Rad opisuje način rada i opremu za endoterapeutsku metodu primjene sredstava za zaštitu bilja koja je razvijena za zaštitu visokih stabala od uzročnika bolesti i štetnika, a može se podijeliti na tri ...tehnike: zalijevanje tla, injektiranje tla i injektiranje debla. Injektiranje debla učinkovitije je i ekološki prihvatljivije od tretiranja tla. Najprikladnija tehnika jest injektiranje debla pod kontroliranim tlakom od 2,5-3,5 bara. Za uspjeh injektiranja vrlo je važno odrediti primjerenu koncentraciju škropiva, pri čemu treba uzeti u obzir da se niža koncentracija brže absorbira od više koncentracije. Također, stabla „mekoga" drveta usvajaju škropivo brže nego stabla „tvrdoga" drveta, a absorpcija škropiva brža je i za toplog i sunčanog vremena.
U radu je s ekonomskog stajališta ocijenjena primjena različitih sustava obrade tla u proizvodnji sjemenki bundeva. Testirana su četiri sustava obrade u proizvodnji bundeve austrijske sorte ...Gleissdorf. Sustavi obrade su bili: 1. Konvencionalni sustav (plug, tanjurača i kombinirano oruđe), 2. Konzervacijski sustav (rotodrljača), 3. Nulti sustav (no-till sijačica) i 4. Reducirani sustav (plug, kombinirano oruđe). Svi ispitivani sustavi su značajno iznad granice ekonomičnosti proizvodnje. Najbolji odnosi prihoda i troškova u proizvodnji sjemenki bundeve postignuti su pri sustavu konvencionalne (A) i reducirane obrade (D) a zatim slijede nulta (C) i konzervacijska (B) obrada.
Na lessive pseudogleju donje Podravine provedena su trogodišnja istraživanja osam različitih varijanata obrade u kombinaciji sa četiri varijante mineralne gnojidbe. U ovom se radu iznose rezultati za ...šećernu repu. Varijante obrade tla u kombinaciji s četiri razine mineralne gnojidbe (niska, srednja, visoka i vrlo visoka) bile su sljedeće: oranje na 20, 30, 40, 50 i 60 cm, te oranje na 20 cm s podrivanjem na 50 i 70 cm i oranje na 30 cm s podrivanjem na 50 cm. Druge i treće godine istraživanja pratio se rezidualni učinak duboke obrade i mineralne gnojidbe, pa su stoga oba zahvata bila uniformna. Duboka je obrada tla u pravilu pozitivno djelovala na prinos korijena šećerne repe i šećera. Gnojidba je u osnovi bila vrlo neučinkovita u sve tri godine, što posebno vrijedi za vi.e doze. U skladu s pojedinačnim djelovanjem obrade i gnojidbe tla, interakcijsko djelovanje oba čimbenika javilo se u ograničenom opsegu. Pri tome je značajniji bio kompenzacijski učinak obrade.
Open-air fires or forest fires are becoming a key factor in reducing the forest surface areas and they are one of the major factors of devastation and degradation of forests and forest land and their ...ecosystems in the Mediterranean, mainly in coastal karst. They cause extreme material and economic damage, and they negatively affect biological and landscape diversity. After the forest fire, significant quantities of fired trees are left behind, representing a significant amount of lignocellulosic biomass available for conversion into a variety of biobased products. The question arises as to what degree they are chemically degraded, or whether they still have the properties required for further application in mechanical or chemical processing. The main aim of this paper was to study the group chemical composition as a biomass chemical property of the Aleppo pine (Pinus halepensis Mill.) sapwood before and after the impact of low ground fire and high fire of the treetops at tree height of 0, 2 and 4 m. Therefore, the impact of forest fires on the Allepo pine sapwood group chemical composition was studied in terms of quality for further application in production of biorefinery products. In addition, research results on group chemical composition of the same unfired and fired Aleppo pine wood bark from previous study were used for comparison with sapwood from this study. The obtained results show that the distribution of the main chemical components of Aleppo pine unfired wood bark and sapwood is similar to the results of previous studies for different wood species. That means that the bark contains a significantly higher content of ash, accessory materials (extractives) and lignins, and a significantly lower content of polysaccharides cellulose and polyoses (hemicellulose) than sapwood. The bark results from previous studies show a significant difference in reduced ash, cellulose and lignin content, and in the increased accessory materials and wood polyoses (hemicellulose) content between the unfired and fired wood. Furthermore, the content of individual chemical components of fired bark at different forest fires heights of 0,2 and 4 m for each sample did not differ significantly. Contrary to fired bark, no significant differences have been observed in the chemical composition of sapwood between unfired and fired wood, not even resulting from different forest fires heights. It can be concluded that the forest fire did not have any effect on Aleppo pine sapwood, where the fired wood bark took over all the damage caused by high temperature during the forest fire. In addition, the fired sapwood still retains the chemical properties required for further application in biorefinery biobased products. Keywords: Aleppo pine (Pinus halepensis Mill.), sapwood group chemical composition, forest fires, fired wood
In order to describe seasonal flight activity of the cabbage maggot Delia radicum (L.) adults in relation to Julian days (JD), degree-day accumulations (DDA) and precipitation, flight dynamics were ...followed weekly with the use of yellow sticky traps (YST). Climatic data were collected and DDA were calculated using the lower developmental threshold of 4.3 °C. The efficacy of four insecticides applied either as standard foliar treatment or through dipping the seedlings before transplanting was determined. Seasonal flight activity during the cultivation season of a mid-early variety of white cabbage was correlated with DDA and JD and was characterized by having two peaks. The first peak occurred between 119 ± 7.5 JD and 125.5 ± 8 JD when DDA was 471.35 ± 74.97 °C. The second occurred between 172.8 ± 6.1 JD and 179.3 ± 6.7 JD when DDA was 1,217.28 ± 96.12 °C. The DDA, cumulative capture of flies and JD are suitable for predicting the timing of insecticide application. Spraying with insecticides should be applied when the cumulative capture of flies reaches 100 flies/YST and when DDA reaches 400 °C. If only one parameter reaches the threshold, additional visual surveys should be employed to establish the level of infestation. Insecticides were able to ensure only partial control. In the future, alternative control tactics which employ seed treatments and nonpesticide measures should be investigated in Croatia.
Šumski požari pojava su nekontrolirane vatre u šumama, nanose velike štete, što ovisi o starosti šume, vrstama drveća, odnosno vegetacije te o vrsti požara i njegovoj jačini, a nastaju rjeđe ...prirodnim uzrocima, a najčešće ljudskom djelatnošću. Kako na navedenim područjima nakon požara zaostanu znatne količine opožarenih stabala postavlja se pitanje u kojem stupnju su ona kemijski degradirana, odnosno da li ona i dalje posjeduju sva svojstva za daljnju primjenu u mehaničkoj ili kemijskoj preradi drva. Stoga, u ovom radu istraživan je utjecaj šumskih požara na grupni kemijski sastav kore drva crnog bora (Pinus nigra Arn.). Istraživanje je provedeno određivanjem grupnog kemijskog sastava (akcesorne tvari, mineralne tvari, celuloza, drvne polioze i lignin) kore opožarenog drva i neopožarenog drva crnog bora (radi usporedbe s korom opožarenog) uzorkovanjem kolutova na visinama stabla 0 m, 2 m i 4 m. Na temelju dobivenih rezultata kemijskih analiza kore opožarenog drva crnog bora utvrđen je utjecaj šumskih požara na promjenu samog kemijskog sastava usporedbom s kemijskim sastavom kore neopožarenog drva crnog bora. Dobiveni rezultati su pokazali značajnu različitost u smanjenom sadržaju pepela i drvnih polioza (hemiceluloze) te povećanom sadržaju celuloze i lignina između neopožarene i opožarene kore drva. Nadalje, pri istoj usporedbi kod sadržaja akcesornih tvari nismo uočili značajnu različitost.
Open-air fires or forest fires are becoming a key factor in reducing the forest surface areas and they are one of the major factors of devastation and degradation of forests and forest land and their ...ecosystems in the Mediterranean, mainly in coastal karst. They cause extreme material and economic damage, and they negatively affect biological and landscape diversity. After the forest fire, significant quantities of fired trees are left behind, representing a significant amount of lignocellulosic biomass available for conversion into a variety of biobased products. The question arises as to what degree they are chemically degraded, or whether they still have the properties required for further application in mechanical or chemical processing. The main aim of this paper was to study the group chemical composition as a biomass chemical property of the Aleppo pine (Pinus halepensis Mill.) sapwood before and after the impact of low ground fire and high fire of the treetops at tree height of 0, 2 and 4 m. Therefore, the impact of forest fires on the Allepo pine sapwood group chemical composition was studied in terms of quality for further application in production of biorefinery products. In addition, research results on group chemical composition of the same unfired and fired Aleppo pine wood bark from previous study were used for comparison with sapwood from this study. The obtained results show that the distribution of the main chemical components of Aleppo pine unfired wood bark and sapwood is similar to the results of previous studies for different wood species. That means that the bark contains a significantly higher content of ash, accessory materials (extractives) and lignins, and a significantly lower content of polysaccharides cellulose and polyoses (hemicellulose) than sapwood. The bark results from previous studies show a significant difference in reduced ash, cellulose and lignin content, and in the increased accessory materials and wood polyoses (hemicellulose) content between the unfired and fired wood. Furthermore, the content of individual chemical components of fired bark at different forest fires heights of 0, 2 and 4 m for each sample did not differ significantly. Contrary to fired bark, no significant differences have been observed in the chemical composition of sapwood between unfired and fired wood, not even resulting from different forest fires heights. It can be concluded that the forest fire did not have any effect on Aleppo pine sapwood, where the fired wood bark took over all the damage caused by high temperature during the forest fire. In addition, the fired sapwood still retains the chemical properties required for further application in biorefinery biobased products.
The horse chestnut (Aesculus hippocastanum L.) is an important feature in parks and avenues in many European cities. Over the last decade, the leaves of chestnut trees have been increasingly attacked ...by large larval populations of an insect of unknown origin – Cameraria ohridella (Deschka et Dimić). The attacked chestnuts cease to function as urban greenery and are often defoliated as early as late August. Therefore, it is of utmost importance to develop appropriate measures to control this pest. Foliar treatment of chestnuts with insecticides involves risks for humans, domestic animals and environmental contamination with insecticides, but these risks can be avoided by using endotherapeutic methods of insecticide application. This paper presents the first-in-city testing results of three different endotherapeutic methods of insecticide injection: controlled pressure injection, gravity (diffusion) injection and soil injection. Two different insecticides were applied in these trials – Confidor SL 200 with active ingredient imidaclopride and Vertimec 018 EC, a.i. abamectin. Trials were conducted in Zagreb, Croatia, during the period from 2003 to 2007. Each year, a minimum of 16 chestnut trees (15-25 m high) were included in four replications trials. Injection of insecticide by diffusion or gravitational methods usually takes too long (up to several days), which makes it unsuitable for public areas. Injecting the insecticide into the root zone in the soil with the use of the Shell Soil Fumigant Injector Model HI is also inappropriate, as it requires a very large dosage of insecticide to achieve successful control, which makes it too expensive and presents a greater risk of groundwater contamination. The most successful C. ohridella control was achieved with the application of Vertimec 018 EC and Confidor 200 SL using the controlled pressure application technique (Intus, Arbosan III Steel and injector constructed on Faculty of Agriculture, Zagreb). In practice, the application of imidaclopride was difficult with a pressure lower than 4.0 bars. The use of higher pressures is not recommended because of the risk of damaging the conductive tissue of the plant. Application with a pressure lower than 4.0 bars is easy to use with abamectin.
In order to describe seasonal flight activity of the cabbage maggot Delia radicum (L.) adults in relation to Julian days (JD), degree-day accumulations (DDA) and precipitation, flight dynamics were ...followed weekly with the use of yellow sticky traps (YST). Climatic data were collected and DDA were calculated using the lower developmental threshold of 4.3 °C. The efficacy of four insecticides applied either as standard foliar treatment or through dipping the seedlings before transplanting was determined. Seasonal flight activity during the cultivation season of a mid-early variety of white cabbage was correlated with DDA and JD and was characterized by having two peaks. The first peak occurred between 119 ± 7.5 JD and 125.5 ± 8 JD when DDA was 471.35 ± 74.97 °C. The second occurred between 172.8 ± 6.1 JD and 179.3 ± 6.7 JD when DDA was 1,217.28 ± 96.12 °C. The DDA, cumulative capture of flies and JD are suitable for predicting the timing of insecticide application. Spraying with insecticides should be applied when the cumulative capture of flies reaches 100 flies/YST and when DDA reaches 400 °C. If only one parameter reaches the threshold, additional visual surveys should be employed to establish the level of infestation. Insecticides were able to ensure only partial control. In the future, alternative control tactics which employ seed treatments and nonpesticide measures should be investigated in Croatia.
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