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Landscape design of Copacabana beach in Osijek
No full textPlaža Copacabana u Osijeku, smještena na sjevernoj obali rijeke Drave, vrijedan je javni otvoreni prostor rekreacijskog karaktera s izraženim društvenim, krajobraznim i ekološkim potencijalima, ali i brojnim funkcionalnim ograničenjima. U radu su analizirani ključni prostorni problemi koji umanjuju njegovu uporabnu i oblikovnu vrijednost. Na temelju prostorne inventarizacije, analize i višekriterijske analize izrađeno je idejno krajobrazno rješenje koje uključuje unaprjeđenje prostorne strukture i uvođenje novih sadržaja te unaprjeđenja prostorne funkcionalnosti i ambijentalne vrijednosti. Prijedlog se temelji na načelima održivog oblikovanja i multifunkcionalnosti, s ciljem afirmacije identiteta prostora i njegove integracije u širi sustav zelene infrastrukture grada.The Copacabana Beach in Osijek, located on the northern bank of the Drava River, is a valuable public open space with a recreational character and pronounced social, landscape, and ecological potential, but also numerous functional limitations. This paper analyzes the key spatial issues that reduce its usability and design value. Based on spatial inventory, analysis, and multi-criteria evaluation, a conceptual landscape design proposal has been developed. It includes the improvement of spatial structure, the introduction of new amenities, and the enhancement of spatial functionality and ambient value. The proposal is grounded in the principles of sustainable design and multifunctionality, with the aim of affirming the identity of the space and integrating it into the broader green infrastructure system of the city
Expenses of employees in agriculture
No full textU ovom radu naglasak se stavlja na jedan od mnoštva troškova koji se javljaju u poljoprivredi, a to je trošak plaća zaposlenih. Plaću možemo definirati kao novčani iznos koji se mjesečno isplaćuje zaposlenima kao naknada za uloženi rad u poslovnom procesu. Plaća se sastoji od osnovne plaće i dodataka na osnovnu plaću. Prosječna isplaćena bruto plaća u 2023. godini u poljoprivredi, ribarstvu i šumarstvu iznosila je 1.358,00 eura, a neto 1.012,00 eura. Prosječna mjesečna bruto plaća po zaposlenome u pravnim osobama Republike Hrvatske za 2023. iznosila je 1.584,00 eura, a neto 1.148,00 eura. Po podacima možemo zaključiti da je puno viša plaća u ostalim djelatnostima nego u poljoprivredi. Bruto plaća pravnih osoba je za 11,66% viša od bruto plaće u poljoprivredi dok je neto plaća viša za 11,34%. U poljoprivredi se korišteni rad prikazuje pomoću AWU (annual work unit ili godišnja jedinica rada), a 1 AWU znači 1800 radnih sati godišnje, odnosno 225 radnih dana godišnje. U Jadranskoj Hrvatskoj se prema podacima FADN sustava godišnje koristi 0,3 jedinice plaćenog rada (AWU), te 1,68 neplaćenog a u Kontinentalnoj 0,2 jedinica plaćenog rada (AWU) i 1,37 neplaćenog.In this paper, emphasis is placed on one of the many costs that occur in agriculture, namely the cost of employee salaries. Salary can be defined as the amount of money that is paid monthly to employees as compensation for the work invested in the business process. The salary consists of the basic salary and supplements to the basic salary. The average gross salary paid in 2023 in agriculture, fishing and forestry was 1,358.00 euros, and the net salary was 1,012.00 euros. The average monthly gross salary per employee in legal entities of the Republic of Croatia for 2023 was EUR 1,584.00, and net EUR 1,148.00. Based on the data, we can conclude that wages in other activities are much higher than in agriculture. The gross salary of legal entities is 11.66% higher than the gross salary in agriculture, while the net salary is 11.34% higher. In agriculture, the work used is shown using AWU (annual work unit), and 1 AWU means 1800 working hours per year, or 225 working days per year. According to FADN system data, 0.3 paid work units (AWU) and 1.68 unpaid work units are used annually in Adriatic Croatia, and 0.2 paid work units (AWU) and 1.37 unpaid work units in Continental Croatia
The effect of temperature on the composition and quality of royal jelly
No full textMatična mliječ je izlučevina podždrijelne i prednjočeljusne žlijezde pčela radilica i predstavlja dobro izbalansiranu hranu kojom pčele hrane ličinke i maticu. Usprkos izuzetnim nutritivnim svojstvima, matična je mliječ osjetljiva na svjetlost, vlagu, zrak te posebice na toplinu. Cilj je ovog rada bio utvrditi utjecaj temperature na sastav i kakvoću matične mliječi primjenom različitih toplinskih tretmana. Istraživanje je provedeno na četiri uzorka matične mliječi prikupljenih iz zajednica sive pčele (Apis mellifera carnica). Uzorci su analizirani metodom infracrvene (FTIR-ATR) spektroskopije u izvornom stanju, nakon izlaganja toplinskom tretmanu (34 °C) u trajanju od 15 minuta te nakon pet dana izloženosti sobnoj temperaturi (24 °C). Rezultati spektralne analize su pokazali kako temperatura ima negativan utjecaj na sastav i kakvoću matične mliječi s obzirom na to da su u svim analiziranim uzorcima uočene spektralne alteracije u vidu pada intenziteta apsorpcijskih vrpci koje ukazuju na promjene (degradaciju) sastava i kakvoće matične mliječi pod utjecajem toplinskih tretmana. Također, rezultati ovog istraživanja ukazuju na to da je matična mliječ osjetljivija na visoke temperature u kraćem vremenskom razdoblju (nakon 15 minuta izloženosti 34 °C), nego na izloženost sobnoj temperaturi kroz duži period (nakon 5 izloženosti 24 °C).Royal jelly is a secretion of the hypopharyngeal and mandibular glands of worker bees and represents a well-balanced food used for feeding larvae and the queen bee. Despite its exceptional nutritional properties, royal jelly is sensitive to light, moisture, air and especially heat. The aim of this study was to determine the influence of temperature on the composition and quality of royal jelly by applying different heat treatments. The research was conducted on four royal jelly samples collected from colonies of the Carniolan bee (Apis mellifera carnica). The samples were analyzed by infrared (FTIR-ATR) spectroscopy as obtained, after exposure to heat treatment (34
°C) for 15 minutes, and after five days of exposure to room temperature (24 °C). The results of the spectral analysis showed that temperature has a negative impact on the composition and quality of royal jelly, given that spectral alterations in terms of decrease in the intensity of absorption bands were observed in all analyzed samples, indicating changes (degradation) in the composition and quality of royal jelly under the influence of heat treatments. The results of this study also indicate that royal jelly is more sensitive to high temperatures in a shorter period of time (after 15 minutes of exposure to 34 °C) than to exposure to room temperature over a longer period (after 5 minutes of exposure to 24 °C)
Spectral profiles of unifloral types of honey from the Republic of Croatia
No full textBudući da med potječe od različitih biljnih vrsta, složen je proizvod raznolikog sastava. Stoga su klasične analitičke metode za određivanje botaničkog podrijetla meda zahtjevne te se u tu svrhu sve više primjenjuju i instrumentalne analitičke metode od kojih se posebno ističe infracrvena (IR) spektroskopija. Cilj je ovog rada bio utvrditi specifične spektralne profile uniflornih vrsta meda s područja Republike Hrvatske te izraditi zbirku IR spektara istih temeljem njihovih karakterističnih apsorpcijskih vrpci. Uz navedeno, cilj je istraživanja bio utvrditi korelaciju između spektralnih podataka i fizikalno-kemijskih parametara meda (udio vode, električna provodnost i pH vrijednost). Prikupljeno je ukupno 226 uzoraka meda s područja 6 županija RH koji su obuhvaćali 23 vrste uniflornog meda. Analiza fizikalno kemijskih parametara provedena je klasičnim analitičkim metodama. IR spektri meda su snimljeni FTIR- spektroskopijom s ATR tehnikom snimanja spektara. Rezultati su pokazali kako su fizikalno- kemijski parametri svih analiziranih uzoraka meda u skladu s međunarodno propisanim kriterijima. FTIR-ATR spektri analiziranih uzoraka meda pokazali su slične integralne spektralne značajke karakterističan za med, ali su se temeljem sličnosti apsorpcijskih vrpci fruktoze, glukoze i saharoze istaknula tri karakteristična spektralna profila. Jednostavnom linearnom regresijom nije utvrđena korelacija između fizikalno-kemijskih parametara i spektralnih podataka što ukazuje na potrebu primjene kemometrijskog modeliranja s ciljem utvrđivanja njihove korelacijske povezanosti.Since honey originates from different plant species, it is a complex product with a diverse composition. Therefore, classical analytical methods for determining the botanical origin of honey are complex, and instrumental analytical methods are increasingly being used for this purpose, of which infrared (IR) spectroscopy stands out. The aim of this study was to determine the specific spectral profiles of unifloral types of honey from the Republic of Croatia and to create a collection of IR spectra based on their characteristic absorption bands. In addition to the above, the aim of this research was to determine the correlation between the spectral data and physicochemical parameters of honey (water content, electrical conductivity and pH value). In total 226 honey samples were collected from 6 counties of the Republic of Croatia, including 23 types of unifloral honey types. Physiochemical analyses were carried out using classical analytical methods. Honey IR spectra were recorded using the FTIR spectroscopy coupled with ATR recording technique. Results have revealed that the physiochemical properties of analysed honey samples were in accordance with internationally prescribed criteria. FTIR-ATR spectra of analysed honey samples showed similar integral spectral features characteristic for honey, but based on the similarity of the absorption bands of fructose, glucose and sucrose, three characteristic spectral profiles were determined. Simple linear regression did not show a correlation between the physicochemical parameters and spectral data which indicates a need to apply chemometric modeling aiming to determine their correlation
The influence of anti-hail nets on the mineral composition of leaves and the chemical composition of must in the Graševina grape variety
No full textCilj rada bio je utvrditi utjecaj protugradnih mreža na kemijski sastav mošta, mineralni sastav lišća te sadržaj klorofila kod sorte Graševina s naglaskom na usporedbu tretmana bijelom i crnom mrežom u odnosu na kontrolu (bez mreže). Pokus je postavljen na vinogradarskom području Klanjec (sjeverozapadna Hrvatska) prema slučajnom blok dizajnu. U prvom uzorkovanju je zabilježen najveći sadržaj dušika kod kontrolnog tretmana (2,35%), a najmanji sadržaj kod bijele mreže (2,07%). Rezultatai drugog uzorkovanja pokazuju najveći sadržaj dušika kod kontrolnog tretmana (2,67%), dok je nešto manji kod bijele mreže (2,51%). U trećem uzorkovanju zabilježen je najmanji sadržaj dušika u usporedbi sa sva tri uzorkovanja (1,58%) kod bijele mreže, dok je nešto malo viši kod tretmana crnom mrežom (1,71%). U prvom uzorkovanju najveći indeks sadržaja klorofila zabilježen je kod kontrolnog tretmana (18,44), dok je kod tretmana crnom mrežom znatno niži (8,14). U drugom uzorkovanju najveći sadržaj klorofila zabilježen je kod bijele mreže (28,46) te nešto niži kod kontrolnog tretmana (23,36). treće uzorkovanje bilježi najveći sadržaj klorofila kod bijele mreže (27,82) te kontrolni tretman bilježi niži sadržaj (23,79). Sadržaj šećera mošta kretao se od 21,32 % Brixa do 18,62 % Brixa. Najveći sadržaj mošta zabilježen je kod tretmana bijelom mrežom. Na temelju dobivenih rezultata možemo zaključiti da primjena protugradnih mreža ima pozitivan utjecaj na uzgoj sorte Graševina.The aim of this study was to determine the effect of anti-hail nets on the chemical composition of must, the mineral composition of leaves, and the chlorophyll content in the Graševina grapevine variety, with a focus on comparing treatments with white and black nets to a control (no net). The experiment was set up in the Klanjec wine-growing region (northwestern Croatia) following a randomized block design. In the first sampling, the highest nitrogen content was recorded in the control treatment (2.35%), while the lowest was observed in the treatment with the white net (2.07%). The results of the second sampling showed the highest nitrogen content again in the control treatment (2.67%), with a slightly lower value recorded under the white net (2.51%). In the third sampling, the lowest nitrogen content among all three samplings was recorded in the white net treatment (1.58%), while a slightly higher value was observed in the treatment with the black net (1.71%). In terms of chlorophyll content index, the highest value in the first sampling was found in the control treatment (18.44), while the treatment with the black net showed a significantly lower value (8.14). In the second sampling, the highest chlorophyll content was recorded under the white net (28.46), followed by the control treatment (23.36). The third sampling showed the highest chlorophyll content in the white net treatment (27.82), while the control treatment had a lower value (23.79). The sugar content in the must ranged from 18.62% to 21.32% Brix, with the highest value recorded in the treatment with the white net. Based on the results obtained, it can be concluded that the use of anti-hail nets has a positive effect on the cultivation of the Graševina variety
Revitalization of open spaces surrounding the “Rakete” residential towers in Zagreb
No full textOvaj završni rad iznosi idejno krajobrazno rješenje revitalizacije otvorenih površina oko stambenog kompleksa „Rakete“ na zagrebačkom Vrbiku. Prostor, unatoč arhitektonskoj prepoznatljivosti, suočen je s infrastrukturnim i funkcionalnim nedostacima otvorenih površina te slabom prepoznatljivošću i povezanošću s urbanim kontekstom. U sklopu rada provedene su višekriterijske analize otvorenih površina te su na temelju tih rezultata odabrane i predložene mjere krajobrazne revitalizacije, očuvanja ambijentalnog identiteta te tehničke modernizacije. Predloženo idejno rješenje usmjereno je na stvaranje funkcionalnog, inkluzivnog i održivog javnog otvorenog prostora, uz smjernice za daljnju provedbu.This final thesis presents a conceptual landscape design for the revitalization of the open spaces surrounding the “Rakete” residential complex in the Vrbik neighborhood of Zagreb. Despite its architectural recognizability, the area faces infrastructural and functional deficiencies in its open spaces, as well as weak visibility and integration within the urban context. Within the scope of the thesis, multi-criteria analyses of the open spaces were conducted, based on which measures for landscape revitalization, preservation of ambient identity, and technical modernization were selected and proposed. The proposed conceptual design is aimed at creating a functional, inclusive, and sustainable public open space, accompanied by guidelines for further implementation
Utjecaj nedostatka dušika, fosfora i kalija na morfologiju korijena ozime pšenice
No full textWheat (Triticum aestivum L.) is a crucial global staple crop for food security, with demand exceeding production by 11.5 million metric tons in 2023/24, highlighting the need to optimize growth and yield. Root morphology plays a key role in nutrient acquisition, and this study investigates how deficiencies in nitrogen (N), phosphorus (P), and potassium (K) affect root traits in two winter wheat cultivars, OS-Olimpija and Sofru, grown under controlled hydroponic conditions. The growth chamber maintained precise environmental conditions: a 16-hour light and 8-hour dark cycle, daytime temperatures at 25°C, nighttime temperatures at 20°C, relative humidity at 70%, and a light intensity of 250 μmol m⁻² s⁻¹. The nutrient solution was continuously aerated. Root traits—including length, width, depth, average diameter, surface area, volume, number of root tips and forks, root length < 0.5 mm, and the percentage of root length < 0.5 mm—were assessed using WinRhizoPro software (Version 2015, Regent Instruments Inc., Quebec, Canada) at four measurement intervals. Potassium deficiency had the most severe impact on root morphology, resulting in shorter root lengths, reduced surface area, and fewer root tips and forks. Phosphorus deficiency hindered fine root development, while nitrogen deficiency also reduced root length, surface area, and volume. Cultivar-specific responses were noted, with OS-Olimpija showing longer roots and larger surface areas, while Sofru developed deeper root systems. These findings emphasize the importance of targeted nutrient management to optimize root architecture, improve nutrient uptake, and enhance crop resilience under nutrient-deficient conditions. The study offers insights into wheat root adaptations to nutrient stress and provides a foundation for future research on nutrient-use efficiency and sustainable wheat production.Pšenica (Triticum aestivum L.) ključna je globalna kultura za sigurnost hrane. Potražnja za pšenicom premašivala je proizvodnju za 11,5 milijuna metričkih tona u 2023. /24. godini, što naglašava potrebu za optimizacijom proizvodnje i prinosa pšenice. Morfologija korijena ima ključnu ulogu u usvajanju hranjivih tvari, a ovo istraživanje istražuje utjecaj nedostataka dušika (N), fosfora (P) i kalija (K) svojstva korijena kod dvije sorte ozime pšenice, OS-Olimpija i Sofru, uzgajanih u kontroliranim hidroponskim uvjetima. Biljke su uzgajane u komorama rast pri 6-satni svjetlosni i 8-satni noćni ciklus, 25°C dnevne i 20°C noćne temperature 70% relativne vlage zraka i 250 μmol m⁻² s⁻¹ intenziteta svjetlosti. Morfološka svojstva korijena, uključujući duljinu, širinu, dubinu, prosječni promjer, površinu, volumen, broj vrhova i grananja korijena, duljinu korijena < 0,5 mm i postotak duljine korijena < 0,5 mm mjerene su pomoću WinRhizoPro (2015, Regent Instruments Inc., Quebec, Kanada) u četiri intervala mjerenja. Nedostatak kalija imao je najznačajniji negativni utjecaj na morfologiju korijena, rezultirajući smanjenom duljinom i površinom korijena te manjim brojem vrhova i grananja korijena. Nedostatak fosfora otežao je razvoj finog korijenja (< 0,5 mm), dok je nedostatak dušika također smanjio duljinu, površinu i volume korijena. Kultivari su se također razlikovali u morfološkim svojstvima korijena, pri čemu je OS-Olimpija pokazala dulje korijene i veću površinu korijena, dok je Sofru razvila dublji korijenov sustav. Ovi rezultati naglašavaju važnost ciljanog upravljanja hranjivim tvarima radi optimizacije razvoja korijena korijena, poboljšanja usvajanja hranjivih tvari i povećanja otpornosti usjeva u uvjetima nedostatka hranjivih tvari. Ovaj rad pruža uvid u prilagodbe korijena pšenice na stres uzrokovan nedostatkom hranjivih tvari i pruža osnovu za buduća istraživanja o učinkovitosti korištenja hranjivih tvari i održivoj proizvodnji pšenice
Chemical changes during the decrystallization of honey using different heat treatments
No full textKristalizacija je prirodno svojstvo meda jer med predstavlja prezasićenu vodenu otopinu šećera te su određene vrste meda ovisno o udjelu i omjeru fruktoze i glukoze sklonije brzoj kristalizaciji. Dekristalizacijom se nerijetko u praksi med dovodi u prvotno tekuće stanje. Cilj je ovog rada bio istražiti kemijske promjene tijekom procesa dekristalizacije meda primjenom različitih toplinskih tretmana. Uzorci 10 vrsta meda u kristaliziranom stanju (med od uljane repice, suncokreta, lipe, amorfe, mandarine, lavande, vrijeska, pajasena, bršljana i bjelogorični medljikovac) su bili izloženi različitim toplinskim tretmanima s obzirom na temperaturu zagrijavanja meda (na 30 °C, 35 °C, 40 °C, 45 °C, 50 °C, 55 °C i 60° C). Kemijski sastav meda je bio analiziran primjenom infracrvene spektroskopije s Fourierovom transformacijom (FTIR) i ATR (prigušena totalna refleksija) tehnikom snimanja spektara. Slične linearne spektralne značajke koje su pratile promjene razine hidratacije glukoze i fruktoze tijekom zagrijavanja meda pokazali su med od uljane repice, suncokreta, mandarine, vrijeska, lipe i bjelogorični medljikovac (pri čemu su med od lipe i medljikovac pod utjecajem toplinskih tretmana bili kemijski stabilniji), dok su med od pajasena i med od amorfe pokazali određeni stupanj nelinearnosti i/ili stagnacije spomenutih kemijskih promjena primarno zbog nepotpune ili neujednačene kristalizacije. Spektralnom je analizom također utvrđeno kako s obzirom na tip i dinamiku kemijskih promjena tijekom procesa dekristalizacije, karakterističan, ali ne u cijelosti istovjetan spektralni profil dijele med od lavande i med od bršljana.Crystallization is a natural property of honey because honey represents a supersaturated aqueous solution of sugar, and certain types of honey, depending on the proportion and ratio of fructose and glucose, are prone to fast crystallization. In practice, decrystallization is a frequently used process that brings honey to its original liquid state. The aim of this work was to investigate chemical changes during the process of decrystallization of honey using different heat treatments. Samples of 10 types of honey in a crystallized state (rape honey, sunflower, lime, false indigo, Satsuma mandarin, lavender, heather, tree of heaven, ivy honey, and honeydew honey) were exposed to different heat treatments with regard to the heating temperature (at 30 °C, 35 °C, 40 °C, 45 °C, 50 °C, 55 °C and 60 ° C). The chemical composition of honey was analyzed using Fourier transform infrared spectroscopy (FTIR) and ATR (attenuated total reflectance) recording technique. Rape, sunflower, Satsuma mandarin, heather, lime and honeydew honey showed similar linear spectral features that followed changes in the level of hydration of glucose and fructose during heating of honey (whereas lime honey and honeydew honey were chemically more stable), while tree of heaven honey and false indigo honey showed a certain degree of non-linearity and/or stagnation of the mentioned chemical changes primarily due to incomplete or ununiform crystallization. Spectral analysis also revealed that, considering the type and dynamics of chemical changes during the decrystallization process, lavender honey and ivy honey share a characteristic, but not entirely identical spectral profile
Impact of cheese brine on sensory evaluation of mozzarella
No full textMozzarella je meki sir iz skupine pasta filata za koji je karakteristično da se nakon
proizvodnje uranja u salamuru, vodenu otopinu soli, CaCl2, solne ili limunske kiseline.
Uranjanjem mozzarelle u salamuru sprječava se isušivanje površine sira uz istovremenu
interakciju sastojaka sira i salamure. Dodatno, kvaliteta salamure kao i dodani sastojci mogu
utjecati na senzorska svojstva sira. Dodatak začina poput češnjaka, ružmarina, origana, bosiljka
te mente najčešće se koristi radi poboljšanja senzorskih svojstava sira. Proizvedene su tri šarže
sira u tipu mozzarelle te je sir pohranjen u tri vrste salamure: 1) vodena otopina limunske
kiseline (0,5 g/L), 2) vodena otopina limunske kiseline (0,5 g/L) i kalcij-klorida (5 g/L), 3) vodena
otopina limunske kiseline (0,5 g/L), kalcij-klorid (5 g/L) i vodenog ekstrakta bosiljka (20 g suhog
bosiljka/L). Senzorna analiza provedena je 0., 5., 10. i 15. dana. Deskriptivnom senzornom
analizom utvrđena je statistička značajnost (p<0,05) za parametre arome, presjeka, teksture,
mirisa i okusa. Najbolje ocjene dodiljenje su mozzarelli u vodenoj otopini limunske kiseline i
kalcijevog klorida.Mozzarella is a soft cheese from the pasta filata group, which is characterized by being
immersed in brine, an aqueous solution of salt, CaCl2, hydrochloric or citric acid, after
production. Immersing the mozzarella in the brine prevents the surface of the cheese from
drying out with the simultaneous interaction of the ingredients of the cheese and the brine.
Additionally, the quality of the brine as well as the added ingredients can affect the sensory
properties of the cheese. The addition of spices such as garlic, rosemary, oregano, basil and
mint is most often used to improve the sensory properties of cheese. Three batches of
mozzarella type cheese were produced and the cheese was stored in three types of brine: 1)
aqueous solution of citric acid (0.5 g/L), 2) aqueous solution of citric acid (0.5 g/L) and calcium
chloride (5 g/L), 3) aqueous solution of citric acid (0.5 g/L), calcium chloride (5 g/L) and water
extract of basil (20 g dry basil/L). Sensory analysis was performed on days 0, 5, 10 and 15.
Descriptive sensory analysis revealed statistical significance (p<0.05) for the parameters of
aroma, section, texture, smell and taste. The best grades are awarded to mozzarella in an
aqueous solution of citric acid and calcium chloride
Assessment and modelling of climate stress tolerance in maize genotypes in a series of targeted environments
No full textTijekom posljednjih nekoliko desetljeća globalne klimatske promjene pred oplemenjivače stavljaju nove izazove u pogledu selekcije genotipova adaptabilnih na sušu i toplinski stres. Ovo istraživanje u prvom koraku istražuje upotrebljivost meteoroloških podataka iz javno dostupnih baza Državnog Hidrometeorološkog zavoda (DHMZ) i Agri4Cast (A4C) i iz njih izračunatih indeksa suše (scPDSI i VPD) i toplinskog stresa (SDD) u odnosu na podatke prikupljene izravno u pokusu (POK), a u svrhu njihovog korištenja prilikom tipizacije okoline. U narednom koraku istražena je primjena okolinskih indeksa u procesu detekcije tolerantnih genotipova. Pomoću različitih statističkih modela ANOVA-e te AMMI analize dalje je istraženo variranje agronomskih svojstava kao i složenost interakcije genotip×okolina (G×E) za 32 genotipa kukuruza različitih skupina zriobe u pogledu učinaka prouzročenih sušom i toplinskim stresom. Kao jedan od novih pristupa istražena je i mogućnost interpretacije G×E interakcija putem procesnog modeliranja pomoću APSIM programskog paketa temeljenog na višegodišnjim meteorološkim podacima. Vrijednosti prinosa višegodišnjih simulacija validirani su sa stvarnim podacima iz poljskih pokusa kako bi se utvrdila pouzdanost predikcije. U zadnjem koraku istražena je mogućnost implementacije tipizacije okoline u klasični oplemenjivački postupak, tj. detekcija genotipova kukuruza tolerantnih na sušu i toplinski stres temeljem rezultata stresnih i normalnih okolina. Validacija podataka o prosječnim dnevnim temperaturama i relativnoj vlazi zraka provedena u ovom istraživanju pokazala je vrlo visoku usporedivost bez obzira na izvor (POK, DHMZ i A4C) i vremenski interval (dan, dekada), a time i upotrebljivost za izračun indeksa okolinskih stresova koji zahtijevaju ove meteorološke podatke. Vrijednosti količine oborine pokazale su slabiju međusobnu povezanost, stoga je u izračunu indeksa suše koji zahtijevaju količinu oborine, poput scPDSI, uputno njezino mjerenje izravno na lokaciji provedbe pokusa. Unatoč manjim razlikama, svi indeksi slično su identificirali najviše i najmanje stresne okoline i pokazali se učinkovitim u tipizaciji okolina na stres suše i visokih temperatura zraka. Veće vrijednosti intervala između polinacije i svilanja (ASI), te niže vrijednosti visine biljaka na istoku (Beli Manastir, Kutjevo, Osijek i Tovarnik) za razliku od zapada zemlje (Rugvica i Šašinovec), kao i značajno smanjenje mase zrna na klipu i prinosa sugerira da su istočne lokacije tijekom 2017. godine pretrpjele stres prouzročen sušom i visokim temperaturama, dok to nije bio slučaj za lokacije smještene na zapadu zemlje. Modelima trofaktorske i dvofaktorske ANOVA-e te AMMI analizom utvrđena je značajnost utjecaja svih glavnih izvora na variranje prinosa, pri čemu je okolina imala najveći utjecaj, a znatno manji interakcija G×E i genotip. AMMI2 biplot ukazuje na nestabilnost okolina i značajan interakcijski doprinos genotipova FAO skupine 300. Genotipovi FAO skupine 400 pokazali su se široko adaptabilnima, pri čemu su tri genotipa pokazala značajan doprinos interakcijskim učincima svojom specifičnom adaptabilnošću spram tri različite okoline. Genotipovi FAO skupina 500 i 600 pokazali su široku adaptabilnost prema prinosnijim okolinama. Procesno modeliranje temeljeno na dugoročnim meteorološkim podacima pokazalo se prikladnim za tipizaciju ciljanih okolina i za simulaciju njihovih proizvodnih potencijala, iako nije uočen obrazac razlika prinosa među pojedinim skupinama zriobe. Povezanost analiziranih agronomskih svojstava i jačine stresa bila je najviša kada je okolinski stres procjenjivan VPD i SDD indeksom. Analizom indeksa tolerantnosti temeljenih na redukciji prinosa zrna između kontrastnih okolina u pogledu sušnog stresa, dvije grupe korištenih indeksa različito rangiraju genotipove spram tolerantnosti na sušu i toplinski stres. Prema prvoj grupi indeksa (GMP, STI, MP i HARM) kao tolerantni izdvojeni su genotipovi 29, 30, 31, dok su prema drugoj grupi indeksa (TOL, SSI, RDY) kao tolerantni izdvojeni 3, 11, 6. Ipak, ako se promatraju iznadprosječni genotipovi prema obje grupe indeksa, onda se mogu izdvojiti genotipovi 13, 15, 12, 14 i 21 kao tolerantni prema obje grupe indeksa.Introduction: Over the last few decades, we have witnessed global climate change and challenges for breeding programs to overcome those scenarios and detect and select drought and heat tolerant genotypes. Therefore, following the hypotheses and objectives, this study in the first part deals with the environment evaluation (envirotyping) using meteorological data for mean daily temperature, relative humidity, and precipitation collected directly in the field and from publicly available sources. They are used to compute several drought and heat indices with the purpose of estimation of the severity of drought and heath stress over six locations and two consecutive years (12 environments) and their impact on agronomic traits. The environmental stress level was also analyzed using several statistical models of ANOVA, as well as AMMI analysis. In addition to the genotype×environment (G×E interaction), it is important for crop production to investigate the three-factor interaction of G×E×M between genotype (G), environment (E), and management (M). Therefore, this research also analyzes the possibility of investigating the G×E×M interactions of four maturity groups (FAO300, FAO400, FAO500, and FAO600) through a process-based crop model. In its final stage, this study explores the possibility of implementing envirotyping in the classical breeding programs through application of drought tolerance indices based on grain yield reduction between contrast environments, as a significant factor in the process of detecting drought and heat-stress tolerant genotypes.
Materials and methods: Meteorological data in the daily and decade (10-day) timeframe were collected from three different sources. The first set of meteorological data was collected directly from the trial (POK), while the other two equivalent data sets were collected from the alternative data sources, Croatian Meteorological and Hydrological Service (DHMZ) and Agri4Cast (A4C). Meteorological data and drought indices calculated from those three data sets were validated by the Pearson correlation coefficient to assess their association. The similarity of the data derived from these three sources enables their usage in the breeding programs focused on drought and heat stress envirotyping scenarios. Envirotyping was conducted through drought (scPDSI and VPD) and heat stress (SDD) indices, calculated from three parallel data sets. The scPDSI index was calculated according to the methodology of Pandžić et al. (2022) and relies on the water balance model (WB) within the observed period (Palmer, 1965). The vapor pressure deficit (VPD) was calculated according to the methodology of Allen et al. (1998) and follows the Perfect Grower (2019) VPD level recommendations. The third one, stress degree days (SDD) index, was calculated according to the Idso et al. (1981). SDD index summarizes the impact of temperatures above 30°C, and unlike the previous two related to drought, SDD indicates the intensity and occurrence of heat stress. Initially, individual ANOVA was used to determine the variation of agronomic traits observed in this study (anthesis-silk interval - ASI, grain moisture, plant height, thousand kernel weight, kernel weight per ear, and grain yield) in 12 environments for 32 maize genotypes of different maturity groups regarding the effects caused by drought and heat stress. Further, three-factorial and two-factorial ANOVA models were used to demonstrate the significance of different structure of main and interaction effects. Additionally, an AMMI analysis with the help of methane software packages (Olivoto and Dal'Col Lúcio, 2019; R Core Team, 2023) was applied to explore the complexity of the G×E interaction for grain yield (AMMI2; Gauch et al., 2008; Gauch, 2013) in terms of the stress level derived from environmental effects in the form of drought and heat stress scenarios. A process-based crop model was conducted through the APSIM software package. APSIM model was calibrated according to long-term meteorological data values from the A4C database, while the agroecological aspect of the soil was adjusted according to the soil type of each experimental site according to the ISRIC (International Soil Reference and Information Centre) database with the help of apsimx software packages (Miguez, 2024; R Core Team, 2023). In the next step, the grain yield derived from simulations were compared with observed values to assess the similarity of the predicted and observed grain yield values. The validation test was made using Pearson's correlation coefficient and root mean square error (RMSE), a commonly used statistical test in terms of process-based crop models (Palsey et al., 2023). The drought and heat stress tolerance detection for 32 maize genotypes of four FAO maturity groups was conducted using the drought tolerance index concept. This study tested seven indices: GMP, STI, MP, HARM, TOL, SSI, and RDY. They are primarily based on measuring the grain yield reduction between stressed and non-stressed conditions. Regarding their interpretation, the panel of 32 genotypes was distributed from the most tolerant to the most sensitive ones according to the growing average values for GMP, STI, MP, and HARM (Fernandez, 1992; Rosielle and Hamblin, 1981; Kristin et al., 1997), and decreasing average values for TOL, SSI, and RDY (Rosielle and Hamblin, 1981; Fischer and Maurer, 1978; Farshadfar et al., 2013).
Results and conclusions: Data validation tests conducted over average daily temperatures and relative humidity values showed high similarity. The data set collected from alternative (DHMZ and A4C) sources show strong relationships with data gathered directly in the POK. Therefore, the study concludes that both alternative data sources can be used to calculate the environmental stress indices that require such meteorological elements as is the case with VPD and SDD. Precipitation values from alternative sources (DHMA and A4C) had a weaker correlation with real values measured directly in the field conditions, especially at the daily timescale, what can limit the reliability of the calculation of indices such as scPDSI. Therefore, to calculate drought indices that require precipitation amount values, it is advisable to provide measurements directly on the field. In 2017 this study observed higher ASI and lower plant height values, as well as significant reduction of kernel weight per ear and grain yield in the eastern (Beli Manastir, Kutjevo, Osijek, and Tovarnik) in contrast to the western part of the country (Rugvica and Šašinovec). This observation suggests that locations in the east part suffered from the stress caused by drought and high temperatures during 2017, while this was not the case for locations in the western part of the country. The models of three-factorial and two-factorial ANOVA and AMMI analysis determined the statistical significance for all major factors of variations to the grain yield. The environment has had the greatest influence, followed by the interaction of G×E and genotype. The AMMI2 biplot indicates environmental diversity and a significant interaction contribution of genotypes gathered in the FAO300. The FAO400 genotypes brought wider adaptability, but it is worth emphasizing that genotypes 9, 11, and 16 show a significant contribution to the interaction effects through their narrow adaptation to specified environments. FAO500 and FAO600 genotypes have shown wide adaptability to more productive environments. The process-based crop model based on long-term meteorological data is a useful tool for characterizing targeted environments and simulating their production potentials, but there was no clear pattern of yield difference among individual maturity groups. The functional association between the analyzed agronomic traits and the intensity of stress was the highest when the environmental stress was assessed by the VPD and SDD index. Through the analysis of drought tolerance indices based on the reduction of grain yield determined between contrasting environments in terms of drought stress, the two groups of indices rank the genotypes differently in terms of tolerance to drought and heat stress. According to the first group of indices (GMP, STI, MP and HARM) genotypes 29, 30, 31 were detected as tolerant, while according to the second group of indices (TOL, SSI, RDY) 3, 11, 6 were detected as tolerant. However, if observed above-average genotypes according to both index groups, then genotypes 13, 15, 12, 14 and 21 can be distinguished as tolerant according to both index groups