MORPHO-PHYSIOLOGICAL RESPONSES OF WINTER WHEAT (TRITICUM AESTIVUM L.) TO PLANT GROWTH REGULATORS AND NITROGEN APPLICATIONS

Wheat lodging is a serious problem in cereal production in many areas. Grain yield reductions almost always accompany lodging, with the magnitude of loss dependent on the cultivar, growth stage and severity of lodging. The synthetic plant growth regulators (PGRs) such as chlormequat chloride (CC),  trinexepac-ethyl (TE)  can prevent lodging by reducing stem elongation and improving mechanical strength of the stem. A field experiment was conducted during the 2018-2019 growing season at the experimental field of the Agricultural Research and Development Station, located at Turda, to evaluate the effect of TE and CC on winter wheat morpho-physiological traits such as plant height, LAI, numbers of spikes m-2, lodging and grain yield of three winter wheat genotypes that are tall and with a high lodging susceptibility Arieşan, Apullum and Bezostaia, tested at different rates of applied nitrogen fertilizer in combination with foliar treatment with trinexapac-ethyl and chlorocholine chloride sprayed over the foliage. The influence of the TE treatment and CC treatment on the morpho-physiological traits studied in this experience was not the same for all the genotypes. Both PGR decreased plant height, more TE treatment than CC treatment. CC treatment influenced more than TE the increase of LAI and number of spikes m-2, witch leaded to the increase of grain yield where CC treatment was applied

The Grain Yield Performance and Stability Characters of Several Spring Wheat Genotypes in Transylvanian Plain Conditions

The current study presents some stability parameters (coefficient of variation, environment variation, regression coefficient, deviation from regression, coefficient of determination and ecovalence) of grain yields and the main components of its. Twenty-two spring wheat cultivars were tested in yield trials during three years being analyzed the number of grains per spike, thousand kernel weight and spike density The genotypes: Durom and Marcius indicated over the experimental years, a high stability for grain yield, based on three or more parameters (CV, s2, b, sd2) and a good adaptation. Corso and Henica genotypes have a good stability for number of grains per spike with a medium number of grains, and TD 1524-71 is the most unstable genotype for thousand kernel weight. Regarding the correlation between stability parameters for analyzing characters there is a different and additional reaction according to differently performance of genotype