Search

Tomatillo (Physalis ixocarpa Brot.) grows in Poland much like in Mexico although its development cycle is much longer and lasts 6 months. It was sown at the beginning of April in a heated greenhouse, and transferred later on to a heated plastic tunnel. It was transplanted to a field about May 20 when danger of frosts had passed. Three local cultivars of Mexican origin were used and are briefly described. Their vegetative growth characteristics in Poland were similar to that of cv. Rendidora, which was described earlier in Mexico. The tomatillo internodes and leaves became progressively smaller with age. Tomatillo leaves and fruits were not attacked by Phytophthora infestans in the field and laboratory. Inoculation with tomato strains of this disease was without effect.

A parthenocarpy-inducing preparation, Betokson, containing beta-naphthoxyacetic acid (NOA) as an active ingredient, was applied by spraying whole plants. As one of the controls, dipping the trusses in NOA solution was used according to a currently recommended technique. NOA applied by each of these treatment increased the very early yield (first 4 pickings) by 4-11 times in cv. Venture and 3-4 times in cv. New Yorker in comparison with the untreated controls. Treating the whole plant increased the very early yield more than did dipping the trusses. The early yield (first 8 pickings) was also increased in cv. Venture by NOA applied by both methods. Treatments with NOA decreased, however, the late yield. This decline was more marked with the higher NOA concentration and when the whole-plant-spray was applied. Gibberellic acid (GA3) applied alone as a whole-plant-spray at a concentration of 25 mg·dm-3, did not increase the very early yield but in combination with NOA, increased the early yield in cv. New Yorker. GA3 alone, or in combination with NOA, applied as a spray on the whole plant caused marked chlorosis of the leaves and marked decline of the total yield.

The following substances were used to defoliate apple rootstock instead of hand defoliation before digging out: KI, CuSO4 · 5H2O, Mg(ClO3)2< · H2O, ethephon (Ethrel 68-250 and CKB 1131), preparation N252, and the mixtures: ethephon (Ethrel) with copper sulphate, or with gibberellic acid, morphactin (EMD) with ethephon, and morphactin with ethephon and copper sulphate. Among the inorganic defoliants tested, only Mg(ClO3)2 · H2O gave satisfactory results in defoliating apple rootstocks. When applied at the end of September this chemical did not decrease winter hardiness of the rootstocks. Ethrel and the preparation CKB 1131,caused satisfactory defoliation, but when used in optimal concentrations for defoliation they decreased the winter hardiness of plants. The mixture of ethephon with copper sulphate in which both components were used in low concentrations also appeared highly effective. Ethephon in low concentration mixed with EMD caused only partial defoliation of the rootstocks. Addition of gibberellic acid did not improve the effectiveness of ethephon. Preparation N252 in a concentration of 0.15% effectively defoliated the rootstocks and did not cause a subsequent decrease of frost hardiness in the conditions of this experiment. The response of 'Jonathan' scions to defoliants was modified by the rootstock.

The husk tomato (Physalis ixocarpa Brot.) is widely cultivated in central Mexico, and may be grown in countries with a temperate climate. The experiment was set up during the dry period of the year (average weekly temperature 17-22°C) in the State of Morelos, Mexico, using the cv. 'Rendidora' in loamy clay soil and furrow irrigation. The roots were investigated by the pinboard method modified by Garcia Blancas and Grajeda Gómez (in print), partly adapted by us for quantitative estimation of root systems. Two plants were investigated every second week. They had a well developed tap root. Most of their lateral roots were found in the superficial soil layer, 0-20 cm. The root dry mass was also concentrated near the central axis of the plant. The majority of root apices were, however, found in the soil cylinders 10-40 em from the central axis. During the senescence of the aerial part (14th week after emergence) the root system lost a large part of its small roots. The modification of the pinboard method, by Garcia Blancas and Grajeda Gómez (in print) permited us investigating the root systems with very simple tools, in situ.

The reproductive development of tomatillo (husk tomato) was investigated in the conditions of central Poland. The developmental cycle of tomatillo in Poland lasts 20-23 weeks, including 6 weeks in a greenhouse or a tunnel and is longer than in Mexico (15 weeks). The plant grows well in Poland and is fruiting aboundantly. The cv. Rendidora B1 was early fruiting and sensitive to drought so it should be cultivated in a garden. Cvs Bujna and Antocyjanowa were medium late or late and suitable for open-field cultivation. Fruit development lasts about 6 weeks. Fruiting was concentrated on the apparent lateral branches of the 1st and 2nd order during the large part of a vegetative season. Among the abscised generative organs predominated flowers and at the end of vegetative season the flower buds. The maximum abscission of flower buds and flowers took place about 2-4 weeks after the most intensive flowering and fruit set. The fruits of many individuals are easily cracking. After being abscised they are attacked frequently by Botrytis sp.

NAA potassium salt (preparation Pomonit) applied at a concentration of 25 mg·dm;-3 markedly inhibited tipburn of internal leaves in lettuce plants grown in a greenhouse. Reduction of tipburn symptoms ranged from 9.6 to 96.9% depending on the cultivar. In the internal leaves, on which the disorder usually appears, the calcium level was generally lower and the level of phenolic substances higher. Treating the plants with a potassium salt of NAA, 2-3 weeks before harvest usually caused a rise of the Ca++ level and a decrease in the level of phenolic substances in the internal leaves. The NAA potassium salt was rapidly degraded in the plant and after only 24 hours was almost undetectable by a method sensitive to 0.3 µg NAA·g-1 fresh matter, therefore it is probable that NAA treatment may be permitted in practice.

The anatomical structure of pedicels of apple fruitlets was investigated. The fruitlets of cv. 'Mcintosh' and 'Bancroft' were collected on June 8th, 16th an 24th. The middle date coincided with the beginning of June drop. The pedicel structure of larger fruitlets which tended to be retained on the tree was compared with that of smaller fruitlets which tended to be shed of. In the pedicels of larger fruitlets, development of the xylem, especially secondary one, was more intensive. This difference increased in time. Lignification of cortex sclereids, phloem fibers, xylem parenchyma cells and pith cells was also more advanced. The differences in the amount of phloem tissue between both kinds of fruitlets were not large but usually significant. The mentioned differences especially in pedicel xylem development are considered to be partly responsible for the fact that smaller fruitlets loose gradually their ability to compete for nutrients. This finally leads to their starvation and shedding.

Tomato seedlings in hotbed with Antywylegacz (chlormequat chloride) to suppress their excessive elongation before transplanting, were used. Their first 2-3 flower clusters were dipped in the field in Betokson (ß-naphthoxyacetic acid) to induce better early fruit set and the plants were sprayed with Ethrel (ethephon) just before the first fruits become pink, to stimulate earlier ripening and increase early yield. The experiment was carried out during 3 years with the cultivars 'Venture', 'New Yorker' and 'Nesthackchen' (only in 1975). Application of chlormequat alone prevented excessive growth of the seedlings but did not increase early yield significantly. ß-naphthoxyacetic acid alone was effectiveevery year and always increased early yield. Chlormequat followed by ß-naphthoxyacetic treatment showed always a tendency to increase early yield more than ß-naphthoxyacetic acid alone. Treatment with ß-naphthoxyacetic acid, alone or in combination with other treatments, lowered the total yield. Ethephon used solely or in combination with other treatments usually was ineffective.

In a commerical orchard of 18-year-old trees, 1250 fruits were chosen for observation. The majority of them abscised during the first weeks after anthesis. Afterwards, the abscission gradually descreased, however, in the meantime three additional waves of more intensive shedding occurred which were best visible when the Relative Abscission Rate (RAR) was calculated. The peaks in the RAR curve were preceded by a decrease in the Relative Growth Rate (RGR) of persistent fruits, which suggests that nutritional or other stresses occurred in the whole branch. In the period from May 15th to July 15th, predominantly the smaller fruits were abscised, later on, however, fruits of the same size as the persistent ones were shed. The formula for calculating RAR and RAR is shortly discussed.

The architecture of the tejocote (pronounciation: tehocote) - a Mexican fruit trees is described. There is a great morphological diversity among the tejocote clones growing in Germplasm Bank of the Autonomic University of Chapingo, Mexico. The common character of all hawthorns in this bank is that the inflorescence axis dies after shedding the reproductive parts (flowers or fruits) but remains on the tree, and the growth continues from the bud situated below the dead part. The growth and ramification habit were described as long shoots showing marked apical dominance and as the complex of shoots showing week apical dominance. The non-pruned trees of tejocote clones used as fruit trees form strong natural crown. The architecture of it is similar to the “Troll’s model” of Hallé and Oldeman (1970). Metamorphosis and reiteration are relatively frequent. The inflorescence structure was described, as well as the types of thorns in clones, which have thorns. Tejocote hawthorn may probably be an interesting fruit tree for countries with warm climate and a long dry period. It is also well adapted to shallow calcareous soils.

Road transport is one of the most important factors for the national economy due to its universality and comprehensive possibilities of transporting people and goods. Unfortunately, from the energy point of view, it is also the most cost-intensive and has a negative influence on the natural environment. For these reasons, issues related to limiting the use of conventional fuels are very important, which results in reducing emissions from this sector, as well as reducing transport costs. This article presents currently used energy sources for propulsion of road vehicles, including fossil and alternative fuels, gaseous fuels and other energy sources such as fuel cells. The following section presents technologies that allow to recover some of the energy lost in motor vehicles and internal combustion engines used for their propulsion. The principle of operation of these solutions, their structure and their main features are presented. The last part focuses on discussing and identifying the most universal technologies for energy harvesting in vehicles and showing further directions of energy development in the automotive sector. [ABSTRACT FROM AUTHOR]

The study aims to verify the relationship between the unemployment rate and economic growth in European Union (EU) regions. As the most important macroeconomic relationship, the significance of the dependence between the labour market situation and the output growth is widely known and considered. Analysis in this research was conducted using data for 229 EU regions on the NUTS-2 level in the years 2013-2019. In order to verify the relationship between the unemployment rate and the output growth, the spatio-temporal models for pooled time series and cross-sectional data (TSCS) were estimated. The Fitted Trend and Elasticity Method of verifying Okun's law was used in the analysis, wherein the deterministic trend factor was enriched with the spatial element. Educational attainment as the additional explanatory variable was included in the models. The neighbourhood between regions was quantified based on two criteria: (1) common border criterion - related to the possibility of population migrations, and (2) similarity of the unemployment rate criterion - related to the imitation effect in the issue of introduced rules and regulations on the labour market by regional governments. One of the hypotheses verified in the investigation is the superiority of the economic neighbourhood over the geographical neighbourhood. [ABSTRACT FROM AUTHOR]

The rapid growth of the human population in recent decades has resulted in the intensive development of various industries, the development of urban agglomerations and increased production of medicines for animals and humans, plant protection products and fertilizers on an unprecedented scale. Intensive agriculture, expanding urban areas and newly established industrial plants release huge amounts of pollutants into the environment, which, in nature, are very slowly degraded or not decomposed, which leads to their accumulation in water and terrestrial ecosystems. Researchers are scouring extremely contaminated environments to identify organisms that have the ability to degrade resistant xenobiotics, such as PAHs, some pharmaceuticals, plasticizers and dyes. These organisms are a potential source of enzymes that could be used in the bioremediation of industrial and municipal wastewater. Great hopes are pinned on oxidoreductases, including laccase, called by some a green biocatalyst because the end product of the oxidation of a wide range of substrates by this enzyme is water and other compounds, most often including dimers, trimers and polymers. Laccase immobilization techniques and their use in systems together with adsorption or separation have found application in the enzymatic bioremediation of wastewater. [ABSTRACT FROM AUTHOR]

A chronosequence approach was applied to evaluate the effects of silver birch succession on soil organic matter (SOM). The studies covered five plots (arable field [AF], fallow [FA] and three birch stands aged 8, 33 and 40 years), and all located in the same complex of Brunic Arenosols in central Poland. The O and A horizons of the soils were sampled and analysed using the standard procedures in soil science. It was found that the birch succession was accompanied by dynamic changes in the stock and quality of the SOM. The transition from AF to FA soils did not significantly change the content or pool of SOM in the A horizon; however, it did modify its fractional composition and internal structure. This was reflected by an increase in the humic acids content and a decrease in the fulvic acid, as well as in the values of the elemental and 13C-NMR analyses. Rapid losses in the SOM content and stock in the A horizon were recorded after entering the silver birch. The soils under the young birches were characterised by lower contents of low-molecular humus fractions, which are more susceptible to microbial degradation, than the FA soils. In addition, the birch succession contributed to a lower internal oxidation of the humic acids and an increase in the content of aliphatic structures in their molecules. The next stages of succession were characterised by gradually increasing SOM contents and stocks, accompanied by the increasing internal oxidation and maturity of the humic acids. [ABSTRACT FROM AUTHOR]