Sodium nitroprusside, cyanide, nitrite, and nitrate break Arabidopsis seed dormancy in a nitric oxide-dependent manner

Abstract

The seeds of many plant species are dormant at maturity and dormancy loss is a prerequisite for germination. Numerous environmental and chemical treatments are known to lessen or remove seed dormancy, but the biochemical changes that occur during this change of state are poorly understood. Several lines of research have implicated nitric oxide (NO) as a participant in this process. Here, we show that dormant seeds of Arabidopsis thaliana (L.) Heynh. will germinate following treatment with the NO donor sodium nitroprusside (SNP), cyanide (CN), nitrite or nitrate. In all cases, the NO scavenger c-PTIO effectively promotes the maintenance of seed dormancy. c-PTIO does not, however, inhibit germination of fully after-ripened seeds, and c-PTIO does not interact directly with nitrite, nitrate or CN. We also show that volatile CN effectively breaks dormancy of Arabidopsis seeds, and that CN is the volatile compound in SNP that promotes dormancy loss. Our data support the hypothesis that NO is a signaling molecule that plays an important role in the loss of seed dormancy.

Burning vegetation produces cyanohydrins that liberate cyanide and stimulate seed germination

“…The mode of action of cyanide in stimulating seed germination remains unclear but is thought to involve reactive oxygen species 32,39 . It has also been proposed that cyanide acts at an initial step in dormancy alleviation and nitrogen oxide is required at a later step 33 . This is interesting given that nitrogen oxides (NO and NO 2 ) have previously been proposed as germination-active components of smoke and can stimulate the germination of E. penduliflora 8 .…”

“…3 h) at relatively high concentration (ca. 1 mM) followed by removal of the cyanide source 32,33 . We tested KCN at various concentrations in a continuous incubation mode and found that it promoted the germination of A. manglesii at concentrations similar to those found effective for glyceronitrile (Fig.…”

Participation of GA3, ethylene, NO and HCN in germination of Amaranthus retroflexus L. seeds with various dormancy levels

“…Sodium nitroprusside (SNP), producing both NO and HCN in the light (Feelisch 1998), releases dormancy of lettuce (Beligni and Lamattina 2000), barley (Bethke et al 2004), Arabidopsis (Bethke et al 2004(Bethke et al , 2006a, A. retroflexus seeds (Liu et al 2011) and Malus domestica embryos (Gniazdowska et al 2007(Gniazdowska et al , 2010. Likewise, HCN released from Fe(II)CN or Fe(III)CN can reduce dormancy in Arabidopsis (Bethke et al 2006b), A. retroflexus seeds (Liu et al 2011) and Malus domestica embryos (Gniazdowska et al 2010). There are no data on the effect of gibberellins, ethylene, NO and HCN on germination of dry stored or stratified A. retroflexus seeds.…”

The role of water channel proteins and nitric oxide signaling in rice seed germination

“…However, NO exerts both beneficial and harmful effects on plants, depending on its concentrations in cells [15]. Several papers have reported that NO is an endogenous regulator of seed dormancy, illustrated by the NO donor compounds breaking dormancy of Arabidopsis seeds [16][17][18] and reducing dormancy of three barley cultivars [17]. Conversely, NO scavengers have been shown to strengthen dormancy of Arabidopsis and barley seeds [17,18], and reduce the stimulative effects of NO donors on seed germination [10,17].…”

“…Several papers have reported that NO is an endogenous regulator of seed dormancy, illustrated by the NO donor compounds breaking dormancy of Arabidopsis seeds [16][17][18] and reducing dormancy of three barley cultivars [17]. Conversely, NO scavengers have been shown to strengthen dormancy of Arabidopsis and barley seeds [17,18], and reduce the stimulative effects of NO donors on seed germination [10,17]. Beligni and Lamattina [10] concluded that NO was involved in light-mediated signaling, such as light stimulation of seed germination, de-etiolation and inhibition of hypocotyl elongation.…”