Evaluate salinity stress in Mystus gulio to explore potential farming in brackish water

Salinity stress induces various types of ultrastructural changes in higher plant cells. These structural changes provide useful information as to the underlying mechanism of salinity stress. In this report the ultrastructural effects of salinity (NaCl) stress in crop plants especially in rice are described based on the research work conducted in our laboratory. Relevant research results are also described and the possible mechanisms of ultrastructural changes are discussed. 1. EFFECTS OF SALINITY STRESS ON ROOT CELL ULTRASTRUCTURE Salinity is one of the most serious problems that limit plant growth and crop yield. Salinity affects almost 10 9 ha of land, which corresponds to 7% of the global land surface (1). In addition about 5% of the cultivated land is affected by salinity (2) and about 20% of irrigated land is suffering from secondary salinization due to inappropriate treatment of irrigation system (3). Therefore, salinity stress is an important research subject to increase global agricultural production to cope with the increasing world population. There have been a number of studies on physiological and molecular biological responses of plants to salinity (4, 5), but information is also accumulating on the ultrastructure of plants under salinity. Salinity stress induces various types of ultrastructural changes in higher plant cells. These structural changes provide useful information as to the underlying mechanism of salinity stress. They would also provide some insight into practical methods to cope with the salinity stress in crop plants. In this report the ultrastructural effects of salinity (NaCl) stress in crop plants especially in rice are described based on the research work conducted in our laboratory. Relevant research results are also described and the possible mechanisms of ultrastructural changes are discussed.

Saffron stigmas are widely used as food additives and as traditional medicine in Iran and many other countries. The unique taste, flavor and pharmaceutical properties of saffron stigmas are due to the presence of three apocarotenoids secondary metabolites crocin, picrocrocin and safranal. There is limited knowledge about the effect of environmental stresses on the metabolism of apocarotenoids in saffron. We analyzed the content of crocin and picrocrocin and the expression of key genes of apocarotenoid biosynthesis pathways (CsCCD2, CsCCD4, CsUGT2, CsCHY-β and CsLCYB) in saffron plants exposed to moderate (90mM) and high (150mM) salt (NaCl)concentrations. Measuring ion concentrations in leaves showed an increased accumulation of Na+ and decreased uptake of K+ in salt treated compared to control plants indicating an effective salt stress. HPLC analysis of apocarotenoids revealed that crocin production was significantly halted (P < 0.05) with increasing salt concentration while picrocrocin level did not change with moderate salt but significantly dropped by high salt concentration. Real-time PCR analysis revealed a progressive decrease in transcript levels of CsUGT2 and CsLCYB genes with increasing salt concentration (P < 0.05). The expression of CsCCD2 and CsCHY-β tolerated moderate salt concentration but significantly downregulated with high salt concentration. CsCCD4 however responded differently to salt concentration being decreased with moderate salt but increased at higher salt concentration. Our result suggested that salt stress had an adverse effect on the production of saffron apocarotenoids and it is likely influencing the quality of saffron stigma produced.

Background: Salt stress is a significant environmental factor that affects plant growth and productivity, particularly in regions with increasing soil salinization. Understanding the impact of different salt types and concentrations on seed germination and seedling vigor is crucial for developing strategies to mitigate salinity stress in agricultural settings. This study evaluates the effects of NaCl and KCl at varying concentrations on the germination and seedling vigor of the Goksu chickpea cultivar (Cicer arietinum L.). Methods: The study was conducted at Gaziantep University, Nurdagi Vocational School between November 2022 and January 2023. This study evaluates the effects of different salt types (NaCl and KCl) and their varying concentrations on the germination and seedling vigor of the Goksu chickpea cultivar. The experiment was conducted under controlled conditions with seven different concentrations of each salt (0, 25, 50, 75, 100, 125 and 150 mm). Result: It is indicated that increasing salt concentrations had a negative impact on all measured parameters. GP decreased significantly with higher salt levels, with NaCl treatments generally exhibiting higher GP compared to KCl. The MGT increased with higher salt concentrations, reflecting the delayed germination process under salinity stress. Both radicle and PL were adversely affected, with NaCl having a more pronounced negative impact compared to KCl. The GI, CVG and SVI also decreased significantly with higher salt concentrations, demonstrating the overall decline in seedling vigor under salinity stress.

We compared the effects of saline stress (9:1 molar ratio of NaCl : Na2SO4, pH 6.44–6.65) and alkaline stress (9:1 molar ratio of NaHCO3 : Na2CO3, pH 8.71–8.89) on the germination, growth, photosynthesis, ionic balance and activity of anti-oxidant enzymes of Lathyrus quinquenervius to elucidate the physiological adaptive mechanism of plants to alkaline stress (high pH). The results showed that, at a low stress intensity, the effects of saline stress and alkaline stress on L. quinquenervius were similar. Compared with saline stress, high alkaline stress intensity clearly inhibited germination, growth, photosynthesis and root system activity, and led to a sharp increase in Na+ and an ion imbalance in the shoots, as well as enhanced H2O2 and malondialdehyde content, resulting in severe intracellular oxidative stress. The results indicated that the accumulation of organic acid was a central adaptive mechanism by which L. quinquenervius maintained intracellular ionic balance under alkaline stress. Lathyrus quinquenervius may enhance organic acid synthesis to remedy the shortage of negative charge resulting from the massive influx of Na+ and decreased inorganic anions. In addition, saline stress and low alkaline stress slightly enhanced the activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX), but did not affect catalase (CAT) activity. However, strong alkaline stress significantly enhanced the activities of SOD and APX, and reduced CAT activity. We propose that enhancing the activities of SOD and APX may be a vital mechanism by which L. quinquenervius resists oxidative stress caused by alkaline stress.

بیوچار به عنوان منبع کربن آلی و اصلاح کننده خاک، در کشاورزی مورد توجه است و خصوصیات آن تحت تاثیر دمای پیرولیز قرار می‌گیرد. در پژوهش حاضر جهت تهیه بیوچار، مخلوط کود گاوی و گوسفندی به مدت چهار ساعت در دما 300، 400، 500 و 600 درجه سانتی‌گراد، پیرولیز شد. سپس با هدف ارزیابی تاثیر بیوچار حاصل از دماهای مختلف پیرولیز (صفر، 300، 400، 500 و 600 درجه سانتی‌گراد) بر رشد گیاه همیشه بهار تحت شرایط تنش شوری (صفر، 4، 8 و 12 دسی­زیمنس­برمتر)، آزمایشی به صورت فاکتوریل در قالب طرح کاملاً تصادفی در گلخانه مرکز آموزش عالی کشاورزی بردسیر-کرمان، در سال 1398 اجرا گردید. با افزایش دمای پیرولیز به 600 درجه سانتی‌گراد، اسیدیته و هدایت الکتریکی بیوچار به‌ترتیب 16/29 و 60/37 درصد افزایش و عملکرد بیوچار (52/28 درصد) و چگالی ظاهری (48/10 درصد) آن کاهش یافت. محتوای خاکستر نیز 1/5 برابر شد. همچنین با افزایش شوری ارتفاع ساقه، تعداد و سطح برگ کاهش یافت. در تنش 12 دسی­زیمنس­برمتر و دمای پیرولیز 600 درجه سانتی‌گراد، میزان پتاسیم و پرولین برگ افزایش یافت. بیشترین فعالیت آنزیم کاتالاز، آسکوربات پراکسیداز و گایاکول پراکسیداز در تیمار بیوچار دمای 600 درجه و تنش 8 و 4 دسی­زیمنس برمتر مشاهده شد. درمجموع، شوری بیوچار مهمترین خصوصیات نامطلوب آن می‌باشد که با افزایش دمای پیرولیز این ویژگی منفی شدت می‌یابد، لذا توصیه برای استفاده از بیوچار در خاک‌های شور نیازمند به مطالعات بیشتری می‌باشد. در پژوهش حاضر استفاده از بیوچار در شرایط تنش شوری تاثیر مثبت قابل ملاحظه­ای در ایجاد مقاومت در گیاه همیشه بهار و تحمل تنش شوری نداشت.

We conducted a study to examine the growth and physiological changes in 12 different ecotypes of Sesuvium portulacastrum collected from Hainan Island in China. These ecotypes were subjected to different concentrations (0, 200, 400, and 600 mmol/L) of sodium chloride (NaCl) salt stress for 14 days. We also analyzed the expression of metabolic genes related to stress response. Under low salt stress, indicators such as plant height in region K (0 mmol/L: 45% and highest at 200 mmol/L: 80%), internode length (0 mmol/L: 0.38, 200 mmol/L: 0.87, 400 mmol/L: 0.25, and 600 mmol/L: 1.35), as well as leaf area, relative water content, fresh weight, and dry weight exhibited an overall increasing trend with the increase in salt concentration. However, as the salt concentration increased, these indicators showed a decreasing trend. Proline and malondialdehyde contents increased with higher salt concentrations. When the NaCl concentration was 400 mmol/L, MDA content in the leaves was highest in the regions E (196.23%), F (94.28%), J (170.10%), and K (136.08%) as compared to the control group, respectively. Most materials demonstrated a significant decrease in chlorophyll a, chlorophyll b, and total chlorophyll content compared to the control group. Furthermore, the ratio of chlorophyll a to chlorophyll b (Rab) varied among different materials. Using principal component analysis, we identified three ecotypes (L from Xinglong Village, Danzhou City; B from Shuigoupo Village, Lingshui County; and J from Haidongfang Park, Dongfang City) that represented high, medium, and low salt tolerance levels, respectively, based on the above growth and physiological indexes. To further investigate the expression changes of related genes at the transcriptional level, we employed qRT-PCR. The results showed that the relative expression of SpP5CS1, SpLOX1, and SpLOX1 genes increased with higher salt concentrations, which corresponded to the accumulation of proline and malondialdehyde content, respectively. However, the relative expression of SpCHL1a and SpCHL1b did not exhibit a consistent pattern. This study contributes to our understanding of the salt tolerance mechanism in the true halophyte S. portulacastrum, providing a solid theoretical foundation for further research in this field.

Salinity is a major constraint in crop production in saline prone areas of Bangladesh. Therefore, a study was carried out in order to investigate the effect of different levels of NaCl salinity stress on seed germination and seedling growth of tomato. This study was consisted with five varieties of tomato (BARI Tomato-2, BARI Tomato-3, BARI Tomato-4, BARI Tomato-14, and BARI Tomato-15) and four levels of NaCl salt solution (0, 50, 100 and 150 mM). Seeds were placed in petridish for germination and the seedlings were allowed to grow for ten days. Results showed that percent seed germination decreased with increasing salt concentration in the germinating media. The highest seed germination (68.25%) was recorded in untreated control (0 mM) condition and the lowest in 150 mM salt solution ((5.92%). In combination of variety and salt concentration, BARI Tomato-2 gave the highest germination (88.33%) under 0 mM salinity condition and the lowest (2.92%) in BARI Tomato-3 with 150 mM salt solution. However, percent germination, germination coefficient, radicle and plumule length, seedling vigor index, fresh weight of plumule and radicle, mean germination time, germination index decreased with increasing salt concentration as compared to untreated control condition. The findings indicated that BARI Tomato- 2, BARI Tomato-4 and BARI Tomato-15 were relatively tolerant to salt stress than BARI Tomato-3 and BARI Tomato-14. J Bangladesh Agril Univ 17(4): 490–499, 2019

شوری یکی از تنش­های محیطی است که سبب اختلال در جذب یون‌های ضروری و درنتیجه محدودیت در رشد گیاهان می­شود. کاهش رشد یک نوع سازگاری برای زنده ماندن گیاه در شرایط تنش است.در سالیان اخیر ماده آلی بیوچار به دلیل کاربرد آن در اصلاح خاک بسیار موردتوجه قرار گرفته است. به‌منظور بررسی تأثیر بیوچار بر خصوصیات رشدی، غلظت سدیم و پتاسیم گیاه مرزه تابستانه (Satureja hortensis L.) آزمایشی گلدانی به‌صورت فاکتوریل در قالب طرح کاملاً تصادفی با چهار تکرار در گلخانه گروه باغبانی دانشکده کشاورزی دانشگاه فردوسی مشهد در سال 1396 اجرا شد. فاکتورهای آزمایش شامل ماده آلی بیوچار در سه سطح (0، 1 و 2 درصد وزنی خاک هر گلدان) و آبیاری با آب‌شور در 3 سطح شوری (0، 40، 80 میلی­مولار کلرید سدیم) بود. نتایج حاصل از این تحقیق نشان داد که اثرات متقابل شوری و کاربرد بیوچار بر خصوصیات رشدی موردمطالعه معنی­دار بود. مقایسه میانگین داده­ها نشان داد که بیشترین ارتفاع بوته، تعداد شاخه فرعی، تعداد گره، قطر ساقه، وزن تر و خشک ساقه، وزن تر و خشک برگ در تیمار کاربرد 2 درصد بیوچار بدون شوری مشاهده شد. همچنین با افزایش غلظت نمک، میزان سدیم برگ مرزه افزایش یافت و از میزان پتاسیم و نسبت پتاسیم به سدیم آن کاسته شد. به‌طورکلی، شوری با اختلال در میزان جذب پتاسیم و کاهش نسبت پتاسیم به سدیم گیاه سبب کاهش صفات رشدی موردمطالعه در مرزه گردید و بیوچار با جذب یون‌های نمک سبب بهبود صفات رشدی مرزه تابستانه در تیمارهای شوری گردید.

This paper selected clonal cutting seedlings from the F1 hybrid varieties of Physocarpus amurensis Maxim (♀) × Physocarpus opulifolius “Diabolo” (♂) as research material to study the response of the photosynthetic gas exchange parameters and chlorophyll fluorescence parameters of Physocarpus amurensis hybrids and their parental leaves to NaCl stress (with concentrations of 0, 50, 100 and 200 mmol·L-1). The results showed that under saline stress, the stomatal conductance (Gs), transpiration rate (Tr), and net photosynthetic rate (Pn) of the three kinds of P. amurensis all significantly decreased. When the NaCl concentration was below 100 mmol·L-1, the intercellular CO2 concentration (Ci) of leaves of the three samples declined with the increase of salt concentration; however, when the concentration increased to 200 mmol·L-1, Ci did not decrease significantly, especially when the Ci of P. opulifolius “Diabolo” presented a slight increase. This indicated that the decline of photosynthetic carbon assimilation capacity induced by saline stress was the consequence of interaction between stomatal factors and non-stomatal factors, and the non-stomatal factors played an important role when the saline concentration was below 200 mmol·L-1. Compared with P. amurensis, the photosynthetic gas exchange capability of P. opulifolius “Diabolo” leaves was more sensitive to saline stress, and the limitation of non-stomatal factors was relatively evident, but the photosynthetic capacity of hybrid Physocarpus amurensis Maxim leaves with the desired purple color was improved compared with Physocarpus amurensis. Under saline stress, the PSII activity of the three kinds of P. amurensis leaves declined, the electron transfer was inhibited, and obvious signs of photoinhibition were present. With the increase of saline concentration, the Vk of P. amurensis and hybrid P. amurensis leaves presented a decreasing trend, but the Vk of P. opulifolius “Diabolo” leaves increased slightly. This suggested that the effects of saline stress on the oxygen-evolving complex (OEC) of the three P. amurensis sample types were relatively limited and only the OEC of P.s opulifolius “Diabolo” leaves were slightly sensitive to saline stress. The VJ of all the leaves of the three Physocarpus amurensis types increased under saline stress, and increased significantly when the saline concentration increased to 200 mmol·L-1, indicating that saline stress obviously impeded the electron transfer chain from QA to QB on the PSII receptor side of the leaves. Moreover, high saline concentrations would cause thylakoid membrane dissociation.The salt tolerance of photosynthetic functions of hybrid Physocarpus amurensis (♀) × Physocarpus opulifolius “Diabolo” (♂) leaves was improved compared with that of parental Physocarpus opulifolius “Diabolo,” and the hybrid shows obvious hybrid vigor in the aspect of photosynthesis.

This study was conducted to explore the effects of salinity stress on spikelets formation and grains filling in rice. To analyze the effects of salinity stress on the differentiation and degradation of spikelets, development of floral organs, and grain-filling characteristics in rice, conventional <italic>japonica</italic> rice Nanjing 9108 and Yandao 12 were used with three salinity treatments under pot-cultivation conditions, control (CK, 0 salt concentration), medium-salinity stress (MS, 0.15% salt concentration), and high-salinity stress (HS, 0.3% salt concentration). As a result, compared with the CK, (1) rice grain yield was decreased under salinity stress. The grain yield of Nanjing 9108 was decreased by 18.7% and 54.5%, and Yandao 12 was decreased by 24.3% and 58.6%, under MS and HS treatments, respectively. (2) the number of spikelets per panicle was decreased under salinity stress. The number of spikelets per panicle of Nanjing 9108 was 8.6% and 19.8%, and Yandao 12 was 8.0% and 25.9% lower than that of CK under MS and HS treatments, respectively. Besides, the filled-grain percentage and grain weight of Nanjing 9108 and Yandao 12 under MS and HS were also significantly lower than CK. (3) the number of differentiated and survived spikelets was decreased, while the number of retrograded spikelets and its rate was increased under salinity stress. Salinity stress reduced the differentiated and survived spikelets on the primary and secondary branches, while increased retrograded spikelets. The decline in the number of differentiated and survived spikelets on the secondary branches were higher than those of primary branches, and the similar observations were also for the increase in the number of retrograded spikelets. (4) the length, width, and volume of anther were decreased under salinity stress, and the similar trends were also observed for dehiscence rate of anther, pollen vigor, and the length and width of spikelets. Our results suggested that, salinity stress could inhibit the differentiation of rice spikelets and promote the degradation of spikelets, resulting in a significant decrease in the number of spikelets per panicle; it adversely affected the development of floral organs and reduced the fullness of grains, which significantly deteriorated the characteristics of grain plumpness.

Seeds germination and seedlings growth of Cucumis sativus and Solanum lycopersicum were monitored in in vitro and in vivo experiments after application of different concentrations of NaCl (25, 50, 100 and 200 mM). Photosynthetic pigments content and the biochemical responses of C. sativus and S. lycopersicum were assessed. Salinity stress slightly delayed the seeds germination rate and significantly reduced the percentage of germination as well as shoot length under the highest salt concentration (200 mM) in cucumber. Furthermore, root length was decreased significantly in all treatments. Whereas, in tomato, a prominent delay in seeds germination rate, the germination percentage and seedlings growth (shoot and root lengths) were significantly influenced under all concentrations of NaCl. Fresh and dry weights were reduced prominently in tomato compared to cucumber. Photosynthetic pigments content was reduced but with pronounced decreasing in tomato compared to cucumber. Secondary metabolites profiling in both plants under stress was varied from tomato to cucumber. The content of saponins, proline and total antioxidant capacity was reduced more prominently in tomato as compared to cucumber. On the other hand, the content of phenolics and flavonoids was increased in both plants with pronounced increase in tomato particularly under the highest level of salinity stress. The metabolomic profiling in stressful plants was significantly influenced by salinity stress and some bioactive secondary metabolites was enhanced in both cucumber and tomato plants. The enhancement of secondary metabolites under salinity stress may explain the tolerance and sensitivity of cucumber and tomato under salinity stress. The metabolomic evaluation combined with multivariate data analysis revealed a similar mechanism of action of plants to mediate stress, with variant level of this response in both plant species. Based on these results, the effect of salinity stress on seeds germination, seedlings growth and metabolomic content of plants was discussed in terms of tolerance and sensitivity of plants to salinity stress.

Saline and osmotic stress are the main abiotic factors limiting the productivity of rice and other crop plants. Although both coincide in generating water deficit and affect many aspects of plant growth and development similarly, some effects of salinity are distinctively related to the ionic component of salt stress. At the cellular level, dessication tolerance is largely dependent on the cell's ability for osmotic adjustment. Here, we have studied the effects of saline and osmotic stress on endocytosis by rice cells, to investigate the common and distinctive effects of saline-generated stress and osmotically generated stress, and the possible involvement of endocytosis in tolerance mechanisms. For this purpose, we have used rice cell lines with different levels of tolerance and biotinylated bovine serum albumin (bBSA) as an endocytic marker, which in our previous experiments has been shown to enter rice cells by a process with the characteristics of receptor-mediated endocytosis. Our results indicate that the pattern of uptake is common to both types of stress. Thus, when rice cells were subjected to saline or osmotic stress there was an initial dose-dependent inhibition of uptake. However, after more extended stress periods, there was an activation of uptake in the stressed cells. This late activation appears mainly related to the inhibition of growth commonly caused by the different stress agents used in this study. When using cell lines with different degrees of tolerance, the level of uptake activation varied as a function of the type of stress. Thus, under osmotic stress, a higher stress tolerance was directly related to a higher bBSA uptake, while the opposite occurred under saline stress. The possible role of endocytosis in the cellular responses to osmotic and saline stress is discussed.

Summary The effects of salinity on some agro-physiological properties, such as dry matter, nutrient contents, chlorophyll contents, and ionic balance, of maize plants were investigated. Plants were treated with six salt sources (NaCl, Na 2 SO 4 , CaCl 2 , CaSO 4 , MgCl 2 and MgSO 4 ) at four concentrations (0, 40, 80 and 120 mM) for 30 days in a growth medium. Salt type and concentration affected soil pH and electrical conductivity. Soil salinity affected the parameters considered and changed the nutrient balance of the plants. High salt concentration caused substantial reduction in plant growth. Different salt concentrations negatively affected plant dry weight. The highest decrease rates of plant dry weight were obtained for NaCl application followed by Na 2 SO 4 , CaCl 2 , MgCl 2 , CaSO 4 and MgSO 4 . Total chlorophyll and nitrate contents of the plants decreased with increasing salt concentrations, and the lowest value was obtained for NaCl application. Proline contents of the plants were increased with increasing salt concentrations, and the highest value was obtained for 120 mM NaCl application. The effects of salt concentrations on N, K and P contents of the plants were significant. The highest reduction rate was determined with NaCl application, but the lowest with MgSO 4 . Fe, Mn and Cu contents of the plants showed similar variation: the highest reduction was recorded with NaCl and the lowest with CaCl 2 . The highest decrease in Zn content occurred with MgSO 4 application, but the lowest with NaCl.

Leymus chinensis is a dominant and most promising grass species in the Songnen Grassland of Northern China. Experiments were conducted to determine the effect of temperature, salinity, alkalinity and their interactions on seed germination. Seeds were germinated at four alternating temperatures (10–20, 15–25, 20–30 and 25–35°C), with saline stress (9:1 molar ratio of NaCl:Na2SO4) and alkaline stress (9:1 molar ratio of Na2CO3:NaHCO3). Germination percentage and rate were inhibited by either an increase or decrease in temperature from the optimal temperature range of 20–30°C, and were also inhibited by an increase in salinity and alkalinity at all temperatures. The inhibitory effects of high salinity on germination were greater at 25–35°C, but seeds were subjected to more stress even though the alkalinity was low under this temperature. Recovery percentage was highest at 400 mm salinity at 20–30°C, but only at 100 mm alkalinity, and 25–35°C also resulted in lower recovery percentage under both stresses. Results suggest that saline stress and alkaline stress have different impacts on seed germination and that saline‐alkaline tolerance of L. chinensis seeds is affected by the interactions of temperature and salinity‐alkalinity. Early July sowing in the field is recommended when temperature is optimal and salinity‐alkalinity concentrations are reduced by the high rainfall.

The aim of the current study is to assess the growth response, biochemical changes, photosynthetic pigments content and gas exchanges of physic nut (Jatropha curcas) grown under natural saline conditions.The experiment was arranged in a completely randomized design based on the following soil electrical conductivities: 0.29 dS.m -1 (control), 1.76 dS.m -1 (moderate salt concentration), 2.61 dS.m -1 (high salt concentration), 3.79 dS.m -1 (very high salt concentration).Physic nut plants were kept under saline conditions for 19 days in greenhouse.Plant growth analyses were performed on a weekly basis.Plant biomass allocation was quantified at the end of the experiment.Leaf gas exchange, stomatal conductance, Fv/Fm and quantum yield were quantified 102 days after planting.Photosynthetic pigments, amino acids, proline and carbohydrates in fresh leaf tissue were also quantified.The leaf antioxidant enzymes catalase (CAT) and ascorbate peroxidase (APX) were quantified.Although there was no alteration in biomass allocation, the initial growth of J. curcas was gradually reduced by increasing salt concentration, which was observed through reduced plant height, stem diameter, and total number of leaves.Soil electrical conductivity 3.79 dS.m -1 was lethal to seedlings.Seedlings exposed to salt stress had their photosynthesis, stomatal conductance, transpiration and effective photochemical efficiency reduced, and their catalase and ascorbate peroxidase enzyme activity increased.Amino acids, proline and carbohydrate concentrations increased due to salt stress, whereas there was decrease in the chlorophyll content.J. curcas is sensitive to soil salinity at electrical conductivity levels higher than 1.76 dS.m -1 .To some extent, salinity effects can be relieved by osmolyte accumulation and by greater antioxidant activity; however, these factors were not sufficient to keep plant growth within normal rates.-1 .De Lima et al. (2015) also found decreased leaf dry weight (by 47.3%) and stem dry weight (by 43.2%) in castor bean 120 days after planting at irrigation water EC 3.9 dS m -1. The most commonly used method to set the sensitivity to salinity of J. curcas is the saline irrigation water (Campos et