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Genetic diversity of the inbreed lines used in hybrid formula is a major component of the final success of sweet corn commercial hybrids. The purposes of the presented paper were to identify and prognosticate the performance of Sugary 1 sweet corn inbreed lines, on the basses of their variability expressed at the phenotypic and genotypic levels. In this respect 18 inbreed su lines, developed at Turda (Romania) Agricultural Research and Development Station (ARDS) were studied concerning the phenotypic and genotypic diversity of ear weight, ear length, no. of rows/ear and depth of kernels. The results obtained have shown that T152su, T339su, TA28su, TD10su, TA26su, TC209su lines have registered high values for the phenotypic expression if the studied characters. T339su, TA28su transmit positive additive genetic effects for the studied characters. The most obvious differences at the non additive genetic level were found in T339Rsu with T244su, T193Asu with T233su, TC209su, TA27su with T244su si TC209su and T152su with TC209su.

Phenotypic selection in apple seedling populations (F1), derived from semidiallel hybridizations between genitors with different peculiarities (Florina and Liberty, resistant to apple scab attack; Starkrimson and Golden spur, with spur ideotype) was completed with Marker Assisted Selection (MAS), based on Bulk Segregant Analysis (BSA) technique. Molecular analyses performing by Bulk Segregant Analysis were intended to indentifying markers for scab resistance, powdery mildew resistance and architectural tree structure (ideotype) with bulks of five to six plants per groups, and testing the bulks with RAPD polymorphic primers. The polymorphic bands between the bulks were mostly associated to apple scab resistance genes. Concerning powdery mildew resistance and architectural tree structure analysis the results are inconclusive. Although it seems that the primer 54 showed a polymorphic band in a resistant to powdery mildew hybrid, which is missing in the sensitive hybrids, the result is only apparently favourable since this band is present in both parental forms (Starkrimson, tolerant to powdery mildew and Liberty, relative susceptible). Molecular profile of the standard ideotype and spur ideotype, resulted in hybrids originated in standard parental form (Florina) and spur parental form (Golden spur), were usually monomorphic. Genetic association among the parental molecular polymorphism for scab resistance and the other two important traits (powdery mildew resistance and ideotype), was not conclusive.

Five apple cultivars (‘Florina’, ‘Golden Delicious’, ‘Idared’, ‘Jonathan’ and Starkrimson), were tested in 2004 and 2005 in five commercial orchards located in different counties of Transylvania, Romania, with quite nonsimilar environments. In June, young shoots were harvested from each cultivar and taken to the laboratory by means of a refrigerating bag. Young leaves were harvested from the shoots and preserved in refrigerator at –70oC until the DNA extraction was performed. Twelve decamer primers were used for DNA amplification out of which ten produced polymorphic bands in each cultivar/location. A dendrograms was constructed based on DNA migration in agarose gel and analysis of formed bands and genetic distances, for revealing the intervarietal polymorphism in the five locations. As it has been expected, at the molecular level there were great differences among the tested cultivars, but the dendrogram also exhibited the existence of obvious differences, at the molecular level, within the same cultivar, depending on location. Such differences should be attributed mainly to the lack of uniformity of initial mother plants used in the process of planting material production for the five cultivars under study. It is concluded that RAPD analysis could successfully be used in checking the authenticity of planting material for apple trees produced in different nurseries, provided there are available standard forms of the interested cultivars from which DNA could be analyzed and used as control.

The number of branches per tree was analysed on F1 individuals originated in several crosses between apple cultivars with different architectural ideotypes: spur (Starkrimson, Golden spur), semispur (Liberty), weeping (Florina). The number of branches per tree in F1 hybrid apple, in their third year of vegetation, was different in six combinations, depending on the genotype of genitors, respectively on their architectural ideotype. There have been noticed significant differences among the tested cultivars used as genitors, the average of trait on hybrid combination being comprised between 4.28 in Goldenspur x Liberty and 7.14 in Starkrimson x Florina. A small number of branches per seedling were registered in Starkrimson x Goldenspur combination (4.32), where the both genitors are spur ideotypes. The variability of analysed characters was high, with s% between 33.9 at Liberty x Florina and 56.8 at Starkrimson x Liberty. These values suggest that seedlings with very different number of branches are likely to be identified in each combination. The analysis of variance for GCA and SCA has emphasised the fact that, in the studied apple combinations, both effects of general and specific combining ability contributed to the phenotypic expression of number of branches per tree. Goldenspur showed negative value for GCA, thus this could produce descendents with low vigour and number of branches, if they are used as genitors in apple breeding. Based on the values of general combining ability (GCA) and specific combining ability (SCA) selection of genitors can be very efficient for desirable characters of growth in apple breeding.

Several traits of growth on greenhouse carnation were analysed at seven varieties, growing both in vivo and in vitro. In vitro culture, proliferation and root formation were more intense in Pink Sol, Caribe and Tanga than in Pink Sim, Obor and Domingo cultivars. The highest intervarietal variability, under in vivo conditions, was recorded for the number of flowers per plant and number of petals per flower, while in vitro all analysed characters showed an extremely large span of variability values (s% = 26.5 - 109.1). The heritability in broad sense showed high values for the analysed characters, both in vivo (H2 = 0.548 - 0.992) and in vitro (H2 = 0.688 -0.953) conditions. There has been noted a tight positive and negative correlation among a lot of the traits of plants, both in vivo and in vitro. Correlations among the desirable traits can be used as selection indices, in carnation breeding.

Yield stability in sweet corn and its dependence on G x E interaction were investigated in a series of two way experiments. Five Romanian sweet corn hybrids were tested in three years (2008-2010) in three locations of Central Transylvania in different soils and climatic conditions. The experiments were organized in a split plot design in which, on a general level of organic fertilization (40 t/ha manure), four levels of mineral N fertilization were applied (kg/ha, active matter): N0, typical for organic technologies; N50, corresponding to the low-input (sustainable) system; N100 and N150 customary with conventional system of agriculture. Based on ear yield data registered for hybrids in locations x years x cropping system, a phenotypic index (Pi) was computed for each sweet corn hybrid illustrating the stability of their cob yields, with and without husks. The share of genotypic and G x E effects in the total value of Pi have been estimated. In different agricultural systems the tested hybrids were classified differently based on their Pi values. It is concluded that, at least for the time being, the initiation of an organic breeding program for sweet corn, in Romania, is not economically justified since all semiearly and semilate tested hybrids yielded satisfactorily under organic agricultural practices. Moreover, among the recently released sweet corn hybrids one can find certain genotypes highly suitable to organic (i.e. ‘Deliciul verii’, ‘Estival’) or low input (‘Dulcin’, ‘Estival’) agricultural practices. These three hybrids recorded the highes ear yields (with and without husks) over years, locations and agricultural systems.

A melon genomic library was used to isolate and characterize a clone of genomic DNA coding for ascorbate oxidase (AO) which is considered a key enzyme in the biodegradation of ascorbic acid (AA). The screening of genomic library was performed by using two probes: AO-PCR product and αE/CMAO3. Seven clones of recombinant phage, with positive signal, were isolated. The extracted DNA was digested with EcoRI, Sal I and Bam HI and the combinations among these restriction enzymes. Four clones of AO gene were isolated: AO1; AO2; AO3 and AO4. Since only clone AO4 had not been characterized so far, the sequencing of this clone was performed. The isolated sequence of DNA has a length of 3072 bp being bordered at both ends by EcoRI enzymes. The comparison between genomic DNA for AO4 in melon and DNA for AO in cucumber revealed a high similarity (94.45%).

In Romania, in this rather long period of transition, there are still many fruit tree orchards with old (classical) varieties which do not entirely meet the nowadays market and consumers criteria. Since these orchards cannot be replaced overnight, in this study it have observed the main yielding and quality characteristics of several well known apple varieties grown in Central Transylvania (Romania), in order to preserve the germplasm and evaluate the possibility to grow some of the best ones for particular or spot markets. According to data registered in this orchard, Jonathan had the most vigorous growth, expressed by the crown and trunk diameters, while Starkrimson had the weakest vigour. The largest fruits were found in Golden Delicious (186.5 g) and the smallest fruits in Jonathan (117 g) and Wagener (119 g). The highest fruit yield was harvested in Wagener (60.0 kg/tree), while the other classical varieties (Jonathan, Kaltherer Bmer, Starkrimson) yielded significantly less than the mean of experiment. The yield index (fruit yield/trunk section area) was comprised between 0.251 kg/cm2 in Wagener and 0.099 kg/cm2 in Jonathan. Fruit quality was very good in Kaltherer Bmer and Jonathan, good in Golden Delicious and accepTab. in the other two tested varieties. It can be concluded that valuable growing, yielding and fruit quality characteristics can be found in these old apple varieties which make them attractive both as germplasm sources and as commercial varieties for particular and spot markets.

In eight hybrid combinations in which one of the parents (either maternal of paternal) was cv. Pink Traminer (Gewurztraminer), 2.284 F1 individuals have been analyzed concerning the maturity of grapes. Obvious differences were noted among different combinations and within the same combination, depending on whether Pink Traminer had been used as a maternal or paternal genitor. These data suggest a possible maternal effect on the analyzed characteristic. Grape maturity seemed to be polygenicall inherited, heritability (in broad sense) showing high values while the one in narrow sense small and very small values, suggesting that additivity is not playing the most important role in the inheritance of this character in grapes.

The architectural ideotype - type of growing - was studied in a topcross experiment with five hybrid combinations in which Cluj 72-2-100 selection, typical spur, was used as a maternal tester. The analyzed seedlings were at the end of their sixth year of vegetation. There were no significant differences among the five hybrid combinations concerning the distributions of F1 seedling in the four accepted ideotypes (columnar, spur, standard, and weeping). A high variability was found for ideotype (between 18.8% in Cluj 72-2-100 x Napoca and 34.4% in Cluj 72-2-100 x Red Bartlett). The participation rate of genotype in the phenotypic manifestation of this character is relatively low. The coefficient of heritability in broad sense was 0.29 and the coefficient of heritability in narrow sense was very low, 0.001.

1656 F1 hybrid apple seedlings, belonging to 127 combinations, have been screened according to their growing and fruit setting types, as it was phenotypically expressed. LESPINASSE (1977; 1992) amalgamated these two traits into a single one which was named ";ideotype";. The screened F1 individuals have been considered as resembling one of the following four architectural ideotypes of the trees indicated by Lespinasse: columnar, spur, standard and weeping. Different ratios of spur, standard and columnar F1 individuals were obtained depending on genitors and on the fact that a certain genitor had been used as a maternal or paternal partner in direct/reciprocal crosses. The monogenic inheritance of the columnar ideotype, proposed by Kelsey and Brown (1992); Lane (1992), does not seem to be the only genetic mechanism involved in the inheritance of this trait. Our experimental results suggest the polygenic determination of this ideotype as more probable than the monogenic one.

A new variety of tetraploid red clover "Dacia-Tetra" released at Cluj by the breeding team of Prof. dr. M. Savatti, is characterized in the paper. Detailed morphological and physiological traits of the new variety, presented together with its yielding characteristics and biochemical properties of yield (green and dry matter) intend to individualize this new red clover variety among other domestic and foreign cultivars of this species. Obviously, the new tetraploid clover variety "Dacia-Tetra", due to its high yielding capacity (100-120 t/ha) and very good quality of fodder crop is recommended for all ecological zones of red clover in Romania.

Roxana is a synthetic red clover variety, made up of fourteen families. It was obtained by the breeding team of Prof. dr. M. Savatti and released as a new variety in 1995. Roxana is 3-5 days earlier than Select 1, has a very good yielding capacity in the second year and a satisfactory one in the third year of vegetation. Raw protein yield is 8% higher than in Select 1 while seed yield exceed that of Select 1 with 15.3-35.3%. It is recommended mainly in Transylvania where it meets the most favourable ecological conditions.