Effect of L-Ornithine application on improving drought tolerance in sugar beet plants

Abstract

The objective of this research was to determine the foliar application of L-ornithine (0.0, 0.30 and 0.60 mM) as a precursor of polyamines, at vegetative stage was on antioxidant defense and growth of drought stressed sugar beet plants grown under clay and sandy soil conditions. Two water irrigation treatments (80% and 40% Field capacity) were carried out on sugar beet plants grown in pots under greenhouse conditions. Water stress resulted in significantly decrement in growth parameters including root diameter, root and shoot weights per plant compared with corresponding control plants. The results showed that drought stress significantly affected most biochemical characteristics of plants. Photosynthetic pigments contents, free amino acids and peroxidase enzyme activity were decreased, while catalase enzyme activity and lipid peroxidation was increased with drought stress. On the other hand, foliar application of L-ornithine effectively alleviated harmful effects caused by drought stress on root length, root and shoot weights of sugar beet plants, especially under sandy soil conditions. The results cleared that ameliorating the negative effects of drought stress through exogenously applied L-ornithine associated with improved photosynthetic pigments, protein profile, lipid peroxidation, antioxidant enzymes; catalase and peroxidase, total soluble sugars and total amino led to increasing drought tolerance of sugar beet plants.

Salt and Drought Stress Responses in Cultivated Beets (Beta vulgaris L.) and Wild Beet (Beta maritima L.)

“…Capability of germination and seedling growth [17,22,25,30,38] Decline in the root weight and root length Higher root/shoot ratio Decline in the root weight and root length Higher root growth [8,34,38,61] Low water content and small leaf area The initial eight-weeks of growth associated with seedling vigor in sugar beet is considered to be the most crucial stage [79], which determines field emergence and stand establishment. Salt and drought stress negatively affect germination and seedling development in sugar beet [4,80] by affecting ionic balance, resulting in hyperosmotic stress and oxidative damage [25,70,81].…”

“…In addition to salt stress, low soil moisture contents at critical developmental stages such as field emergence and initial seedling establishment could be also detrimental for sugar beet growth [87]. Occurrence of drought stress at vegetative phase can dampen the root and shoot fresh weights and root diameter of sugar beet [8], suggesting that the yield reduction due to drought stress is reciprocated with plant developmental stage as well as severity of water limitation [88]. In a recent work, Skonieczek et al (2018) identified three sugar beet cultivars, which can sustain low moisture at the emergence stage [89].…”

“…The red juice from Swiss chard and red beet is an important source of natural pigments (e.g., betalains), which play a role in free-radical scavenging and have economic value due to their use in the health, pharmaceutical, and food industries [ 5 , 6 ]. Sugar beet stands as the second largest source of refined table sugar after sugar cane, which accounts for approximately 30–40% of global sugar production [ 7 , 8 , 9 ]. In addition to its being the strength of the sugar industry, the processed wastes and other by-products are used for the production of food additives, bioethanol, biodegradable polymers, and biofertilizers [ 10 , 11 ].…”

Exogenous Putrescine Enhances Salt Tolerance and Ginsenosides Content in Korean Ginseng (Panax ginseng Meyer) Sprouts

“…Controlled foliar application of Put can trigger physiological processes and induce osmotic adjustment molecules like proline, total soluble sugars and amino acids in plants [ 35 ]. The role of PAs in the biosynthesis of DNA, RNA, and protein, maintaining plant growth and development, lingering ageing, and protecting the membrane from oxidative damage by removing free radicals in plants were also reported [ 37 ]. Earlier, exogenous Put was reported enhanced salt tolerance by accumulating higher osmolytes, regulating carbon fixation, electron transport, energy and defence pathways in Cynodon dactylon [ 38 ]; eliminating reactive oxygen species in Citrus aurantium [ 39 ]; regulation of photosynthetic pathways in Citrus reticulata × Citrus limetta [ 40 ]; photosynthetic [ 41 ] and root growth [ 4 ] associated proteins in Cucumis sativa .…”

Biological efficacy of agrochemical mikrometsen on sugar beet

“…The yield of sugar beet largely depends on the size of the leaf rosette, its photosynthetic activity, the ability to accumulate and lay assimilates in root crops, and also withstand various kinds of stress [3,4,5]. The growth of the leaf apparatus and root crops during the growing season occurs unevenly.…”