Study on metal-triggered callose deposition in roots of maize and soybean

Abstract

Callose plays important roles in a variety of processes of plant development, and/or in a response to a range of biotic and abiotic stresses. In the current work we have studied and compared the effect of lead, cadmium and arsenic on accumulation of newly formed callose deposits in the roots of maize and soybean. We observed formation of characteristic callose deposits in the root cell walls, probably associated with plasmodesmata, depending on the type of metal and the plant species investigated. Further, the callose turnover was analysed by measuring of total callose content as well as activities of total β-(1,3)-glucanases in roots. The latter enzymes are responsible for callose depletion, and their possible role during metal stress has previously been proposed. However, neither of these biochemical values appeared to be sufficiently reliable for scoring the altered callose turnover (including local deposits) in plant tissue. The microscopical observations are discussed in light of the biochemical data obtained.

The Activity of Cell-Wall Modifying β-1,3-Glucanases in Soybean Grown in Presence of Heavy Metals

“…The latter are responsible for degradation of the polysaccharide callose as one of the earliest sign of metal intoxication (PIRŠELOVÁ et al, 2011). Results indicate that the callose accumulation is not related to decreased enzymatic activity of glucanases and reinforce the hypothesis that accumulation of callose is primarily dependent on a higher rate of synthesis and/or deposition (PIRŠELOVÁ et al, 2012;. The callose-decomposing glucanases have been rarely studied in the context of heavy metal stress.…”

“…3). Previously PIRŠELOVÁ et al (2012) have described the induction of the overall activity of the glucanases of soybean (cv. Korada) under the action of 500 mg/dm 3 Pb 2+ , and 300 mg/dm 3 Cd 2+ .…”

“…On the other hand, inhibition of the activity was observed for 100 mg/dm 3 As 3+ . In contrast in maize roots no significant changes were observed (PIRŠELOVÁ et al, 2012). Since the total enzyme activity comprises an entire set of isoforms in tissues , we studied the soybean glucanases in in more detail after separation in polyacrylamide gels.…”

Effect of lead on root growth

“…However, the synthesis of callose is not a general pattern in plants in response to Pb, in Zea mays and G. max , low level Pb treatment did not result in any callose deposition in root tissue. Although, these species synthesized callose in response to cadmium or arsenic (Pirselova et al, 2012). It seems that the formation of callose was closely related to the amount of Pb entering the cell, and subsequently the level of stress.…”

Variable dynamics of cadmium uptake and allocation in four soybean cultivars

“…Noteworthy that Gallec is genetically (Socha et al 2015; this study) and also practically (this study) a low-Cd accumulator. Therefore, we conclude that part of Cd ions likely binds to the cell walls on the surface of roots (Cataldo et al 1983;Piršelová et al 2012) but never enters the root. This fits with relatively high tolerance index of this cultivar, too.…”