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Peanut has a fairly strong ability of accumulating cadmium (Cd) from the soil, and the problem of Cd content in peanut exceeding the food safety standard is serious in some regions of China. Seed coating is a common technology to control diseases and insect pests and enhance stress resistance in peanut production, but the research of using seed coating technology to control Cd pollution risk in peanut producing areas has not been reported. This study first screened out three suitable concentrations of manganese (Mn) and zinc (Zn) coating agents by seed germination test, and then further screened out the concentration of coating agent with the best Cd reduction effect by pot experiment. The effect of Mn fertilizer and Zn fertilizer seed coating on Cd transfer within peanut plant in Cd-contaminated soil was further explored through pot experiment. The results of seed germination test showed that the seed coating treatment with low to moderate concentrations of Mn and Zn fertilizer did not affect the seed germination rate and could promote the root length, while the excessive concentration could obviously inhibit the seed germination. The results of pot experiment showed that among the seed coating agents of Mn and Zn, 3% Mn fertilizer coating agent (Mn3) and 2% Zn fertilizer coating agent (Zn2) had the most significant effect on reducing Cd in peanut seeds, with the Cd reduction rates reaching 19.0% and 24.1% respectively, and Zn2 had the better Cd reduction effect. Compared with the control, the Cd bioaccumulation factor of roots in the two treatments decreased significantly, the Cd translocation factor (TF) from roots to shoots increased significantly, the TF from shoots to seeds decreased, while the TF from roots to seeds had no obvious change. Compared with the control, the absorption of Cd in peanut plants under Mn3 and Zn2 treatments decreased by 9.18% and 13.6%. There was a significant negative correlation between the contents of Cd in peanut seeds and roots and the contents of Mn and Zn in roots. Seed coating with Mn and Zn can reduce the Cd content in peanut seeds by inhibiting the absorption of Cd by roots and the transport of Cd within peanut plant. This study put forward the technology of reducing Cd content in peanut by seed coating, which provided a new method for risk control of Cd pollution in peanut producing areas. Key words: seed coating; seed germination; peanut; cadmium ble sugar decreased after PS-NPs exposure. Transcriptome analysis showed that a total of 2112 differentially expressed genes were generated by PS-NPs exposure treatment, GO and KEGG analysis showed that they were mainly enriched in pathways related to redox reaction, reaction to ethylene and abscisic acid, amino acid metabolism and synthesis of other secondary metabolites. It was noted that 250 transcription factors were differentially expressed, mainly including the ERF, WRKY, NAC, bHLH and MYB transcription factor families. This experiment lays a foundation for further exploring the impact of nanoplastics on crops such as soybeans and its molecular mechanism. [ABSTRACT FROM AUTHOR]

[Objective] This study explored the differences in heat resistance of different varieties of Helleborus orientlis under high temperature stress and screened the varieties suitable for garden application in summer high temperature areas of China to improve the cultivation of new varieties with heat resistance. [Method] Nine varieties of Helleborus orientlis were selected to observe symptoms of heat injury, detect effects on physiological indexes and study high temperature tolerance through artificial simulation of high temperature stress. Combined with membership function analysis, the heat resistance was evaluated comprehensively. [Result] Under high temperature stress, Single white and Single white pink vein had no obvious symptoms of heat injury. Contents of total chlorophyll (Chi (a + b)), chlorophyll a (Chi a), chlorophyll b (Chi b) and carotenoid (Caro) as well as relative water content (REC) of all cultivars decreased. Relative conductivity (RWC), hydrogen peroxide (H2O2) content, and superoxide dismutase (SOD) and peroxidase (POD) activities increased, while malondialdehyde (MDA) content, proline (Pro) content and catalase (CAT) activity varied differently among varieties. According to the subordination function analysis, the heat resistance of studied varieties was in the order of Single white > Anemone white spotted > Single white pinkvein>Anemone white>Double white spotted > Anemone red>Double red>Double white>Double green spotted. [Conclusion] Single white had the strongest heat resistance among the nine Helleborus orientlis varieties and it is most suitable for planting in gardens in areas with high temperature in summer. [ABSTRACT FROM AUTHOR]

As a shade plant with high ornamental value, Saxifraga stolonifera is often used in landscape of courtyards and gardens. The light intensity may have an important infuence on its growth performance, especially on leaf color, formation and coloration of leaf variegation, which subsequently affects its ornamental value. However, the related study has not been reported before. In order to explore the adaptability of different cultivars of S. stolonifera to light intensity and understand their light or shade tolerance, three internationally-registered cultivars raised in China were used as the experimental materials, the effects of five light intensity treatments(100%, 85%, 60%, 40% and 15%)on plant growth and development and photosynthetic physiological indexes were investigated. The suitable indexes of light intensity for S. stolonifera were screened by the principal component analysis, and the light tolerance of the cultivars was evaluated by membership function analysis. The results were as follows:(1)The number of blades, leaf length, leaf width, leaf area, specific leaf area, chlorophyll a, chlorophyll b and total chlorophyll contents increased with shading.(2)The number of stolons, fresh weight above ground, dry weight above ground, stolon diameter, and the contents of carotenoid and flavonoids increased first and then decreased.(3)The maximum fluorescence value and the contents of soluble sugar, soluble protein and malondialdehyde of the leaves decreased with shading.(4)By analysis of principal component and membership function, the significant differences were found in the adaptability of the three cultivars to light intensity, ‘Xue Wen' > ‘Tianmu Enci' > ‘Hei Kui'. In which, 40% light intensity was optimal for ‘Xue Wen', and 15%-40% light intensities were optimal for ‘Tianmu Enci' and ‘Hei Kui'. Therefore, in horticultural practice, the suitable light intensity should be considered according to the cultivars of Saxifraga. [ABSTRACT FROM AUTHOR]

To accelerate the exploitation and use of marginal soils and develop salt-tolerant forage germplasm suitable for the coastal regions of China, seven lines of decaploid tall wheatgrass [ Thinopyrum ponticum (Podp.) Barkworth and D. R. Dewey, 2 n = 10 x = 70] were transplanted under low (.3%) and high (.5%) salt conditions for a comprehensive analysis at the adult-plant stage. Differences were observed among these materials, especially in terms of grass yield, agronomic characteristics, and physiological and biochemical indices. Line C2 grew best with the highest shoot total fresh and dry weights under all conditions except for the milk-ripe stage in Dongying in 2019. The total membership value of C2 also reflected its excellent performance after transplanting. As superior germplasm, its relatively high antioxidant enzyme activities and chlorophyll a / b ratio suggested C2 may maintain normal metabolic and physiological functions under saline conditions. Furthermore, decaploid tall wheatgrass as a forage grass species has a high nutritive value beneficial for animal husbandry. Accordingly, line C2 may be used as excellent germplasm to develop salt-tolerant cultivars in the Circum-Bohai sea. [ABSTRACT FROM AUTHOR]

Cold damage has negatively impacted the yield, growth and quality of the edible cooking oil in Northern China and Brassica napus L.(rapeseed) planting areas decreased because of cold damage. In the present study we analyzed two Brassica napus cultivars of 16NTS309 (highly resistant to cold damage) and Tianyou2238 (cold sensitive) from Gansu Province, China using physiological, biochemical and cytological methods to investigate the plant's response to cold stress. The results showed that cold stress caused seedling dehydration, and the contents of malondialdehyde (MDA), relative electrolyte leakage and O2− and H2O2 were increased in Tianyou2238 than 16NTS309 under cold stress at 4°C for 48 h, as well as the proline, soluble protein and soluble sugars markedly accumulated, and antioxidant enzymes of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) were higher in 16NTS309 compared with in Tianyou2238, which play key roles in prevention of cell damage. After exposure to cold stress, the accumulation of the blue formazan precipitate and reddish brown precipitate indicated that O2− and H2O2, respectively, were produced in the root, stem, and leaf were higher than under non-cold conditions. Contents of O2− and H2O2 in cultivar Tianyou2238 were higher than 16NTS309, this is consistent with the phenotypic result. To understand the specific distribution of O2− in the sub-cellular, we found that in both cultivars O2− signals were distributed mainly in cambium tissue, meristematic cells, mesophyll cytoplasm, and surrounding the cell walls of root, stem, leaves, and leaf vein by morphoanatomical analysis, but the quantities varied. Cold stress also triggered obvious ultrastructural alterations in leaf mesophyll of Tianyou2238 including the damage of membrane system, destruction of chloroplast and swelling of mitochondria. This study are useful to provide new insights about the physiological and biochemical mechanisms and cytology associated with the response of B. napus to cold stress for use in breeding cold-resistant varieties. [ABSTRACT FROM AUTHOR]

Tree peony (Paeonia section Moutan DC.) is an excellent ornamental plant, of which Paeonia ostii (P. ostii) has a high oil value. It is widely cultivated in China, but severe drought affects its growth. In this study, the effects of exogenous calcium on drought-induced damage of P. ostii were studied. The results showed that under drought stress, leaf water content showed a downward trend, while reactive oxygen species (ROS), relative electrical conductivity (REC), proline (Pro) content, and related antioxidant enzymes increased significantly. Spraying CaCl2 could effectively slow leaf wilting and water loss, induced an increase in enzyme activity of the antioxidant enzyme system, and reduced the accumulation of ROS caused by drought stress. Simultaneously, REC and Pro content could be alleviated, and the degree of cell membrane damage could be reduced. In addition, CaCl2 improved photosynthetic characteristics and chlorophyll fluorescence parameters. These results indicated that CaCl2 reduced the harmful effects of drought stress on the growth of P. ostii by regulating infiltration, activating photosynthesis, and enhancing the antioxidant system. These findings suggested that CaCl2 can be used to manage drought stress in P. ostii cultivation. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the heat stress and heat tolerance of 148 male volunteers were examined under different climatic conditions in a stainless steel climatic chamber. The conditions were 30 to 42° dry bulb temperature and 40 to 80 percent relative humidity. The subjects, aged from 19 to 26 years old, performed various activities at the metabolic heat of 175, 349 and 580W, respectively. The exposure durations and resulting heat stress were determined by measuring oral temperature, skin temperature, heart rates, blood pressure and sweating responses. The study proposed physiological limit values at exposure limits. Moreover, the study suggested that physiological measures from the experiments should be applied to evaluate the classification of extreme heat working environments in China. [Copyright &y& Elsevier]

Based on the analysis of the three-year (2000-2002) monitoring data of the four times intermittent stream water conveyance to the lower reaches of Tarim River where the stream flow was dried up for more than 30 years and the measurement of PRO, SOD and POD in plants collected from 24 vegetation plots, it is concluded that the stream water conveyance plays an important role in lifting groundwater level. The groundwater nearby the watercourse was raised from 5 ∼ 8 m in depth before the stream water conveyance to 2.5 ∼ 5 m after stream water conveyance. The physiological response of Phragmites communis, Tamarix spp. and Populus euphratica to the change of groundwater is sensitive and represents a grads change obviously. The growth of the plants in the lower reaches of Tarim River is stressed by drought to various degrees. Lengthways, the drought stress exposed to the plants increases with groundwater depth from the upper sections to the lower sections; and breadthwise, the drought stress exposed to the plants is increased with the increase of distance away from the river channel of stream intermittent water releases and of the groundwater depth. Combining the field investigation and the analysis of the plots, it is considered that the stress groundwater depths for the Phragmites communis, Tamarix spp. and Populus euphratica are 3.5 m, 5 m and 4.5 m respectively. [ABSTRACT FROM AUTHOR]

• Extreme thermal environments harm the health of outdoor workers and reduce productivity. • A field survey were conducted at four construction sites for analyzing the workers' thermal response. • Near 40 % of workers had some uncomfortable symptoms. • The effects of physiological indicators and cognitive ability on the physical and mental state of workers were significant. Extreme thermal environments harm the health and reduce the productivity of outdoor workers. Variations in human physiological indices and the thermal exposure time limit are the main factors in evaluating heat safety in an extreme thermal environment. Therefore, it is necessary to determine the relationships between human physiological indices, psychological responses, and thermal parameters to accurately predict and evaluate human thermal safety in extreme thermal environments. A field survey, including thermal parameter measurements, was conducted at construction sites in South China during the summer of 2019. The relationship between health risk and thermal parameters was obtained, and the adaptability and sensitivity of workers to i) thermal parameters (outdoor ambient temperature (T a), mean radiant temperature (T mrt), wind speed (V a), and relative humidity (RH)) and ii) physiological indicators (heart rate (HR) and auditory canal temperature (ACT)), as well as the variations in their cognitive ability, were analyzed. The results indicate that 40 % of workers experienced discomfort and that when T a > 34 °C, the working intensity of workers needs to be reduced in construction sites. The HR and ACT increased with increasing working hours, and the thermal parameters and cognitive ability decreased. To avoid discomfort, it is suggested that the HR may be kept near 94 beats/min. The effects of physiological indicators and cognitive ability on the physical and mental state of the workers were significant; with an increase in thermal environment parameters, the efficiency decreased by approximately 8%. The results of this investigation are beneficial for ensuring the occupational safety of workers and reducing the risk of heat exposure. [ABSTRACT FROM AUTHOR]