Improving wheat grain yield plays a significant role in ensuring global food security. Wheat production could be increased by the genetic improvement of wheat genotypes where delayed senescence with ...enhanced post‐anthesis capacity and staygreen traits could have an important role. In this study, chlorophyll a fluorescence (ChlF) rise kinetics from the early until late senescence of flag leaves, grain yield and other agro‐morphological characteristics were compared for three winter wheat advanced lines (Osk.4.312/10‐18, Osk.4.330/6‐18 and Osk.4.354/12‐18) under natural drought conditions. The differences between lines were observed when considering the heading date which was 1 and 4 days earlier for the line Osk.4.354/12‐18, than lines Osk.4.312/10‐18 and Osk.4.330/6‐18, respectively. Furthermore, line Osk.4.354/12‐18 had the highest test weight (kg hl−1), while line Osk.4.330/6‐18 showed a tendency of decreased grain yield, compared to the other two lines. Analysis of ChlF transients and several JIP‐test parameters indicated that all three lines had a generally similar course of changes in the photosynthetic performance of flag leaves during senescence under drought conditions. However, at the point when a decrease in photosynthetic performance was initiated, it was slightly less intensive in line Osk.4.354/12‐18 accompanied by longer preservation of functionality and connectivity of PSII units, than in the other two lines, which contributed to its better agronomical performance. These results indicated that even delicate variations in the functioning of the photosynthetic apparatus of the flag leaf during grain filling were agronomically important, especially when plants were exposed to drought stress, and could be used to differentiate otherwise similar wheat genotypes. Even small genotype‐specific differences in the photosynthetic performance of senescing flag leaves, along with earlier heading dates, could assist in the selection of genotypes with a better ability to cope with unfavourable environmental conditions.
Variations in the functioning of the photosynthetic apparatus of the flag leaf during grain filling can be agronomically important, especially when plants were exposed to drought, and could be used to differentiate otherwise similar wheat genotypes. Even small genotype‐specific differences in the photosynthetic performance of senescing flag leaves, slightly improved function of the photosynthetic apparatus, longer integrity of functional PSII units, and extended preservation of the optimal level of energetic connectivity among PSII units during grain filling, along with earlier heading dates, could assist in the selection of genotypes with a better ability to cope with unfavourable environmental conditions.
Due to climate change in recent years, there has been an increasing water deficit during the winter wheat sowing period. This study evaluated six Croatian winter wheat varieties' physiological, ...biochemical, and molecular responses under two drought stress levels at the germination/seedling growth stage. Lipid peroxidation was mainly induced under both drought stress treatments, while the antioxidative response was variety-specific. The most significant role in the antioxidative response had glutathione along with the ascorbate-glutathione pathway. Under drought stress, wheat seedlings responded in proline accumulation that was correlated with the
gene expression. Expression of genes encoding dehydrins (
,
) was highly induced under the drought stress in all varieties, while genes encoding transcription factors were differentially regulated. Expression of
was upregulated under severe drought stress in most varieties, while the expression of
was downregulated or revealed control levels. Different mechanisms were shown to contribute to the drought tolerance in different varieties, which was mainly associated with osmotic adjustment and dehydrins expression. Identifying different mechanisms in drought stress response would advance our understanding of the complex strategies contributing to wheat tolerance to drought in the early growth stage and could contribute to variety selection useful for developing new drought-tolerant varieties.
Wheat is one of the three most important cereals in the world, along with rice and maize. It serves as the primary food and source of energy for about 30–40% of the world’s population. However, the ...low levels of micronutrients in wheat grains can lead to deficiencies of those micronutrients in people whose dietary habits are mostly based on cereals such as wheat. Apart from iron (Fe) and zinc (Zn), a lack of selenium (Se) is also one of the biggest problems in the world. The essentiality of Se has been confirmed for all animals and humans, and the lack of this micronutrient can cause serious health issues. Wheat dominates the world’s cereal production, so it is one of the best plants for biofortification. Due to the fact that agronomic biofortification is not an economical or environmentally acceptable approach, genetic improvement of cereals such as wheat for the enhanced content of micronutrients in the grain represents the most efficient biofortification approach.
Wheat is one of the most common and important cereals in Croatia. Therefore, high selection pressure at wheat breeding program is continually placed on disease, drought and lodging resistance, ...heading date and end-use quality. The aim of the current study was to evaluate the wheat grain productivity and quality, as well as response of wheat seedlings to drought. Five lines of winter wheat with reference variety Kraljica were used for evaluation of desired traits. In general, investigated wheat lines had such good characters as early maturity, high yield, they were smaller in test weight and protein content, but with higher sedimentation value, dough energy and extensibility, compared to reference variety. Overall, lines Osk.4.330/6-18, Osk.3.530/59-18, Osk.4.354/12-18 out yielded the reference variety with regard to the grain yield. According to the results collected in this research, wheat lines differences in germination energy and seedling growth affected by drought were obtained. All lines could offer farmers tolerance to mild drought during sowing and will achieve high yields. Nevertheless, stability and drought tolerance of investigated winter wheat lines in different environments have to be checked in multi-location trials.
Pšenica je jedna od najčešće zasijanih i najvažnijih žitarica u Hrvatskoj. Stoga se u programu oplemenjivanja pšenice kontinuirano stavlja veliki selekcijski pritisak na otpornost na bolesti, sušu, polijeganje, datum klasanja i krajnju kvalitetu zrna. Cilj ovog istraživanja bio je ocijeniti produktivnost i kvalitetu zrna pšenice, kao i odgovor klijanaca pšenice na sušu. Za procjenu željenih svojstava korišteno je pet linija ozime pšenice i kontrolna sorta Kraljica. Uzimajući u obzir ispitivane parametre, linije pšenice u ovom istraživanju imale su određene dobre karakteristike kao što su rano sazrijevanje i visok prinos zrna, bile su manje hektolitarske mase i sadržaja proteina, ali s većom vrijednošću sedimentacijske vrijednosti, energijom tijesta i rastezljivosti u odnosu na kontrolnu sortu. Općenito gledano, linije Osk.4.330/6-18, Osk.3.530/59-18, Osk.4.354/12-18 imale su veće vrijednosti prinosa zrna u odnosu na kontrolnu sortu. Prema rezultatima prikupljenim u ovom istraživanju dobivene su razlike između linija pšenice u energiji klijanja i rastu klijanaca u uvjetima suše. Navedene linije mogle bi poljoprivrednicima ponuditi tolerantnost na blagu sušu tijekom sjetve i postići visoke prinose. Ipak, stabilnost i otpornost na sušu istraživanih linija ozime pšenice u različitim okolinama potrebno je istražiti u pokusima koji uključuju više lokacija.
Fusarium head blight (FHB) is one of the most studied fungal diseases of wheat, causing massive grain yield and quality losses. This study aimed to extend previous studies on the physiological and ...biochemical responses of winter wheat to FHB stress in a controlled environment by focusing on the ascorbate-glutathione pathway (AsA-GSH), photosynthetic efficiency, and stress hormone levels, thus providing insight into the possible interactions of different defense mechanisms during infection. The activity of AsA-GSH metabolism was increased in FHB resistant varieties, maintaining the redox state of spikes, and consequently preserving functional photosystem II. Furthermore, carotenoids (Car) were shown to be the major pigments in the photosystem assembly, as they decreased in FHB-stressed spikes of resistant and moderately resistant varieties, compared to controls. Car are also the substrate for the synthesis of abscisic acid (ABA), which acts as a fungal effector and its elevated content leads to increased FHB susceptibility in inoculated spikes. The results of this study contributed to the knowledge of FHB resistance mechanisms and can be used to improve the breeding of FHB resistant varieties, which is considered to be the most effective control measure.
Fusarium head blight (FHB) is one of the most dangerous diseases of winter wheat, resulting in reduced grain yield and quality, and production of mycotoxins by the
fungi. In the present study, ...changes in the grain metabolomics of winter wheat samples infected with
spp. and corresponding non-infected samples from two locations in Croatia were investigated by GC-MS. A Mann-Whitney test revealed that 24 metabolites detected were significantly separated between
-inoculated and non-infected samples during the variety by treatment interactions. The results confirmed that in grains of six FHB-resistant varieties, ten metabolites were identified as possible resistance-related metabolites. These metabolites included heptadecanoic acid, 9-(Z)-hexadecenoic acid, sophorose, and secolaganin in grains of FHB-resistant varieties at the Osijek location, as well as 2-methylaminomethyltartronic acid, maleamic acid, 4-hydroxyphenylacetonitrile, 1,4-lactonearabinonic acid, secolaganin, and alanine in grains of FHB-resistant varieties at the Tovarnik location. Moreover, on the PCA bi-plot, FHB-susceptible wheat varieties were closer to glycyl proline, decanoic acid, and lactic acid dimer that could have affected other metabolites, and thus, suppressed resistance to FHB. Although defense reactions were genetically conditioned and variety specific, resulting metabolomics changes may give insight into defense-related pathways that could be manipulated to engineer plants with improved resistance to the pathogen.
Fusarium head blight (FHB) is an important disease of wheat and production of mycotoxins makes it a major threat in most wheat-producing areas worldwide. This study aimed to identify the impact of ...epidemic FHB conditions (usage of artificial Fusarium inoculation) on mycotoxin levels in unprocessed wheat. Fusarium levels were monitored at two locations in two treatments (natural infection and inoculation with Fusarium graminearum and F. culmorum) where 13 mycotoxins were evaluated by LC/MS-MS in six winter wheat varieties. Due to favorable conditions for infection with Fusarium fungi during the flowering period at location Tovarnik, wheat varieties had higher disease severity and increased mycotoxin accumulation, compared to Osijek. The most abundant mycotoxins in treatment with inoculation with Fusarium fungi were deoxynivalenol (DON), culmorin (CUL) and hydroxyculmorins. In treatment with natural infection, DON did not exceed maximum limits set by EU. Varieties with lower initial resistance accumulated DON even in naturally infected samples at Tovarnik. These results highlighted the impact of environment variation in the production of Fusarium mycotoxins where FHB initial resistance had a higher impact on the accumulation of mycotoxins than general resistance. Furthermore, wheat samples with higher DON concentration also contained elevated levels of CUL and hydroxyculmorins, showing that CUL can have a possible role in Fusarium virulence. The FHB evaluations provide important information about the genetic resistance of wheat varieties, as well as risk assessment considering mycotoxin accumulation in epidemic conditions.
Three separate field experiments, with different sowing dates, were conducted to determine a suitable sowing date for the highest agromorphological traits and tech- nological quality parameters. The ...results in growing season 2022–23 demonstrated the following: with a sowing date delay (i.e., with the second sowing date occurring on November 4, 2022), the grain yield was significantly advanced when compared to the first sowing date (occurring on October 13, 2022), while the grain yield was significantly increased in eight genotypes (out of a total of twelve of them) on the third sowing date (i.e., on November 14, 2022) when compared to the first. The rea- son for disproportions of grain yield on the first two sowing dates was the attack of barley yellow dwarf virus in autumn that seriously damaged more developed plants pertaining to the first sowing date, whereafter they were also more prone to other wheat diseases. The relative differences concerning the second sowing date with regard to the first one were as follow: an increase by 59.1% concerning the grain yield, by 6.3% concerning the test weight, and by 22.5% concerning a 1000 kernel weight, a decrease by 23.3% concerning the heading date, by 1.2% concerning the protein content, by 2.1% concerning the wet gluten content, and by 2.5% concerning the sedimentation value. The difference in grain yield between the second and the third sowing date amounted to 34.2% due to a premature senescence of plants in later sowing, as a result of increased June temperatures.
Pšenica je jedna od najčešće zasijanih i najvažnijih žitarica u Hrvatskoj. Stoga se u programu oplemenjivanja pšenice kontinuirano stavlja veliki selekcijski pritisak na otpornost na bolesti, sušu, ...polijeganje, datum klasanja i krajnju kvalitetu zrna. Cilj ovog istraživanja bio je ocijeniti produktivnost i kvalitetu zrna pšenice, kao i odgovor klijanaca pšenice na sušu. Za procjenu željenih svojstava korišteno je pet linija ozime pšenice i kontrolna sorta Kraljica. Uzimajući u obzir ispitivane parametre, linije pšenice u ovom istraživanju imale su određene dobre karakteristike kao što su rano sazrijevanje i visok prinos zrna, bile su manje hektolitarske mase i sadržaja proteina, ali s većom vrijednošću sedimentacijske vrijednosti, energijom tijesta i rastezljivosti u odnosu na kontrolnu sortu. Općenito gledano, linije Osk.4.330/6-18, Osk.3.530/59-18, Osk.4.354/12-18 imale su veće vrijednosti prinosa zrna u odnosu na kontrolnu sortu. Prema rezultatima prikupljenim u ovom istraživanju dobivene su razlike između linija pšenice u energiji klijanja i rastu klijanaca u uvjetima suše. Navedene linije mogle bi poljoprivrednicima ponuditi tolerantnost na blagu sušu tijekom sjetve i postići visoke prinose. Ipak, stabilnost i otpornost na sušu istraživanih linija ozime pšenice u različitim okolinama potrebno je istražiti u pokusima koji uključuju više lokacija.
Winter wheat is susceptible to several diseases throughout the vegetative season whereas fungicide treatments are protection used to combat fungal pathogens and to improve plant growth thus ...mitigating grain yield reductions. One of the main diseases is Fusarium head blight (FHB) which can be a huge problem in wheat production. Twelve winter wheat varieties varying in FHB sensitivity were tested for control of FHB using fungicide treatments made in tillering or/and heading stage, with or without inoculation with Fusarium spp. to determine the grain yield response to fungicide application at different growth stages. The grain yield from fungicide treated plots was compared to non-treated plots in two seeding rates and Fusarium inoculated plots in two growing seasons (2019/2020 and 2020/2021). The average area under the disease progress curve (AUDPC) for Type I resistance was 109.48 in 2020 and 99.33 in 2021 year in VI treatment where fungicide application in heading and Fusarium inoculation simultaneously were performed. In VII treatment where only Fusarium inoculation was applied, AUDPC for Type I resistance in 2020 was 371.88 in average, while in 2021 that was 199.18 in average. Wheat varieties treated with a fungicide in the heading stage at the first year of investigation (2020) had higher grain yield, compared to non-treated plots or treated in tillering stage. These results indicated that application of fungicides in heading stage when there is sufficient moisture in May and June may increase chances of profitability from fungicide application at that growth stage. Cumulative rainfall from January till May, at year 2021 had a positive effect on the grain yield, when accumulated rainfall in this period increased chances of getting a higher yield response from fungicide application in the tillering stage. Fungicide applications should always be implemented in combination with sound agronomic management and FHB resistant varieties.
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