Potassium and storage root development: focusing on photosynthesis, metabolites and soluble carbohydrates in cassava

Abstract

The linkage between K and the development of storage roots in root crops is partially understood, hence this experiment determined some of the mechanisms involved in cassava. The effects of 10, 40, 70, 100, 150 and 200 mg K l−1 fertigation on photosynthetic attributes, soluble carbohydrates, starch, metabolites, growth and yield were studied in a greenhouse. Storage root yield, number of storage roots, stomatal conductance and net photosynthesis reached maximum at 150 mg K l−1. However, soluble carbohydrates and starch in the leaves significantly declined with an increasing concentration of K solution, similarly to the trend of glycerol in the leaves. Conversely, malic acid, citric acid and propionic acid gradually increased reaching maximum at 150, 150 and 70 mg K l−1 respectively. Combined, these results suggest that sugars were transported from the leaves to a stronger sink – the bulking storage roots. This and the increase of intermediate metabolites of tricarboxylic acid cycle provided the energy required for the bulking process and the development of the storage roots. Although the measured parameters indirectly link K to storage root development, they nonetheless form a basis for studies on direct interactions.

Screening high potassium efficiency potato genotypes and physiological responses at different potassium levels

“…In this study, the sucrose content of 'Huayu-5' in the leaves significantly declined as the concentration of K in the soil increased. These findings are congruent with those reported earlier by Omondi et al (2020). However, the sucrose content of 'Zhongshu-19' in the leaves was not significantly different under the different K treatments.…”

“…Soluble sugar content is positively correlated with soil K, so increasing the supply of K increases sugar accumulation (Zushi and Matsuzoe, 1998); additionally, K is beneficial for increasing the dry matter content and improving fruit quality under drought stress (Mohammed, 2018). Therefore, increased K could lead to increased sucrose in the leaves, loading it in the phloem and transporting it to the roots for storage as starch, enhancing the yield of root crops (Omondi et al, 2020). In this study, the sucrose content of 'Huayu-5' in the leaves significantly declined as the concentration of K in the soil increased.…”

Cassava Cultivars Response to Different Levels of Potassium Fertilization under Drip Irrigation and Sandy Soil Conditions

“…treatment was the most effective in encouraging tuber roots yield and tuber roots parameterswith American cultivar of cassava whereas, the lowest value root diameter was obtained by Indonesian cultivar of cassava which received 70kg/K 2 O/fed. During the two growing seasons was presented in Figure (2).Concerning the importance of potassium in cassava production, it is confirmed the potential of applied K-fertilizer for the productivity of root and tuber crops (e.g., cassava) in many studies like and Omondi et al (2019). Data in Fig.…”

Quantitative Assessment of Trace and Macro Element Compositions of Cassava (Manihot esculenta) Storage Roots Enriched with Β-Carotene as Influenced by Genotypes and Growing Locations

“…In Nigeria, about 75 percent of the preschool children and 67 percent of pregnant women are reported to be anemic, and 20 percent of children below five years suffer from zinc deficiency [28]. K plays an important role in the tuberization of cassava because it uses it as a primary osmolyte to osmotically adjust and positively respond to water stress [29]. Therefore, this accounts for its abundance in cassava roots.…”