Starch bioengineering affects cereal grain germination and seedling establishment

Abstract

SummaryGrain starch phosphorylation and amylose content affect germination and seedling establishment through the combination of direct effects on altered starch granule and molecular structure and indirect effects on amylase activities.

Plant-derived smoke induced activity of amylases, DNA replication and β-tubulin accumulation before radicle protrusion of dormant Avena fatua L. caryopses

“…Earlier publications proposed that GA 3 -induced hydrolysis of starch reserves is a post-germinative event not associated with GA 3 -induced breaking of dormancy (Simpson and Naylor 1962;Foley et al 1993). According to the present views, starch is a major carbon source for generating the energy required for seed germination and early seedling growth (Hong et al 2012;Yan et al 2014;Shaik et al 2014). Moreover, a-amylase was considered as a candidate biomarker for rice seed germination (He and Yang 2013).…”

Structure of branching enzyme- and amylomaltase modified starch produced from well-defined amylose to amylopectin substrates

“…Such enzymatic starch modification may be carried out either by the use of recombinant enzymes acting on purified starches, or alternatively the enzymes may be expressed directly in the starch producing crops by GM technology (Hebelstrup et al, 2015). However, the GM crop approach may sometimes modify the starch to an extend where its function as a storage of biomass and energy is jeopardized so that biological functions such as grain germination and seedling establishment are deficient (Shaik et al, 2014).…”

Defoliation Influences Starch Granule Distribution and Structure in Medicago sativa L. Taproots as Revealed by SEM and TEM

“…Some species appear to synthesize two or all three class sizes of starch granules although at different times [10]. Type A class occurs mostly in cereal endosperm and is large (>15 µm) [10] consisting of regions of densely packed double helix [11]. Type B class size is medium (5-15 µm) occurring in wheat endosperm [10], leaf and tuberous tissues [11].…”

“…Type A class occurs mostly in cereal endosperm and is large (>15 µm) [10] consisting of regions of densely packed double helix [11]. Type B class size is medium (5-15 µm) occurring in wheat endosperm [10], leaf and tuberous tissues [11]. The type C class of starch granules is small (<5 µm) [10] and is also found in legume seeds [11].…”

“…Type B class size is medium (5-15 µm) occurring in wheat endosperm [10], leaf and tuberous tissues [11]. The type C class of starch granules is small (<5 µm) [10] and is also found in legume seeds [11]. There is a discrepancy about the granule size class that is first degraded, but evidence shows that the preferential degradation of a particular starch granule class size is likely tissue and species-specific.…”