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to compensate for the declining native variability by deliberate maintenance. This study is an attempt to describe a functional breeding andMajor breeding objectives in snap bean (Phaseolus maintaining program of intraselection in a traditional snap bean vulgaris L.) concern the development of cultivars com-(Phaseolus vulgaris L.) cultivar. The program was applied in three bining high productivity, stable yields, earliness, pest stages. The first thing examined was the existing genetic variability of source material for earliness and pod yield potential. Single-plant and disease resistance, tolerance to environmental frequency distributions with positive skewness for earliness showed stresses, and desirable agronomic-horticultural attrithat the frequency of unfavorable alleles was high. For total pod butes (Silbernagel, 1986; Singh, 1992). The achievement yield, distribution was found normal. Thus, the end-target should be of such objectives should take into account the cropping selection for early maturity, keeping, and stabilizing high yield. The systems, the ecological conditions, and the preference seed shape uniformity was added as third criterion of selection. Secof consumers in the target areas. In temperate areas ondly, combined pedigree intraselection, based on widely spaced sinof monocropping and intensive cultivation, mechanical gle-plant performance, for the prementioned traits was applied for cultivation, and industrial processing of the final product three successive generations. The evaluation of the third-generation have directed efforts to breed varieties with determinate families revealed progenies with high yield, earliness, and stability of bush type, short duration, concentrated pod maturation, performance. Thirdly, the end-product of the program applied was and uniformity in plant height, seed shape, and size. to restore or even improve the cultivar. The evaluation of improved selections of fourth-generation families and of the source material, Much of the genetic improvement of snap bean has at dense stand, showed that all families were the only ones producing been achieved through the selection of varieties by high and stable early fresh pod harvest, even 53 d after planting applying conventional breeding techniques of self-polli-(53.25-80 g/plant, compared with 0 g/plant of the control). The total nated crops (Singh, 1992) such as bulk, pedigree, backpod yield of all the families was 219 to 276% superior compared cross, and their modifications (Brim, 1966) such as the with source material. Conclusively, the widely spaced single-plant single seed descent method. Conventional pedigree secombined pedigree intraselection was proved reliable and effective lection based on visual evaluations may be difficult, in restoring or even improving the local cultivar of snap bean according especially for traits with low to moderate heritability to update demands.such as seed yield (Patino and Singh, 1989). Bulk breeding methods were effective for endowing genotypes with a better yield stability (Allard,...

The aim of this work was to assess growth traits during the initial developmental stages of olive seedlings, which could be correlated to time to first flowering, facilitating fast selection in olive breeding programs. The experimental material consisted of 232 olive seedlings derived from controlled crosses of 'Kalamon' with self (KA × KA), with 'Amphissis' (KA × AM), and with 'Koroneiki' (KA × KO) and from open pollination of 'Kalamon', 'Amphissis', 'Koroneiki', 'Chalkidikis', and 'Manzanillo'. Vegetative traits of the seedlings, including canopy height and diameter, length of lateral vegetation, number of leaves, mean and total leaf area per plant, leaf shape characteristics, and specific leaf area (SLA), were recorded until 15 months after sowing. The first seedlings to initiate flowers, 4 years after sowing, were also recorded. The existence of correlations between the above growth traits and time to first flowering was investigated. In single-branched seedlings 6 months after sowing, height measured at this stage was significantly correlated with the mean and total leaf area per plant, specific leaf area, and other vegetative traits measured 15 months after sowing. Seedlings with high values of these parameters were the first to initiate flowers 33 months later. Our results indicated that pre-selection of olive seedlings for earliness of first flowering is possible, based on vegetative characteristics assessed very early in their development.

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The concentrations of free and non-free spermidine and spermine in vegetative (leaves, shoot apices) and reproductive (lateral buds, ovaries, fruit tissues) olive organs were determined. The aim was to investigate whether the seasonal fluctuations of these polyamines in different organs correlated to developmental processes such as floral differentiation, shoot growth, anthesis, fertilisation, and fruit growth. Samples were taken from trees of the large-fruited cultivar Chondrolia Chalkidikis and the small-fruited Koroneiki. High levels of both polyamines were determined in buds and shoot apices during the cold period, especially in Ch. Chalkidikis, possibly connected to cold-hardiness exhibited by this cultivar. Two peaks of total spermine in buds, the first occurring in January–February and the second in mid April, coincided with the morphological differentiation of flowers and the inflorescence emergence, respectively. Polyamine levels in ovaries dropped after ovule fertilisation and remained low during the subsequent growth of fruit tissues. Spermidine accumulation, especially in the non-free form, was recorded around the middle of August during a period of intense physiological activity in olive connected to embryo and fruit growth, endocarp hardening, and preceding the second flush of growth in early September. The data showed a direct relationship, in terms of time, of polyamine fluctuations with developmental processes in olive. Whether polyamines act, in this respect, as nitrogen providers or assume a more active regulatory role remains to be elucidated.