Impact of the foliar application of nanoparticles, sulfate and iron chelate on the growth, yield and nitrogen assimilation in green beans

Nano-fertilizers (Nfs) have the potential to revolutionize agricultural systems through nanostructures ranging from 1 to 100 nm that address environmental responses and a more targeted biological demand. The purpose of this work was to study the impact of the foliar application of nanoparticles (NPs), sulfate and iron chelate on the growth, yield and assimilation of nitrogen in green beans. The iron was applied foliar in three different ways: Iron oxide nanoparticles (Fe2O3), ferric sulfate (Fe2(SO4)3) and iron chelate (Fe-EDDHA) in doses of 0, 25, 50, 100 and 200 ppm. The treatments that produced a higher total biomass increase were NPs and Fe-EDDHA at 50 ppm, with increases of 37% and 47% respectively compared to the control (with no application of Fe). Regarding the in vivo nitrate reductase activity, significant differences were obtained, particularly in the NPs and Fe-EDDHA treatment, with increases of 71% and 72% respectively. NPs at low doses favored maximum fruit production with increases of 88% in comparison to the control. Finally, it is concluded that the optimal doses that enhanced total biomass, production and assimilation of nitrogen were Fe2(SO4)3 at 25 ppm, Fe-EDDHA at 100 ppm and Fe2O3 at 25 ppm. The efficiency of foliar absorption of iron was found in treatments with Fe2O3 at 50 and 100 ppm. The foliar absorption efficiency of NPs offers sustainable alternatives to increase the productivity of the green bean.

USE HERBAL PLANTS (CHAMAENERION ANGUSTIFOLIUM AND TANACETUM VULGARE) FOR MONITORING OF TERRITORIES POLLUTED BY FLUORINE-CONTAINING EMISSIONS

Specific features of fluoride accumulation by two species of herbaceous plants – Chamerion angustifolium (L.) Holub and Tanacetum vulgare L., were found at different distances from the aluminum smelter located in the Baikal region. The highest fluorine content was recorded at the distance of 3 km from the smelter: 433 mg / kg of dry weight in C. angustifolium, 306 mg / kg in T. vulgare. According to the level of accumulation of fluorine, the organs of C. angustifolium were arranged in the following order (as the concentration decreases): leaves> roots> stems ≥ flowers, for T. vulgare the another sequence was typical: roots> leaves> flowers ≥ stems. Calculation of the root barrier coefficient for different organs of C. angustifolium and T. vulgare indicates the existence of barrier mechanisms that prevent the entry of fluorine from the soil into the aerial part of plants. A feature of the accumulation of fluoride in the leaves of C. angustifolium is its active foliar absorption and barrier-free intake from the soil. It has been established that the rate of fluoride accumulation by the reproductive organs of both species is much lower than by the assimilation organs. The data obtained make it possible to recommend using C. angustifolium for monitoring air fluorine pollution, and T. vulgare – for soil fluorine pollution.

Impact of fog drip versus fog immersion on the physiology of Bishop pine saplings

Fog-drip to the soil is the most obvious contribution of fog to the water budget of an ecosystem, but several studies provide convincing evidence that foliar absorption of fog water through leaf wetting events is also possible. The focus of our research was to assess the relative importance of fog drip and fog immersion (foliar wetting) on leaf gas-exchange rates and photosynthetic capacity of a coastal pine species, Bishop pine (Pinus muricata D.Don), a drought-sensitive species restricted to the fog belt of coastal California and offshore islands. In a controlled experiment, we manipulated fog water inputs to potted Bishop pine saplings during a 3 week dry-down period. Ten saplings were randomly assigned one of two fog treatments: (1) fog drip to the soil and canopy fog immersion, or (2) fog immersion alone. Five saplings were assigned the ‘control’ group and received no fog water inputs. We found that fog immersion alone significantly increased carbon assimilation rates and photosynthetic capacity of saplings as soil moisture declined compared with those that received no fog at all. The highest carbon assimilation rates were observed in saplings that also received fog drip. Soil moisture was 40% higher in the fog immersion compared with the control group during the dry-down, indicating a reduced demand for soil water in saplings that had only leaves wetted by canopy interception of fog. Leaf-level physiology is more strongly enhanced by fog drip compared with fog immersion, although the results of this study provide evidence that foliar absorption is a viable mechanism by which Bishop pines use fog water and that it can enhance instantaneous plant carbon gain and potentially whole plant productivity.