Morphological and physiological plasticity response to low nitrogen stress in black cottonwood (Populus deltoides Marsh.)

Abstract

It is important to evaluate nitrogen use efficiency and nitrogen tolerance of trees in order to improve their productivity. In this study, both were evaluated for 338 Populus deltoides genotypes from six provenances. The plants were cultured under normal nitrogen (750 μM NH4NO3) and low nitrogen (5 μM NH4NO3) conditions for 3 months. Growth, chlorophyll content and glutamine synthetase activity of each genotype were measured. Under low nitrogen, heights, ground diameter, leaf area, leaf and root biomass, and chlorophyll contents were significantly lower than those under normal nitrogen level. Correlation analysis showed that nutrient distribution changed under different nitrogen treatments. There was a negative correlation between leaf traits and root biomass under normal nitrogen level, however, the correlation became positive in low nitrogen treatment. Moreover, with the decrease of nitrogen level, the negative correlation between leaf morphology and chlorophyll levels became weakened. The growth of the genotypes under the two treatments was evaluated by combining principal component analysis with a fuzzy mathematical membership function; the results showed that leaf traits accounted for a large proportion of the variation in the evaluation model. According to the results of comprehensive evaluation of plants under the two treatments, the 338 P. deltoides genotypes could be divided into nine categories, with wide genotypic diversity in nitrogen use efficiency and low nitrogen tolerance. As a result, 26 N-efficient genotypes and 24 N-inefficient genotypes were selected. By comparative analysis of their morphological and physiological traits under the two treatments, leaf traits could be significant indicators for nitrogen use efficiency and nitrogen tolerance, which is of considerable significance for breeding poplar varieties with high nitrogen use efficiencies.

Acclimation of sugar beet in morphological, physiological and BvAMT1.2 expression under low and high nitrogen supply

“…It seems that the growth of sugar beet under N stress was connected to the duration and concentration of N treatments. This result is similar to the results of Chen et al [38], where with reduced N, the root system of black cottonwood adjusted in response to stress reaction, leading to enhanced transfer of substances from the fallen leaves to the roots. However, with extended periods of stress, the substances produced by the leaves was not sufficient for root development; therefore, decelerating the root development.…”

Strong Invasive Mechanism of Wedelia trilobata via Growth and Physiological Traits under Nitrogen Stress Condition

“…Moso bombo is one of the woody plants that improved its morphological and physiological response to stress conditions under ammonium ion (NH 4 ) [25]. Chen et al [26] reported that Populus deltoides significantly promoted root growth that uptakes more N from the soil to improve nitrogen use efficiency under low-N conditions. Invasive plant species also have the capability to live in stressful conditions without any damaging effects because they have strong ecological adaptability [27].…”

A new R2R3-MYB transcription factor CmMYB42 improves low nitrogen stress tolerance of chrysanthemum

“…At present, such situations as the low nitrogen content in most cultivated land, various abiotic stress and low nitrogen use e ciency (NUE) of crops, directly or indirectly lead to the occurrence of nitrogen stress. Accordingly, in order to ensure the normal growth of crops under nitrogen stress, plants have evolved a series of cellular, physiological and molecular mechanisms to adapt to the stress response, such as improving the biosynthesis to alleviate the nitrogen stress response, increasing the content of plant hormones and the expression of stress genes (Imamura et al, 2009;Babst et al, 2019;Chen et al, 2021a;Jin et al, 2021).…”