Dynamic transcriptome and co-expression analysis suggest the potential roles of small secreted peptides from Tartary buckwheat (Fagopyrum tataricum) in low nitrogen stress response

AbstractA pot experiment was conducted to study the effects of two different low nitrogen tolerant tartary buckwheat varieties’ (Diqing buckwheat (DQ, low nitrogen resistance) and Heifeng 1 (HF, low nitrogen sensitive) response mechanism of organic acids to low nitrogen stress. The results showed that the soil moisture of HF and DQ under low nitrogen treatment decreased 24.2% and 14.32%, respectively when compared with normal nitrogen treatment, and the water consumption of DQ was significantly higher than that of HF at seedling stage. Under low nitrogen treatment, the soil pH value of DQ was 1.44% and 8.44% lower than that of HF at seedling and flowering stages, respectively, the content of NH4+ in DQ soil was 8.2% lower than that of HF at maturity stage, the content of NO3− was significantly higher than that HF 49.2%, 12.9%, and 16.6% in each growth period, respectively. Split plot analysis showed that nitrogen treatment significantly affected the organic acids content in the soil of the buckwheat. The secretion content of organic acids are different among buckwheat cultivars under low nitrogen stress. In the soil of DQ, the content of malonic acid was higher than that of HF by 34.39% at maturity stage; the content of oxalic acid was respectively higher than that of HF by 24.86% and 24.52% at seedling and flowering stages; the content of propionic acid was significantly higher than that of HF by 7.36%, 9.44% and23.47% in each growth period, respectively; and tartaric acid acetic acid also showed the same trend at flowering and maturity stages. In summary, tartary buckwheat may regulate the nutrient availability of rhizosphere soil through the secretion of organic acids in the root system to cope with the low nitrogen stress environment. For the cultivation of tartary buckwheat on poor soil should consider the differences cultivaring barren resistance varieties to increase efficiency in the future.

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Expression Analysis of Nitrogen Metabolism-Related Genes Reveals Differences in Adaptation to Low-Nitrogen Stress between Two Different Barley Cultivars at Seedling Stage

International Journal of Genomics ◽

10.1155/2018/8152860 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Zhiwei Chen ◽

Chenghong Liu ◽

Yifei Wang ◽

Ting He ◽

Runhong Gao ◽

...

Keyword(s):

Gene Expression ◽

Nitrogen Metabolism ◽

Expression Analysis ◽

Nitrogen Fertilizers ◽

Nitrogen Stress ◽

Environmental Damage ◽

Barley Cultivars ◽

Low Nitrogen Stress ◽

Low Nitrogen Tolerance ◽

Low Nitrogen

The excess use of nitrogen fertilizers causes many problems, including higher costs of crop production, lower nitrogen use efficiency, and environmental damage. Crop breeding for low-nitrogen tolerance, especially molecular breeding, has become the major route to solving these issues. Therefore, in crops such as barley (Hordeum vulgare L.), it is crucial to understand the mechanisms of low-nitrogen tolerance at the molecule level. In the present study, two barley cultivars, BI-04 (tolerant to low nitrogen) and BI-45 (sensitive to low nitrogen), were used for gene expression analysis under low-nitrogen stress, including 10 genes related to primary nitrogen metabolism. The results showed that the expressions of HvNIA2 (nitrite reductase), HvGS2 (chloroplastic glutamine synthetase), and HvGLU2 (ferredoxin-dependent glutamate synthase) were only induced in shoots of BI-04 under low-nitrogen stress, HvGLU2 was also only induced in roots of BI-04, and HvGS2 showed a rapid response to low-nitrogen stress in the roots of BI-04. The expression of HvASN1 (asparagine synthetase) was reduced in both cultivars, but it showed a lower reduction in the shoots of BI-04. In addition, gene expression and regulation differences in the shoots and roots were also compared between the barley cultivars. Taken together, the results indicated that the four above-mentioned genes might play important roles in low-nitrogen tolerance in barley.

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