THE EFFECT OF APPLIED NITROGEN FERTILIZER AND PLANT GROWTH REGULATORS ON WINTER WHEAT (TRITICUM AESTIVUM L.) YIELD AND GRAIN QUALITY

The rate of nitrogen fertilization is the most important factor for plant growth and development which can increase yield and grain quality assurance. But the high rates of applied nitrogen fertilizer combined with high precipitations favor stem elongation and increase risk of cereal lodging. Lodging is a common phenomenon that occurs near harvest time, which can significant decrease both quantity and quality of the yield. Plant growth regulators (PGRs) are widely used for lodging control in winter wheat grown at high nitrogen rates. The present study investigated the effect of PGR and nitrogen fertilization rates on wintet wheat yield and grain protein content.  The field study was conducted at the Agricultural Research and Development Station Turda in 2016 involving eight winter wheat genotypes tested at different rates of applied nitrogen fertilizer, in combination with foliar treatment with trinexapac-ethyl- based plant growth regulator sprayed over the foliage

Effects of climatic changes upon the variability of some productivity characters in winter triticale (X Triticosecale Wittm.)

The global acceleration warm conditions determine an additional stress for plant growth and development stages with a high impact on plant grain yield performances. During five experimental years the climatic conditions varied quite a lot so that the main productivity elements: the number of grains/spike, weight of grains per spike and number of spikes per square meter had different values which influencing final grain yield. Analyzing the relationship between rainfall/temperature and grain yield, including its components, can be observed a strong relation between those especially in the first growth stages (from plant emergence and vegetative restarting in early spring). Climatic conditions have manifested an important influence also in the last phenophases of winter triticale plant with a negative influence on grain yield. Being a process of long duration, grain yield formation is strongly affected by temperature (r=0.89) and rainfall conditions (r=0.45).    

THE INFLUENCE OF SOWING DATE ON YIELD AND QUALITY OF WINTER WHEAT

To study the effect of sowing dates on the grain yield and grain quality of three different winter wheat cultivars, an experiment was conducted at ARDS Turda during 2017-2018. By delaying the sowing date, the winter wheat grain yield decreases, while the grain protein content increases. The biggest loss of grain yield by delaying sowing date was noted to Andrada on sowing date III (6 of Dec. 2017), production decreasing with 1316 kg/ha-1 in comparison with optimal for this variety. Arieşan had the highest grain protein content (16.42 %) and Codru had the highest grain yield in all three experimental sowing dates

The Influence of Flag Leaf Removal and Its Characteristics on Main Yield Components and Yield Quality Indices on Wheat

The flag leaf can be an important vehicle for high grain yield due to its position and photosynthetic characteristics. To identify the most adaptive and stable yielding genotype, three winter wheat genotypes were studied during two experimental years under field conditions to quantify the influence of flag leaf removal in different phenological stages on the grain yield and grain quality. To quantify the influence of the flag leaf on the main yield components, the flag leaf was removed every 7 days, starting from the booting stage to ripening. Chlorophyll a, chlorophyll b, and carotenoids were determined from the removed leaves. As a complex trait, the number of grains/spikes and the weight of the grains/spikes were highly influenced by the flag leaf removal during the early generative stages, causing a yield loss from 9% to more than 40%, depending on the variety. It was established that the photosynthetic pigments were highly influenced by the plant phenology stages and the environmental conditions, especially carotenoids, which act as photoprotective and antioxidant agents under stress conditions. Regarding grain quality, flag leaf removal had a significant influence on the accumulation of grain protein and the wet gluten content, the variability of these quantitative traits being also influenced by the climatic conditions