Potential of Seed Halopriming in Mitigating NaCl-induced Adversities on Nitrogen Metabolism in Legume Crops

Abstract

Background: Salinity is a major threat that impairs legume growth and development worldwide. Therefore, present study was aimed to determine the potential of seed halopriming in relieving NaCl-induced disturbances on nitrogen metabolism of seedlings of six legume crops viz., Lens culinaris, Cajanus cajan, Cicer arietinum, Lathyrus sativus, Vigna radiata and Vigna mungo that were detected to have differential sensitivity to NaCl. Methods: Nonprimed and haloprimed seeds were grown hydroponically under varying NaCl doses for three weeks. Harvested samples were utilised to characterize the toxic effects of NaCl on nitrogen metabolism of nonprimed and haloprimed seedlings. Results: Nonprimed seedlings exhibited reduced nitrate uptake by virtue of which other assimilatory processes of nitrogen fixation were adversely affected. Haloprimed seedlings experienced lesser toxicity under NaCl stress due to elevated activities of nitrate assimilatory enzymes on account of improved nitrate uptake from solution. Lesser ammonium accumulation and lower glutamate dehydrogenase activity implied lesser cytotoxicity in primed seedlings. Based on the trends obtained from tested parameters, nitrogen metabolism was maximally affected in Lens and Cajanus followed by Cicer and Lathyrus. Vigna radiata and Vigna mungo were least affected and therefore may be suggested for cultivation in saline prone agricultural fields after seed halopriming.

Potential of Seed Halopriming in the Mitigation of Salinity Stress during Germination and Seedling Establishment in Durum Wheat (Triticum durum Desf.)

“…and increased ROS scavenging enzymes that promote salinity tolerance (superoxide dismutase, catalase, ascorbate peroxidase, and glutathione peroxidase). Similar results have been reported on seed halopriming with NaCl to alleviate the inhibitory effect of salinity on nitrogen metabolism and DNA biosynthesis in different plant species [ 39 , 40 ]. Recent reports suggest the ameliorative effect of calcium on plants under salinity may be associated with the maintenance of an optimal Na + /K + ratio in the cytoplasm.…”

Echoes of a Stressful Past: Abiotic Stress Memory in Crop Plants towards Enhanced Adaptation

“…Seed priming techniques, as a possible salt stress management approach for developing somatic salt stress memory, have, thus far, been investigated in major crops, such as maize, wheat, and rice [213], Brassica napus L. [138,139] and peppers (Capsicum annuum L.) [140,141]. Research on halopriming (the soaking of seeds in aerated solutions of inorganic salts prior to stress exposure [214]) of seeds with low salt concentration solution, prior to salinity stress, has shown to alleviate the negative effects of NaCl on nitrogen metabolism and DNA damage in different leguminous species [146,147] and induced the upregulation of Giberellic Acid (GA) biosynthesis genes, while improving germination and tolerance in tomato plants [152]. Similarly, halopriming increased the expression of salt-responsive genes attributed to the improved biosynthesis of photosynthetic pigments and decreased levels of oxidative stress markers in bread wheat [154], whereas in rice seeds, it increased the expression of genes associated with ion homoeostasis [150].…”