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Abstract The taproot of Glycyrrhiza uralensis is globally appreciated for its medicinal and commercial value and is one of the most popular medicinal plants. With the decline of wild G. uralensis resources, cultivated G. uralensis has become a key method to ensure supply. However, soil salinization poses challenges to G. uralensis cultivation and affects the yield and quality of it. In this study, the inhibitory effects of NaCl and Na2SO4 on yield and quality of G. uralensis were comprehensively evaluated in a three-year large-scale pot experiment, and the alleviating effects of supplementation with lanthanum nitrate (La (NO3)3) on G. uralensis were further evaluated under salt stress. The findings indicate that La (NO3)3 significantly strengthened the plant's salt tolerance by enhancing photosynthetic capacity, osmolyte accumulation, antioxidant defenses, and cellular balance of ions, which led to a substantial increase in root biomass and accumulation of major medicinal components. In comparison to the NaCl-stress treatment, the 0.75 M La (NO3)3 + NaCl treatment resulted in a 20% and 34% increase in taproot length and biomass, respectively, alongside a 52% and 43% rise in glycyrrhizic acid and glycyrrhizin content, respectively. Similar improvements were observed with 0.75 M La (NO3)3 + Na2SO4 treatment, which increased root length and biomass by 14% and 26%, respectively, and glycyrrhizic acid and glycyrrhizin content by 40% and 38%, respectively. The combined showed that application of La (NO3)3 not only significantly improved the salt resilience of G. uralensis, but also had a more pronounced alleviation of growth inhibition induced by NaCl compared to Na2SO4 stress except in the gas exchange parameters and root growth. This study provides a scientific basis for high-yield and high-quality cultivation of G. uralensis in saline soils and a new approach for other medicinal plants to improve their salt tolerance. Graphical Abstract

The taproot of Glycyrrhiza uralensis is globally appreciated for its medicinal and commercial value and is one of the most popular medicinal plants. With the decline of wild G. uralensis resources, cultivated G. uralensis has become a key method to ensure supply. However, soil salinization poses challenges to G. uralensis cultivation and affects the yield and quality of it. In this study, the inhibitory effects of NaCl and Na2SO4 on yield and quality of G. uralensis were comprehensively evaluated in a three-year large-scale pot experiment, and the alleviating effects of supplementation with lanthanum nitrate (La (NO3)3) on G. uralensis were further evaluated under salt stress. The findings indicate that La (NO3)3 significantly strengthened the plant's salt tolerance by enhancing photosynthetic capacity, osmolyte accumulation, antioxidant defenses, and cellular balance of ions, which led to a substantial increase in root biomass and accumulation of major medicinal components. In comparison to the NaCl-stress treatment, the 0.75 M La (NO3)3 + NaCl treatment resulted in a 20% and 34% increase in taproot length and biomass, respectively, alongside a 52% and 43% rise in glycyrrhizic acid and glycyrrhizin content, respectively. Similar improvements were observed with 0.75 M La (NO3)3 + Na2SO4 treatment, which increased root length and biomass by 14% and 26%, respectively, and glycyrrhizic acid and glycyrrhizin content by 40% and 38%, respectively. The combined showed that application of La (NO3)3 not only significantly improved the salt resilience of G. uralensis, but also had a more pronounced alleviation of growth inhibition induced by NaCl compared to Na2SO4 stress except in the gas exchange parameters and root growth. This study provides a scientific basis for high-yield and high-quality cultivation of G. uralensis in saline soils and a new approach for other medicinal plants to improve their salt tolerance. Highlights: 1. Novel Agricultural Application of Lanthanum: Our research delves into the innovative use of the rare earth element lanthanum in agriculture, with a particular focus on its potential to enhance the salt tolerance of medicinal plants. This work offers a fresh perspective on the multifaceted applications of rare earth elements in agricultural production. 2. Enhanced Salt Tolerance in Medicinal Plants. 3. Improved Plant Performance Under Salinity. 4. Strategic Implications for Medicinal Plant Cultivation. [ABSTRACT FROM AUTHOR]

The crustacean hyperglycemic hormone (CHH) is a multifunctional neuropeptide that plays a central role in crustacean metabolism and physiology. Experiments were conducted to examine the metabolic and osmoionic capabilities of the white shrimp Penaeus vannamei injected with its recombinant CHH-A (rCHHA) peptide and acutely transferred from iso-(26 ppt) to hypo- (10 ppt) and hyper-osmotic (40 ppt) conditions. Hemolymph glucose, protein, osmoregulatory capacity (OC), and ionoregulatory capacity (IC) for sodium, chloride, potassium, and calcium were evaluated at four post-injection times (0.5, 1, 2, and 24 h). The rCHH-A peptide had hyperglycemic activity in all salinity conditions, obtaining maximum values at 1 h post-injection. However, in shrimp transferred to hyper-osmotic condition, rCHH-A caused the most significant reductions in OC (2 h), chloride IC (2 h), and total proteins (0.5-2 h) compared to the phosphate-buffered saline (PBS) control. Contrastingly, in shrimp transferred to hypo-osmotic conditions, rCHH-A decreased OC significantly from 2-24 h, strongly decreased chloride and potassium IC at 1 h post-injection, and increased total protein concentration in the hemolymph (1-2 h) when compared to PBS control. Concerning calcium, the rCHH-A injection decreased calcium IC at 10 ppt (1 h) and 26 ppt (2 h), providing insight into a potential role for CHHA in calcium regulation. The results suggest that glucose and protein mobilization could enhance energy for osmo-ionic regulation under extreme osmotic conditions. This research study contributed to understanding crustacean endocrinology in P. vannamei and related euryhaline crustaceans. Further research should be performed to understand the osmo- and ionoregulatory mechanisms of the different CHH variants in crustaceans exposed to other stress conditions and the relationship with intermediary energy metabolism regulation. [ABSTRACT FROM AUTHOR]

The native area of gammarids from the so-called ‘Caspian complex’,Pontogammarus robustoides(G.O. Sars, 1894),Obesogammarus crassus(G.O. Sars, 1894),Dikerogammarus haemobaphes(Eichwald, 1841) andD. villosus(Sowinsky, 1894), is associated with brackish waters. Over the last several decades they have colonized the European inland waters and part of the brackish Baltic Sea. It is believed that anthropogenic increase in the salinity of inland waters facilitated their expansion. However, the influence of salinity on the dispersal of gammarid species outside their native area is not fully understood. We tested the hypothesis that salinity was a major factor in determining distribution, based on the abundance of Gammaridae in three coastal areas of low salinity (brackish Baltic), i.e. 0.3, 3.4 and 7.3 PSU, successfully inhabited by them. Additionally, for the first time, the effect of water salinity on the osmoregulatory capacity ofO. crassuswas examined under laboratory conditions, for the salinities given above. The experiments showed that similarly as in the case of other Caspian complex species, salinity values of about 7 PSU create better conditions for osmoregulation inO. crassusthan lower salinities (i.e. 0.3 and 3.4 PSU). In the environmental part of the study, we observed that onlyD. villosusachieved a significantly higher abundance in the area of 7.3 PSU. Thus, we concluded that in the range of 0.3–7.3 PSU, salinity is not a key factor governing the distribution of Ponto-Caspian gammarids. [ABSTRACT FROM PUBLISHER]

Red drum (Sciaenops ocellatus) is a euryhaline fish commonly found in the Gulf of Mexico and along the Atlantic coast of North America. Because of high commercial demand and its euryhaline characteristics, aquaculture of this species has diversified from marine to low-salinity aquaculture systems. In recent years, interest in the feasibility of producing red drum in inland freshwater systems has grown and this prompted us to investigate its osmoregulatory capacity after rearing for 8 months in a freshwater aquaculture system. We compared the activities of several genes and enzymes involved in the osmoregulatory process in freshwater-acclimatized (FW) and seawater (SW) red drum. The gene expression profiles were variable: the expression of genes encoding Na+/K+-ATPase (NKA) and the cystic fibrosis transmembrane regulator (CFTR) was slightly higher in SW than FW fish, while phosphoenolpyruvate carboxykinase (PEPCK) and the glucocorticoid receptor messenger RNA (mRNA) levels were higher in FW red drum. The total plasma K concentration was 60.3% lower, and gill NKA activity was 63.5% lower in FW than in SW fish. PEPCK activity was twofold higher in FW than in SW red drum. Similarly, liver glycogen was 60% higher in FW fish. In summary, both gene expression and the enzyme activity data support the phenotypic plasticity of red drum and suggest that the limited capacity for ion homeostasis observed, in particular the low plasma K concentration, was due to the composition of freshwater and does not necessarily reflect a physiological inability to osmoregulate. [ABSTRACT FROM AUTHOR]

The effects of dopamine (DA) on crustacean hyperglycemic hormone (CHH) release and osmoregulation were investigated in the white shrimpLitopenaeus vannamei. Application of 2 μg of the recombinant CHH-B1Hishormone or 2 × 10−6 mol L−1of DA to intact shrimp caused an increase in the hemolymph glucose levels 1 h post-injection, suggesting that DA might stimulate hyperglycemia through CHH release from the sinus glands. This assumption was supported by similar experiments using bilaterally eyestalk-ablated shrimp. Additionally, rCHH-B1Hisrestored the osmoregulatory capacity (OC) of shrimp under hyperosmotic conditions to basal values 2 h post-injection, whereas DA led to an OC decrease in shrimp at all sampling times. These neuroendocrine factors may be involved in the control of metabolism and osmoregulation inL. vannameiand could be important for its adaptation to different environmental conditions. [ABSTRACT FROM AUTHOR]

The study investigated the relationship between five moult stages and the osmoregulatory capacities (OC), moisture content of hepatopancreas (HM%), hepatosomatic indices (HIwet, HIdry) and growth of 6 weight classes of 235 marron (Cherax cainii) and 235 yabbies (Cherax destructor) under laboratory conditions. In each moult stage, OC increased linearly with the increase in wet body weight. Intermoult stage C showed the highest OC significantly lower than premoult stages D0, D1, D2and postmoult stage AB in every weight class in both crayfish. HM% decreased from AB to D2, while both HIwetand HIdryreduced from C to D2. Percentage dry matter of whole body carcass was highest in stage C and lowest during the AB stage with a significant difference between the two species. Larger than 15-g marron and yabbies differ with each other in OC, HIwet, and HIdry, moult intervals and growth rates. [ABSTRACT FROM AUTHOR]

The physiological responses of the blue shrimp were determined by exposing the organisms to temperatures of 23ºC, 28ºC and 33ºC, and salinities of 10, 15, 20, 25, 30, 35 and 40‰. Oxygen consumption of Litopenaeus stylirostris exposed to experimental salinities increased in direct relationship with temperature, even though at 28ºC the metabolic rate was steady. The ammonium excretion rate in juvenile shrimp acclimated at 23ºC and 33ºC was related to the pattern of osmoregulation, increasing when the shrimp were hyper-regulators and decreasing when they were hypo-regulators. The ammonium excretion rate remained constant in shrimp kept at 28ºC. The osmoregulatory capacity of the juveniles indicated that they were hypo-regulators and hyper-regulators in salinities above and below the isosmotic point, this capacity decreasing in organisms kept at 33ºC and exposed to higher salinities. The isosmotic point obtained ranged from 676.8 to 700.7 mmol kg–1 (23.7–24.6‰). The values of the slopes between the osmotic concentration of the external medium and the hemolymph of shrimp acclimated at 23ºC, 28ºC and 33ºC were 0.25, 0.17 and 0.3, respectively; the lowest value was obtained for juveniles maintained at 28ºC, being strong regulators in this condition. To optimize the culture of L. stylirostris under controlled conditions, we propose that it be cultivated in salinities of 25‰ and temperatures of 28ºC, considered the optimum conditions because in these environments the organisms are free of stress and their growth therefore increases.

Abstract: An 11-day trial was conducted to investigate the osmoregulatory capacity (OC) and regulation of K+, Na+, Ca2+ and Mg2+ of Penaeus monodon juveniles when exposed to K+ deficient inland saline water (ISW) of four different salinities (5, 15, 25 and 35 ppt). The survival of juveniles showed a positive linear relationship (R 2 ranging from 0.72 to 0.98) with salinity. At the end of the trial, juveniles were able to survive only in 5 ppt of ISW and showed no changes in OC when transferred from ocean water (OW) to ISW. Further, the OC of juveniles in 5 ppt of ISW was significantly different (P <0.05) from the OC of juveniles exposed to 15, 25 and 35 ppt and exhibited strong serum K+, Na+, Ca2+ and Mg2+ regulation monitored over 16 h. In contrast, at 35 ppt, significant decrease (P <0.05) in serum K+ and Mg2+ concentrations and accumulation of serum Na+ concentration occurred after 16 h of exposure to ISW. At higher salinity, an increase in serum Na+ concentration leads to an increase in the serum osmolality of the juveniles, which in turn causes decrease in the OC of the juveniles. The results of this study suggest that K+ deficiency in ISW has a negative effect on survival, OC and the ability of P. monodon juveniles to regulate serum Na+, K+, Ca2+ and Mg2+ concentrations. These effects are compounded as salinity increases. [Copyright &y& Elsevier]

Abstract: Growth, osmoregulatory capacity, ionic regulation and organosomatic indices of black tiger prawn (Penaeus monodon Fabricius, 1798) juveniles (2.6±0.2 g mean initial weight) were studied for 28 days in two water types namely inland saline water fortified with 100% K+ (ISW100) as in ocean water (OW) and OW. Three different salinities (5, 25 and 45 ppt) of each water type were prepared. No water type or salinity affected the survival of juveniles. The highest specific growth rate (SGR) was observed at 25 ppt in OW (4.7±0.2%/day) and ISW100 (4.1±0.1%/day). The serum osmolality was hyper-regulated and hypo-regulated in salinities below and above isosmotic points respectively. There was no significant difference (P >0.05) between osmoregulatory capacity (OC) of juveniles in ISW100 and OW at any salinity or time, except at 25 ppt. Except exoskeleton moisture content (EM%) of the juveniles reared in OW, there were no significant differences (P >0.05) among any organosomatic indices of the juveniles reared in ISW100 and OW. At 5 and 45 ppt, in both water types, serum Na+, K+ and Ca2+ concentrations were strongly regulated above and below isoionic points. However, the serum Mg2+ concentration was reduced below the medium Mg2+ concentrations at all salinities. The ability of P. monodon juveniles to regulate these ions in inland saline water (ISW) was improved by fortifying K+ in ISW to a similar level as in OW. The present trial thus augments the importance of fortification of K+ in ISW to a similar level as in OW for P. monodon culture. [Copyright &y& Elsevier]

In New Caledonia, the “syndrome 93,” which results in mass mortalities of farmed shrimp Penaeus stylirostris, occurs during the transitional and the cold seasons. The transitional season is characterized by an important fall in the average water temperature from 28 to 19 °C in 2 weeks. Besides this marked temperature fall, there are also nyctemeral temperature changes of up to 7 °C in 12 h. The cold season is characterized by an average water temperature of 19 °C with extreme lows of 14 °C. The objective of this study was to determine the effect of temperature and its variations on the osmoregulatory capacity of juvenile (7–10 g average weight) and subadult (25 g average weight) shrimps subjected to conditions of different salinity. A reduction in temperature level resulted in a decreased osmoregulatory capacity (OC) (defined as the difference between the osmolality of the haemolymph and that of sea water) at low salinity (hyper-CO) and at high salinity (hypo-CO), respectively, below and above the isoosmotic point (26.2 ppt). In subadult shrimps, the hyper-CO was affected when temperature dropped from 26 to 22 °C. The hypo-CO was modified only when temperature decreased down to 15 °C. Furthermore, the sensitiveness of osmoregulation to temperature changes was dependent on the developmental stage of the shrimp. Subadults were more sensitive than juvenile animals.The value of the isoosmotic point, which did not depend on the shrimp developmental stage, increased when temperature decreased to 17 or 15 °C.Our results provide an additional explanation of the “syndrome 93” and display the unfavourable influence of marked temperature drop on shrimp health. Our research could provide a possibility of seeking a nutritional and/or genetic solution to improve the capacity of the shrimps to maintain their homeostasis within a rearing medium with fluctuating temperatures. [Copyright &y& Elsevier]

Seawater adaptability of steelhead trout increases along with the increase in the size of the fish, independent of parr-smolt transformation. Three 96 h seawater challenge tests were conducted to determine the size at which seawater adaptability of steelhead trout develops. Plasma Na + and Cl - levels, moisture content, gill Na + /K + ATPase activity, and mortality during the 96 h after direct transfer to seawater (32 ppt) were determined. Plasma Na + and Cl - levels in 50 g fish continuously increased during the 96 h after the transfer to seawater ( p <0.05), but the levels in 100 and 150 g fish leveled off after 24 h ( p <0.05). Both 100 and 150 g size steelhead trout maintained muscle moisture content (%) better than 50 g size fish ( p <0.05). Gill Na + /K + ATPase activity in the 100 g size group increased in a time-dependent manner after transfer to seawater ( p <0.05), whereas activity in the 50 and 150 g sizes did not increase ( p >0.05), for which a possible explanation was discussed. A mere 2.6% mortality in both the 50 and 150 g size groups was observed. In conclusion, the current results indicate that 50 g size steelhead trout did not show development of a high level of hypoosmoregulatory capacity, whereas fish in the 100 and 150 g size groups showed a high level in our experimental conditions. Therefore, the steelhead trout larger than a 100 g size is recommended for transfer to seawater culture., Competing Interests: The authors declare no potential conflict of interest., (© Copyright 2020 The Korean Society of Developmental Biology.)