The effect of H2O2 and abscisic acid (ABA) interaction on β-amylase activity under osmotic stress during grain development in barley

Abstract

U N C O R R E C T E D P R O O F

Sugars in crop plants

“…Maltose has been proposed to confer protection against degradation of PSII and the suppression of maltose production by RNA interference of β-amylase results in decreased PSII photochemical efficiency (Kaplan & Guy, 2005). This affects grain filling and is mediated by interactions between β-amylase, abscisic acid (ABA) and hydrogen peroxide (Wei et al, 2009). This affects grain filling and is mediated by interactions between β-amylase, abscisic acid (ABA) and hydrogen peroxide (Wei et al, 2009).…”

“…In barley these factors include genotype, salt stress, nitrogen supply, abiotic stresses such as salt, water, cold and osmotic stress, aphid infestation and heavy metal toxicity (aluminium, copper and cadmium) (Zúniga et al, 1990;Cabrera et al, 1994;Murelli et al, 1995;Olien & Clark, 1995;Teulat et al, 1997;Amer, 1999;Guo et al, 2007;Widodo et al, 2009). The concentration of reducing sugars is affected by osmotic stress during grain development mainly as a result of enhanced β-amylase activity; this also affects source-sink interactions (Wei et al, 2009). The accumulation of soluble sugars has been shown to be associated with osmotic adjustment and has been suggested as a criterion for rapid evaluation of osmotic adjustment capacity in segregating populations, along with leaf osmotic potential and relative water content (Teulat et al, 1997).…”

“…Developing barley grain has also been found to have increased β-amylase activity under stress. This affects grain filling and is mediated by interactions between β-amylase, abscisic acid (ABA) and hydrogen peroxide (Wei et al, 2009).…”

“…The accumulation of soluble sugars has been shown to be associated with osmotic adjustment and has been suggested as a criterion for rapid evaluation of osmotic adjustment capacity in segregating populations, along with leaf osmotic potential and relative water content (Teulat et al, 1997). The concentration of reducing sugars is affected by osmotic stress during grain development mainly as a result of enhanced β-amylase activity; this also affects source-sink interactions (Wei et al, 2009). Salt stress causes an increase in reducing sugars and a decrease in non-reducing sugars, possibly associated with osmotic adjustment (Amer, 1999).…”

Estabelecimento de marcadores bioquímicos para embriogênese somática em Araucaria angustifolia.

“…Em coníferas, alterações nos potenciais osmóticos do meio de cultura, muitas vezes relatadas como estressantes para as células, são necessárias para organização morfológica do ES (Silveira et al, 2004;Stasolla e Yeung, 2003). Durante a maturação, as CEs são expostas a meios de cultura suplementados com altas concentrações de agentes osmóticos e ABA e em muitas espécies vegetais, estas condições resultam em um acúmulo de ERO (Beligni e Lamatina 1999;Wei et al, 2009). As ERO são capazes de atravessar as membranas e alterar diferentes substâncias presentes nas células, como lipídios, proteínas e ácidos nucléicos, e quando na ausência de mecanismos de proteção podem resultar em diversas adversidades como, alterações da mitocôndrias, bloqueio do desenvolvimento das células embriogênicas, depleção do ATP e morte celular programada (Beligni e Lamatina, 1999;Guérin et al, 2001 maior número de inflorescências, redução na altura da planta, aumento no número de raízes secundárias e gravitropismo retardado (Brown et al, 2001).…”