Elena Roșculete

The flag leaf is very important in the life of cereals, as it contributes to the total amount of photoassimilates, to the grain filling process, and to the dry matter content of the grain at maturity, thus playing an essential role in total productivity.This study presents some experimental results from the SCDA Caracal (Dolj County, Romania) regarding production potential depending on flag leaf area and spike length, in three species of grassy cereals (wheat, triticale and barley), cultivated on the chernozem soil (2022-2024). A three-factorial experience was set up in 3 x 3 x 4 randomized blocks. The influence of the studied factors (species, growing season, flag leaf area) and the interaction species x growing season x flag leaf area on potential production was interpreted. Potential production was greatly influenced by the flag leaf and spike area, both the flag leaf cut in half, the flag leaf cut completely and the spike cut ½ resulted in very significant production reductions. However, the lack of the flag leaf or its reduction did not lead to a major reduction in production, as has been recorded in some literature studies.

Mitotic division is the process of cell growth and division that allows a plant to develop from a single cell into a mature plant. This study presents several aspects regarding mitotic activity in some pea genotypes cultivated on chernozem soil at SCDA Caracal. The mitotic index can fluctuate throughout the day, often showing peaks at certain times due to daily rhythms in cell division activity. The mitotic activity in pea root meristems was variable, and indicate values ranging from 4.6% to 8.9%, depending on the genotype and time. Thus, the most intense mitotic activity was recorded around 8 am, while the lowest value was recorded at 2 pm. The increased mitotic activity in the morning indicates that cell division is most active during this period, potentially in response to light or other diurnal cycles. The lowest rate of cell division at 2 pm suggests a period of relative dormancy for the meristematic cells. The observed pattern is typical for plants, as many biological processes, including cell division, are regulated by a circadian rhythm. Factors like light and temperature fluctuations can also play a role in regulating this rhythm. The mitotic index can be used to assess the growth potential of different pea genotypes.

Nitrogen is one of the most essential nutrients for agricultural crops, and optimizing nitrogen fertilization enables the achievement of high yields and improved quality. In this context, the aim of this study was to identify the nitrogen form that influences wheat yield the most significantly, as well as the cultivars that respond positively to specific forms of nitrogen fertilization, in order to provide recommendations regarding cultivar selection and the appropriate technological approach for chernozem soils in southern Romania. Over a period of three agricultural years (2021–2022, 2022–2023, 2023–2024), 36 winter wheat cultivars were tested under three distinct fertilization conditions, nitrate nitrogen, ammonium nitrogen, and nitrate + ammonium nitrogen, each applied at three different rates: 120 kg·ha⁻¹ active substance (a.s.), 150 kg·ha⁻¹ a.s., and 170 kg·ha⁻¹ a.s. The comparative performance of each cultivar relative to the others was evaluated using the Newman–Keuls multiple-range test. The coefficient of variation (CV) of the obtained yields was used to determine yield stability, and its correlation with yield levels allowed for the identification and recommendation of cultivars that simultaneously demonstrated high yields (above average) and good or moderate stability. Sole application of ammonium nitrogen significantly reduced yield by 3.34% (from 70.66 Q/ha to 68.3 Q/ha), while the nitrate+ammonium combination showed a non-significant yield increase compared to nitrate nitrogen alone (+0.65%, p > 0.05). Among the tested cultivars, Sacramento was identified as the most productive, showing statistically significant superiority for Ct1—the most commonly grown wheat cultivar Glosa—as well as for control 2 (Ct2), which represented the average yield of all tested cultivars under all nitrogen fertilization treatments.

Nitrogen is one of the most essential nutrients for agricultural crops, and optimizing nitrogen fertilization enables the achievement of high yields and improved quality. In this context, the aim of the study was to identify the nitrogen form that significantly influences wheat yield, as well as the cultivars that respond positively to specific form of nitrogen fertilization, in order to provide recommendations regarding cultivar selection and the appropriate technological approach for chernozem soils in southern Romania. Over a period of three years (2021–2024), 36 winter wheat cultivars were tested under three distinct fertilization conditions: nitrate nitrogen, ammonium nitrogen, and nitrate + ammonium nitrogen, each applied in three different rates: 120 kg/ha a.s. (active substance), 150 kg/ha a.s., and 170 kg/ha a.s. The comparative performance of each cultivar relative to the others was evaluated using the Newman-Keuls multiple range test. The coefficient of variation (CV) of the obtained yields was used to determine yield stability, and its correlation with yield levels allowed for the identification and recommendation of cultivars that simultaneously demonstrated high yields (above average) and good or moderate stability. Among the tested cultivars, Sacramento was identified as the most productive, showing statistically significant superiority compared to both controls under all nitrogen fertilization treatments.

For 2 years, in the hilly area of south-western Romania, a single-plant experiment was set up for maize, with 4 foliar fertilization variants: V1 = untreated control; V2 = Treatment 1 at BBCH 14-18 (maize with 4-6 leaves) with Lebosol products 1 l/ha Zinc700 + 1.5 l/ha Bor; V3 = Treatment 2 BBCH 24-28 (maize with 8-10 leaves) with the same products; V4 = Treatment 1 + Treatment 2. Before the first application (T1) leaf and soil samples were taken, and after the second application (T2) leaf samples were taken from the 4 variants for analysis. The foliar analysis before the first application showed normal values for nitrogen, phosphorus, calcium, magnesium, sulfur, iron, manganese, boron, iron, and molybdenum; low value for potassium; slightly low value for zinc and high value for calcium. After the application of the second treatment, in the leaves, the values of zinc content were much improved, boron remained constant but the molybdenum content decreased a lot. Although at the borderline, the nitrogen content in the leaf at T1 and T2 remained at the normal value, after application of T1 + T2 it decreased from 4.6% before application to 2.96%. ANOVA yield analysis showed that the yield increase of 840 kg/ha at T2 is highly significant compared to the untreated control and that at T1 + T2 of 370 kg/ha is distinctly significant compared to the same control. Although the maize yield was high compared to the control after application of T1, it was not statistically assured. Of the yield and quality elements studied, the most stable were: hectolitre mass, protein content and fat content. Large ranges of values were evident for the mass of 1000 kernels and starch content.

The primary source for production in straw cereals (wheat, triticale and barley) is the accumulation of carbohydrates in the photosynthetic organs, mainly in the leaves. From this point of view, the flag leaf plays a vital role in the development of the grain and therefore it must benefit from protection throughout the growing season. Keeping the flag leaf green is a trait that allows cereals to maintain their photosynthetic capacity for a longer period of time after anthesis, especially under drought and heat stress conditions.This study presents some partial experimental results from the SCDA Caracal (Dolj County, Romania) regarding the influence of the flag leaf on the potential production of straw cereals (wheat, triticale and barley). Thus, the potential production was greatly influenced by the area of the flag leaf and the ear, both the half-cut flag leaf, the fully cut flag leaf and the ½ cut ear resulted in very significant production reductions. Much more significant was the influence of precocity, regardless of the species and the surface of the flag leaf and ear. Medium early and late cultivars showed very significant increases in potential production compared to early cultivars.

Wheat has a great importance as a food product, providing a large part of the carbohydrates and proteins needed by humans and representing more than half of the calories consumed by mankind. The nutritional importance of wheat and its beneficial effects on human health have been emphasized in many studies, both in agricultural and medical fields.In the current climate conditions and the predicted changes, as a result of the global warming phenomenon, drought resistance is a priority objective of wheat breeding programs. A decrease in soil water potential due to drought decreases the mitotic activity and rate of leaf expansion.This study presents some results regarding the mitotic activity (MA) in some varieties of wheat (Triticum aestivum) grown in experiences set up at SCDA Caracal (Romania). Water stress caused a decrease of MA in al genotypes and changes in cell wall integrity. The mitotic index (MI) was an efficient index for detecting the mitotic activity deterioration process, which ranged from 9.2 to 17.6%. There was also some alterations of normal mitosis and appearance of some chromosomal and nuclear abnormalities in wheat cells (disorganized cells, chromosome fragmentation, sticky chromosomes, unequal anaphase, ghost nucleus, etc.), with values ranging from 7.15 to 26.08%.These results suggest a reduction of mitotic activity and increase of oxidative stress in wheat under drought conditions.

In cereals breeding, alongside selection for yield and other features, a valuable additional approach is the breeding of crop ideotypes, plants with certain model characteristics which influence photosynthesis, growth and grain production. In literature, the ideotype concept generally refers to the breeding process, but this does not have to be an exhaustive notion, because is important to seeking the best crop phenotype to grow in specific environments, with defined cropping systems and for intended end uses. These brief overviews present some recent results regarding the wheat plant ideotype and its specific morphological and physiological characteristics. The variability of growing conditions and climate changes trend require the development of wheat cultivars that can adapt efficiently to the available water, withstand increased temperatures and maintain a relatively high yield at the same time. Ideotype breeding is a continuous process because ideotypes are developed to meet the changing needs. Integrating of plant ideotype approach within wheat breeding strategies can lead to create more productive and resilient cultivars that are well adapted to specific pedoclimatic conditions.

Drought is the most limiting environmental factor affecting wheat growth and productivity and thus, breeding for drought tolerance is a main objective for cereal breeders. Progress in drought tolerance breeding of wheat depends upon genetic diversity existing among genotypes about of their responses to different stressors. One of the physiological parameter is the osmotic adjustment can be enhanced through selection and breeding. Osmotic adjustment is the only cellular process that is activated under water stress conditions and that makes it possible to maintain cellular turgor. This study presents some physiological patterns in wheat plants under drought condition, with focus on osmotic adjustment. The used methods included searching of databases, such as Web of Science or Google Scholar, in order to identify relevant results. Crop plants synthesize several osmolytes to provide osmotic balance at the cellular level, and those osmolytes, under drought stress, provide the plants’ osmotic adjustment. Osmotic adjustment is critical for regulating cell turgor for the maintenance of plant metabolic activity, growth, and productivity. Generally, drought tolerant wheat genotypes show a clear response towards osmotic adjustment. This indicates the key role that osmotic adjustment plays in drought tolerance and yield sustainability under drought stress.

The aim of this work was to study how certain applied cropping systems (conventional systems differentiated by fertilization level or sowing season and subsistence farming) influence yield, quality, productivity elements, and morphological characters in a collection of Romanian and foreign wheat cultivars. The following indicators were evaluated: productive potential (yield), quality (test weight, protein content, wet gluten content, deformation index, sedimentation index, and gluten index), as well as other elements that determine yield (number of ears/square meter, thousand kernel weight, number of grains/ear, and weight of grains/ear) and plant height. The results show that the cropping systems influenced all the elements studied except the thousand-kernel weight. The only characteristics influenced by higher nitrogen fertilization were test weight, protein content, wet gluten content, deformation index, and gluten index. The superiority of a delayed conventional system was shown by the number of grains/wheat ear and the deformation index. Protein content was differentiated between the conventional and the subsistence system, but especially between the low-input and the conventional system. Nitrogen supply is the most important factor for determining wheat productivity and grain quality.