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Drought is becoming one of the major constraints in bean production and the selection of drought- tolerant bean genotypes is one of the most important drought adaptation strategies. Drought- tolerant plants develop various physiological and biochemical adaptations under water deficit conditions. These include changes in water use efficiency, pigment content, osmotic adjustment, and photosynthetic activity. The aim of this study was to evaluate drought tolerance among different bean landraces (‘Biser’, ‘Zelenčec’, ‘Trešnjevac’, and ‘Puter’). Plants were grown in river sand and were irrigated with 50 ml of a 1/4-strength Hoagland nutrient solution at the beginning of the experiment. The water content of the control plants was kept at the maximum water capacity of the sand, while in the drought treatment there was no additional irrigation throughout the experiment. During two weeks, five measurements of the stomatal conductance (gsw), boundary layer conductance (gbw), total conductance to water vapor (gtw), transpiration (E), effective quantum yield of PSII photochemistry (ϕPSII), and electron transport rate (ETR) were measured using the LI- 600 poro/fluorometer. Since the onset of drought, ‘Biser’ showed significantly higher gsw, gtw, E and ETR compared to other landraces. These results suggest that ‘Biser’ can maintain normal physiological functions and survive longer under water deficit conditions.

High yields in crop production rely on a constant supply with high amounts of plant nutrients. Thus, inappropriate nutrient supply can cause significant economic losses. Nutrient deficiency alters plant morphological and physiological traits, i.e. cause specific symptoms which could be detected by non- destructive methods, using spectral reflectance analyses. This study aimed to describe and quantify the development of the nutrient deficit (nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg) and iron (Fe)) in common bean (Phaseolus vulgaris L.) using multispectral and chlorophyll fluorescence imaging. Plants were grown in a control nutrient solution and in solutions lacking N, P, K, Mg or Fe and were analyzed every three days during 12 days of growth. Irrespective of measured traits, earliest symptoms and most pronounced changes were detected for K and N deficiency, whereas slowest and least pronounced symptoms development were found in Fe deficiency. From the fluorescence parameters, the earliest and most pronounced response was detected in electron transport rate, which decreased after six days for all treatments compared to control, except for the Fe deficiency. Of the morphological traits, the earliest response reduction in leaf area, found at sixth day in all treatments compared to the control. From multispectral traits, the earliest and most significant differences compared to control were reduction in green leaf index and increase in specific green reflection. These results show that nutrient deficiency could be detected and traced nondestructively using multispectral and chlorophyll fluorescence analysis.

In the face of rapid climate change, drought is considered the most damaging environmental stress to agricultural production. It is estimated that 60% of beans are grown in regions suffering from water shortages, making drought the biggest problem for its production. The selection of drought-resistant genotypes would be very useful for bean production and the agricultural industry. With advances in modern technology, we can effectively combine knowledge of phenotype and genotype to promote breeding programs. At the University of Zagreb Faculty of Agriculture, samples of traditional bean cultivars from Croatia and surrounding countries are preserved. Traditional cultivars represent valuable genetic material that can be used for the selection of desirable agronomic traits. 200 different bean genotypes will be grown in a growth chamber under controlled conditions, inducing two treatments: Control (well-watered plants) and drought stress treatment. High-throughput phenotyping (HTP) techniques will include chlorophyll fluorescence imaging, multispectral imaging, and 3D scanning. Three measurements will be taken over a period of one week and the occurrence of drought and its effect on plant morphological and physiological traits will be monitored. DNA will be isolated from the leaves and genetic analysis of genotypes will be carried out using Microsatellites (SSR). Single Nucleotide Polymorphisms (SNP) markers will be detected using DartSeq technology. A detailed and in-depth analysis of the physiological background of gas exchange capacity will be performed on the selected tolerant and susceptible bean genotypes, including measurements of photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO2 concentration, water use efficiency, light use efficiency, etc. 212 Association mapping will be carried out to find genetic regions associated with phenotypic parameters of chlorophyll fluorescence, gas exchange parameters, and vegetation indices. This research will help to select potentially resistant bean genotypes to drought stress, which may ultimately contribute to the development of breeding programs and agricultural production itself.

Grah (Phaseolus vulgaris L.) je jedna od glavnih leguminoza za ljudsku prehranu. Nedostatak makro i mikro hranjiva je glavni problem za poljoprivrednu proizvodnju. Kako bi biljka provela svoj životni ciklus, uz C, O i H, potrebno je još 13 elemenata: N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, Cl, B i Mo. Nedostatak nekih elemenata smanjuje fotosintezu i inhibira normalno funkcioniranje fotosintetskog sustava. U ovome radu smo istražili utjecaj nedostatka N, P, K, Mg i Fe na fotosintetski sustav kod graha u kontroliranim uvjetima. Pokus je bio postavljen kao hidropon, plutajući sistem u 6 hidroponskih kada volumena 45 L. Svaka hidroponska kada je bila ispunjena sa modifi ciranom Hoaglandovom otopinom i sadržavala 10 biljaka. Jedna grupa biljaka je uzgajana u kompletnoj hranjivoj otopini (kontrola), dok kod drugih tretmana je falilo određeno hranjivo: N, P, K, Mg ili Fe. Tokom pokusa mjerili su se parametri stope fotosinteze (A), stope transpiracije (E), provodljivosti puči za H2 O (gs ), te intercelularne koncentracije CO2 (Ci ). Pri završetku pokusa ustanovljen je sadržaj hranjiva u biljnome materijalu. Nedostatak hranjiva statistički je znatno utjecao na sve parametre izmjene plinova. Najmanje vrijednosti svih parametara u usporedbi sa kontrolom su zabilježene kod biljaka sa nedostatkom K, dok najmanje smanjenje vrijednosti parametara uspoređenih sa kontrolom je zabilježeno kod biljaka sa nedostatkom Fe.

Drought is a significant constraint in bean production, as about 60% of beans are grown in regions with water shortages. In this study, we used high throughput phenotyping (chlorophyll fluorescence imaging, multispectral imaging, 3D multispectral scanning) to continuously monitor the development of drought-induced morphological and physiological symptoms of water deficit. This experiment aims to select the most drought- sensitive plant phenotypic traits which could be used for early detection of drought stress and screening for drought tolerance among common bean genotypes. The experiment consisted of four treatments with ten plants each. Plants were grown in control (fully irrigated sand) and three water deficit treatments (irrigated with 70 mL, 50 mL, and 30 mL of distilled water, respectively). All measurements were performed on five consecutive days, and the last measurement was on the 8-th day of the experiment. The earliest detected symptoms were found on the fourth day of the experiment when a reduction in digital volume, total leaf area, and leaf area index was determined in treatments with 30 mL and 50 mL compared to control and 70 mL. In addition to morphological changes on the fourth day of the experiment, drought-induced treatments caused significant changes in several multispectral traits (specific green and saturation). Chlorophyll fluorescence traits showed to be less affected by drought, and significant changes were found only after prolonged drought stress.

The aim of this study was to determine the effect of hydropriming (dH2O ; PT1) and osmopriming (-0.8 MPa PEG ; PT2) on germination of two common bean cultivars ('Biser' and 'Trešnjevac') under induced drought stress. The germination capacity was tested on the germination paper soaked with dH2O (T1) and -0.6 MPa PEG (T2) for nine days. The results showed that there was no significant difference between two common bean cultivars in terms of germination success, but there were significant differences between pretreatments (PT1 and PT2) and treatments (T1 and T2) in terms of germination success for these cultivars. Seeds of both cultivars germinate significantly faster on dH2O (T1) when pretreatment is PEG -0.8.MPa (PT2), but dH2O (PT1) is a better seed priming technique to use under induced drought stress (-0.6 MPa PEG ; T2).

Bosiljak (Ocimum basilicum L.) je jedna od najvažnijih i najrasprostranjenijih aromatičnih i ljekovitih biljaka, dok je fosfor jedno od najvažnijih, a ujedno i najslabije dostupnih biljnih hranjiva. Arbuskularna mikoriza (AM) prisutna je kod više od 90 % kopnenih biljnih vrsta. U nepovoljnim uvjetima, poput nedostatka fosfora i drugih hranjiva u tlu, AM može značajno povećati efikasnost usvajanja hranjiva te time izbjeći stres nedostatka hranjiva kod biljke domaćina. Cilj ovog rada je utvrditi utjecaj inokulacije AM na primanje fosfora, frekvenciju i intenzitet mikorizacije te na morfološke karakteristike korijena različitih kultivara bosiljka. Pokusom je obuhvaćeno četiri različita kultivara bosiljka ('Genovese', 'Sweet Basil', 'Dark Opal' i varijetet purpurascens) koji su uzgajani u uvjetima niske dostupnosti fosfora (1μmol P L-1) tijekom 60 dana. Tretmane su predstavljali inokulacija korijena AM mikoriznom vrstom Glomus intraradices i kontrola (neinokulirane biljke). Na kraju pokusa određena je koncentracija fosfora u suhoj tvari nadzemnih organa biljke, intenzitet i frekvencija mikorizacije korijena, te morfološke karakteristike korijena bosiljka. AM inokulacija je povećala koncentraciju fosfora u suhoj tvari kod svih mikoriziranih kultivara bosiljka, u odnosu na nemikorizirane kultivare. Najveća prosječna koncentracija P2O5 u ST nadzemnih organa mikoriziranih biljaka utvrđena je kod varijeteta purpurascens. Kultivari bosiljka značajno su se razlikovali u intenzitetu i frekvenciji mikorizacije pri čemu je najjače zaražen bio 'Dark Opal', gdje je intenzitet mikorizacije bio 54,0 %, a frekvencija mikorizacije 70,6 %; a najmanje zaražen var. purpurascens, gdje je intenzitet mikorizacije bio 17,0 %, a frekvencija mikorizacije 36,6 %. Kultivari sa izraženijom frekvencijom i intenzitetom mikorizacije 'Sweet Basil' i 'Dark Opal' su imali slabije razvijen korijenov sustav. Basil (Ocimum basilicum L.) is one of the most important and versatile aromatic and medicinal plant, while phosphorus is one of the most important and frequently limited nutrient for plant growth. Arbuscular mycorrhiza (AM) is present in more than 90 % of terrestrial plant species. In conditions of nutrient deficiency in the soil, AM can significantly increase the efficiency of nutrient uptake, and thus avoid the stress triggered by lack of nutrient in host plants. Aim of current study was to determine the influence of AM on phosphorus uptake, the frequency and intensity of root mycorrhization and morphological characteristics of roots among different basil cultivars. The experiment included four basil cultivars ('Genovese', 'Sweet Basil', 'Dark Opal' and variety purpurascens) which were grown under low phosphorus availability (1 μmol P L-1) for 60 days. The treatments were represented as root inoculation with AM mycorrhizal species Glomus intraradices and uninoculated plants as control. At the end of experiment, shoot phosphorus concentration, the intensity and frequency of root mycorrhization and morphological characteristics of root system were determined. AM inoculation increased phosphorus concentration in dry matter in all inoculated basil cultivars compared to uninoculated cultivars. The highest concentration of P2O5 in the dry matter of plant shoot system was recorded in variety purpurascens. Significant difference in intensity and frequency of mycorrhization where observed among basil cultivars, where strongest infection was determined in 'Dark Opal', with intensity of mycorrhization of 54.0 %, and mycorrhization frequency of 70,6 %; and the least infected was var. purpurascens, with intensity of mycorrhization of 17,0 %, and mycorrhization frequency of 36,6 %. Cultivars with the highest frequency and intensity of mycorrhization, 'Sweet Basil' and 'Dark Opal', had weakest developed root system.