Volume 21 (2009): Issue 1 (June 2009)

Among all elements taken into consideration in this research (Al, As, B, Ba, Be, Bi, Ca, Co, Cr, Fe, Ga, In, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, Sr, Ti and V), only the concentration of Na in the ‘Kazan F1’ carrot was affected by the interaction of foliar application and nitrogen fertilization. In the case of plants fertilized by Ca(NO₃)₂, foliar application significantly raised Na concentration in storage roots. Compared to the control, all applied nitrogen fertilizers (results analysed independently from the foliar application factor) increased concentrations of Mg and Se in carrot. Fertilization with (NH₄)₂SO₄ resulted in a decrease of Ba and Mo concentrations and an increase of Mn concentration, while fertilization with Ca(NO₃)₂ raised the contents of Sr and Be in carrot. Foliar application (analysed independently from nitrogen fertilization) considerably increased Bi and Be concentrations, yet it did not affect the contents of other elements in storage roots.

Studies upon the ‛Epic F₁’ eggplant were carried out in 2004 − 2005 in an unheated plastic tunnel. The eggplant was cultivated in cylinders made of rigid foil of 10 dm³ capacity each filled with horticultural peat in 0.6 × 0.5 m spacing. The experiment consisted of two factors in a complete randomized design. The influence of the following factors was examined: 1 - potassium fertilizer kind (KCl, K₂SO₄, KNO₃); 2 - potassium dose (8, 16, 24 g K per plant). Fruit samples were harvested for laboratory analyses in the middle of August in the middle of the fruiting period. Fruits were harvested every 7-10 days at the stage of utilization maturity. Total and commercial yields as well as the number of fruits per 1 m² were evaluated. Fresh fruits were subjected to the following analyses: dry matter - drying method, vitamin C - Tillmans’ method, and sugars - Schoorl-Rogenbogen’s method. The obtained results were subjected to analysis of variance. Different potassium fertilizers did not significantly influence yield size and structure as well as eggplant fruit number. The highest fruit yield was obtained from plants fertilized with potassium in the form of KCl at the largest dose of 24 g K per plant. No effects of potassium doses in a form of K₂SO₄ and KNO₃ on eggplant yield were observed. Instead, significant influence of varied potassium fertilization on the fruits’ biological value was found. Potassium added in a form of KNO₃ at a dose of 8 g K per plant resulted in the highest dry matter and vitamin C content in eggplant.

In the years 2002 − 2004 research was carried out on the effect of onion (Allium cepa L.) ‘Wolska’ bulb size on selected morphological characteristics of seed stalks, seed yield and quality. Commercial bulbs (vernalised, one-year-old mother bulbs) were divided into three groups: small, medium and large, with diameters of 4.2-5.3 cm, 5.4-6.3 cm and 6.4-8.5 cm, respectively. Then, the bulbs of each group were planted in the field and grown routinely with the purpose of producing seeds. The following characters were measured on the seed stalks: number and height of seed stalks grown out from one bulb, the seed stalks’ diameter at the height of 10 cm above the ground, the diameter of the inflorescence, seed yield from a single stalk and from the entire plant, the weight of 1000 seeds, number of seeds in 1 g, length and width of the seeds, length and width of the embryos, and germination energy and capacity. Our experiments showed a significant influence of bulb size on the number of seed stalks and the inflorescence diameter. It was discovered that the big bulbs gave larger numbers of seed stalks than the seed stalks grown from the medium and small ones. Small bulbs gave seed stalks with smaller inflorescences than the medium and large ones. The bulb size had no effect on the seed stalk height or their diameter when measured at the level of 10 cm above the ground. The bulb size also did not affect seed yield per one seed stalk, but it did affect the seed yield obtained from the entire plant, which was bigger for plants grown from large bulbs in comparison with the small ones. The size of the bulbs had no effect on either the weight of 1000 seeds or the number of seeds in 1 g. It did not affect either the seed and embryo length and width or the seed germination energy and capacity.

In a potted experiment the influence of foliar application of triacontanol (TRIA) at the concentrations of 0.01; 0.10; 1.00 mg dm^-3, and Asahi SL at the concentrations of 0.1; 0.2; 0.3% on the growth and yielding of plants was studied. Electrolyte leakage, water saturation deficit, contents of proline and chlorophyll a + b in leaves, as well as the maximum quantum efficiency of chlorophyll (F_v/F_m) and gas exchange in plants which were treated for five days in temperatures of 15/7°C (day/night) were also examined.

The achieved results showed that periodic chilling decreased the value of all the analysed parameters of the plants to a significant degree, with the exception of electrolyte leakage, water saturation deficit and proline content, whose values under these conditions increased. Triacontanol and Asahi SL favourably influenced both the plants treated and not treated with periodic chilling, but the effect of biostimulators on plants treated with chilling stress was clearly higher. The negative influence of chilling on the plants of Ocimum basilicum L. was decreased by TRIA in the concentration 0.10 mg dm^-3, and by Asahi SL in the concentration of 0.2 and 0.3%.

In order to determine the effect of temperature on asparagus yielding in the case of different crown sizes, asparagus plants were planted in growth chambers, in an aeroponic system with recirculation. The results show that asparagus yield was dependent on air temperature and crown size; however, crown size had a greater influence on the yield. The diameter and weight of the asparagus spears were also dependent on crown size. Higher dry weight content, degrees Brix, fructan and total carbohydrate content in storage roots were documented in large crown asparagus plants before and after harvest. Large sized crowns were also shown to build thicker and higher ferns.

Pot experiments conducted in a growth chamber studied the effectiveness of foliar fertilization of spinach (Spinacia oleracea L.) with macro- and microelements in the form of a 1% water solution of Insol U fertilizer applied with fluorescent light of the PAR intensity of 200 μmol m^-2 s^-1 and with dispersed daylight of the intensity of 600 μmol m^-2 s^-1. Insol U was applied three times, supplied on the upper, lower or both sides of the leaf blades. The control consisted of plants sprayed with distilled water. The obtained results pointed out that foliar fertilization of spinach with Insol U significantly increased the leaf gas exchange, the yield of the fresh leaf mass, the content of vitamin C, chlorophyll, carotenoids, as well as potassium and phosphorus in the leaves. The application of the fertilizer onto the upper and the lower side of the leaf blade had the most positive effect on the analysed property of the leaves. Independently of the side leaf, the application of the fertilizer at a higher light intensity had a significantly better consecutive effect on all the analysed properties of the leaves.

In this experiment, the growth of peach and nectarine trees was determined to be related to the cultivar. ‘Inka’ peach trees grew weaker than ‘Harbinger’ trees. The ‘John Rivers’ nectarine was characterized by stronger growth than the ‘Harko’. The amount of crops produced by the trees was related to the cultivar and the meteorological conditions during winter and spring. ‘Inka’ produced higher yields and bigger fruits as compared to ‘Harbinger’. The ‘Harko’ cultivar provided significantly higher yields than the ‘John Rivers’ only in 2006. Peach and nectarine fruit production in the Sandomierska Plateau in the years 2004 − 2007 was risky. In 2006, damage to the flower buds during winter caused no crop yield in young peach trees and the older ones of the ‘Harbinger’ cultivar. A minor reaction to the temperature drop, down to -26.8oC, was found for nectarines in comparison with peach trees. In 2007, the spring frost injured flower pistils and caused a lack of crops from the studied cultivars.

The aim of the research, which was carried out in the years 2002 − 2004, was the determination of the natural tendencies in the macroelement nutritional status and in the yielding of the standard cultivars of Anthurium cultorum Birdsey (‘Baron’, ‘Choco’, ‘Midori’, ‘Pistache’, ‘President’, ‘Tropical’ from Anthura B.V., the Netherlands) in the autumn-winter and spring-summer vegetations periods. The anthurium was grown in expanded clay with the use of standard nutrients in a drip fertigation system. It was found that an improvement of light conditions caused a significant increase in plant yielding. During the three years of the study, it was found that an essential influence was exerted by the vegetation period on the amount of phosphorus and potassium in the plants’ leaves. In the spring-summer period, a considerable decrease of phosphorus content in the plants was observed, but at the same time, there was an increase of potassium content. In the springsummer period, plant age affected the phosphorus and calcium content of the plants, while in the autumn-winter period, the phosphorus, potassium and calcium content was affected. A decrease in calcium, nitrogen and magnesium content was found in the spring-summer period, while the content of sulphur tended to increase. The obtained results could be a valuable instrument for the interpretation of index parts of plant analyses for diagnostic purposes.

In 2003 - 2005 the impact of intercropping white cabbage ‘Bently F1’ with French Marigold (Tagetes patula nana ‘Kolombina’) and Pot Marigold (Calendula officinalis ‘Promyk’) on the occurrence of pest insects was estimated. On plots where cabbage was intercropped the number of cabbage aphid Brevicoryne brassicae L. and flea beetles Phyllotreta was significantly lower when compared with control variant (homogenous crop). Intercropping had an effect on the butterfly oviposition too. The lower number of eggs of the small white butterfly Pieris rapae L., large white butterfly P. brassicae L., cabbage moth Mamestra brassicae L. and larvae and pupae of the diamondback moth Plutella xylostella L. were observed on plots with Calendula and Tagetes. Intercropping with Pot Marigold was the most effective pest control on cabbage.

For two years (2006 − 2007), seedlings and young plants of Helleborus lividus Aiton were grown in containers with a peat substrate, which was deacidified with calcium carbonate at the following doses: 2.5, 5.0, 7.5 and 10.0 g dm^-3. The plants were divided into two groups in each variant of CaCO₃ dosage, one fertilized with a solution of a lower (0.1%) and the other with a higher (0.3%) concentration of Peters Professional PL Special (15:11:29). Helleborus lividus growth in the first year of cultivation depended on the calcium carbonate dose. Taller plants, with a higher number of leaves, were produced using calcium carbonate at a dose of CaCO₃ 2.5-5.0 g dm^-3. In the second year of cultivation good quality plants - taller, with higher numbers of leaves and shoots, were produced when grown in a substrate with 2.5-7.5 g CaCO₃ per dm³. The application of solutions of various concentrations in top dressing did not have an effect on the growth of Helleborus lividus in the first year of cultivation, while in the second year taller plants, with more leaves as well as flowers and buds, were produced when applying a 0.3% fertilizer solution.

The research was carried out in 2005 − 2007 in the area of the Kórnik Arboretum and covered parasitoids of the Pimplinae, Poemeniinae and Diacritinae (Hymenoptera, Ichneumonidae) subfamilies, which control a number of plantdamaging phytophages. The quality and quantity composition of the parasitoids was defined, and the characterization of Pimplinae communities was carried out on the basis of the following biocenotic indices: Shannon’s diversity index H’, Pielou’s evenness index J’ and Simpson’s diversity index d. The Pimplinae communities were compared in terms of quality using the method of the Marczewski-Steinhaus MS index. Thirty-one species of Pimplinae were found; they account for 23.3% of the national fauna and 43.0% of species reported for Wielkopolska. Three species of Poemeniinae and one species of Diacritinae were also found. Among Pimplinae the prevailing species were those which decrease the number of pests belonging to exo- and endophytophages of Micro- and Macrolepidoptera. The dominants were: Pimpla contemplator (Muelle.) − 24.9%, Pimpla flavicoxis Thoms. − 12.3%, Pimpla insignatoria (Grav.) − 9.1%, Itoplectis maculator (F.) − 6.3% and I. alternans (Grav.) − 5.9%. Poemeniinae included Poemenia brachyura Holmgr. and P. herctica (Grav.), belonging to parasitoids of xylophages. Diacritinae were represented by Diacritus aciculatus (Voll.), whose trophic links are not yet known.

Experiments were carried out to evaluate the reaction of cabbage cultivars to mechanical inoculation with selected isolates of the turnip mosaic virus (TuMV). Simultaneously we aimed for the assessment of TuMV pathogenicity towards cultivars chosen to be transformed in order to obtain the resistance trait. The TuMV-CAR37A and TuMV-CAR39 isolates from horseradish proved to be infective towards ‘Amager’ and ‘Langedijker’ B. oleracea subsp. capitata f. alba. The course of symptom expression was assessed and the results of virus detection in symptomless leaves, using DAS-ELISA, were documented. Both tested cultivars showed a similar level of susceptibility. TuMV-CAR37A and TuMV-CAR39 can be useful in the selection of cabbage lines with resistance to the turnip mosaic virus.