Rosmarinic acid content and RAPD analysis of in vitro regenerated basil (Ocimum americanum) plants

Various in vitro cultures were established from shoot tips of Ocimum americanum seedlings. Rosmarinic acid content of the in vitro produced plants as well as parent plant were determined by HPLC analysis and subjected to RAPD analysis. MS medium with BA at a concentration of 1 mg/l and 0.25 mg/l IAA supports maximum rosmarinic acid production in plants produced from cultures grown on that medium. RAPD analysis revealed 64 scorable bands from four primers, including six polymorphic bands. The band pattern revealed differences between the parent plant and the in vitro regenerated plants. Certain band changes were found in O. americanum plants regenerated in vitro, suggesting the existence of genetic variation that might affect the biochemical synthesis of plants derived from tissue culture.     

Exogenous Calcium Supplementation Improves Salinity Tolerance in BRRI Dhan28; a Salt-Susceptible High-Yielding Oryza Sativa Cultivar

Journal of Crop Science and Biotechnology - Salinity is one of the most brutal abiotic stressors, commencing a great stumbling block in the way of attaining food security in Bangladesh. Cultivation...     

Response of wheat growth and productivity to exogenous polyamines under lead stress

Polyamines [i.e. spermine (Spm), spermidine (Spd) and putrescine (Put)] antagonistic effects on stress imposed by 2.0 mM lead (Pb²⁺) on growth, yield and its components and changes in the osmoprotectant and endogenous Pb²⁺ concentrations, the contents of some nutrients and tissue health in wheat plants were evaluated. Under the three applied polyamine (PAs) applications, the efficiency of wheat plants to tolerate Pb²⁺ stress in terms of growth and yield characteristics was noticed to varying degrees. The enhancements in osmoprotectant concentrations and plant health [in terms of relative water content (RWC) and membrane stability index (MSI)], and reductions in electrolyte leakage (EL) and plant Pb²⁺ concentration were correlated with the reasonable growth of Pb²⁺-stressed plants and their grain yield. Results point out that, better growth and yield characteristics, MSI, RWC, leaf photosynthetic pigment and osmoprotectant concentrations, and nutrient contents were obtained with seed soaking in 0.25 mM Spm, 0.50 mM Spd or 1.0 mM Put than those generated with seed soaking in water under 2.0 mM Pb²⁺ stress. In contrast, EL and the concentration of endogenous Pb²⁺ were significantly reduced. However, the Pb²⁺-free control positively exceeded the all stressed treatments. Among all tested PAs, 1.0 mM Put showed the best results and thus is recommended, as seed soaking, for wheat to grow well under Pb²⁺ stress.     

Natural bee-honey based biostimulants confer salt tolerance in onion via modulation of the antioxidant defence system

Plant biostimulants are an emerging trend of crop management products which can enhance nutrient uptake, plant growth and productivity under various abiotic stresses. The ability of diluted bee-honey extract (DHE) to enhance the tolerance of onion plants to salinity stress has been investigated. Two-season field experiments were consecutively conducted in 2015/16 and 2016/17 to study the effect of 25–50 g/L DHE foliar application on growth, yield, physio-biochemical attributes, and antioxidative defence of two onion cultivars (i.e. Giza^Red and Giza-20) grown on a saline soil (EC = 8.81 dS m^?1). Results exhibited that DHE significantly increased biomass production, bulb yield and water use efficiency, leaf photosynthetic and pigments contents. Additionally, DHE applicati\on also improves osmoprotectants, membrane stability index (MSI) and relative water content (RWC), and enzymatic and non-enzymatic antioxidants of both onion cultivars in comparison with untreated control plants. In general, both cultivars showed a similar response to the DHE. Results of this study highlighted the potential impact of DHE as a promising plant bio-stimulant for overcoming the harmful effects of soil salinity stress by increasing the activity of plant antioxidative defence systems     

Stimulation of anthraquinone production in suspension cultures of Cassia acutifolia by salt stress.

Suspension cultures of Cassia acutifolia were established by transferring callus tissues derived from root, hypocotyl and cotyledon explants onto liquid MS-medium supplemented with 1.0 mg/l 2.4-D and 0.1 mg/l kinetin and containing increasing levels of NaCl. The stress induced by salt NaCl raised anthraquinone content and reduced growth of cultures. The levels of anthraquinones and their glycosides as sennosides showed distinct changes in cells and media as well as in the different cultures initiated from various explants. Furthermore, the salt stress tended to affect more drastically the productivity of anthraquinones in hypocotyl and cotyledon cell cultures than in root cultures.     

Effects of the application of ‘cash’ on the growth,fruit yield,and nutrient status of tomato (Solanum lycopersicum L.) grown in reclaimed saline soil

Summary

The effects of ‘cash’ [a novel 2:5:1 (w/w/w) mixture of calcium sulphate, ground sunflower heads, and humic acid] as a soil amendment on the growth, fruit yield, and leaf nutrient status of tomato (Solanum lycopersicum L.) grown on reclaimed saline soil (EC = 9.4 dS m^–1) were investigated. A glasshouse experiment was performed in a completely randomised design with six treatments (0, 10, 20, 30, 40, or 50 g ‘cash’ kg^–1 soil) each with four replicates. The results indicated that ‘cash’ increased both the shoot dry weight (DW) plant^–1 and the root DW plant^–1, the free proline contents of leaves, and leaf chlorophyll contents. The use of ‘cash’ also increased the number of fruit plant^–1, fruit yield pot^–1, and fruit vitamin C contents, although total soluble solids (TSS) contents were not affected. The contents of nitrogen (N), potassium (K), and calcium (Ca), and the Ca:Na ratios of leaf tissues increased with all application rates of ‘cash’. Leaf phosphorus (P) contents showed no response to any applied level of ‘cash’. Leaf sodium (Na) contents declined gradually with an increase in the level of ‘cash’ applied to the soil. We concluded that ‘cash’ has a pronounced positive effect on the growth and fruit yield of tomato plants grown in reclaimed saline soil. ‘Cash’ therefore has the potential to be used as a soil amendment for vegetable crops such as tomato to overcome the adverse effects of salinity in newly-reclaimed soils.     

Effect of 24-epibrassinolide on growth,yield, antioxidant system and cadmium content of bean (Phaseolus vulgaris L.) plants under salinity and cadmium stress

The plants of Phaseolus vulgaris L. were grown in the presence of NaCl and/or CdCl₂ and were sprayed with 5 μM of 24-epibrassinolide (EBL) at 15 days after transplanting (DAT) and were sampled at 30 DAT and at the end of experiment. The plants exposed to NaCl and/or CdCl₂ exhibited a significant decline in growth, the level of pigment parameters, green pod yield and pod protein. However, the follow up treatment with EBL detoxified the stress generated by NaCl and/or CdCl₂ and significantly improved the above parameters. The NaCl and/or CdCl₂ increased electrolyte leakage, lipid peroxidation and plant Cd²⁺ content, and decreased the membrane stability index (MSI) and relative water content. However, the EBL treatment in absence of the stress improved the MSI and relative water content and minimized plant Cd²⁺ content but could not influence electrolyte leakage and lipid peroxidation. The antioxidative enzymes and the level of proline exhibited a significant increase in response to EBL as well as to NaCl and/or CdCl₂ stress.     

Assessment of some barley germplasms based on RAPD analysis and anti-nutritional factors

The variation among some barley germplasm (Giza 123, Giza 127, Giza 130, Desert, and Sinai) was investigated comparatively at the molecular and biochemical levels. Leaf DNAs extracted from different barley germplasm were amplified with randomly chosen primers in a Polymerase Chain Reaction (PCR) using Random Amplified Polymorphic DNA (RAPD) technique. Only five primers amplified all DNA templates among 15 primers. Primers generated a total of 112 DNA fragments ranged from 1.2 to 0.1 kbp. Out of the 112 fragments, 16 (14.29%) were polymorphic. The result indicated that fragments generated per primer, with an average of 22.4 products, where the number of polymorphic bands per primer, with an average of 3.2 polymorphic bands. In addition, the genetic variation in the anti-nutritional factors and nutrient composition of the same genotypes were determined. A wide variation in total phenolic, phytic, tannin, vicine, and saponin contents was found among these germplasm. The range of total phenolic was 3.83 to 7.50 mg g⁻¹ d.w. Among all germplasm, Desert germplasm was characterized by the highest tannin content. However, saponin ranged between 5.66 mg g⁻¹ d.w. (in Giza 123) to 9.21 mg g⁻¹ d.w (in Sinai) germplasm. The concentrations of the phytic acid were generally low, ranging between 0.99 to 6.78 mg g⁻¹ d.w. The germplasm Desert and Sinai had the highest level of vicine, 1.89 and 1.87 mg g⁻¹ d.w., respectively. The results of the molecular characterization and anti-nutritional content can be used as the starting point needed to identify the valuable Egyptian barley germplasm.     

Improved Salinity Tolerance by Phosphorus Fertilizer in Two Phaseolus vulgaris Recombinant Inbred Lines Contrasting in Their P‐Efficiency

Legumes' sensitivity to salt is exacerbated under growth conditions requiring nitrogen fixation by the plant. Phosphorus (P) deficiency is widespread in legumes, especially common bean (Phaseolus vulgaris L). To examine the performance of P. vulgaris under salt stress conditions, a field experiment was conducted using two recombinants inbred lines (RILs) 115 (P‐deficiency tolerant) and 147 (P‐deficiency susceptible), grown under different salinity levels (L) (1.56, 4.78, and 8.83 dS m^?1 as LI, L2, and L3, respectively) and supplied with four P rates (0, 30, 60, and 90 kg ha^?1 P as P0, P30, P60, and P90, respectively) in order to assess the impact of P on salt tolerance. Results indicate that growing both RILs at P60 or P90 under all salinity levels (especially L1) significantly increased total chlorophyll, carotenoids, total soluble sugars, total free amino acids, and proline. Increasing P supply up to P60 under all salinity levels significantly induced higher accumulation of P, K⁺, Ca²⁺ and Mg²⁺ leaves in both RILs. Based on quadratic response over all locations, the maximum seed yield of 1.465 t ha^?1 could be obtained at application of P 81.0 kg ha‐1 in RIL115, while seed yield of 1.275 t ha^?1 could be obtained with P rate of 78.3 kg ha^?1 in RIL147. RIL115 exhibited more salt‐tolerance with positive consequence on plant biomass and grain yield stability. Improved salt tolerance through adequate P fertilization is likely a promising strategy to improve P. vulgaris salinity tolerance and thus productivity, a response that seems to be P‐rate dependent.