Drought is one of the major abiotic stresses that drastically reduces crop yield throughout the world. Being precursor of glutathione biosynthesis and involvement in other metabolic processes, cysteine (Cys) has been shown to alter growth and development in plants. In this context, we investigated Cys-induced physicochemical alterations in oat (Avena sativa L. var. Scott and var. F-411) plants under drought stress.
There were two levels of drought stress, i.e., control (100% field capacity) and drought (50% field capacity) and three levels of foliar application of Cys, i.e., 0, 10, and 20 mM. Experimental design was completely randomized block design.
Drought stress significantly decreased growth parameters, chlorophyll (Chl) contents, while increased leaf membrane permeability (MP), ascorbic acid (AsA), and activity of catalase (CAT) and peroxidase (POD) enzymes. Foliar application of varying Cys levels significantly increased root fresh weight, root length, photosynthetic pigments (chl. a and b), AsA contents in var. Scott, and shoot length, total free amino acids, total phenolics and free proline contents in var. F-411.
Of the two oat varieties, var. Scott proved better in root fresh weight, root length, chl. a and b contents, and total phenolic contents, while var. F-411 was higher in the values of shoot length, MP (%), total free amino acids, and free proline contents. Thus, on the basis of strong root system, total phenolics, and more photosynthetic contents (chl. a and b contents), var. Scott could be grown under semi-arid environments than that of var. F-411.
A tetradentate set of N2O2 salicylaldehyde-amine-N-dione Schiff base was prepared by condensation with salicylaldehyde, ethylenediamine, 2,4-dione and
reduction with NaBH4. The ligand system was characterized by 1H-NMR and FT-IR spectroscopy and HPLC. Radiolabeling studies of the 99mTc-complex were performed using stannous ions as the reducing agent. The purity of the complex was determined by ascending
solvent system on paper chromatography and instant thin-layer chromatography (ITLC). The yield of the complex was >90%. Biodistribution
of the 99mTc-complex of the precursor was studied in rabbits. A significant uptake and retention of injected activity was observed in
the liver and cleared through the bladder. A faint activity was also observed in kidneys. These results indicate that the
proposed system may be suitable for development of a liver/spleen imaging agent for future clinical applications.