination, not only can improve tree growth, longevity, fruit production, and quality ( Gil-Izquierdo et al., 2004 ), but also can increase salinity tolerance ( Gimeno et al., 2009b ). The mechanisms
Vicente Gimeno, James P. Syvertsen, Inma Simon, Vicente Martinez, Jose M. Camara-Zapata, Manuel Nieves and Francisco Garcia-Sanchez
The purpose of this invention is to preserve the germplasm which are compatibly graftable for each other in the specific environment. The preserved [interstock] is protected by the rootstock which is used to the stresses from underground, and the “topstock” which is tolerant to the stresses from aboveground.
The compound plant (Top-interstock-rootstock) is different from the traditional combinations which the interstock impove the impatibility between scion and rootstock. The interstock in this design must be compatible with its top and rootstock parts and keep “paradormancy” in the germplasm repository.
Preservation of pear species & cultivars will be presented to describe the details of the techinque.
Stephen M. Southwick and Kitren G. Weis
Selection and propagation of rootstocks for apricot (Prunus armeniaca L.) varies worldwide in response to local climate, soils, and cultivars. In this paper we review published research focused on these local selective practices. Additionally, we review the current development of apricot rootstocks and suggest new research avenues to satisfy the needs of commercial apricot growers. Rootstocks are identified by their responses to biotic and environmental stresses, with specific adaptive characteristics that enable establishment and production under unique zonal ecologies. Desirable characteristics include scion compatibility, adaptation for heavy or wet soils, pest and disease resistance, ease of propagation, control of vegetative vigor, effects on dormant season physiology of the scion, precocity, fruit quality, and productivity. Interstocks that can overcome incompatible rootstock-scion combinations are covered. As worldwide consumer demand for apricots increases with improved apricot cultivars, rootstock selections and propagation must be developed for niche fruit with specific characteristics, intensive production systems, mechanized harvest, and marginal site selection.
William S. Castle and James C. Baldwin
) ( Salibe, 1963 ). A crease forms at the bud union; thus, in P.1, each two-tree plot had one tree propagated directly on Swingle citrumelo rootstock and the second tree was propagated on Swingle citrumelo also but with an interstock of another sweet orange
Jiangbo Dang, Tingrong Wu, Guolu Liang, Di Wu, Qiao He and Qigao Guo
tree with a relatively large size, and dwarf plants are urgently needed to help reduce labor cost in loquat production. The identified aneuploid H39 could be used as a potential germplasm for breeding dwarfing rootstocks or interstocks. Rootstock and
Glenn R. Thayer and Preston K. Andrews
Dwarfing rootstocks are essential for developing high-density pear orchards with increased precocity. The graft compatibility of Amelanchier alnifolia, A. x grandiflora, A. canadensis, and A. alnifolia `Thiessen' as a rootstock for `Anjou' pear or as an interstock on `Bartlett' seedling, `Old Home × Farmingdale' and Crataegus rootstocks are being tested. Twenty rootstock and rootstock/interstock combinations were top grafted 27 Jan. 1994. Ten replicates will be planted in pots for each graft combination in March after callusing. Growth of successful graft combinations will be measured every two weeks. Shoot length and diameter and trunk diameter at a designated reference point will be measured. Leaf color will be evaluated periodically using a Minolta colorimeter. At natural leaffall, leaf areas will be measured. Graft compatibility will be evaluated. All data will be analyzed by analysis of variance.
John A. Barden and Richard P. Marini
Productivity of perennial fruit plants depends to a sizeable degree on partitioning of assimilates between vegetative and reproductive structures. Cultivars and rootstocks modify the partitioning pattern, but there are very few data published on these relationships. The termination of a long-term evaluation of standard-growing and spur-type strains of `Delicious' and `Golden Delicious' on several dwarf and semi-dwarf rootstocks and interstocks provided an excellent opportunity to assess the relationships among cumulative yield, scion weight, and trunk cross-sectional area (TCA). Cultivars were `Goldspur' and `Smoothee' strains of `Golden Delicious' and `Redchief' and `Red Prince' strains of `Delicious'. Rootstocks and interstocks included Malling 9 (M.9), M.26, M.9/Malling Merton 106 (MM.106), M.9/MM.111, M.7, MM.106, and MM.111. Row spacing was standard at 6.1 m. Tree spacing varied with anticipated vigor and ranged from 1.8 to 5.5 m. Pruning times and weight of prunings were recorded in two years. After 18 years, trees were cut off just above the soil line and weighed. TCA and scion weight were highly correlated despite of considerable differences in degree of containment pruning required, and cumulative yields were well correlated with both TCA and scion weight. The ratio of cumulative crop weight to final scion weight decreased quadratically with increasing TCA. Pruning times and weight of prunings were somewhat better correlated with TCA in `Delicious' than in `Golden Delicious'.
ChihCheng T. Chao
The citrus industry in California is changing, and growers are planting more easy-peeling, seedless, and nice-tasting mandarins. Our industry tries to develop new early- and late-season mandarin cultivars to be competitive in the global mandarin market. Seventeen satsuma mandarin (Citrus unshiu Marco.) cultivars were top-worked onto 4–6 Valencia orange [C. sinensis (L.) Osbeck] as interstocks and Carrizo citrange [C. sinensis (L.) Osbeck × Poncirus trifoliata (L.) Raf.] as rootstocks in 30 May 2001 near Santa Paula, Calif. All trees set the first crop in Fall 2003. Fruit maturity of all cultivars was measured based on °Brix level, percent acid, and S:A ratio on a weekly basis since the first week of Sept. 2004. Five cultivars, `Armstrong', `Kuno Wase', `Miyagawa', `S9' and `Xie-Shan' (`Wakiyama'), are very early- or early-season cultivars. A small-scale degreening experiment with 72 h treatment of 0.5 mg·L–1 ethylene with fruit harvested on 6 Oct. 2004 also showed the rind color of all five cultivars could be enhanced nicely. `Miyagawa' had very intense internal orange flesh color visible in the second week of Sept. 2004, comparing with other cultivars. All these five cultivars could potentially become early-season, completely seedless, and easy-peeling satsuma cultivars in California. `Miyagawa' and `Xis-Shan' could potentially be harvested as early as from late September to early October in the central coastal region and from late August to mid-September in the San Joaquin Valley. Both cultivars should command a high price when there is no seedless mandarin in the market.
compatible on `Marianna 2624' plum rootstock; however, growers sometimes prefer this rootstock because of its tolerance to armillaria root rot and heavy, wet soil. To overcome this incompatibility problem, interstocks of `Havens 2B' have been used. Edstrom
Suxiao Hao, Yanfen Lu, Jing Liu, Yufen Bu, Qi Chen, Nan Ma, Zhiqin Zhou and Yuncong Yao
interstock ‘SH6’ as experimental material. We cloned the GID1c gene and compared both its sequence and expression specificity in ‘SH6’ and its parents. By using transient transformation, we also analyzed the transcript level of related genes and hormone