A comparative study of Zn and Fe distribution in two contrasting wheat genotypes

Effect of zinc and iron interaction on their distribution was examined in two wheat genotypes (UP262 and UP2628) under foliar application of 0, 0.25 and 0.50% ZnSO4 solution tagged with 925 KBq of Zn65 pot-1 for Zn and 0, 0.5 and 1.0% FeSO4 solution tagged with 925 KBq of Fe59 pot-1 for Fe at 30, 60 and 90 days after planting. Maximum grain yield of UP2628 (2.7 g pot-1 ) was recorded at 0.5%ZnSO4+0%FeSO4 while that of UP262 (2.63 g pot-1 ) was recorded at 0.5%ZnSO4+1.0%FeSO4. The highest straw yield of UP2628 (2.75 g pot-1 ) was noted at 0.5% ZnSO4+1.0%FeSO4 while that of UP262 (2.91 g pot-1 ) with 0.5%ZnSO4+0.5%FeSO4. Application of 0.5% and 1.0% FeSO4 reduced the accumulation of 65Zn in all parts of both the varieties. Regarding the 59Fe accumulation, it was found to be decreased with the increased application of ZnSO4 solution from 0.25% and 0.5% as compared to without application of Zn. On comparing translocation efficiencies of both the varieties, UP2628 showed better translocation thus accumulated higher zinc and iron. Therefore, variety UP2628 can be used further for crop improvement programme

The Biosynthesis, Mechanism of Action, and Physiological Functions of Melatonin in Horticultural Plants: A Review

Melatonin, a hormone known for its role in regulating sleep–wake cycles in mammals, has been found to have diverse functions in horticultural plants. In recent years, research has revealed the involvement of melatonin in various physiological processes in plants, like regulation of growth and development, stress tolerance, and antioxidant defense. Melatonin can augment seed germination, roots, shoot growth, and biomass accumulation in horticultural crops. It also performs a vital role in regulating vegetative and reproductive growth stages, floral transition, and leaf senescence. Melatonin improves stress tolerance in crops by regulating root architecture, nutrient uptake, and ion transport. Additionally, melatonin works like a broad-spectrum antioxidant by scavenging reactive oxygen species and enhancing antioxidant activity. The mechanism of action of melatonin in horticultural plants involves gene expressions, hormone signaling pathways, and antioxidant defense pathways. Melatonin also interacts with other plant growth regulators (PGRs), comprising auxins, cytokinins, and abscisic acid to coordinate various physiological processes in plants. Melatonin has evolved as a versatile chemical entity with diverse functions in horticultural plants, and its potential applications in crop production and stress management are increasingly being explored. This review aims to provide a comprehensive insight into the present state of knowledge about melatonin and its role in horticulturally important plants and identify avenues for further research and practical applications. Further study must be conducted to fully elucidate the mechanisms of melatonin action in crops and to outline effective strategies for its practical use in horticultural practices