Variability of decorative traits, response to the Aphis fabae attack and RAPD diversity in different genotypes of Calendula

In order to identify cultivars with special decorative value and potential genitors for breeding process, 45 genotypes of Calendula genera were analyzed, belonging to six species: C. officinalis, C. alata, C. arvensis, C. stellata, C. suffruticosa and C. tripterocarpa. The average height of plants varied strongly, from 22.0 cm (C. officinalis cv. Rozovyi Sjurpriz) cm to 84.1 cm (C. tripterocarpa Rupr.). The lowest number of branches per plant was recorded on C. arvensis F. (4.6) and the largest one on C. officinalis LDA (16.4). The average number of flowers per plant ranged from 98.0 (C. suffruticosa Valh.) to 2.0 (C. officinalis UK). From among all genotypes, aphids (Aphis fabae) have attacked 19 (42.2%), and the results showed that AD% (Attack Degree) depend significantly on genotypes. RAPD analysis and phylogenetic dendrogram illustrated the relationship between genotypes and DNA polymorphism exists between the six species. Were found not only close phylogenetic links among cultivars apart of the same specie, but also between different species. C. officinalis A., C. alata UK and C. suffruticosa formed a subgroup similar to the molecular level, but also confirming some phenotypic similarities, these species having the smallest number of petals in the corolla and the highest sensitivity to Aphis fabae attack. The large variability identified in Calendula genotypes allows the selection of potential genitors for new breeding works, with appropriate decorative characteristics and resistance to aphids attack. RAPD analyses and phenotypic study allows hypothesis regarding the success of intra- and inter-specific hybridization, thus facilitating Calendula breeding processes

New Products against Apple Scab and Powdery Mildew Attack in Organic Apple Production

Interspecific hybridizations represent one of the apple breeding methods by which a wide variability can be achieved, useful for creating new cultivars. The study of 2190 interspecific hybrids, obtained from 25 combinations among crab apple species (Malus coronaria, M. floribunda, M. niedzwetzkyana, M. zumi, M. prunifolia) and different apple cultivars, points out a large variability of the F1 seedlings for several traits, with significant importance in apple breeding programs. The first year of fructification, as mean per hybrid combination, varied from 6 (M. zumi x ‘Jonathan’) to 9.3 years; the average hybrid’s age for fructification was 7.4 years. The size of fruits among families varied from 1.5 (‘Starkrimson’ x M. prunifolia) to 4.0 (‘Reinette Baumann’ x M. zumi), the mean being settled at 2.8 (therefore below mark 3, meaning ‘small fruits’). The lowest infection rate both for apple scab and powdery mildew attack was noticed at hybrids from M. coronaria x ‘Reinette Baumann’. On the whole, the hybrids with genitors of ‘species x cultivars’ type have had an early fruiting and a better resistance to scab and powdery mildew, compared to the ones from ‘cultivars x species’ combinations. The large variability of the studied traits gave the possibility to identify offsprings with desirable characteristics on nine hybrid combinations. Among these, 53 elite plants were selected, with a strength of selection of 2.42%, therefore a relative low value, correlated with the peculiarities of the interspecific population and the selection criteria for dessert apple