The impact of enhanced atmospheric carbon dioxide on yield, proximate composition, elemental concentration, fatty acid and vitamin C contents of tomato (Lycopersicon esculentum)

The global average temperature has witnessed a steady increase during the second half of the twentieth century and the trend is continuing. Carbon dioxide, a major green house gas is piling up in the atmosphere and besides causing global warming, is expected to alter the physico-chemical composition of plants. The objective of this work was to evaluate the hypothesis that increased CO₂ in the air is causing undesirable changes in the nutritional composition of tomato fruits. Two varieties of tomato (Lycopersicon esculentum) were grown in ambient (400 μmol mol^?1) and elevated (1,000 μmol mol^?1) concentration of CO₂ under controlled conditions. The fruits were harvested at premature and fully matured stages and analyzed for yield, proximate composition, elemental concentration, fatty acid, and vitamin C contents. The amount of carbohydrates increased significantly under the enhanced CO₂ conditions. The amount of crude protein and vitamin C, two important nutritional parameters, decreased substantially. Fatty acid content showed a mild decrease with a slight increase in crude fiber. Understandably, the effect of enhanced atmospheric CO₂ was more pronounced at the fully matured stage. Mineral contents of the fruit samples changed in an irregular fashion. Tomato fruit has been traditionally a source of vitamin C, under the experimental conditions, a negative impact of enhanced CO₂ on this source of vitamin C was observed. The nutritional quality of both varieties of tomato has altered under the CO₂ enriched atmosphere.     

Effect of chromium on growth attributes in sunflower (Helianthus annuus L.)

Heavy metal soil pollution takes place when the metal concentration of soil exceeds natural background level and causes ecological destruction and deterioration of the environment.In the present study,a pot experiment was conducted to evaluate the effect of chromium-contaminated soil in sunflower(Helianthus annuus L.)growth attributes.Three different levels of chromium(Cr)i.e.,20, 40,and 60 mg/kg were applied to three varieties of sunflower(G-3,G-9,and G-59).The results of morphological,chemical,and yield p...     

Effect of chromium on growth attributes in sunflower (Helianthus annuus L.)

Heavy metal soil pollution takes place when the metal concentration of soil exceeds natural background level and causes ecological destruction and deterioration of the environment. In the present study, a pot experiment was conducted to evaluate the effect of chromium-contaminated soil in sunflower (Helianthus annuus L.) growth attributes. Three different levels of chromium (Cr) i.e., 20, 40, and 60 mg/kg were applied to three varieties of sunflower (G-3, G-9, and G-59). The results of morphological, chemical, and yield parameters were recorded at crop maturity. The result showed that germination, root, and shoot lengths were decreased with increase in Cr concentrations. A gradual decrease was observed for various morphological parameters like root fresh and dry weights, shoot fresh and dry weights, and plant height with increase in Cr levels. A comparison among Cr treatments obtained a significant decrease in yield parameters as achenes/capitulum, achenes/plant, and 100 achenes weight in three varieties. Cr was significantly absorbed by roots but its transport to other parts of plants was slow, and uptake in seeds was much lower than in roots and shoots.