UVJETI UZGOJA I SORTIMENT TIKVENJAČA

U radu su navedeni uvjeti uzgoja najvažnijih povrtnih vrsta iz porodice tikvenjača (krastavac, dinja, lubenica, tikvica) koji određuju moguće rokove uzgoja na otvorenom i u zaštićenim prostorima. Dat je pregled morfoloških svojstava najvažnijih varijeteta, odnosno tipova kultivara navedenih vrsta za različite namjene i načine korištenja

The Quality of Fresh Tomato Fruit Produced by Hydroponic

The quality of fresh tomatoes (Lycopersicon esculentum Mill.) planted in rockwool in hydroponic system is defined by their internal parameters: contents of dry matter and soluble dry matter (°Bx), total acidity (% citric acid), pH, % NaCl and L-ascorbic acid. Research was carried out during 2003 and included 21 cultivars. Tomato plants were planted into rockwool slabs 100 cm x 15 cm x 7.5 cm. Three plants were planted 33 cm apart in 11.25 L of substrate. The trial was laid out according to the randomized complete block design with four replications, and sampling was carried out during three harvests in: June, July and August. The dry matter content was 4.29% (cultivar ΄Syta΄) to 6.21% (cultivar ΄Delfine΄), and content of soluble dry matter was 3.0% (cultivar ΄Brooklyn΄) to 4.5% (΄Lustro΄ and ΄72-503΄). Total acidity amounted from 0.19% (cultivar ΄Syta΄) to 0.45% (cultivar ΄Lustro΄), and pH values ranged from 4.20 (cultivar ΄20377΄) to 4.68 (cultivar ΄Syta΄). Salt content ranged from 0.08% (΄Campeon΄ and ΄F 18402΄) to 0.13% (΄Brooklyn΄ and ΄E 27.31299΄), and L-ascorbic acid content ranged from 260.40 (cultivar ΄Antinea΄) to 458.30 mg/dry matter (cultivar ΄F 18402΄). By studying the basic chemical composition of selected cultivars, significant differences in their soluble dry matter and pH were revealed but only at the first sampling

Moisture regime in Hortisol and lettuce yield under different mulching conditions

Cilj istraživanja bio je utvrditi utjecaj mrtvih organskih malčeva (neprerađena ovčja vuna – SW i „filcana“ ekološka vuna – EW), crnog polietilenskog filma (PE) i nemalčiranog tla (WM) na režim vlažnosti hortisola i prinos salate kultivara \u27Melina\u27. Istraživanje je provedeno na pokušalištu Agronomskog fakulteta u Zagrebu u razdoblju od travnja do lipnja 2017. godine, a pokus je postavljen prema slučajnom bloknom rasporedu u tri ponavljanja. Uzorkovanje tla obavljeno je dekadno sa dubina 0-10 cm i 10-20 cm, u 3 ponavljanja, a sadržaj vlage u tlu određen je gravimetrijskom metodom. Na sadržaj trenutačne vlage u tlu statistički su značajno utjecali: dani nakon presađivanja salate na otvoreno (DAT) i malč (M). Statistički najniže vrijednosti vlage u tlu utvrđene su kod 46 DAT, a značajno više kod 5 DAT. S obzirom na vrstu malča,u oba sloja tla trenutačna vlažnost se kretala slijedećim redom: PE > SW > EW > WM. Na promjer rozete salate nije značajno utjecala vrsta malča. Rozeta salate uzgajane na SW (20,7 cm) bila je značajno viša u odnosu na PE (18,4 cm), EW (18,0 cm) i WM (17,8 cm).Najviši tržni prinos salate ostvaren je pod vunenim malčevima (6,58 kg/m2 na EW, odnosno 6,56 kg/m2na SW), a najniži pod PE (4,60 kg/m2). Vuneni malčevi pokazali su se dobrom alternativom dosadašnjoj primjeni PE malčeva.The aim of the study was to determine the impact of dead organic mulches (unprocessed sheep wool - SW and ecological wool - EW), black polyethylene film (PE) and unmulched soil (WM) on the moisture regime of Hortisol and the yield of lettuce cv.´Melina´.The research was carried out at an trial field at the Faculty of Agriculture in Zagreb from April to June 2017. The experiment was set out according to a randomized block design with three replications. Soil samples were taken decadally from depths of 0-10 cm and 10-20 cm, in 3 replications, and the soil moisture content was determined by gravimetric method. The current moisture content in the soil was significantly influenced by: days after transplatation lettuce to open field (DAT) and mulch (M). The significantly low values of soil moisture were determined at 46 DAT, and high at 5 DAT. Considering the mulch, the soil moisture in both layers as follows: PE> SW> EW> WM. Diameter of the lettuce rosette was not significantly affected by the mulch type. Lettuce rosette, grown on SW (20.7 cm) was significantly higher compared to PE (18.4 cm), EW (18.0 cm) and WM (17.8 cm). The highest marketable yield of lettuce was achieved when wool mulch was applied (6.58 kg/m2 on EW, ie 6.56 kg/m2 on SW), and the lowest under PE (4.60 kg/m2). Woolen mulches have proved to be a good alternative to the previous application of PE mulches

MAGNESIUM CONTENT IN CAULIFLOWER AT SALES PLACES IN ZAGREB

Cauliflower (Brassica oleracea var. botrytis) is a biennial crop belonging to the mustard family. It is grown for a head consisting of a thick, short, hypertrophied flower stem with undifferentiated flowers and flower embryos. The minerals that are most abundant in cauliflower are sodium, potassium, magnesium, calcium, phosphorus, iron, and sulfur. Magnesium is an essential element for almost all living beings, it is involved in many processes such as the synthesis of organic substances, it is responsible for the activation of a large number of enzymes and has a beneficial effect on the metabolism of carbohydrates, proteins and fats. The aim of this article was to determine the content of magnesium in cauliflower available in the city of Zagreb and to determine how much magnesium can be settled by consuming that cauliflower. The sampling was carried out at 9 sales places in the city of Zagreb, of which 3 were stores with organic products, 3 markets and 3 retail chains. Magnesium was determined by atomic absorption spectrometry after digestion with concentrated HNO3 and HClO4 in a microwave oven. The magnesium content of cauliflower ranged from 0.17 to 0.22% Mg in dry matter, 21.24 to 38.87 mg Mg/100 g in the fresh matter, and it was found that consuming 100 g of cauliflower can satisfy 5.98-10.75% of our daily need for magnesium

The effect of plant density on morphological traits and yield of broccoli

Na tržištu je prisutan velik broj hibridnih sorti brokule različitih morfoloških svojstava cvata i duljine vegetacije. Ovisno o cilju uzgoja brokule (vršni ili postrani cvatovi) te namjeni (za potrošnju u svježem stanju ili za preradu) proizvođači se odlučuju za različite sorte i razmake sadnje. Stoga je postavljeno istraživanje s ciljem utvrđivanja utjecaja sklopa, odnosno, različitih razmaka sadnje na morfološka svojstva i prinos hibridnih sorti brokule u proljetno-ljetnom roku uzgoja. Testirane su dvije gustoće sklopa (3,3 i 2,8 b/m2) ostvarene razmacima sadnje 60 x 50 cm i 70 x 50 cm. Tijekom višekratnih berbi brokule utvrđena je masa, promjer i prinos vršnog cvata te dužina i promjer cvatne stapke. Sorta Captain ostvarila je najveću masu, promjer i prinos vršnog cvata (335 g, 12,5 cm i 10,3 t/ha) te imala najdužu cvatnu stapku (7,6 cm). Najveći prinos (10,8 t/ha) ostvarila je sorta Captain pri razmaku sadnje 60 x 50 cm zbog većeg broja biljaka po m2, dok je pri većem vegetacijskom prostoru ostvarenom razmakom sadnje 70 x 50 cm ostvarila veće vrijednosti mase i morfometrijskih svojstava.There is a large number of broccoli hybrid cultivars with different morphological traits and the length of the vegetation. Depending on the cultivation purpose of broccoli (top or lateral inflorescences) and use (fresh-market consumption of for processing), producers use different cultivars and plant densities. The aim of this research was to determine the effect of plant density, i.e. different spacing between rows, on the morphological characteristics and yield of broccoli hybrid cultivars in the spring-summer growing period. Two plant densities: 60 x 50 cm (3.3 plants/m2) and 70 x 50 cm (2.8 b/m2) were tested. During the harvest period, basic morphometric values were determined: mass, diameter and yield of top inflorescence, length and diameter of stem. ‘Captain’ had the highest top inflorescence mass, diameter and yield (335 g, 12.5 cm and 10.3 t/ha) and the longest stem (7.6 cm). It also achieved the highest yield (10.8 t/ha) at the higher density (60 x 50 cm) due to the large number of plants per m2, while at 70 x 50 cm higher values of weight and morphometric traits were recorded

The effect of plant density on morphological traits and yield of broccoli

Na tržištu je prisutan velik broj hibridnih sorti brokule različitih morfoloških svojstava cvata i duljine vegetacije. Ovisno o cilju uzgoja brokule (vršni ili postrani cvatovi) te namjeni (za potrošnju u svježem stanju ili za preradu) proizvođači se odlučuju za različite sorte i razmake sadnje. Stoga je postavljeno istraživanje s ciljem utvrđivanja utjecaja sklopa, odnosno, različitih razmaka sadnje na morfološka svojstva i prinos hibridnih sorti brokule u proljetno-ljetnom roku uzgoja. Testirane su dvije gustoće sklopa (3,3 i 2,8 b/m2) ostvarene razmacima sadnje 60 x 50 cm i 70 x 50 cm. Tijekom višekratnih berbi brokule utvrđena je masa, promjer i prinos vršnog cvata te dužina i promjer cvatne stapke. Sorta Captain ostvarila je najveću masu, promjer i prinos vršnog cvata (335 g, 12,5 cm i 10,3 t/ha) te imala najdužu cvatnu stapku (7,6 cm). Najveći prinos (10,8 t/ha) ostvarila je sorta Captain pri razmaku sadnje 60 x 50 cm zbog većeg broja biljaka po m2, dok je pri većem vegetacijskom prostoru ostvarenom razmakom sadnje 70 x 50 cm ostvarila veće vrijednosti mase i morfometrijskih svojstava.There is a large number of broccoli hybrid cultivars with different morphological traits and the length of the vegetation. Depending on the cultivation purpose of broccoli (top or lateral inflorescences) and use (fresh-market consumption of for processing), producers use different cultivars and plant densities. The aim of this research was to determine the effect of plant density, i.e. different spacing between rows, on the morphological characteristics and yield of broccoli hybrid cultivars in the spring-summer growing period. Two plant densities: 60 x 50 cm (3.3 plants/m2) and 70 x 50 cm (2.8 b/m2) were tested. During the harvest period, basic morphometric values were determined: mass, diameter and yield of top inflorescence, length and diameter of stem. ‘Captain’ had the highest top inflorescence mass, diameter and yield (335 g, 12.5 cm and 10.3 t/ha) and the longest stem (7.6 cm). It also achieved the highest yield (10.8 t/ha) at the higher density (60 x 50 cm) due to the large number of plants per m2, while at 70 x 50 cm higher values of weight and morphometric traits were recorded

Agronomic traits of tomato at different ammonium nitrate concentrations in the nutrient solution

Cilj istraživanja bio je utvrditi agronomska svojstva dva kultivara rajčice u hidroponskom uzgoju na kamenoj vuni, pri standardnoj i 50 % povećanoj koncentraciji amonijevog nitrata u hranjivoj otopini. Tijekom plodonošenja brani su plodovi s 8 grozdova prikraćenih na 5 plodova. Utvrđeni su masa i prinos tržnih plodova po grozdu i ukupno, broj tržnih i netržnih plodova po m2 te udio netržnih plodova sa simptomima vršne truleži. Po m2 ubrano je od 99,2 do 112,0 tržnih plodova, a udio netržnih plodova je iznosio od 5,42 do 8,38 %. U interakciji sa standardnom otopinom oba kultivara su na svim grozdovima razvila krupnije plodove. Tijekom plodonošenja razvili su plodove podjednake krupnoće (od 205 do 207 g). Najkrupnije plodove, mase 220 g razvio je kultivar Buran uz primjenu standardne hranjive otopine. Kultivar Buran je ostvario 7,24 % viši ukupni tržni prinos od kultivara Belle (21,40 kg/m2) dok je primjenom standardne hranjive otopine ostvaren 13,79 % viši prinos u odnosu na otopinu s povećanom koncentracijom NH4NO3 (20,74 kg/m2). Najviši ukupni tržni prinos ostvario je kultivar Buran uz primjenu standardne hranjive otopine (24,55 kg/m2), a najniži kultivar Belle uz primjenu hranjive otopine s povećanom koncentracijom amonijevog nitrata (20,13 kg/m2). Zbog razvijenih krupnijih plodova i višeg ostvarenog prinosa te manjeg udjela netržnih plodova prilikom primjene standardne otopine za krupnoplodne kultivare se ne preporučuje povećanje koncentracije amonijevog nitrata u hranjivoj otopini.The aim of this research was to determine the agronomic traits of two tomato cultivars grown in soilless culture on rockwool, fertigated with the standard and 50 % increased ammonium nitrate concentration in the nutrient solution. During the harvest period, fruits from 8 clusters shortened to 5 fruits were harvested. Fruit weight and marketable yield per cluster and in total, the number of marketable and unmarketable fruits per m2 and share of unmarketable fruits with blossom-end rot symptoms were determined. Between 99.2 and 112.0 marketable fruits was harvested per m2, while the share of unmarketable fruits varied from 5.42 to 8.38 %. Both cultivars developed larger fruits in all clusters when they were fertigated with the standard nutrient solution. During the harvest period they developed fruits which weighed between 205 to 207 g, respectively. Cv. ‘Buran’ fertigated with the standard nutrient solution has developed the highest fruit weight (220 g). The same cultivar has achieved a 7.24 % higher marketable yield than cultivar Belle (21.40 kg/m2). Fertigation with the standard nutrient solution resulted in 13.79% higher yield compared to the solution with higher NH4NO3 concentration (20.74 kg/m2). The highest total marketable yield (24.55 kg/m2) was achieved by cv ‘Buran’ fertigated with the standard nutrient solution, while the lowest (20.13 kg/m2) was achieved by cv. ‘Belle’ fertigated with nutrient solution that contained higher concentration of ammonium nitrate. Because of the higher fruit weight and marketable yield, and also the lower unmarketable fruits share was achieved with the standard nutrient solution, increasing the ammonium nitrate concentration for beefsteak cultivars is not recommended

Agronomic traits of tomato at different ammonium nitrate concentrations in the nutrient solution

Cilj istraživanja bio je utvrditi agronomska svojstva dva kultivara rajčice u hidroponskom uzgoju na kamenoj vuni, pri standardnoj i 50 % povećanoj koncentraciji amonijevog nitrata u hranjivoj otopini. Tijekom plodonošenja brani su plodovi s 8 grozdova prikraćenih na 5 plodova. Utvrđeni su masa i prinos tržnih plodova po grozdu i ukupno, broj tržnih i netržnih plodova po m2 te udio netržnih plodova sa simptomima vršne truleži. Po m2 ubrano je od 99,2 do 112,0 tržnih plodova, a udio netržnih plodova je iznosio od 5,42 do 8,38 %. U interakciji sa standardnom otopinom oba kultivara su na svim grozdovima razvila krupnije plodove. Tijekom plodonošenja razvili su plodove podjednake krupnoće (od 205 do 207 g). Najkrupnije plodove, mase 220 g razvio je kultivar Buran uz primjenu standardne hranjive otopine. Kultivar Buran je ostvario 7,24 % viši ukupni tržni prinos od kultivara Belle (21,40 kg/m2) dok je primjenom standardne hranjive otopine ostvaren 13,79 % viši prinos u odnosu na otopinu s povećanom koncentracijom NH4NO3 (20,74 kg/m2). Najviši ukupni tržni prinos ostvario je kultivar Buran uz primjenu standardne hranjive otopine (24,55 kg/m2), a najniži kultivar Belle uz primjenu hranjive otopine s povećanom koncentracijom amonijevog nitrata (20,13 kg/m2). Zbog razvijenih krupnijih plodova i višeg ostvarenog prinosa te manjeg udjela netržnih plodova prilikom primjene standardne otopine za krupnoplodne kultivare se ne preporučuje povećanje koncentracije amonijevog nitrata u hranjivoj otopini.The aim of this research was to determine the agronomic traits of two tomato cultivars grown in soilless culture on rockwool, fertigated with the standard and 50 % increased ammonium nitrate concentration in the nutrient solution. During the harvest period, fruits from 8 clusters shortened to 5 fruits were harvested. Fruit weight and marketable yield per cluster and in total, the number of marketable and unmarketable fruits per m2 and share of unmarketable fruits with blossom-end rot symptoms were determined. Between 99.2 and 112.0 marketable fruits was harvested per m2, while the share of unmarketable fruits varied from 5.42 to 8.38 %. Both cultivars developed larger fruits in all clusters when they were fertigated with the standard nutrient solution. During the harvest period they developed fruits which weighed between 205 to 207 g, respectively. Cv. ‘Buran’ fertigated with the standard nutrient solution has developed the highest fruit weight (220 g). The same cultivar has achieved a 7.24 % higher marketable yield than cultivar Belle (21.40 kg/m2). Fertigation with the standard nutrient solution resulted in 13.79% higher yield compared to the solution with higher NH4NO3 concentration (20.74 kg/m2). The highest total marketable yield (24.55 kg/m2) was achieved by cv ‘Buran’ fertigated with the standard nutrient solution, while the lowest (20.13 kg/m2) was achieved by cv. ‘Belle’ fertigated with nutrient solution that contained higher concentration of ammonium nitrate. Because of the higher fruit weight and marketable yield, and also the lower unmarketable fruits share was achieved with the standard nutrient solution, increasing the ammonium nitrate concentration for beefsteak cultivars is not recommended

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