Physiological response to potassium deficiency in three sweet potato (Ipomoea batatas [L.] Lam.) genotypes differing in potassium utilization efficiency

Abstract

Potassium (K ? ) is an essential mineral element affecting plant growth and development. The aim of this study was to investigate the physiological response to K ? deficiency in three sweet potato (Ipomoea batatas [L.] Lam.) cultivars with differing K ? utilization efficiencies (KUE). The effects on plant growth status, physiological characteristics, leaf ultrastructure, and photosynthesis were examined. The results showed that K ? deficiency significantly decreased total biomass productivity, root yield, photosynthetic efficiency, and chlorophyll (Chl) content, while increased leaf sucrose and proline content of the three cultivars. K ? deficiency caused acute damage to chloroplast ultrastructure associated with leaf Chl biosynthesis and photosynthate accumulation, and also disturbed the protective enzymes involved in the antioxidative defense system. Compared with the other two cultivars, Xushu32 had higher root yield and better growth performance under K ? deficiency, which was mainly attributed to its high KUE and greater carbohydrate conversion and net photosynthetic efficiency. As a whole, these data suggest that greater tolerance to K ? deficiency among sweet potato genotypes is associated to the capability to mount a stronger physiological stress response during growth.

The Effect of Potassium Deficiency on Growth and Physiology in Sweetpotato [Ipomoea batatas (L.) Lam.] during Early Growth

“…These results suggest that K + deficiency strongly inhibit plant dry weight production, and decreases the root/ shoot ratio in a sweetpotato variety sensitive to K + deficiency. These findings are similar to the results from the field experiment and sand culture experiment (Tang et al, 2015), suggesting that K + deficiency depresses considerable translocation of the assimilation product from leaves to root in the sweetpotato. Chlorophyll is an important index reflecting crop senescence and photosynthetic capacity.…”

“…The two cultivars were screened from 31 materials according to their K + utilization efficiencies and K + sensitivity index (relative root weight) (Tang et al, 2014). In the following field experiment, it has been proved that 'Xushu 32' has a higher total biomass productivity and root yield, as well as higher protective enzyme activities than those of 'Ningzishu 1', in K + deficiency condition (Tang et al, 2015).…”

Biostimulant prevents yield loss and reduces oxidative damage in tomato plants grown on reduced NPK nutrition

“…Primary antioxidative defense consists of several enzymatic systems, the most important being superoxide dismutase (SOD, EC 1.15.1.1), ascorbate peroxidase (APX, EC 1.11.1.11) and plant peroxidases (POD, EC 1.11.1.7) that use different phenolic compounds for substrate (Sharma et al 2012). It has been proven that K deficiency increases plant sensitivity to oxidative stress whereby chloroplast degradation and enzyme antioxidative activity increase (Tang et al 2015;Zhao et al 2016). There are numerous data in the literature indicating that N deficiency adversely affects the chlorophyll concentration and photosynthetic activity which automatically results in the growth and yield reduction (Ciompi et al 1996;Huang et al 2004;Zhao et al 2005).…”

Effect of Surface Irrigation Regimes and Potassium Levels on Growth, Physiological Characters and Productivity of Fodder Beet (Beta vulgaris, L.) under Calcareous Soil Conditions

“…Concerning the effect of potassium fertilization on root and foliage fresh weight, plants treated with 171.36 and 114.24 kg K2O/ha had the highest value compared with other potassium treatments and without any significant differences between such two treatments. In this concern (Mofeeda et al, 2019), Tang et al(2015) pointed that K indispensable mineral constituent, intrinsically playing a key role in plant growth and development process.…”