A relationship between the antioxidant defence system and salt tolerance in two clones of potato (Solanum tuberosum L.) differing in salt sensitivity was studied. The antioxidant defence system of the sensitive clone responded differently to 100 and 150 mM NaCl. At 100 mM NaCl, growth, dehydroascorbate reductase and catalase activities remained unaltered, but chlorophyll and reduced glutathione content decreased (23% and 35%, respectively), while ascorbate content and superoxide dismutase activity were increased 34% and 63%, with respect to the control (0 mM NaCl). The superoxide dismutase increment was higher under 150 mM NaCl treatment, while a general decrease (except for dehydroascorbate reductase and catalase activities) in all the antioxidant parameters studied was observed in the sensitive clone. Reduced glutathione and ascorbate, the main antioxidant soluble defences, and all antioxidant enzymes (except catalase) were significantly elevated in the tolerant clone compared to the sensitive one when both were grown in the absence of NaCl. Under 100 and 150 mM NaCl treatments, no changes in the antioxidant stress parameters were detected in the tolerant clone. These results suggest a relationship between salt tolerance and the antioxidant defence system in the two clones.

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We have established two transgenic cell suspension culture lines of Nicotiana tabacum that express the catalytic antibody 14D9 as a secretory product (sec-Ab) or as a KDEL-tagged product in the endoplasmic reticulum (Ab-KDEL), respectively. After 3 years of culture, the performance improved to a production level of 0.15 ± 0.03 lg ml -1 on the seventh day of culture for the sec-Ab line and 0.48 ± 0.05 lg ml -1 on the third day for Ab-KDEL line. Analysis of the effect of osmotic stress using mannitol (90 g l -1 ) as an osmolite revealed that there was a 12-fold increase in antibody yield (1.96 ± 0.20 lg ml -1 ) on the seventh day of culture in line sec-Ab and a fivefold increase (2.31 ± 0.18 lg ml -1 ) on the seventh day for line Ab-KDEL. The concentration of the antibody in the culture medium was not significant. Dimethyl sulfoxide used as a permeabilizing agent was not effective in increasing 14D9 yield, but it did cause distinctive cell damage at all concentrations tested.

The COVID-19 pandemic has had a deep impact on the way we perceive our world. This study explores its effect on Urban Green Space (UGS) perception in Buenos Aires City (CABA), Argentina. We provide a detailed overview of the distribution of UGS in CABA, along with socio-economic analysis and visitors' profile and perception before and during the restrictive measures adopted by the national authorities to contain the COVID-19 outbreak (July to December of 2020). We conducted a series of surveys based on open and closed questions. Before the pandemic, surveys were carried out in situ in eight parks of six districts, randomly chosen. During the confinement, online surveys were conducted. According to our results, the mean UGS density in CABA is 6.09 m 2 /person, but marked differences between districts exist, ranging from 0.02 m 2 /person to 17.68 m 2 /person. This uneven distribution causes differences in the quality of life of CABA inhabitants, perhaps more pronounced during reduced-mobility situations like COVID-19 confinement. Socio economic analysis were done linking multidimensional poverty, COVID-19 positive cases and urban mobility in CABA. Regarding UGS visitors, before the confinement, the majority of respondents were employees or students; during the confinement, employees and retirees predominated. When asked to choose important attributes to describe their perception about the UGS from a given list, respondents selected “calm,” “green,” and “sounds of nature,” without differences before and during the confinement. However, when asked about the UGS role, the main answer was “a place to be with nature” before the confinement and “an important place in the city” during it. Understanding how society perceives the UGS, especially during crises, is essential to rethink the urban landscape and prepare our cities, towards biophilic cities and for a more sustainable future.