Plateau plants develop unique features adapting to the alpine environment

Effects of appropriate low-temperature treatment on the yield and quality of pigmented potato (Solanum tuberosum L.) tubers

Temperature is one of the important environmental factors affecting plant growth, yield and quality. Moreover, appropriately low temperature is also beneficial for tuber coloration. The red potato variety Jianchuanhong, whose tuber color is susceptible to temperature, and the purple potato variety Huaxinyangyu, whose tuber color is stable, were used as experimental materials and subjected to 20 °C (control check), 15 °C and 10 °C treatments during the whole growth period. The effects of temperature treatment on the phenotype, the expression levels of structural genes related to anthocyanins and the correlations of each indicator were analyzed. The results showed that treatment at 10 °C significantly inhibited the potato plant height, and the chlorophyll content and photosynthetic parameters in the leaves were reduced, and the enzyme activities of SOD and POD were significantly increased, all indicating that the leaves were damaged. Treatment at 10 °C also affected the tuberization of Huaxinyangyu and reduced the tuberization and coloring of Jianchuanhong, while treatment at 15 °C significantly increased the stem diameter, root-to-shoot ratio, yield and content of secondary metabolites, especially anthocyanins. Similarly, the expression of structural genes were enhanced in two pigmented potatoes under low-temperature treatment conditions. In short, proper low temperature can not only increase yield but also enhance secondary metabolites production. Previous studies have not focused on the effects of appropriate low-temperature treatment during the whole growth period of potato on the changes in metabolites during tuber growth and development, these results can provide a theoretical basis and technical guidance for the selection of pigmented potatoes with better nutritional quality planting environment and the formulation of cultivation measures.

Effects of Hypoxemia by Acute High-Altitude Exposure on Human Intestinal Flora and Metabolism

This study examined the effects of hypoxemia caused by acute high-altitude hypoxia (AHAH) exposure on the human intestinal flora and its metabolites. The changes in the intestinal flora, metabolism, and erythropoietin content in the AHAH population under altitude hypoxia conditions were comprehensively analyzed using 16S rRNA sequencing, metabonomics, and erythropoietin content. The results showed that compared with those in the control group (C group), the flora and metabolites in the hypoxemia group (D group) were altered. We found alterations in the flora according to the metabolic marker tyrosine through random forest and ROC analyses. Fecal and serum metabonomics analyses revealed that microbial metabolites could be absorbed into the blood and participate in human metabolism. Finally, a significant correlation between tyrosine and erythropoietin (EPO) content was found, which shows that human intestinal flora and its metabolites can help to confront altitude stress by regulating EPO levels. Our findings provide new insights into the adaptive mechanism and prevention of AHAH.

Different doses of UV-B radiation affect pigmented potatoes' growth and quality during the whole growth period

INTRODUCTION

UltraViolet- Biological (UV-B) plays an important role in plant growth and the formation of nutrients, especially secondary metabolites.

METHODS

To investigate the phenotypic changes, physiological responses, and internal genes expression of potatoes under enhanced UV-B radiation, two Yunnan native pigmented potatoes varieties named "Huaxinyangyu" and "Jianchuanhong" were exposed to different UV-B doses during whole growth duration.

RESULTS

Pearson correlation analysis and principal component analysis showed that the agronomic characters (i.e. plant height, pitch, stem diameter, and root shoot ratio) of plants treated with low dose ultraviolet (T1) did not change significantly compared with the absence of ultraviolet radiation (CK), even unit yield increased slightly; Similarly, under low UV-B radiation, photosynthetic and physiological parameters (photosynthetic rate, stomatal conductance, respiration rate, and transpiration rate) of leaves were significantly increased. In addition, low-dose UV-B treatment promoted the synthesis of tuber nutrients (e.g. phenols, chlorogenic acids, flavonoids, vitamin C, anthocyanins) and increased the expression of structural genes for anthocyanin synthesis. The number of nutrients and gene expression in tubers raised by the "Huaxinyangyu" was the highest at 84 days, and "Jianchuanhong" was the highest at 72 days. However, the higher dose of UV-B radiation (T2) will cause greater damage to the pigmented potatoes plants, making the plants reduce the yield, and significantly reduce the tuber nutrients.

DISCUSSION

This study showed that proper ultraviolet radiation will not harm pigmented potatoes, but also improve their oxidative stress tolerance, increase the structure genes expression of anthocyanins and continuously synthesize beneficial substances to improve the yield and quality of potato tubers.