Horticultural Science, 2011 (vol. 38), issue 3

Defensive reactions of apple cultivars Angold and HL 1834 after fungal infection

J. Schovánková, H. Opatová

Hort. Sci. (Prague), 2011, 38(3):87-95 | DOI: 10.17221/37/2010-HORTSCI  

Apple cultivars (Malus domestica Borkh.) were inoculated with a significant apple fruit fungal pathogen, Monilinia fructigena Honey ex Whetzel. Defensive reactions, especially enzyme activity and production of phenolic compounds, were compared. Changes of phenolic content and activity of phenylalanine-ammonia lyase (PAL) were determined 7, 14 and 21 days after the inoculation. Progress of rotting was similar for both cultivars at first but defensive reactions were different. The increase of phenolic compounds was observed; their concentration and composition were influenced by location in the fruit. A very good correlation was found...

Introgression of yellow flower colour in Buddleja davidii by means of polyploidisation and interspecific hybridisation

K. Van Laere, J. Van Huylenbroeck, E. Van Bockstaele

Hort. Sci. (Prague), 2011, 38(3):96-103 | DOI: 10.17221/61/2011-HORTSCI  

To introduce yellow colour in the commercial Buddleja davidii (2n = 4x = 76) assortment, an interspecific breeding programme with B. globosa (2n = 2x = 38) was started. The first step was to perform chromosome doubling in B. globosa. Two of the obtained tetraploid B. globosa plants were subsequently used as male parent in interspecific crosses with the white flowering B. davidii cv. Nanhoensis Alba. In total 182 interspecific crosses were made and 18 F1 hybrids were obtained. Genome size measurements, chromosome counts and genomic...

Chronological changes in plant hormone and sugar contents in cv. Ao-Shuang autumn flowering tree peony

P.M.P. Mornya, F.Y. Cheng, H.Y. Li

Hort. Sci. (Prague), 2011, 38(3):104-112 | DOI: 10.17221/11/2011-HORTSCI  

Successive secondary flowering is critical for tree peony industry. Varying the levels of hormones and sugars are reported to influence plant flowering. This study analyses quantitative changes in the levels of endogenous hormones [indole-3-acetic acid (IAA), abscisic acid (ABA) and gibberellic acid (GA₃)] and carbohydrates (sucrose, reducing sugar and starch) in the buds of cv. Ao-Shuang tree peony during autumn and spring flowering seasons. The study shows different levels of hormones (ABA, IAA and GA₃) and carbohydrates (sucrose, reducing sugar and starch) in spring (SFB) and autumn (AFB) flowering buds. Not only is there increase...

A preliminary proposal for an original classification of garden plants based on the study of their phenological periodicity and their side-runs

P. Bulíř

Hort. Sci. (Prague), 2011, 38(3):113-119 | DOI: 10.17221/32/2010-HORTSCI  

A model group of garden plants (shrubs) was used to observe and evaluate phenological periodicity and new ways of its practical use in landscaping. The experiment focused on the aesthetically most impressive phenophases - full bloom and full coloration, and was conducted in three independent and separate localities over a period of 4 years. While observing and evaluating the selected group of plants, we also monitored and recorded concurrent attractive phenological events in other garden plants, seeking to verify the existence of certain "vegetation waves". The experiment demonstrated that in the research localities the course of phenological periodicity,...

Flower thinning of apple cultivar Braeburn using ammonium and potassium thiosulfate: Short communication

B. Milić, N. Magazin, Z. Keserović, M. Dorić

Hort. Sci. (Prague), 2011, 38(3):120-124 | DOI: 10.17221/57/2011-HORTSCI  

Ammonium and potassium thiosulfate are used commercially or experimentally as flower thinners because they are considered user, environment and consumer safe. The thinning trials were conducted in 2009 and 2010, on three- and four-year-old Braeburn Mariri Red* trees. The chemicals were applied at 1%, 2% and 3% rates of ammonium and 0.5%, 1% and 1.5% of potassium thiosulfate. Both thinning agents reduced fruit set, but were more efficient in 2009, when applied at 20% full bloom, than in 2010, when they were applied at 80% full bloom. Flower thinning with ammonium and potassium thiosulfate increased the average fruit weight, but the highest chemical...