Redox markers for drought-induced nodule senescence, a process occurring after drought-induced senescence of the lowest leaves in soybean (Glycine max)

Abstract

While the physiological impact of the drought was perceived throughout the shoot, stress-induced senescence occurred only in the oldest leaf ranks. At this stage, a number of drought-induced changes in nodule metabolites were observed but no metabolite or transcript markers of senescence could be detected. It is concluded that stress-induced senescence in the lowest leaf ranks precedes nodule senescence, suggesting that leaves of low photosynthetic capacity are sacrificed in favour of nodule nitrogen metabolism.

Drought‐induced senescence of Medicago truncatula nodules involves serpin and ferritin to control proteolytic activity and iron levels

“…These results are consistent with previous studies in legumes suggesting that nodules are the first organs to be affected by drought stress (Purcell et al ., ; Streeter, ; Ladrera et al ., ). Drought stress affects the process of nitrogen fixation by various factors such as limiting the carbon supply through suppressing CO 2 fixation, increasing accumulation of ureids in the nodule and transporting amino acids (primarily glutamate and aspartate) from leaves to nodules (King & Purcell, ; Ladrera et al ., ; Marquez‐Garcia et al ., ). Because nitrogen fixation is crucial for accomplishing the N demand set by SNF‐dependent plants (Vitousek et al ., ), drought‐stressed legumes may experience severe N deficiency in addition to the water stress.…”

“…It was also reported in M. truncatula and Glycine max that nodules affected by drought stress succumb to early senescence and as such influence nutrient remobilisation (Van de Velde et al ., ; Ladrera et al ., ). Thus, senescence of protein‐rich nodules may extend the useful lifespan of nodules during times where reduced water and carbon supply (Atkins et al ., ; Marquez‐Garcia et al ., ; Yuan et al ., ) limit the nodules’ ability to fix gaseous nitrogen.…”

“…New Phytologist glutamate and aspartate) from leaves to nodules (King & Purcell, 2005;Ladrera et al, 2007;Marquez-Garcia et al, 2015). Because nitrogen fixation is crucial for accomplishing the N demand set by SNF-dependent plants (Vitousek et al, 2013), droughtstressed legumes may experience severe N deficiency in addition to the water stress.…”

Oxidative stress and antioxidative systems: recipes for successful data collection and interpretation

“…However, stress‐induced changes in ascorbate redox state can also be observed, although often under different conditions from those that greatly influence the glutathione pool (Marquez‐Garcia et al . ). Although these pools are functionally coupled under some conditions, they may also work more independently in other circumstances (Foyer & Noctor ).…”

Selection and Breeding of Suitable Crop Genotypes for Drought and Heat Periods in a Changing Climate: Which Morphological and Physiological Properties Should Be Considered?

“…At the next stages of the symbiotic partnership, drought can inhibit development of nodules, and triggers frequently premature nodule senescence. In general, the drought-induced inhibition of the rate of symbiotic nitrogen fixation could be related to several main factors: reduced carbon flux from the host plant leading to low ATP content, decreased shoot nitrogen demand, lower xylem translocation rate due to a decreased transpiration rate, drought-induced changes in nodule oxygen permeability resulting in low oxygen levels, decreased metabolic enzyme activity, and nitrogen feedback inhibition [64,85,86]. The latter is more pronounced in tropical ureide-exporting legumes [87,88], whereas temperate amide exporting legumes are generally more tolerant to drought than the ureide exporters [89].…”