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V letu 2021 smo na težkih tleh v Globodolu pri Mirni Peči izvedli poljski poskus, v katerem smo primerjali obračalni plug s 4 plužnimi telesi in rahljalnik na nastavljeni globini obdelave 10 cm in na globini obdelave 15 cm. Rahljalnik je bil opremljen s tremi vrstami nogač z vzmetnim varovanjem pred ovirami, z diski in zobatim valjarjem. Pri delu z omenjenimi stroji smo odčitali delovno hitrost iz traktometra in porabo goriva iz traktorskega terminala. Iz teh podatkov smo izračunali površinsko (ha/h) in časovno storilnost (h/ha) ter porabo goriva na hektar (l/ha). Nato smo tla obdelali z vrtavkasto brano in s podtlačno sejalnico posejali koruzo. Izmerili smo vznik in razdaljo med rastlinami v vrsti. Na koncu smo ročno potrgali storže in izmerili pridelek zrnja. Pri delu z rahljalnikom na obeh globinah 10 in 15 cm je bila večja površinska storilnost ter manjša časovna storilnost kot pri obračalnem plugu. Poraba goriva na hektar je bila največja (19,9 l/ha) pri obračalnem plugu in najmanjša (12,8 l/ha) pri uporabi rahljalnika na globini 10 cm. Pridelek zrnja je bil manjši (6117 kg/ha) na zemljišču z rahljalnikom na globini obdelave 10 cm kot pri ostalih dveh obravnavanjih. Največji (85,3 %) povprečni vznik rastlin je bil izmerjen pri rahljalniku na 10 cm, medtem ko ni bilo večjih razlik v razdalji med rastlinami v vrsti med obravnavanji. In 2021, the field trial was done on heavy soil in Globodol near Mirna Peč, in which reversible plough with 4 ploughing bodies and stubble cultivator with adjusted working depth of 10 cm and 15 cm was compared. Stubble cultivator was equipped with three rows of tines with spring overload protection, discs and tooth roller. When working with these machines the working speed was read from tractometer and the fuel consumption from tractor terminal. Area efficiency (ha/h), time efficiency (h/ha) and fuel consumption per hectare (l/ha) was calculated from these data. Then the soil was cultivated using rotary harrow and the seed was planted with the pneumatic vacuum planter. We measured also plant emergence and the distance between plants in the row. At the end the maize clips were picked up by hand and the yield was calculated. When working with stubble cultivator at both working depths of 10 cm and 15 cm the area efficiency was higher and the time efficiency was smaller compared to reversible plough. Fuel consumption was the largest (19.9 l/ha) at reversible plough and the lowest (12.8 l/ha) at stubble cultivator at 10 cm working depth. On the trial plot where stubble cultivator at 10 cm working depth was used the grain yield was lower (6,117 kg/ha) in comparison to other two treatments. The highest plant emergence (85.3%) was achieved at stubble cultivator at 10 cm depth, while there were no larger differences between treatments regarding distance between plants in the row.

Vitamin A je skupina v maščobi topnih spojin, ki jih človek sam ni zmožen sintetizirati, zato morajo biti široko prisotne v človeški prehrani. Če pride do pomanjkanja vitamina, lahko to vodi v številne težave, med drugim tudi do slepote, kar poleg lakote predstavlja precej velik problem v večini držav v razvoju, kjer škrobna prehrana prebivalstva ne vsebuje zadostnih količin omenjenega vitamina. V ta namen so znanstveniki razvili številne kulturne rastline, ki imajo povečano sintezo in kopičenje provitamina A, ki se v človeškem organizmu pretvori v funkcionalen vitamin A. To so dosegli z metodami biofortifikacije (s konvencionalnim križanjem in z genetskim inženiringom kulturnih rastlin) in s pomočjo 2 pristopov: prekomerne ekspresije in utišanja genov. Uporabljene metode so privedle do znatnega kopičenja karotenoidov v užitnih delih riža, paradižnika, krompirja in koruze ter do očitne spremembe barve plodov le-teh, ki so z večjo vsebnostjo karotenoidov kazale bolj intenzivne odtenke oranžne oz. rumene barve. Za uspešno manipulacijo karotenogeneze pa je ključnega pomena temeljito razumevanje biosintezne poti karotenoidov, katere poznavanje je igralo ključno vlogo pri izbiri posameznih genov. Pri opisanih kulturnih rastlinah so bili geni predvsem bakterijskega izvora (rod Erwinia), uporabljeni pa so bili tudi rastlinski geni, tako endogeni kot tudi geni iz drugih rastlinskih vrst, ki že same po sebi vsebujejo večje količine karotenoidov. Vitamin A is a group of fat-soluble compounds that humans cannot synthesize themselves, so they must be widely present in the human diet. If there is a deficiency of the vitamin, it can lead to many problems, including blindness, which, in addition to hunger, is a big problem in most developing countries where the starchy diet of the population does not contain sufficient amounts of said vitamin. For this purpose, scientists have developed several cultivated crops that have increased synthesis and accumulation of provitamin A, which is converted into functional vitamin A in the human body. This was achieved by biofortification methods (conventional crossing and genetic engineering of cultivated crops) and by means of 2 approaches: overexpression and gene silencing. The methods used led to a significant accumulation of carotenoids in the edible parts of rice, tomatoes, potatoes and corn, and to an obvious change in the colour of their fruits, which, with a higher content of carotenoids, showed more intense shades of orange or yellow colour. For the successful manipulation of carotenogenesis, a thorough understanding of the biosynthesis pathway of carotenoids is crucial and played a key role in the selection of individual genes. In the cultivated plants described, the genes were mainly of bacterial origin (genus Erwinia), but plant genes were also used, both endogenous and genes from other plant species, which by themselves contain larger amounts of carotenoids.

Koruzni hrošč (Diabrotica virgifera virgifera LeConte) je gospodarsko pomemben škodljivec koruze v Evropi in v Severni Ameriki, ki povzroča zelo velike izgube pridelka. V pričujoči disertaciji smo v triletnem poljskem poskusu (2016–2018), ki je potekal na dveh pedoklimatsko različnih lokacijah z naravno gostoto populacije koruznega hrošča, preučili učinkovitost entomopatogenih ogorčic (EO) vrste Heterorhabditis bacteriophora Poinar kot okolju prijaznega načina zatiranja ličink koruznega hrošča. Pri tem smo sočasno primerjali učinkovitost EO z učinkovitostjo dveh pogosto uporabljenih konvencionalnih insekticidov na podlagi teflutrina (Force 1,5 G) iz skupine sintetičnih piretriodov in tiakloprida (Sonido FS 400) iz skupine neonikotinoidov za zatiranje talnih škodljivcev v koruzi. Razvili smo manjši prenosni sistem za vnos EO v tla ob setvi koruze. Ugotovili smo, da je zatiranje ličink koruznega hrošča z vrsto H. bacteriophora značilno vplivalo na manjše izleganje hrošča in da je enako učinkovito kot uporaba granuliranega insekticida teflutrina. Nadalje smo preučili toksičnost proteinskih kompleksov na podlagi egerolizinov OlyA6/PlyB, PlyA2/PlyB in EryA/PlyB iz gliv rodu ostrigarjev (Pleurotus spp.) za koruznega hrošča. Ugotovili smo, da je kompleks OlyA6/PlyB značilno povečal smrtnost odraslih hroščev. Menimo, da je uporaba EO okolju prijazna rešitev za zatiranje koruznega hrošča in da bi kompleksi na podlagi egerolizinov lahko prispevali k razvoju novih bioinsekticidov za zatiranje ciljnih rastlinskih škodljivcev. The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is an economically important pest of maize in Europe and North America, causing considerable yield losses. This dissertation presents results of a three-year field study (2016–2018) conducted in two different pedoclimatic regions naturally infested with a WCR population. We studied the effectiveness of entomopathogenic nematodes (EPN) Heterorhabditis bacteriophora Poinar as an environmentally friendly method against WCR larvae. Concurrently, we compared the effectiveness of EPN to two most commonly used insecticides based on the active ingredient tefluthrin (Force 1,5 G) from the group of synthetic pyrethriods, and the active ingredient thiacloprid (Sonido FS 400) from the group of neonicotinoids, against soil pests in maize. We developed a special system for EPN application into the soil when sowing maize. We found that the treatment with H. bacteriophora significantly affects the hatching of the beetle and was as effective as a tefluthrin treatment. We further evaluated the toxicities of the aegerolysin-based protein complexes OlyA6/PlyB, PlyA2/PlyB and EryA/PlyB from the oyster mushroom (Pleurotus spp.) to adult WCR. We found that the OlyA6/PlyB complex significantly increasing the beetle mortality. We believe that EPN provide an environmentally friendly solution to WCR control and that the aegerolysin-based protein complexes may contribute to the development of new bioinsecticides to control target plant pest.

V proučevanje je bilo vključenih 6 križancev koruze pokovke, in sicer slovenski križanec koruze pokovke 'PopSkom' in 5 tujih križancev iz žlahtniteljskega inštituta v Gleisdorfu, Avstrija. Namen naloge je bil proučiti pridelek in kakovost novega slovenskega križanca koruze pokovke 'PopSkom' in ju primerjati s petimi tujimi križanci ter ugotoviti kakovost oziroma prostornino gotove pokovke ob določeni vlagi v zrnju. Poskus je bil izveden na dveh lokacijah, in sicer v Jablah pri Ljubljani in v Apačah pri Ptuju po metodi naključnega bloka v treh ponovitvah. Slovenski križanec 'PopSkom' ima belo zrnje, križanci iz Gleisdorfa imajo rumeno. V Apačah je imel največji pridelek najzgodnejši križanec 'PopSkom', v Jablah pa najpoznejši križanec GL-2. Po klasifikaciji Zieglerja (2001) imajo vsi križanci debelo zrnje. Vsebnost vlage v zrnju v vseh proučevanih vzorcih vseh križancev je bila med 11,4 in 15,9 %, prostornina gotove pokovke pa med 350 in 1320 ml na maso 30 g surovega zrnja. Največjo povprečno prostornino gotove pokovke je imel križanec GL-2 (1173,7 ml), najmanjšo pa 'PopSkom' (529,4 ml). Glede na prostornino gotove pokovke vseh vzorcev in vseh križancev v mejah med 12 in 14 % vlage v zrnju v prostornini pokanja ni bilo pomembnih razlik. Zato lahko za proučevane križance sklepamo, da je za optimalno prostornino gotove pokovke najprimernejša vsebnost vlage v zrnju v ugotovljenih mejah. The study included 6 popcorn hybrids: the Slovenian popcorn hybrid 'PopSkom' and 5 imported hybrids from the 'Saatzucht, Gleisdorf, Austria. The aim of the investigation was to find out the yield and quality of the new Slovenian popcorn hybrid 'PopSkom' in comparison with five introduced hybrids, and to determine the volume of popping at different grain moisture contents. The experiment was conducted at two locations: at Jable near Ljubljana and at Apače near Ptuj, using the randomised block design in three replications. The Slovenian hybrid 'PopSkom' was characterised by white grains, while the grains of the hybrids from Gleisdorf were yellow. At the Ptuj location, the highest yield was determined for the earliest hybrid 'PopSkom', while at Jable, the most productive was the latest hybrid GL-2. According to the classification of Ziegler (2001) all hybrids had thick grains. The moisture content of the grain in all studied samples of all hybrids ranged between 11.4 and 15.9% and the volume of popping was between 350 and 1320 ml per weight of 30 g of raw grain. The hybrid GL-2 showed the largest average volume of poping (1173.7 ml) and 'PopSkom' the smallest (529.4 ml). Regarding to the volume of the popping of all samples and all hybrids, within the range of the grain moisture between 12 and 14%, there were no significant differences. Taking into account the studied hybrids, we can conclude that these values of grain moisture contents are the most suitable for popping.

Koruza (Zea mays L.) je gospodarsko najpomembnejša poljščina, saj je z njo posejanih skoraj 40 odstotkov slovenskih njiv. Gnojenje je eden od najpomembnejših tehnoloških ukrepov za doseganje velikih pridelkov koruznega zrnja ali silirne mase. Organsko-mineralna gnojila so počasi delujoča gnojila, narejena na osnovi vlažne šote, ki preprečujejo izhlapevanje dušika v ozračje in izpiranje hranil v podtalnico. Poljski poskus z dvema hibridoma koruze 'P9234' (FAO 340) in 'P9911' (FAO 410) je bil izveden na Laboratorijskem polju Oddelka za agronomijo Biotehniške fakultete v letu 2019. Testirali smo vpliv organsko-mineralnih gnojil na agronomske lastnosti koruze. Ugotovili smo, da imajo organsko-mineralna gnojila pozitivni vpliv na večino agronomskih lastnosti koruze. Največji pridelek koruze s 14-odstotno vlažnostjo zrnja (12.306 kg/ha), smo dobili pri hibridu 'P9911', ki je bil pognojen z organsko-mineralnim gnojilom (Superalba Max) in mineralnim gnojilom (UREA 46 % N). Na drugo mesto, s pridelkom 12.124 kg/ha, se je uvrstil isti hibrid, ki je bil pognojen le z organsko-mineralnimi gnojili (Superalba Max, Azotop 30). Poleg pridelka zrnja je pri pridelovanju koruze pomembna tudi masa nadzemnega dela rastline (silirna masa). Največjo maso nadzemnega dela smo dobili pri hibridu 'P9911', ki je bil pognojen le z organsko-mineralnimi gnojili. Ugotovili smo, da ima na delež dušika v nadzemnem delu rastline in zrnu največji vpliv prav gnojenje z dušikom in ne izbor hibrida. Maize (Zea mays L.) is economically the most important crop, as it is used for almost 40% of the crop fields in Slovenia. Fertilization is one of the most important technological measures for achieving large yields of maize grain or silage. Organic-mineral fertilizers are slow-acting fertilizers based on moist peat, which prevent the evaporation of nitrogen into the atmosphere and the leaking of nutrients into groundwater. A field experiment with two maize hybrids 'P9234' (FAO 340) and 'P9911' (FAO 410) took place in the Laboratory Field of the Department of Agronomy of the Biotechnical Faculty in 2019. With the experiment, we tested the influence of the organic-mineral fertilizers on the agronomic properties of maize. Our results show that organic mineral fertilizers have a positive effect on most of the agronomic properties of maize. The highest yield of maize with 14% grain moisture was obtained from the hybrid 'P9911', which was fertilized with organic-mineral fertilizer from the Italian manufacturer and mineral fertilizer. This amounted to 12,306 kg/ha. The same hybrid, but fertilized only with organic-mineral fertilizers ranked second with a yield of 12,124 kg/ha. In addition to the grain yield, the weight of the aboveground part of the plant (silage mass) is also very important in maize production. The highest mass of the aboveground part of maize was obtained from the hybrid 'P9911', which was fertilized only with organic-mineral fertilizers from the Italian manufacturer. We found that rather than the selection of the hybrid, nitrogen fertilization has a higher impact on the nitrogen content in the aboveground part of the plant and the grain.

Pri gnojenju koruze se mora upoštevati količina mineraliziranega dušika (N-min) v tleh tako pred setvijo kot ob dognojevanju. Na njivi v Žitencah v občini Sveti Jurij v Slovenskih goricah je v poskusu, s štirimi obravnavanji (0 – kontrola, 20 + 30 kg N ha-1, 40 + 60 kg N ha-1 in 70 + 80 kg N ha-1 ob setvi in ob dognojevanju v istem zaporedju) analiziran vpliv odmerkov dušika na vsebnost klorofila v listih, silažno maso ter pridelek zrnja. Pridelek zrnja je največji pri odmerku 40 kg N ha-1 ob setvi in 70 kg N ha-1 pri dognojevanju v fazi BBCH 17/19. Vrednost klorofilmerskega odčitka je v fazi BBCH 7 – 9 pri kontroli 501, pri 70 kg N ha-1 pa 610. Korelacijski koeficient med klorofilmerskimi odčitki in pridelkom zrnja kaže 80 odstotno povezanost in čvrsto korelirata. On the field in Žitence, Sveti Jurij v Slovenskih Goricah, a field trial with four treatments 0 – control, 20 +30 kg N ha-1, 40 + 60 kg N ha-1 and 70 + 80 kg N ha-1, before sowing + top dressing at stage 7-9 leaves respectively was done. The effects of nitrogen rates on chlorophyll readings in leaves, silage mass and grain yield were analysed. Grain yield was the significantly highest at 40 kg N ha-1 at sowing time and 60 kg N ha-1 added at BBCH 7-9 stage. Chlorophyll readings in the control treatment were 501, and at the rate 60 kg N ha-1 610. Correlation coefficient between chlorophyll meter readings and yield is showing 80 % correlation, which means strong connection.

V magistrski nalogi smo preverjali odziv celic in protoplastov, pridobljenih iz kalusnega tkiva koruze, na dodatek acetilholina in agonistov acetilholinskih receptorjev. Razvoj kalusa smo inducirali z nacepom mladih poganjkov na gojišče Murashige-Skoog z dodatkom sintetičnega avksina 2,4-D [3 mg/L]. Odzivanje celic in protoplastov s povišanjem [Ca2+]i ob izpostavitvi 60 µM acetilholin-jodidu, nikotinu ali pilokarpin-hidrokloridu smo spremljali prek sprememb v intenziteti fluorescence celic po stimulaciji. Za zaznavo sprememb v [Ca2+]i smo uporabili fluorescenčni indikator za Ca2+ ione, Fluo-4-AM. Ne glede na uporabljeni stimulans v izbrani koncentraciji, pri protoplastih in kalusnih celicah nismo opazili odziva, tj. spremenjene [Ca2+]i, ki bi se statistično značilno razlikoval od negativne kontrole (celice in protoplasti stimulirani s hranilno raztopino). Povišanja [Ca2+]i v času stimulacije so sicer bila prisotna, a so bila najverjetneje posledica mehanskega vzdraženja ob dodatku raztopin. Rezultati torej kažejo na odsotnost acetilholinskih receptorjev pri nediferenciranih celicah koruze oziroma, v primeru njihovega morebitnega obstoja, njihovo neodzivnost na uporabljeno koncentracijo 60 µM acetilholin-jodida, nikotina ali pilokarpin-hidroklorida. Odziv celic in protoplastov koruze na ionomicin je bil neznačilen. Kot pozitivna kontrola za so bile v eksperimentu uporabljene celice HUVEC. Ob izpostavitvi celic acetilholin-jodidu, nikotinu ali pilokarpin-hidrokloridu smo opazili odzive, tj. povišanje [Ca2+]i, ki so bili statistično značilno različni od negativne kontrole (HUVEC stimulirane z zunajcelično raztopino z 10 mM glukozo). Rezultati torej potrjujejo zaznavo 60 µM acetilholin-jodida, nikotina in pilokarpin-hidroklorida ter odzivnost celic HUVEC. Sprememba [Ca2+]i po izpostavitvi HUVEC ionomicinu je bila statistično značilna. In this master thesis we checked the response of the callus-derived maize cells and protoplasts to acetylcholine and acetylcholine receptor agonists. Callus formation was induced by inoculation of young shoots of maize on Murashige-Skoog medium with addition of synthetic auxin 2,4-D [3 mg/L]. We followed the responses of cells and protoplasts to stimulation by 60 µM acetylcholine-iodide, nicotine or pilocarpine-hydrochloride, by alterations in fluorescence intensity. Fluorescent calcium indicator, Fluo-4-AM was used to follow the alterations in [Ca2+]i. We did not observe statistically significant differences between responses of cells and protoplasts to stimulants and negative control (plant cells and protoplasts stimulated by nutrient solution). Increased [Ca2+]i was observed at the time of stimulation, but probably as a consequence of mechanical stimulation when solutions were added to cells and protoplasts. Results show absence of achetilcholine receptors on the dediferentiated maize callus cells or, if expressed, their unresponsiveness to used concentration – 60 µM of acetylcholine-iodide, nicotine or pilocarpine-hydrochloride. The response to ionomycin was uncommon. HUVEC cells were used as positive control. When cells were exposed to acetylcholine-iodide, nicotine and pilocarpine-hydrochloride, statistically significant differenences from negative control (HUVEC stimulated by extracellular solution with 10 mM glucose) were observed in responses, thus increased [Ca2+]i. Results confirm sensing of acetylcholine-iodide, nicotine and pilocarpine-hydrochloride, and responsiveness of HUVEC cells. Alteration in [Ca2+]i after addition of ionomycine to HUVEC was statistically significant.

Obdelavo tal lahko v grobem razdelimo na dva načina. Prvi način obdelave tal in najbolje splošno poznan je konvencionalni način obdelave tal. Za ta način obdelave kot osnovno orodje uporabljajo plug. Preorana njiva še ni primerna za setev, zato je potreben dodaten postopek obdelave. Za pripravo njive na setev uporabimo predsetvenik ali vrtavkasto brano. Ta način obdelave tal je sicer zelo uspešen in uporaben, zahteva pa precej časa za vsa delovna opravila. Kot drugi način obdelave tal se vedno bolj uveljavlja minimalna obdelava tal. Pri minimalni obdelavi tla obdelujemo površinsko. Rastlinske ostanke zgolj mešamo v zgornji plasti njivske površine. Pri tem načinu običajno uporabljamo krožne brane. S krožnimi branami zgornjo plast njivske površine premešamo in razdrobimo na manjše grude in tako pripravimo površino na novo setev. V poskusu, ki smo ga izvedli na Sorškem polju, rezultati kažejo na smotrnost minimalne obdelave tal pri pridelovanju koruze. Razlika med načinoma obdelave se ni razlikovala po številu storžev na rastlino ali pa velikosti rastlin. Največja razlika je bila pri številu rastlin na hektar, kar se kasneje odraža v pridelku sveže mase. Pri minimalni obdelavi tal smo pridelali 63877 kg/ha sveže mase koruze, pri konvencionalni obdelavi tal pa približno 2500 kg več, vendar smo pri minimalni obdelavi tal porabili manj časa in goriva. Generally, we can divide tillage into two major branches. The first option, which is also the most common, is the conventional tillage. This type uses plough as the fundamental tool. The field, which has been ploughed, is not yet suitable for sowing and consequently, an additional processing operation is required. A cultivator or a rotary harrow is used in order to prepare the field. It is true that this tillage option has a very high success rate and is very useful but it does demand a lot of time for all the necessary works. On the other hand, minimum tillage is emerging as an increasingly common alternative. In this case, the field is cultivated by the means of surface treatment. The plant remains are only mixed in the upper layer of the field surface. For this procedure, we normally utilize circular harrows. Circular harrows allow us to mix the upper layer of the field surface and subsequently crumble it into smaller clods, which eventually enables us to prepare the surface for the new sowing. Our experiment, which was conducted on the Sorško polje, proved that the minimum tillage is appropriate for producing corn. There was no difference between the types of tillage when taking into consideration both the number of corncobs per plant and the size of plant. The largest difference occurred in the number of plants per hectare, which is later reflected in the fresh mass production. By using the minimum tillage, we produced 63,877 kg/ha of corn fresh mass while the conventional tillage yielded about 2,500 kg more. However, the minimum tillage required less time and fuel.

Na namakanih in nenamakanih poljih z različno teksturo tal smo z meritvami indeksa listne površine (LAI) spremljali rast hibridov koruze (Zea mays L.). Poskus je bil izveden v letih 2016 in 2017 na območju Murske Sobote (Prekmurje, SV Slovenija), ki je znano po pogostih sušah, padavin je malo oz. so neredne. Poskus je potekal na koruznih poljih podjetja Panvita d.d. (Rakičan, Slovenija) na distričnih rjavih tleh na nekarbonatnih peščeno prodnatih sedimentih na težkih tleh (T) in lahkih tleh (L). Parcele so bile nenamakana (NE) ali namakana (NA) z namakanlim sistemom pivot (na težkih tleh) in sistemom rolomat (na lahkih tleh). Poskus je potekal na štirih poskusnih parcelah (TNE, TNA, LNE in LNA). V letu 2016 je bilo uporabljenih več hibridov koruze (P0216, P9241 PR31Y43) v letu 2017 pa samo en hibrid (P0216). Od začetka vegetacije junija do konca septembra smo merili indeks listne površine (LAI) s ceptometrom LAI-2200 Plant Canopy Analyzer (LiCor, Lincoln, USA). Skozi sezono smo opravili sedem meritev v nerednih intervalih pri katerem smo sledili protokolu meritev LAI v koruzi. Meritve so pokazale tipično sezonsko LAI krivuljo. Največje vrednosti LAI so bile 5,95. Najmanjše vrednosti so bile na lahkih nenamakanih tleh. To nam pove, da je bila koruza prizadeta zaradi sušnega stresa. V obeh sezonah je koruza na TNA in TNE dosegla podobno vrednost LAI. The growth of maize (Zea mays L.) hybrids were monitored in irrigated and non-irrigated fields with different soil texture by applying leaf area index (LAI) measurements. The experiment was performed in 2016 and 2017 in viccinity of Murska Sobota (Prekmurje, NE Slovenia) in the area with frequent droughts which result from low and irregular precipitation. Research sites were established on the maize fields of a company Panvita d.d. (Rakičan, Slovenia) on dystric brown soils on non-calcalerous sandy gravel sediments of two different textures: fine textured soil (FTS) and coarse textured soil (CTS). Fields were either non-irrigated (NI) or irrigated (I) by a pivot (on the plot with FTS) and a hose reel (on the plot with CTS) system. Alltogether we had four treatments in the experimental design (NI-FTS, I-FTS, NI-CTS, I-CTS). Different maize hybrides were sown at the fileds in 2016 (P0216, P9241 PR31Y43 ), whereas one hybrid (P0216 Pioneer) was used for experiment in 2017. In the period from beginning of June to end of September, we measured the leaf area index (LAI), with a LAI-2200 Plant Canopy Analyzer (LiCor, Lincoln, USA). Throughout the season we made 7 measurements at irregular intervals following the protocol for measuring LAI of row crop with a homogeneous canopy. Measurements revealed typical seasonal LAI curves. LAI reached maximum seasonal values of 5.95. The lowest values were observed in non-irrigated coarse textured soil. This indicates that at these fields the growth of maize was supressed by water stress. In both seasons we detected similar LAI in I-FTS and NI-FTS.