Volume 21 (2009): Issue 2 (December 2009)

The experiment was carried out in the years 2002-2004. Its aim was the determination of the tendencies in the microelement nutritional status of the standard cultivars of Anthurium cultorum Birdsey (‘Baron’, ‘Choco’, ‘Midori’, ‘Pistache’, ‘President’, ‘Tropical’ from Anthura B.V.) in the autumn-winter and spring-summer vegetation periods. The plants were cultivated in expanded clay using a drop fertigation system with standard nutrition. A significant influence of the vegetation periods and the light conditions associated with them was found to be exerted on the microelement plant nutrition. In the autumn-winter period, characterized by light deficit, the plant age significantly modified the nutrition (increase or decrease of content with a plant’s aging) with regard to zinc (-23.7%), copper (-25.8%) and boron (+25%), while in the spring-summer period, iron (+12.9%) and copper (-21.7%) nutrition was modified. During the three years of the study, the autumnwinter period showed a significant increase of iron content (+9.8%) with a simultaneous decrease of copper content (-6.5%), in comparison with the springsummer period. The awareness of the cyclical nature of the changes in the nutritional status of plants, depending on the given vegetation season, supplies a valuable instrument in the interpretation of plant analyses for diagnostic purposes.

The studies were carried out both in in vitro and in vivo conditions. The field experiment was conducted during the years 2005-2007 at the Experimental Station in Mydlniki, owned by the Department of Plant Protection at the University of Agriculture in Krakow. The aim of these studies was to determine the effect of tuber dressing and plant spraying with Polyversum (B.A.S. Pythium oligandrum) and Biochikol 020 PC (B.A.S. chitosan) bio-preparations on the top leaves and tubers of ‘Ibis’ potatoes infested by Phytophthora infestans. The chemical preparation Vitavax 2000 FS (B.A.S. karboxin and thiuram) was used. The in vitro evaluation of Polyversum and Biochikol 020 PC bio-preparations on the P. infestans mycelium linear growth was investigated. The above-mentioned preparations were applied at three different concentrations. The experiment was carried out using the Kowalik and Krechniak method (1961). Based on the results it was found that the preparations under examination significantly inhibited top leaf and tuber infestation by Phytophthora infestans. Moreover, according to the results obtained from in vitro tests, a significant effect from the Vitavax 2000 FS and Polyversum preparations and from the highest concentration (2%) of Biochikol 020 PC preparation on the percentage inhibition of P. infestans mycelium linear growth was observed (in comparison to the control).

The aim of the present experiment was to assess the influence of the method of cultivation and spacing on the market and nutritive quality of ‘Lord F1’ broccoli heads. The experiment was conducted at the University of Agriculture in Krakow, Poland, in 2002-2004. The method of broccoli cultivation (direct sowing or transplanting, and spacing: 20, 30, 40 and 50 cm × 67.5 cm) had no clear influence on the dry matter content in the heads. The mean dry matter content in broccoli heads was 9.5%, and reducing sugar was 1.12% of fresh matter. In 2002 and 2004, transplanting resulted in an increase of soluble sugar content as compared to direct sowing. The element content in broccoli was dependent mainly on the vegetation season, but in many cases directly sown plants had more phosphorus, potassium, calcium, and magnesium. With the increase of spacing in rows the content of some elements (P, K, Ca, Mg) in broccoli heads rose in the first year of the experiment. The mean content of elements found in broccoli heads was as follows (in mg kg^-1 of dry matter): phosphorus 6001, potassium 23447, calcium 3696, magnesium 1583, and iron 66.7.

This study presents the influence of major weather factors during the blackcurrant blossoming period on the yields of the ‘Ojebyn’, ‘Titania’ and ‘Roodknop’ cultivars, cultivated in Warmia (Olsztyn). The study was conducted for five years (2003-2007). Among the factors analysed were the currant yield, the duration of the blossoming period, average daily air temperature, the number of days with frost at the height of 2 m and at the ground level, total rainfall during the blossoming period and the number of days with rainfall during the blossoming period.

The statistical analysis of particular weather factors has shown that the number of days with frost contributed significantly to the yield of the fruit. A linear correlation analysis has shown that the yield of the three examined cultivars of blackcurrant depended on variable weather conditions during the blossoming period. The yield of the ‘Ojebyn’ cultivar was significantly correlated with the duration of the blossoming period, the number of days with frost and the number of days with rainfall. A significant correlation in the ‘Titania’ cultivar was found with the number of days with frost and with the total amount of rainfall during the blossoming period. The fruit yield from the ‘Roodknop’ cultivar in the five-year period under study depended only on one variable: the duration of the blossoming period. The highest yield was obtained from the ‘Titania’ cultivar.

In this study, the influence of gibberellic acid (GA₃) on strawberry in vitro shoot culture growth and development was investigated. ‘Senga Sengana’ and ‘Elsanta’ clones were grown on the medium recommended by Boxus (1999), supplemented with BA (0.5 mg dm^-3), IBA (0.1 mg dm^-3), glucose (40.0 g dm^-3) and GA₃ (0.1 - control, 1.0, 2.0, 5.0, 10.0 mg dm^-3). In general, gibberellic acid improved axillary shoot elongation and reduced the growth of callus as well as the formation of roots and the development of adventitious shoots. GA₃ applied at a concentration of 1.0-2.0 mg dm^-3 significantly increased the number of axillary shoots (mainly crown shoots), whereas under higher (5.0-10.0 mg dm^-3) doses it stimulated the development of runners. It seems that a new method of strawberry micropropagation based on the multiplication of axillary crowns and runners, which could also reduce the risk of domination of in vitro cultures with adventitious shoots, might be elaborated

A quantitative assessment of the morphogenetic capability of strawberry was performed. In the experiment, three genotypes of strawberry Fragaria × ananassa Duch. were tested, including two cultivars: ‘Plena’ and ‘Kent’, and one breeding clone no. „394‟. Morphogenetic efficiency was expressed by the mean number of microplants produced by the explant of progeny combinations F₁ in two subsequent subcultures. Progeny F₁ was obtained after crossings, which were carried out according to Griffing's method 3, with the use of the parental genotypes given above. Quantitative parameters: combining ability and the effect of reciprocal crosses estimated in the progeny F₁ allowed to assess the genetic control of the analysed feature. The high positive effect of reciprocal crosses showed that in „Plena‟ the morphogenetic capability is genetically controlled mainly by nuclear genes. On the other hand, aspects of extranuclear inheritance of the analysed trait were observed in ‘Kent’, which proved a weak explant ability of the progeny combination F₁ to produce microplants. This resulted in the high negative effect of reciprocal crosses for that cultivar

The effect of foliar feeding with two fluid multicomponent fertilizers was investigated: Florovit and Ekolist Warzywa + Urea on the yield and quality of three medium-fruit-size melon cultivars (‘Charentais F₁’, ‘Melba’, ‘Fiesta’). Weather conditions in the consecutive years of the study had a significant influence on the yield level and quality of fruit. A higher yield of better quality was achieved in the years 2005 and 2007. That period was characterised by relatively high air temperature and low rainfall towards the end of the growing period of melon. The fertilizers applied in the experiment significantly influenced melon yielding. The plants fertilized with Ekolist Warzywa + Urea provided a higher marketable yield of melon fruit than the plants fertilized with Florovit. When applied, this fertilizer also caused an increase in flesh thickness and fruit flavour as compared with Florovit feeding. Foliar feeding with both studied patterns increased the average fruit weight and number of marketable fruit as compared to the non-fertilized treatment. Among the studied cultivars, ‘Fiesta’ gave the highest marketable yield and the best quality fruit.

Studies were carried out in the years 2006-2008 in Przybroda near Poznań. The objects of the studies included seven-year-old peach trees of the cultivars ‘Harnaś’, ‘Reliance’, ‘Vinegold’ and ‘Early Blaze’ nectarine. The trees were strongly damaged by frost during the winter of 2005/2006. In May 2006, intensive regenerative tree pruning was carried out. Two treatments were applied: 1. The control with no pruning treatment, where only sanitary pruning was performed; 2. Trees were pruned at the height of 1.5 m and the shoots, which were developing below that height line, were left not pruned. The pruning treatment caused the development of an abundant number of longshoots, which are valuable for fruiting, in the central part of the crowns, with a diameter greater than 0.5 cm in comparison with the control trees. In the second year after pruning, spring ground frost destroyed the flowers and fruit buds and only single fruits were harvested. In the third year after pruning, the trees bloomed very abundantly and set fruits, therefore thinning was necessary. The yield was high and in most cases, it was equal independent of the tree pruning method, giving up to 18-19 kg per tree. Differences occurred only between the particular cultivars where the yield oscillated between 11 and 25 kg per tree. The best yielding was shown by ‘Vinegold’ (over 24 kg), then ‘Harnaś’ (21 kg), while the poorest yield was obtained from ‘Reliance’ (about 11 kg).

The goal of this three-year study was to develop a quarantine-like treatment for two commercial sweet pepper (Capsicum annuum L.) cultivars, based on physical treatments and packaging materials, and to understand, in part, the chilling resistance-mode-of-action.

This research has revealed that individual shrink packaging following prestorage-HWRB treatment, significantly reduced chilling injuries and chilling severity, as shown by very low percentage of CI and a very low CI index, while maintaining a good overall quality (less decay incidence and weight loss) after 21 d at 1.5°C plus 3 d at 20°C (sea transport to USA and Japan from Israel + marketing simulation).

The chilling injury reduction is mainly due to a significant water loss reduction by the shrink film, while HWRB treatment contributed mainly to a significant decay reduction, and to some degree of inhibition of chilling development. Cultivar ‘Selika’ was found less susceptible to chilling then cultivar ‘7158’.

Trees play a crucial role in the urban environment. They fulfil aesthetic, sociocultural, ecological, health-promoting and economic functions. Urban development and related human activity bring many risks to green areas within urban space. Plants are exposed to stress connected with water, soil and air pollution. Living space, harmful light and thermal conditions, drought, high density and changeable soil pH with excessive salinity are further disadvantages. European and Northern American cities have to cope with a serious danger of tree death. A leading cause is the use of de-icing chemicals in winter, particularly sodium chloride, applied due to its cost-effectiveness and availability. The paper describes traditional de-icing chemicals used in urban areas (NaCl, solid aggregates, CaCl₂, MgCl sulphates MgSO₄, (NH₄)₂SO₄, urea alcohols and glycols isopropyl alcohol, ethylene glycol, methanol) and newly developed sodium chloride substitutes (calcium magnesium acetate CMA), sodium formate and acetate NaFo/NaAc, potassium carbonate K₂CO₃). Moreover, prophylactic methods aimed at preventing the negative impact of de-icing campaigns, rules of planning and design of urban landscape, and reasonable management measures and pro-ecological modern technologies reducing and reversing the consequences of harmful actions are presented