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Global veganism campaigns like 'Veganuary' have gained popularity. We conducted an observational study to assess the impact of a 4-week vegan diet during 'Veganuary' on nutrient intake, status, knowledge, and motivations for veganism. Data were collected before and after 'Veganuary', using Food Frequency Questionnaires (FFQs) to estimate dietary intake. Micronutrient knowledge and motivation were assessed through questionnaires. A total of 154 UK adults aged 18–60 years (2019: n81; 2020: n73) participated. Groups were vegetarians and omnivores committed to a 4-week vegan diet during 'Veganuary'. Control groups were vegans and omnivores who did not transition. Short-term vegan diets significantly decreased intake of iodine, B12, cholesterol, and saturated fatty acids (SFAs) in omnivores. Micronutrient knowledge was low, and motivation for veganism varied. Short-term vegan diets reduce macro- and micronutrient intake in omnivores. Veganuary participants could benefit from nutritional guidance or supplementation. Attention is required for UK micronutrient intake and knowledge. Motivations for vegan pledges may influence diets, warranting further research. [ABSTRACT FROM AUTHOR]

The hyperaccumulator Thlaspi caerulescens was grown with Hordeum vulgare and Lepidium heterophyllum in a split pot experiment to examine the effect of rhizosphere interactions on metal uptake.The objective was to assess the viability of such intercropping as either (1)a system of 'phytoprotection 'for nonaccumulating plants or (2)a means of enhancing phytoextraction with large-biomass crops through increased metal mobilization within the shared rhizosphere.The plants were sepa- rated by (1)an impermeable barrier,(2)a permeable root barrier,or (3)no physical barrier to allow different degrees of root interaction.Studies of rhizosphere effects using split pot experiments are subject to considerable uncertainty by the need to relate test results to appropriate control plants.This was resolved by comparing plant metal concentrations to 'equivalent 'control plants,with the same yield,based on the observed variation in metal concentration with yield under similar growing condi- tions. Cadmium concentration in H.vulgare was increased by a factor of 2.4 when it was grown alongside T.caerulescens without a barrier.In contrast,the uptake of zinc by H.vulgare was significantly decreased,probably through metal depletion within the zone of the Zn-hyperaccumulator 's rhizosphere. T.caerulescens also apparently increased the concentration of Cd in H.vulgare by a factor of 1.4 when the roots of the two plants were separated by a permeable barrier that allowed movement of soil solution but... [ABSTRACT FROM AUTHOR]

Potato plants (Solanum tuberosum L. cv. Bintje) were grown in open‐top chambers (OTCs) under three CO2 levels (ambient and 24 h d−1 seasonal mean concentrations of 550 and 680 μmol mol−1) and two O3 levels (ambient and a seasonal mean 8 h d−1 concentration of 50 nmol mol−1). The objectives were to determine the effects of season‐long exposure to these key climate change gases on gas exchange, leaf thickness and epidermal characteristics. The experimental design also provided an ideal opportunity to examine within‐leaf variation in epidermal characteristics at the whole‐leaf level. Stomatal and epidermal cell density and stomatal index were measured at specific locations on the youngest fully expanded leaf (centre of lamina, mid‐way between tip and base) and representative whole leaves from each treatment. Effects on leaf conductance, assimilation rate and instantaneous transpiration efficiency were determined by infrared gas analysis, while anatomical characteristics were examined using a combination of leaf impressions and thin sections. Exposure to elevated CO2 or O3 generally increased leaf thickness, leaf area, stomatal density, and assimilation rate, but reduced leaf conductance. The irregular stomatal distribution within leaves resulted from a combination of uneven differentiation and expansion of the epidermal cells. The results are discussed with reference to sampling protocols and the need to account for within‐leaf variation when examining the impact of climate change or other environmental factors on epidermal characteristics. [ABSTRACT FROM PUBLISHER]

This study examined the impact of season-long exposure to elevated carbon dioxide (CO2 ) and ozone (O3 ), individually and in combination, on leaf chlorophyll content and gas exchange characteristics in potato (Solanum tuberosum L. cv. Bintje). Plants grown in open-top chambers were exposed to three CO2 (ambient, 550 and 680 µmol mol-1 ) and two O3 treatments (ambient and elevated; 25 and 65 nmol mol-1, 8 h day-1 means, respectively) between crop emergence and maturity; plants were also grown in unchambered field plots. Non-destructive measurements of chlorophyll content and visible foliar injury were made for all treatments at 2-week intervals between 43 and 95 days after emergence. Gas exchange measurements were made for all except the intermediate 550 µmol mol-1 CO2 treatment. Season-long exposure to elevated O3 under ambient CO2 reduced chlorophyll content and induced extensive visible foliar damage, but had little effect on net assimilation rate or stomatal conductance. Elevated CO2 had no significant effect on chlorophyll content, but greatly reduced the damaging impact of O3 on chlorophyll content and visible foliar damage. Light-saturated assimilation rates for leaves grown under elevated CO2 were consistently lower when measured under either elevated or ambient CO2 than in equivalent leaves grown under ambient CO2. Analysis of CO2 response curves revealed that CO2-saturated assimilation rate, maximum rates of carboxylation and electron transport and respiration decreased with time. CO2-saturated assimilation rate was reduced by elevated O3 during the early stages of the season, while respiration was significantly greater under elevated CO2 as the crop approached maturity. The physiological origins of these responses and their implications for the performance of potato in a changing climate are discussed. [ABSTRACT FROM AUTHOR]

Investigates the effect of elevated carbon dioxide concentration on growth and yield of potatoes. Increase in biomass and yield; Absence of effects due to elevated ozone concentration on growth; Detection of carbon dioxide and ozone interactions in senescent leaf number and green leaf ratio.