Potassium Deficiency Significantly Affected Plant Growth and Development as Well as microRNA-Mediated Mechanism in Wheat (Triticum aestivum L.)

Abstract

It is well studied that potassium (K +) deficiency induced aberrant growth and development of plant and altered the expression of protein-coding genes. However, there are not too many systematic investigations on root development affected by K + deficiency, and there is no report on miRNA expression during K + deficiency in wheat. In this study, we found that K + deficiency significantly affected wheat seedling growth and development, evidenced by reduced plant biomass and small plant size. In wheat cultivar AK-58, upground shoots were more sensitive to K + deficiency than roots. K + deficiency did not significantly affect root vitality but affected root development, including root branching, root area, and root size. K + deficiency delayed seminal root emergence but enhanced seminal root elongation, total root length, and correspondingly total root surface area. K + deficiency also affected root and leaf respiration at the early exposure stage, but these effects were not observed at the later stage. One potential mechanism causing K + deficiency impacts is microRNAs (miRNAs), one important class of small regulatory RNAs. K + deficiency induced the aberrant expression of miRNAs and their targets, which further affected plant growth, development, and response to abiotic stresses, including K + deficiency. Thereby, this positive root adaption to K + deficiency is likely associated with the miRNA-involved regulation of root development.

Response of Root Growth and Development to Nitrogen and Potassium Deficiency as well as microRNA-Mediated Mechanism in Peanut (Arachis hypogaea L.)

“…In this study, low K promotes both lateral and primary root growth while reduced the total root length. Similar results were also observed in wheat (Thornburg et al, 2020), and almost the opposite result was observed in cotton (Fontana et al, 2020). Although the number of lateral roots and the primary root length increased, the root system was inhibited under K deficiency treatment.…”

“…These N deficiency-induced growth inhibition phenomena were also observed in other plant species, including potatoes (Xie et al, 2018). Studies have also shown that 0.02 mM K + can induce aberrant growth and development in cotton (Fontana et al, 2020) and wheat (Thornburg et al, 2020), which probably due to the reduction of chlorophyll content and photosynthetic capacity.…”

“…Studies have shown that nutrient availability would change the expression of miRNAs and their target mRNAs and then affect the growth and development of plants (Kuicheski et al, 2015). Furthermore, different crops respond differently to nutritional deficiencies (Kuicheski et al, 2015;Fontana et al, 2020;Thornburg et al, 2020). However, the mechanism of miRNAs related to root growth and development in response to nutrient deficiency in peanuts is still unclear.…”

Fungicide Difenoconazole Induced Biochemical and Developmental Toxicity in Wheat (Triticum aestivum L.)

“…The major goal of this study was to investigate the effects of difenoconazole, uptaken by wheat roots, on the growth of whole seedling plants. However, since the growth of the roots is difficult to directly observe with soil culture, this study was conducted by hydroponics according to previously described methods [16,17].…”

“…Seeds of the wheat cultivar Bainong 207 (bred by the Wheat Genetic Improvement Research Center of Henan Institute of Science and Technology) were selected in this study. The seed treatment and planting procedures followed our previous reports [16,17]. Briefly, the wheat seeds were sterilized in 10% hydrogen peroxide (H 2 O 2 ) for 10 min and then rinsed with distilled water 3-5 times to eliminate the H 2 O 2 residues.…”