Assessment of Biochemical Changes in Spinach (Spinacea oleracea L.) Subjected to Varying Water Regimes

Abstract

It is known that leafy vegetables including spinach (Spinacea oleracea L.) contain relatively high amount of water, therefore, their water requirement during the life cycle is comparatively more than the other vegetables. In addition, there is an association between osmoprotection and antioxidants with reference to drought stress tolerance. Keeping in mind these facts, the present study was conducted to assess the changes in plant growth, osmoprotectants, chlorophyll pigments and activities/levels of antioxidative system in spinach (Spinacea oleracea L.) grown under varying water deficit regimes with 40%, 60%, 80% and 100% field capacity (FC). Imposition of varying water regimes significantly decreased shoot and root fresh and dry weights, shoot plus root lengths, and chlorophyll b contents of spinach plants. Increase in proline, glycinebetaine (GB), total phenolics, ascorbic acid and malondialdehyde (MDA) contents as well as the activities of antioxidant enzymes including superoxide dismutase, peroxidase and catalase were observed in the spinach plants particularly at 40% FC. The most effective level of water stress for elevating the proline, GB and antioxidant levels/ activities was observed at 40% FC followed by 60% FC. Hence, the results of this study suggested that upregulation of antioxidants and osmoprotectants is positively associated with the drought tolerance of spinach which depends on the severity of water stress level. These results can be used to narrow the gap between selection of plant species and requirement of irrigated water for the crops grown on dry land areas. ABSTRAKAdalah diketahui bahawa sayur-sayuran berdaun termasuk bayam (Spinacea oleracea L.) mengandungi jumlah air yang agak tinggi, oleh itu, mereka memerlukan lebih air sepanjang kitaran hidup berbanding sayur-sayuran lain. Di samping itu, terdapat hubungan antara osmoperlindungan dan antioksidan berkaitan toleransi tekanan kemarau. Dengan mengambil kira fakta tersebut, kajian ini dijalankan untuk menilai perubahan dalam pertumbuhan tanaman, osmoperlindungan, pigmen klorofil serta aktiviti/tahap sistem antioksidatif pada bayam (Spinacea oleracea L.) yang ditanam di bawah rejim defisit air berbeza dengan 40%, 60%, 80% dan 100% kapasiti lapangan (FC). Pengenaan rejim air yang berbeza dengan ketara mengurangkan berat segar dan kering pucuk dan akar, panjang pucuk dan akar serta kandungan klorofil b pada pokok bayam. Pertambahan kandungan prolin, glisinbetain (GB), jumlah fenolik, asid askorbik dan malondialdehid (MDA) serta aktiviti enzim antioksida termasuk superoksida dismutase, peroksidase dan katalase telah diperhatikan pada tanaman bayam terutamanya pada 40% FC. Tahap tekanan air paling berkesan untuk meningkatkan tahap/aktiviti proline, GB dan antioksidan diperhatikan pada 40% FC diikuti 60% FC. Oleh itu, keputusan kajian ini mencadangkan pengawalaturan atas antioksidan dan osmoperlindungan dikaitkan secara positif dengan toleransi kemarau oleh bayam yang bergantung pada keterukan aras tekanan air. Keputusan ini boleh digunakan unt...

Comparative analysis of the relationship between morphological, physiological, and biochemical properties in spinach (Spinaceaoleracea L.) under deficit irrigation conditions

“…Besides, the fact that the study was carried out in the winter period and the air was turned off affected the light intensity and changes occurred between the periods. In a water constraint study in spinach, it has been reported that chlorophyll a and b content decreases as drought severity increases (Jabeen et al, 2019). In previous studies, similar results were observed by Akram et al (2016) there were significant differences between the pots in the first three harvests, there was no significant difference between the pots in the final harvest ( Figure 3e).…”

“…As a result of the increased water deficit in spinach, H2O2 increases occurred and became an important criterion for measuring the effect of stress. It has been reported that the content of H2O2 increases with increasing drought stress in spinach (Jabeen et al, 2019). MDA content was found high in all harvests and severe and moderate water constraints.…”

“…Since spinach has a high water content, irrigation is necessary for increasing yield and quality in many regions. On the other hand, suitable irrigation programs should be determined in arid and semiarid areas, under limited irrigation conditions (Leskovar et al, 2012;Xu and Leskovar, 2015;Ekinci et al, 2015;Jabeen et al, 2019). As in many vegetables, it is obvious that there will be changes in morphological, physiological, and biochemical contents as a result of water stress in spinach.…”

Iron–Lysine Mediated Alleviation of Chromium Toxicity in Spinach (Spinacia oleracea L.) Plants in Relation to Morpho-Physiological Traits and Iron Uptake When Irrigated with Tannery Wastewater

“…Spinacia oleracea is a worldwide cultivated vegetable crop because of its relative high growth rates, its increased production of biomass and its use of heavy metals and other important soil nutrients [31,32]. Furthermore, S. oleracea has been extensively investigated on the basis of these distinctive features to analyze its growth performance and stress responses to various heavy metals [11,33]. Wastewater irrigation, however, is a common practice in different regions of the world where water shortages are extremely prominent and irrigation puts tremendous pressure on crop quality and yield [6,11,34].…”

Thiamin stimulates growth and secondary metabolites in turnip (Brassica rapa L.) leaf and root under drought stress

“…Optimum water availability is one of the major ecological factors that affect the growth and development of plants (Ashraf et al 2010, Jabeen et al 2019). In contrast, if plants are subjected to water deficit conditions, they show stunted growth (Ahammed et al 2020a, 2020b).…”