EFFECT OF DIFFERENT MEDIA AND IRRIGATION AMOUNTS ON SOME GROWTH CHARACTERISTICS OF PASPALUM (Paspalum vaginatum).

El-Din, M. Nour; Ahmed, H. M. I.; Helaly, A.; Abdalrahman, N. A.

doi:10.21608/jpp.2015.51946

Cited by 1 publication

(1 citation statement)

References 1 publication

(1 reference statement)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Salt is one of the most critical abiotic stressors that inhibit plant growth and development [33], and external morphology and growth status are the most visible indicators of the extent of salt damage to plants [34]. Salt stress has been shown to significantly inhibit the growth of the leaf length, leaf width, and leaf area of apple seedlings [35] and tropical lawns [36]. Chen et al [37] showed that high nitrate stress reduced the leaf length, leaf width, leaf area, and biomass of alfalfa.…”

Section: Growth Parametersmentioning

confidence: 99%

Changes in growth, physiology, and photosynthetic capacity of spinach (Spinacia oleracea L.) under different nitrate levels

et al. 2023

View full text Add to dashboard Cite

Nitrate content is an essential indicator of the quality of vegetables but can cause stress at high levels. This study aimed to elucidate the regulatory mechanisms of nitrate stress tolerance in spinach (Spinacia oleracea L.). We studied the effects of exogenous application of 15 (control), 50, 100, 150, 200, and 250 mM NO3- on spinach growth, physiology, and photosynthesis. The results showed that all the nitrate treatments inhibited the growth of the aerial parts of spinach compared to the control. In contrast, low nitrate levels (50 and 100 mM) promoted spinach root formation, but this effect was inhibited at high levels (150, 200, and 250 mM). Treatment with 150 mM NO3- significantly decreased the root growth vigor. Low nitrate levels increased the chlorophyll content in spinach leaves, whereas high levels had the opposite effect. High nitrate levels also weakened the net photosynthetic rate (Pn), the actual photochemical efficiency of PSII Y(II), and increased non-photochemical quenching (NPQ), reducing photosynthetic performance. Nitrate stress increased the activity of nitrate reductase (NR) and promoted the accumulation of nitrate in spinach leaves, exceeding the health-tolerance limit for nitrate in vegetables, highlighting the necessity of mitigating nitrate stress to ensure food safety. Starting with the 150 mM NO3- treatment, the proline and malondialdehyde content in spinach leaves and roots increased significantly as the nitrate levels increased. Treatment with 150 mM NO3- significantly increased soluble protein and flavonoid contents, while the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) were significantly reduced in leaves. However, spinach could resist nitrate stress by regulating the synthesis of osmoregulatory substances such as proline, thus showing some nitrate tolerance. These results provide insights into the physiological regulatory mechanisms of nitrate stress tolerance and its mitigation in spinach, an essential vegetable crop.

show abstract