Hort. Sci. (Prague)Vol. 37, 2010, No. 4: 121-126 The rootstock is one of the most important factors influencing the profitability of fruit growing. It offers flexible and often the cheapest method of tree vigour control (Webster 1993). A mistake made in selecting the rootstock may adversely affect productivity throughout the lifetime of the orchard. Most modern commercial orchards are planted on dwarfing and semi-dwarfing rootstocks. In many countries, M.9 has become the dominant rootstock for apple because of its suitability for high-density plantings (Wertheim 1997). Nevertheless this rootstock has certain shortcomings such as poor propagation in stoolbed, bad anchorage in soil, brittle roots and susceptibility to fire blight, crown gall, and winter cold injury. These negative characteristics of M.9 became the challenge for the breeders and nurserymen to find clones having better quality traits than the standard M.9. Difficulties in propagating the original Malling selections of M.9, including the virus-free EMLA clone, prompted nurserymen in several European countries to reselect within the existing M.9 populations for subclones exhibiting improved propagation on the stoolbed. There are now many M.9 subclones originating in the Netherlands (NAKB 337-340 and Fleuron 56), Belgium (Nicolai 29), Germany (Burgmer), and France (Pajam 1 and 2) as well as the wellknown EMLA subclone (Webster et al. 2000). At present more than 25 sub-clones of M.9 are bred in Europe. These clones have been tested in different climatic and soil conditions. The results of their evaluation are not clear and tests should continue (Warmund 2001;Ladner et al. 2003;Stehr 2005;Dierend, Bier-Kamotzke 2009). This study was

ABSTRACT:A plum rootstock trial with Stanley and Cacanska najbolja cvs. was established in spring 1992. The following rootstocks were assessed: MY-BO-1, Myrobalan SE 4043 (both Prunus cerasifera), MY-KL-A (P. cerasifera × P. cerasifera var. atropurpurea), Marunke SE 4034 (Ackerman), St. Julien A, Brompton, GF 655/2, GF 1869, GF 1380, GF 43, Damascena SE 4045, Pixy and Myrobalan seedling. Yields, trunk cross-section area, number of suckers and mean fruit weights were evaluated in the orchard in 1993-2003. There were statistically significant differences in trunk cross-section area, yield and yield efficiency between the tested rootstocks. Trees of Stanley were the most vigorous on MY-KL-A, followed by GF 43, GF 1380 and Myrobalan seedling. The weakest growth was recorded on trees grafted on Pixy, then on GF 655/2 and MY-BO-1. With Cacanska najbolja the growth was the strongest on GF 43, followed by Myrobalan seedling, MY-KL-A and Myrobalan SE 4043. The most compact trees were on Pixy and then on GF 655/2 and Marunke SE 4034. The total accumulated yield per tree was the highest with Stanley on MY-KL-A, followed by Brompton and St. Julien A. The cultivar Cacanska najbolja was most productive on Myrobalan SE 4043 and also on St. Julien A. The yield efficiency with both cultivars was the highest on GF 655/2, and the lowest one on GF 1380 (Stanley) or on Myrobalan seedling (Cacanska najbolja). No statistically significant differences between the tested rootstocks were found in fruit size. Suckers were the most prolific on GF 1869, followed by GF 655/2 and Marunke SE 4034. Based on the hitherto experience, the best rootstocks for Stanley seem to be MY-KL-A and MY-BO-1 and for Cacanska najbolja Myrobalan SE 4043 and St. Julien A.

Mészáros M., Kosina J., LaňarL., Náměstek J. (2015): Long-term evaluation of growth and yield of Stanley and Cacanska lepotica plum cultivars on selected rootstocks. Hort. Sci. (Prague), 42: 22-28.During 1992-2012, trunk cross-section area (TCSA), cumulative yield, yield efficiency and suckering of plum cultivars Stanley and Cacanska lepotica in combinations with vegetative rootstocks Myrobalan SE 4043, Myrobalan SE 4044, MY-KL-A, GF 655/2, GF 43, Damas C SE 4045, Pixy, St. Julien A and generative rootstock Myrobalan seedling were evaluated. The results indicated significant differencies of the characteristics between the evaluated cultivar/rootstock combinations for each cultivar. The long-term experience indicates that the evaluated characteristics of the trees on different rootstocks can significantly change during the ontogenetical developement in the orchard. This is demonstrated by the difference in the entering into the bearing stage, different abudance of the yields, the time of reaching of maximum yields and also in changes of growth intensity. For detailed description of the rootstock characteristics long-term trials are required. For cv. Stanley, Myrobalan SE 4043 is the best rootstock for long-term orchards and St. Julien A for orchards with a higher replanting rate. For cv. Cacanska lepotica, Myrobalan SE 4043 seems to be the best rootstock.Keywords: ontogenesis; stage; productivity; TCSA; bearing; suckering Plum is one of the traditional fruit crops grown in the Czech Republic. For good performance in the orchards, the rootstock has an important influence on the scion cultivar. The most frequently used rootstock in Czech Republic is still the myrobalan seedling. With the increased need for intensification of fruit production, several rootstock trials have already been established and evaluated in central Europe (Hrotkó et al. 1998;Kosina 1998Kosina , 2007Sosna 2002;Sitarek et al. 2007) in order to find more productive scion-rootstock combinations. Authors in these publications presented results of the influence of new rootstocks, described by Hrotkó et al. (1998), Jakob (1992, Hartmann (1995), andWebster (1997), on selected plum cultivars, nevertheless most of them are results from young orchards, which just enter the productive stage. It is interesting to supplement this information with long-term results.Experience from international rootstock trials shows that the performance of a rootstock in combination with the cultivar may change in different agroclimatic conditions (Hartmann et al. 2007). That is the main reason to test the same rootstocks in different regions of Europe and of the world. However, the question is, if the rootstock with the cultivar retains qualities in growth and bearing throughout the ontogeny

This study was conducted in the Research and Breeding Institute of Pomology in Holovousy in order to test some new pear rootstocks under the conditions of the Czech Republic. In a rootstock trial planted in spring 1996 five clonal rootstocks (OH &times; F 69, OH &times; F 87, OH &times; F 230, OH &times; F 333 and standard Quince BA-29) were compared with Red Barttlet, Conference and Lucas as test cultivars. In comparison with Red Barttlet, the cumulative yield per tree from 1996 to 2002 was the highest on <br />OH &times; F 69 and the lowest on OH &times; F 333. The yield efficiency (kg/cm²) was best on BA-29. The cultivar Conference had the highest total yield and yield efficiency on OH &times; F 87. The lowest yield was on OH &times; F 333. The cultivar Lucas was the most productive on OH &times; F 87. In the sixth year after planting no difference was observed in growth vigour (indicated by trunk crosssectional area) between OH &times; F clones with the cultivar Red Barttlet. The trees on BA-29 grew less. The tree size of Conference was largest for OH &times; F 230 and smallest for OH &times; F 333. The cultivar Lucas grew vigorously on OH &times; F 69. Small trees were observed on the rootstock OH &times; F 87. Fruit weight was higher on BA-29 than on OH &times; F rootstocks with all cultivars. The production of <br />suckers proved to be small with all cultivars on all rootstocks. The anchorage of all trees was adequate. No graft incompatibility has been detected yet. The results were processed statistically. &nbsp;

No abstract