Cultivation of broccoli

Svjetska proizvodnja brokule (Brassica oleracea L. var. italica) je u stalnom porastu zbog povećanog zanimanja za ovu namirnicu visoke hranidbene vrijednosti ali i dokazanog kemoprotektivnog djelovanja. U Hrvatskoj raznolikost klimatskih prilika pruža veliki potencijal za uzgoj brokule, te se odgovarajućim izborom kultivara, rokova uzgoja i proizvodnog područja može osigurati kontinuiranost opskrbe tržišta i prerađivačke industrije tijekom cijele godine.The world production of broccoli (Brassica oleracea L. var. italica) is constantly increasing as a result of increased interest for this highly nutritious food and evidencebased chemoprotective effect as well. In Croatia, a continuous supply of fresh broccoli to the processing industry and the market can be realized by selecting a suitable hybrid broccoli cultivars, optimal growing periods and production area

TRŽIŠTE NAFTNIH DERIVATA ŠIRE REGIJE JUGOISTOČNE EUROPE

U posljednjih nekoliko godina pod utjecajem globalne ekonomske krize došlo je do značajnog pada potrošnje naftnih derivata u zemljama regije. Kako bi se što preciznije utvrdio utjecaj krize na potrošnju analizom je obuhvaćena šira regija koja uključuje Hrvatsku, Srbiju, Bosnu i Hercegovinu, Makedoniju, Sloveniju, Crnu Goru, Kosovo, Češku, Slovačku, Mađarsku, Rumunjsku, Bugarsku, Grčku, Albaniju, Italiju i Austriju. Pad potrošnje prvenstveno je posljedica globalne ekonomske krize, ali i smanjenja ukupnog broja stanovnika u regiji, povećanja energijske efikasnosti te supstitucije fosilnih goriva drugim oblicima energije. Pad potrošnje naftnih derivata za 15 % u razdoblju od 2007. do 2012. imao je izravan utjecaj na razinu prerade u rafinerijama regije. Nekoliko rafinerija već je zatvoreno ili su prenamijenjene u skladišne centre dok su druge obustavile ili smanjile proizvodnju na pojedinim proizvodnim postrojenjima. Kako se u skorijoj budućnosti ne prognozira značajan porast potrošnje mogu se očekivati daljnja zatvaranja rafinerijskih kapaciteta

Glucosinolates concentration and yield of broccoli cultivars in different growing periods

Potrošnja brokule u Hrvatskoj porasla je tijekom posljednjih desetak godina zbog njezine izuzetne nutritivne vrijednosti koja ovisi o genetskim, abiotskim i agrotehničkim čimbenicima. Zbog genotipa, sorte brokule se razlikuju u koncentraciji bioaktivnih spojeva, odnosno, učinku na ljudsko zdravlje. Promjenjiv sastav i koncentracija fitotvari glavni su problem pri proizvodnji povrća kao funkcionalne hrane, od koje se očekuje ujednačena razina zdravstvene vrijednosti. Budući da je na tržištu prisutan raznolik sortiment, postavljeno je istraživanje s ciljem odabira perspektivnih sorata brokule, za uzgoj u uvjetima sjeverozapadne Hrvatske, odgovarajućeg prinosa i koncentracije pojedinačnih te ukupnih glukozinolata u različitim rokovima uzgoja. Najveći prinos tržnog vršnog cvata ostvarila je sorta Parthenon (13,3 t/ha) u proljetno-ljetnom roku, odnosno sorta Montop (15,0 t/ha) u ljetno-jesenskom roku uzgoja. Testirane sorte brokule statistički su se značajno razlikovale u koncentraciji ukupnih glukozinolata. Tijekom proljetno-ljetnog roka uzgoja u vršnom cvatu sorata brokule utvrđene su značajno veće vrijednosti ukupnih glukozinolata (12 do 22,5 μmol/g suhe tvari), nego u ljetno-jesenskom uzgojnom roku (5,4 do 15,5 μmol/g suhe tvari).In recent decades, broccoli consumption in Croatia increased due to its exceptional nutritive value, which depends on genetic, abiotic factors and agronomic factors. Because of the genotype, there are significant variation in the concentration of bioactive compounds among broccoli cultivars which affects on the human health. Variations in concentration of phytochemicals is the major problem in the production of vegetables as functional food, while uniform level of health is expected.As numerous broccoli cultivars are available at the market, research with the aim to select promising hybrid broccoli cultivars for growing in agroecological conditions of northwestern Croatia, with high values of yield and concentration of individual and total glucosinolates in different growing periods. The highest values of top inflorescence yield were achieved by ‘Parthenon’ (13.3 t/ha) in spring-summer growing period and ‘Montop’ (15.0 t/ha) in summer-autumn growing period. There were significant differences among broccoli cultivars in total glucosinolates concentration. The values of total glucosinolates in broccoli top inflorescence were significantly higher during spring-summer growing period (12 to 22.5 μmol/g dry weight) than in summer-autumn growing period (5.4 to 15.5 μmol/g dry weight)

Root rot in hydroponic cultivation with reference to Thielaviopsis basicola and Pythium sp.

U radu su navedeni uzročnici bolesti koji su do sada dokazani u hidroponskom uzgoju (Botrytis cinerea, Passalora fulva, Sclerotinia sclerotiorum, Erysiphe cichoracearum, Pseudomonas corugata, Phytophtora parasitica, Fusarium oxysporum, Pythium spp.) na kamenoj vuni u nas. Uvođenjem novih tehnika uzgoja kao npr. uzgoju na plutajućim kontejnerima i akvaponici pojavile su se do sada kod nas nezabilježene bolesti. Tako su 2011. na salati, a 2012. godine na matovilcu došlo do truleži korijena, u uzgoju na plutajućim kontejnerima. U 2016. godini na salati u sistemu akvaponike također su primijećene promjene na biljkama salate. Opisani su simptomi i determinirani uzročnici bolesti. Na korijenu matovilca konstatirana je gljiva Thielaviopsis basicola, a na salati, bez obzira na način uzgoja utvrđena je Pythium vrsta. Prodiskutirane su prednosti i nedostatci proizvodnje povrća u hidroponskom uzgoju i predložene mjere zaštite. Ovo su prvi nalazi Thielaviopsis basicola na matovilcu i Pythium vrste na salati u hidroponskom uzgoju u Hrvatskoj.The paper lists causal agents of diseases that have so far been established in hydroponic cultivation (Botrytis cinerea, Passalora fulva, Sclerotinia sclerotiorum, Erysiphe cichoracearum, Pseudomonas corugata, Phytophthora parasitica, Fusarium oxysporum, Pythium spp.) on mineral wool in Croatia. With the introduction of some new techniques of cultivation, such as cultivation on the floating containers and aquaponics, some new diseases previously undetected in Croatia have emerged. Thus, in the cultivation on the floating containers, in 2011 on lettuce (Lactuca sativa) and in 2012 on lamb’s lettuce (Valerianella olitoria), root rot were observed. Also the same changes on roots were observed on lettuce in aquaponics in 2016. In this paper symptoms of these diseases were described and their causal agents determined. Fungus Thielaviopsis basicola was found on roots of lamb’s lettuce while a Pythium species, regardless of the method of cultivation, was found on lettuce. The advantages and disadvantages of vegetable production in hydroponics were discussed and protection measures were proposed. These are the first reports of Thielaviopsis basicola on lamb’s lettuce and Pythium on lettuce in hydroponic cultivation in Croatia

Hydroponic Production Systems in Greenhouses

Hydroponic production means the growing of vegetables, herbs and ornamental plants and fruits in a nutrient solution (a solution of water and macro- and micronutrients) with or without the use of a substrate that gives the mechanical support to plant. The most important advantages of hydroponics are as follows: continuous cultivation of one crop, better control and supply of plants with water and plant nutrients, reduced occurrence of plant pests and minimized environmental impact and increased water use efficiency. The main hydroponic cultivation technique of fruit vegetables is cultivation on substrates, often called soilless system. Growing substrate (organic, inorganic or synthetic) provides an aseptic environment, good oxygenation and an adequate nutrient solution flow, so the most important substrate properties are biological and chemical inert, porosity and capillarity. Its choice depends on climatic conditions, the type of equipment in the greenhouse and the plant requirements. Hydroponics is also suitable for growing crops with a shorter growing period such as leafy vegetables and herbs. Plants are grown by different growing techniques in a nutrient solution without a substrate (nutrient film technique, floating hydroponics, ebb and flow and aeroponics). These are closed hydroponic systems, which means that drainage nutrient solution is collected, sterilized and reused

The effect of abiotic factors, sowing density and multiple harvest to arugula yield in floating hydroponic

U istraživanju je vrednovan utjecaj gustoće sjetve (6 i 9 g m-2) i višekratne berbe (dva i tri navrata) na prinos rige sorta ‘Coltivata’ u plutajućem hidroponu. U cjelogodišnjem uzgoju u zaštićenom prostoru također je promatran utjecaj abiotskih čimbenika tijekom tri razdoblja uzgoja (ljeto, jesen-zima i proljeće). Tijekom 339 dana istraživanja provedena su 24 pokusa, postavljena po metodi slučajnog bloknog rasporeda u četiri ponavljanja. Promatrani abiotski čimbenici (temperatura, količina otopljenog kisika, pH- i EC-vrijednost) hranjive otopine bili su u rasponu: 12,4 do 26,1°C, 3,6 do 8,1 mg L-1, 5,4 do 6,6 i 2,7 do 3,3 dS m-1. Najmanja i najveća temperatura zraka bile su u rasponu 5,3 do 18,0°C i 16,4 do 45,1°C, a relativna vlaga zraka 48,1 do 78,9%. Najkraći proizvodni ciklus (36 dana od sjetve do druge berbe) bio je u ljetnom roku uzgoja s prosječnim vrijednostima abiotskih čimbenika: temperatura zraka i hranjive otopine 28,1 i 25,3°C, relativna vlaga zraka 53,6% i količina otopljenog kisika 5,0 mg L-1. Najduži proizvodni ciklus (77 dana) bio je u jesensko-zimskom roku uzgoja s najmanjom temperaturom zraka i hranjive otopine (14,2 i 15,2°C), najvećom relativnom vlagom zraka (73,5%) i količinom otopljenog kisika (6,9 mg L-1). Veća gustoća sjetve u prvoj, drugoj i trećoj berbi rezultirala je 17, 30 i 50% većim prinosom u odnosu na manju gustoću sjetve. Bez obzira na gustoću sjetve najveći udio u ukupnom prinosu (53%) ostvaren je u prvoj berbi, manji (29%) u drugoj i najmanji (18%) u trećoj.The research valued the effect of sowing density (6 i 9 g m-2) and multiple harvest (two and three occasions) to arugula yield of “Coltivata” variety in a floating hydroponic. The effect of abiotic factors was also monitored in a year-long cultivation in a protected space during three periods of cultivation (summer, autumn – winter and spring). During 339 days of research there were conducted 24 experiments, set by the method of of randmomized block design in four replicates. The observed abiotic factors (temperature, content of dissolved oxygen, pH- and EC- value) of nutrient solution were in the range: 12.4 to 26.1 °C, 3.6 to 8.1 mg L-1, 5.4 to 6.6 and 2.7 to 3.3 dS m-1. The lowest and highest temperature of the air were in the range from 5.3 to 18.0 °C and 16.4 to 45.1 °C, and relative air humidity 48.1 to 78.9 %. The shortest production cycle (36 days from sowing to the second harvest) was in the summer period of cultivation with average values of abiotic factors: air temperature and nutrient solution 28.1 and 25.3°C, relative air humidity 53.6% and content of dissolved oxygen 5.0 mg L-1. The longest production cycle (77 days) was in the autumn – winter period of cultivation with the lowest air temperature and nutrient solution (14.2 and 15.2°C), the highest relative air humidity (73.5%) and content of dissolved oxygen (6.9 mg L-1). Higher sowing density in the 1st, 2nd and 3rd harvest resulted in 17, 30 and 50% higher yield in comparison to lower sowing density. Regardless of sowing density, the highest share in total yield (53%) was achieved in the 1st harvest, lower (29%) in the 2nd and and the lowest (18%9 in the 3rd one

Kako povećati nutritivnu kakvoću koprive kontroliranom ishranom

Research background. As food production faces major challenges, modern agricultural practices are increasingly focused on conserving resources, reducing negative environmental impacts and sustainably producing food with a high content of health-promoting phytochemicals. During production, many factors can affect the quality and chemical composition of a final food product. Proper selection of cultivating conditions, especially a balanced nutrition, can significantly increase nutritional value and result in foods with strong biological and functional properties. Stinging nettle is a rich source of minerals, vitamins, pigments, phenols and other bioactive compounds and can be consumed as a green leafy vegetable with beneficial effects on human health. Therefore, the aim of this study is to determine the nutritional quality and antioxidant capacity of stinging nettle leaves under the influence of different nutrient solution (NS) treatments and three harvest cycles. Experimental approach. The experiment was conducted in a floating hydroponic system in which treatments with different nutrient solutions were applied and three harvest cycles were carried out. After each harvest, the following treatments were applied: treatment 1 – depletion of nutrient solution by adding water, treatment 2 – supplementation of nutrient solution by adding initial nutrient solution and treatment 3 – correction of nutrient solution by adding nutrients. Among the bioactive compounds, minerals, ascorbic acid, phenols and photosynthetic pigments content, as well as antioxidant capacity were analysed spectrophotometrically, while individual phenols were determined by liquid chromatography. Results and conclusions. Different nutrition solution treatments and the number of harvest cycles had a significant effect on the content of the analysed bioactive compounds. The highest mass fraction (on fresh mass basis) of total phenols expressed as gallic acid equivalents (377.04 mg/100 g), total flavonoids expressed as catechol equivalents (279.54 mg/100 g), ascorbic acid (112.37 mg/100 g) and pigments (total chlorophylls 1.84, and total carotenoids 0.36 mg/g) as well as the highest antioxidant capacity expressed as Trolox equivalents (35.47 µmol/g) were recorded in the samples supplemented with nutrient solution (treatment NS2) and analysed after the third harvest. Novelty and scientific contribution. This is the first time that stinging nettle leaves have been produced in a floating hydroponic system by controlled plant nutrition. We have set this type of nutritional manipulation with multiple harvest cycles as an innovative technique for the production of novel food with improved nutritional value that can be consumed as green leafy vegetables.Pozadina istraživanja. Budući da se proizvodnja hrane suočava s velikim izazovima, suvremene poljoprivredne prakse sve su više usmjerene na očuvanje resursa, smanjenje negativnog učinka na okoliš i održivu proizvodnju hrane s velikim udjelom fitokemikalija koje pozitivno utječu na ljudsko zdravlje. Tijekom uzgoja, brojni čimbenici mogu utjecati na kakvoću i kemijski sastav konačnog proizvoda. Pravilnim odabirom uvjeta uzgoja, posebice uravnoteženom ishranom (gnojidbom), može se znatno povećati nutritivna kakvoća sirovine te pozitivno utjecati na njezina biološka i funkcionalna svojstva. Kopriva je bogat izvor mineralnih tvari, vitamina, pigmenata, fenola i drugih bioaktivnih spojeva, a može se konzumirati kao zeleno lisnato povrće blagotvornog učinka na zdravlje ljudi. Stoga je svrha ovog istraživanja bila odrediti nutritivnu kakvoću i antioksidacijski kapacitet lista koprive tretirane različitim hranjivim otopinama tijekom tri ciklusa berbe. Eksperimentalni pristup. Pokus je proveden u plutajućem hidroponskom sustavu u kojem su biljke tretirane različitim hranjivim otopinama tijekom tri ciklusa berbe. Korišteni su sljedeći postupci: tretman 1 – iscrpljivanje hranjive otopine vodom, tretman 2 – prihrana standardnom hranjivom otopinom i tretman 3 – korekcija sastava hranjive otopine dodatkom nutrijenata. Od bioaktivnih spojeva ispitani su maseni udjeli mineralnih tvari, askorbinske kiseline, ukupnih fenola i fotosintetskih pigmenata, te je utvrđen antioksidacijski kapacitet pomoću spektrofotometrije, dok su udjeli pojedinih fenola određeni tekućinskom kromatografijom. Rezultati i zaključci. Različiti tretmani hranjivim otopinama i broj ciklusa berbe bitno su utjecali na udjele ispitanih bioaktivnih spojeva u listu koprive. Najveći udjel (u svježoj masi lista) ukupnih fenola izražen kao ekvivalent galne kiseline (377,04 mg/100 g), ukupnih flavonoida izražen kao ekvivalent katehola (279,54 mg/100 g), askorbinske kiseline (112,37 mg/100 g) i pigmenata (ukupni klorofili 1,84, ukupni karotenoidi 0,36 mg/g), te najveći antioksidacijski kapacitet izražen kao ekvivalent Troloxa (35,47 µmol/g) zabilježeni su u uzorcima prihranjenim standardnom hranjivom otopinom, ispitanim nakon treće berbe. Novina i znanstveni doprinos. Kopriva je prvi put uzgojena u plutajućem hidroponskom sustavu s kontroliranom ishranom biljaka. Ovaj način uzgoja uz višestruke cikluse berbe je postavljen kao inovativna tehnika proizvodnje nove hrane, poboljšane nutritivne vrijednosti, koja se može konzumirati kao zeleno lisnato povrće