Environmental Stresses in Crop Sciences最新文献

{"title":"Evaluation of bread wheat genotypes under drought stress conditions in seedling stage using drought indices","authors":"Roghaieh Khojamli, K. Z. Nezhad, Ali Asghar Nasrollahnezhad Ghomi, S. Bagherikia","doi":"10.22077/ESCS.2020.3202.1820","DOIUrl":"https://doi.org/10.22077/ESCS.2020.3202.1820","url":null,"abstract":"Introduction \u0000The existence of drought stress at the beginning of the growing season is one of the most important threatening factors in wheat production of Iran. The coleoptile length is the most important morphological trait in determining sowing depth, emergence power and seedling establishment. The coleoptile length has been used as an effective indicator for selecting the drought tolerant genotypes in wheat breeding programs. Various indices have been developed to evaluate crop response to various stresses, including tolerance index (TOL), productivity mean (MP), geometric mean productivity (GMP), harmonic mean (HM), stress tolerance index (STI), stress sensitivity index (SSI), yield index (YI), yield stability index (YSI) and relative stress index (RSI). The efficiency of each indices depends on the breeding objectives and the target environment. \u0000Materials and methods \u0000In order to evaluate some of the landrace wheat genotypes under drought stress conditions at the seedling stage, an experiment with 35 pure lines under three moisture conditions (control, drought stress with PEG6000 10% and 15%) was conducted in a completely randomized design (CRD) with three replications at Gorgan university of agricultural sciences and natural resources.. The coleoptile length was measured after eight days. The indices of MP, GMP, HM, STI, SSI, YI, TOL, RSI and YSI were calculated based on the coleoptile length values under control (Yp) and stress (Ys) conditions. Data analysis was performed using iPASTIC: an online toolkit to estimate plant abiotic stress indices. \u0000Results and discussion \u0000In control and 10%-drought stress conditions, genotypes 11 and 2 had the highest of coleoptile length. While, in 15%-drought stress conditions, genotypes 3 and 6 had the highest of coleoptile length, respectively. Also in control and 15%-drought conditions genotypes 30 and 35 and in 10%-drought stress conditions genotypes 15 and 21 had the lowest of coleoptile length. Based on MP, GMP, HM, STI and YI indices, genotypes 2 and 11 were identified as tolerant genotypes, while genotypes 15, 21 and 30 were susceptible genotypes, under 10% drought stress conditions. Under 15%-drought stress conditions, MP, GMP, HM, STI and YI indices identified genotypes 21 and 34 as the most susceptible genotypes, whereas genotypes 30 and 35 were the most susceptible genotypes. Under three moisture conditions, the coleoptile length had the highest coefficient of correlation (positive and significant) with MP, GMP, HM and STI indices. Using three-dimensional plots, the genotypes were divided into four groups A, B, C, and D. The most appropriate indices being the ability to distinguish group A, from other groups. Group A selects genotypes that have high yield in both control and stress conditions. The result showed genotypes 3, 6, 11, 16, 19, 20 and 24 were classified as group A in both drought stress conditions. The Iranian commercial cultivars (genotypes 30, 34 and 35) placed in Group D, which","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43355813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the effect of different ratios of calcium to magnesium in irrigation water on growth characteristics and yield of grain quinoa (Chenopodium quinoa Willd.)","authors":"F. Dehghani, Parisa Malaki, M. Salehi, S. Saadat, H. Bahrami","doi":"10.22077/ESCS.2020.3198.1817","DOIUrl":"https://doi.org/10.22077/ESCS.2020.3198.1817","url":null,"abstract":"Introduction \u0000Quinoa (Chenopodium quinoa Willd.) is a facultative halophyte with very high adaptability to varied climatic conditions and high nutritional value. Different quinoa cultivars can have economical and stable yield in saline soil and water conditions. In addition to salinity, the chemical composition of irrigation water and thus soil solution affect the uptake and transfer of water and nutrients, and so plant yield. The intensity of this effect depends on various factors such as plant species. Calcium to magnesium ratio (Ca/Mg) is one of the quality indicators of irrigation water that can affect soil physical conditions and nutrient uptake independent of salinity level. A Ca/Mg < 1 and exchangeable magnesium percentage more than 25% in irrigation water are considered high enough to reduce soil quality and crop yields. Currently, frequent droughts and high water extraction have caused a sharp drop in water levels, increase in salinity, and in some cases a decrease in the Ca/Mg in the groundwater of most arid regions of the country. Since the effect of Ca/Mg in irrigation water on growth and yield of quinoa has not been studied so far, so the aim of this study was to investigate the effect of different Ca/Mg in irrigation water on growth parameters and quinoa grain yield in saline conditions. \u0000  \u0000Materials and methods \u0000To study the effect of different Ca/Mg of irrigation water on quinoa growth and yield, three separate experiments in a randomized complete block design with four replications were conducted at the Research Greenhouse of Soil and Water Research Institute in 2018. Experimental treatments included three different Ca/Mg in irrigation water consisting of 0.25, 0.5 and 1, which were made by sodium chloride, magnesium and calcium as nutrient solutions fit to the salinity tolerance threshold of quinoa at different growth stages. In the previous research, yield reduction thresholds for Titicaca cultivar at different growth stages in a soilless culture (perlite) were a: 8 dS m-1 for emergence, b: 15 dS m-1 for flowering and c: 20 dS m-1 for grain filling. To conduct this research, 100 quinoa seeds were planted in pots, and the pots were irrigated with 8 dS m-1 water along with the desired Ca/Mg treatments. After establishing the quinoa seedlings and thinning to six plants per pot, pot irrigation was done with 15 dS m-1 salinity along with the desired treatments. After ensuring the end of the flowering stage, the remaining pots were irrigated with 20 dS m-1 salinity with the desired treatments until physiological ripening. Finally, the analysis of variance of the data was performed using SAS software and the means were compared with the protected LSD at 5% probability level. \u0000  \u0000Results and discussion \u0000The results showed that the emergence percentage and non-uniformity of quinoa were not affected by Ca/Mg of irrigation water, however, increasing the magnesium amount significantly improved the emergence rate of quinoa seeds. Although ","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48612494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Screening of Kabuli-type chickpea genotypes for salinity tolerance under field condition","authors":"Z. Nasiri, J. Nabati, A. Nezami, M. Kafi","doi":"10.22077/ESCS.2020.3290.1839","DOIUrl":"https://doi.org/10.22077/ESCS.2020.3290.1839","url":null,"abstract":"IntroductionChickpea (Cicer arietinum L.) is one of the important legume crops and Globally, after beans )Phaseolus spp(., chickpea is ranked as a second important legume crop (Roy et al., 2010). Chickpea is an important source of proteins for human consumption, especially in the developing countries where people cannot provide animal protein or vegetarian by choice (Zaccardelli et al., 2013). Chickpea plays an important role in the maintenance of soil fertility through nitrogen fixation (Roy et al., 2010). Plants are exposed to wide range of environmental stresses. In among, Salinity is one of the major abiotic stresses causing severe impact on crop production worldwide(Rasool et al., 2012).chickpea is a salt sensitive pulse crop and its yield is seriously affected mainly by salts (Turner et al., 2013). Salinity stress in chickpea adversely affects several morphological features and physiological processes like reduction in growth and ion balance, water status, photosynthesis, increase in hydrogen peroxide, which causes lipid per oxidation and consequently membrane injury. Also proline and carbohydrates are accumulated in plant tissue (Flowers et al., 2010; Ashraf and Harris, 2004). This study is designed to determine the effect of salt stress on physiological and biochemical parameters in chickpea genotypes exhibiting differences in salinity tolerance. The results of this study could provide information on potential physiological and biochemical parameters and could also provide deeper intelligence into tolerance mechanisms than the stresses caused by salinity. \u0000Materials and methodsThis experiment was conducted as split-plot based on randomized complete block design with three replications in 2018 at Ferdowsi University of Mashhad, Mashhad, Iran. Salinity with two levels of 0.5 and 8 dSm-1 (NaCl) was considered as main plot and chickpea genotype (17 Kabuli-type genotypes) as sub-plot. The characteristics such as soluble carbohydrates, proline, osmotic potential, MDA, DPPH, relative water content, MSI%, were evaluated in 50% of flowering. At the end of the growing season, crop was harvested and seed yield were determined. \u0000Results and discussionThe highest proline and carbohydrates content was observed in MCC65, MCC92 and MCC95 genotypes, and the lowest in MCC12 genotype. Result salinity stress caused increased 24, 19 and 19 % in the amount of osmotic potential, MDA and DPPH. Relative leaf water content and membrane stability was showen respectively 10 and 13 % reduction by use salinity stress. Survival percentage, number of branches and canopy height had reduction 6, 22 and 57. MCC65, MCC92 and MCC95 genotypes respectively by 0.183, 0.193 and 0.181 (Kg.m-2) had the highest seed yield and MCC98 and MCC298 had the lowest seed yield. The MCC65, MCC95 and MCC92 genotypes had superior traits, including performance in stress conditions compared to other genotypes, and on the other hand, the MCC98 and MCC298 genotypes had the lowest performance. Amon","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48254549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative seed germination of Brassicaceae family weeds under salinity and drought stresses conditions","authors":"A. Zare, Maede Malekpoor Sharahki","doi":"10.22077/ESCS.2020.3304.1843","DOIUrl":"https://doi.org/10.22077/ESCS.2020.3304.1843","url":null,"abstract":"Introduction \u0000Knowledge on germination ecology of weeds in response to salinity and drought stresses can help to predict weeds population dynamics in the future. Among the family of weeds, the weeds of Brassicaceae family include many important species that contaminate crops and orchards. In addition to the presence of weeds, salinity and drought are also considered as limiting factors in agricultural production. Due to the increase in salinity and drought stresses in agricultural fields, it can be significant expansion and contamination of Brassicaceae weeds, because Physiological dormancy, abundant seed production and emergence at different time, leads to be persistent for long-term in soil. Therefore, the aim of this research was to compare the characteristics of seed germination of four weeds Brassicaceae family to salinity and drought stresses. \u0000Materials and methods \u0000In order to investigate the effects of salinity (0, 50, 100, 150, 200, 250, 300, 350 and 400 Mm) and drought stress (0, -0.2, -0.4, -0.6, -0.8, -1 and -1.2 MPa) on seed germination four Brassicaceae family weeds (Rocket (Eruca sativa), Hoary Mustard (Hirschfeldia incana), Wild Mustard (Sinapis arvensis) and Treacle Mustard (Erysimum repandum), two experiments as factorial based on completely randomized design (CRD) were conducted at agricultural sciences and natural resources university of Khuzestan in 2019 with three replications. Optimum Temperature for germination were selected 25°C for Rocket, Hoary Mustard, Wild Mustard and 15°C for Treacle Mustard. Duration of test for two experiments was considered 15 days. Criterion for germination was length radicle 2-3 mm. \u0000Results and discussion \u0000By increasing drought stress, germination, vigour index and germination rate were decreased and no germination was observed in drought stress of -1.2 MPa. 50% reduction for germination in four weeds Rocket, Hoary Mustard, Wild Mustard and Treacle Mustard were estimated in -1, -0.49, -0.76 and – 0.41 MPa of drought stress respectively. Drought stress required to reduce 50% of germination rate for Rocket, Hoary Mustard, Wild Mustard and Treacle Mustard were estimated -0.85, -0.35, -0.28 and 0.22 MPa respectively.The vigour index of Wild Mustard in conditions without drought stress treatment was more than other weeds. Rocket and Hoary Mustard were introduced as resistant and Wild Mustard was introduced as sensitive to salinity. The salinity required to reduce 50% of germination for Rocket, Hoary Mustard, Wild Mustard and Treacle Mustard were predicted 267, 162, 39 and 46 mM, while 50% reduction for germination rate were 174, 142, 27, 44 Mm respectively. By increasing salinity and drought stresses, mean germination time was increased and maximum mean germination time belonged to Treacle Mustard and the reason for this increase was the lag phase of germination. Germination rate in four weeds was more affected by salinity and drought stresses than germination percentage. Generally the germination ","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44782213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of urea and solopotass on morpho-physiological and biochemical characteristics of Super Sweet Corn (Zea mays var Basin) in response to different irrigation regimes","authors":"M. Ghanbari, A. Mokhtassi‐Bidgoli, K. M. Ghanaei-Pashaki, P. Saran","doi":"10.22077/ESCS.2020.3209.1823","DOIUrl":"https://doi.org/10.22077/ESCS.2020.3209.1823","url":null,"abstract":"Introduction Maize (Zea mays L.) is widely spread all over the world due to its many characteristics, especially its ability to adapt to different climatic conditions and occupies the third position after wheat and rice in terms of crop area. Currently, maize is cultivated in more than 240 hectares of Iranian land (Gheţe et al., 2018). Super Sweet Corn is a monocotyledonous, annual, single plant of the family poaceae, which is widely used in agriculture and industry (Gheţe et al., 2018). Abiotic stresses affect different aspects of plant growth, such as reduction and delay in germination, decrease in development rate, decrease in plant organs growth, and decrease in plant life duration and finally decrease in dry matter production. Among abiotic stresses, drought stress is considered to be the most influential type of stress in the production of oil seeds in the world and can greatly reduce production on many arable lands. One of the primary effects of drought is the reduction of water content of plant tissues (Ghanbari et al., 2016). Nitrogen is one of the major nutrients in biomass determination and crop yield through impact on leaf area index (radiation intake) and photosynthetic capacity per leaf area unit (Compelo et al., 2019). Potassium in physiological applications including: carbohydrate metabolism or starch formation; protein metabolism; control and regulation of various essential minerals activities; Stomach and water play a key role (Tisdale et al. 2003). This study was carried out to investigate the effect of urea fertilizers combination with solopotass fertilizers on yield and yield components of Super Sweet Corn in different irrigation regimes. Materials and methods This research was carried out as a factorial experiment in a randomized complete block design with three replications in Varamin Agricultural & Livestock Complex in 2016. Factorial combinations of three treatments of water deficit stress (15% (un-stressed control), 30% (moderate stress) and 45% (severe stress) of FC depletion), four nitrogen fertilizer rate (zero (un-fertilized control), 150, 200 and 250 kg.ha-1) from urea and four potassium fertilizer rate (zero (un-fertilized control), 100, 150 and 200 kg.ha-1) from potassium sulfate were considered. Drip irrigation (T-tape) was applied the row length in each experimental plot was 6 m, 50 cm apart. The distance between the plots and between the repetitions was 1 and 3.5 m, respectively. Plant to plant distance within each row was 8 cm. The irrigation schedules were based on soil moisture discharge of field capacity at the root zone of Super Sweet Corn with a depth of about 30 cm. Results The results of this study showed that three-way interaction of irrigation time and chemical fertilizers was significant in leaf length and diameter, grain number, 1000 grain weight, photosynthesis rate and catalase enzyme. In moderate stress conditions, the highest grain yield was obtained from 150 kg urea and 200 kg solopot","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42190250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on expression of transcription factors AP2-Domain, HD-ZIP, WRKY and MYB in oily sunflower (Helianthus annuus L.) under drought stress","authors":"E. Akbari, R. Darvishzadeh, Babak Abdollahi, S. Besharat","doi":"10.22077/ESCS.2020.2979.1769","DOIUrl":"https://doi.org/10.22077/ESCS.2020.2979.1769","url":null,"abstract":"IntroductionSunflower (Helianthuse annuus L.) is an annual plant from Composite with a chromosome number of 2n = 2x = 34 which is widely cultivated for supplying edible oil. Drought is one of the most important environmental stresses that limits the growth and distribution of plant more than other factors. This plant is classified as semi-tolerant to drought stress; however, its performance is negatively affected by drought. Transcription factors are molecules that play an important role in the understanding and transmission of stress messages as well as many physiological processes. One of the most effective ways to deal with stress is to produce resistant hybrids. Investigation and study of expression of genes post stress application and identification of genes involved in resistance and especially regulatory genes such as transcription factors is vital and necessary for molecular breeding programs. Materials and methodsIn order to investigate the effect of drought stress on the expression of transcription factors: AP2-Domain, HD-ZIP, WRKY and MYB in oilseed sunflower, two lines with different susceptibility to drought stress were selected and cultivated in a completely randomized design with three replications in greenhouse. The seeds were planted in 3 cm depth of 30 × 25 cm pots containing farm soil and sand mixture in the ratio of 2:1. The plants were grown in controlled conditions at 25 ± 3 °C, 65% relative humidity and 12 h dark-light photoperiod and were irrigated regularly at 100% of field capacity up to 8-leaf stage. After this stage, a number of pots were kept at the same field capacity however, some other were exposed to 80, 60 and 40% of field capacity. Samplings were done in two times, one and three weeks after drought stress application. The study of the expression of genes was performed using real time PCR by SYBR Green method. RNA extraction kit RNX-plusTM (Sinoclon Co., Iran) and complementary DNA (cDNA) synthesis Kit (Fermentas LIFE SCIENCE # K1621) were used according to the manufacturer's protocols. Quantitative reverse transcription-PCR (qRT-PCR) was performed in triplet using 6.25 μl of Maxima SYBR Green/ Fluorescein qPCR Master Mix (2X) (Thermo Fisher Scientific, Germany), 5 pM of forward and reverse primers and 50 ng of cDNA for each reaction in a final volume of 12.5μl. Relative gene expression was analyzed by comparative Ct method, 2−ΔΔC. Target gene was normalized by the reference gene, ACTIN and calibrated for each sample against the control. Results and discussionThe results of statistical analyzes showed that the expression of the genes in the susceptible and resistant lines of sunflower is different. Mean comparisons of expression of AP2-Domain, WRKY and MYB transcription factors in the two genotypes ENSAT254 (tolerant) and LC1064C (susceptible) showed that the expression level was not tangible in the first week after drought stress application, but the expression of genes was increased in 40% of field capacity in ","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":"14 1","pages":"569-583"},"PeriodicalIF":0.0,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45749014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of millet (Panicum miliaceum) response to humic acid, silicon and mycorrhiza application under saline-sodic irrigation water stress","authors":"Mohammad Ahmadi, A. Astaraei, A. Lakzian, H. Emami","doi":"10.22077/ESCS.2020.2842.1782","DOIUrl":"https://doi.org/10.22077/ESCS.2020.2842.1782","url":null,"abstract":"IntroductionSalinity and sodicity stresses are the major problems in the production of crops under arid and semi-arid regions. Sustainable management by using water and soil resources, under conditions of salinity and sodicity, is considered as a management strategies, also application of mycorrhizal fungi along/or organic matter such as humic acid addition are the major causes in reclamation of the environment and also increases the stability of agro-systems by reducing the use of chemical fertilizers. Among other ways to overcome the negative effects of salinity on the growth and yield of the plant, application of ordinary silicon and silicon nanoparticles have prior importance. This research was conducted to evaluate the effect of humic acid, mycorrhiza and silicon (ordinary and nano) on yield and nutrient content of millet under saline-sodic irrigation water. \u0000Materials and methodsA field experiment was conducted as split plot factorial in a randomized complete block design with three replications in summer 2015. The study area is located in Tabas city, South Khorasan province (Iran) with longitude 56o 53' and latitude 33o 34'. The main plots consisted of saline-sodic irrigation water (S) at two levels (S1= EC: 2.1 dSm-1, SAR:11.5 and S2= EC: 5.04 dSm-1, SAR: 20.8) and a combination of sub factors including three treatments of silicon salts (SI): (control (Si0), silicon nanoparticles, 10KgSiha-1 (NSi) and ordinary silicon (by using sodium silicate salt) 10KgSiha-1 (Si)) and three levels of mycorrhiza and Humic acid (MH): (control (MH0), inoculation with Glomus mosseae mycorrhizal fungi (M) and humic acid 10Kgha-1 (H)) as The factorial was placed in the main plots. \u0000Results and discussion The results showed that increasing salinity-sodicity of irrigation water decreased grain yield, straw yield, number of panicles per square meter and plant height and its effect on 1000 seed weight and grain number per spike were not significant. Increasing salinity-sodicity of irrigation water decreased the grain yield by reducing the number of panicles per square meter, reduction of the straw yield due to its negative impact in plant height. The application of silicon nanoparticles treatment increased the grain yield compared to non-silicon treatment, but ordinary silicon (sodium silicate) had no effect. Mycorrhizal inoculation increased grain yield, straw yield and panicle per square meter and application of humic acid also increased grain yield, number of panicles per square meter. Mean grain yield at S1 level increased with the use of humic acid and mycorrhiza and in S2 level, mean grain yield increased only with the use of humic acid. Saline-Sodic irrigation water reduced the concentrations of nitrogen, phosphorus, potassium and K/Na ratio, and increased sodium concentration in millet. Application of silicon had no significant effect on nitrogen, phosphorus, potassium, sodium and K/Na ratio in the plant, but mycorrhiza and humic acid increased plant phos","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47171381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of salinity stress on the amount of proline, chlorophyll and sodium and potassium ions in different rice cultivars in hydroponic environment","authors":"Somayeh Kamrava, N. B. Jelodar, N. Bagheri","doi":"10.22077/ESCS.2020.3078.1791","DOIUrl":"https://doi.org/10.22077/ESCS.2020.3078.1791","url":null,"abstract":"Introduction Among the cereals, rice is the most important human food source after wheat and has a major place in human nutrition in terms of production and cultivation. This plant is susceptible to salt stress and its response to salt stress varies with growth stages, concentration and duration of impact. Materials and methods This study was carried out in factorial experiment in a completely randomized design with three replications in the research greenhouse of Sari University of Agricultural Sciences and Natural Resources in 1977-98. The first factor was 71 rice genotypes and the second factor was salinity stress with 4 levels. The germinated seeds were transferred to hydroponic medium to prepare the culture medium from Yoshida nutrient solution (Yoshida et al., 1994). Chlorophyll extraction of rice leaf by Arnon method (1997), Proline amino acid extraction from leaf tissue by Bets et al. (1973) and for determination of sodium and potassium ions from leaf by Hamada and Elnai method (1994) used. The data obtained from these traits were analyzed by SAS and SPSS statistical software and compared by means of Duncan's multiple range test and clustering of genotypes by cluster analysis of tolerant cultivars based on this. Attributes were identified. Results and discussion Results of analysis of variance for different physiological traits under salinity stress showed that genotype, salinity and their interaction effects were statistically significant at the 5% probability level for all measured traits. Comparison of mean salinity levels in all measured traits was significant at 5% probability level. It showed that proline amino acid content and leaf tissue sodium content increased with increasing salinity and zero (normal) level with minimum and salinity level 9 The highest Ds was obtained and the chlorophyll pigment and potassium content of leaf tissue decreased with increasing salinity level and the highest (zero) level and the lowest salinity level was 9 dS / m. Within plant cells, proline acts as an osmotic preserving agent between the cytoplasm and the cell vacuole, and proline protects the plant against free radical damage. In the present experiment, proline content increased significantly with increasing salinity dose. This increase was higher in tolerant cultivars than in susceptible cultivars. An important effect of increasing salinity is leaf senescence and the main factor causing leaf senescence is the decrease in chlorophyll content under salinity stress. In this study, total chlorophyll a, chlorophyll a and chlorophyll b also decreased significantly under salinity stress, which was in line with the results of Bori Boncast et al. (2013) and (Wijita et al., 2018). Higher concentrations of potassium ions in the leaves of tolerant cultivars exposed to salinity can be a adaptive response to high potassium ion storage in stomach cells in salinity stress (Fallah 2015). Aerial is one of the mechanisms of plant tolerance against salinity stress.","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":"14 1","pages":"805-821"},"PeriodicalIF":0.0,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45115334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of nitrogen and phosphorus fertilizers on yield and nutrient efficiency indices in maize under drought stress","authors":"S. Bahamin, A. Koocheki, M. Mahallati, Seyed Alireza Behashti","doi":"10.22077/ESCS.2020.3095.1793","DOIUrl":"https://doi.org/10.22077/ESCS.2020.3095.1793","url":null,"abstract":"Introduction Reduced use efficiency of important elements such as phosphorus and nitrogen has led to higher costs for corn production, reduced economic efficiency of fertilizers and greater environmental impacts due to increased use of these fertilizers. The use of nitrogen-stabilizing biological fertilizers is a potential alternative that can minimize these negative effects. Materials and methods For this purpose, a split factorial layout with 4 replications based on randomized complete block design was conducted two consecutive years (2016 and 2017) at the Agricultural Research Station of Mehran in East of Ilam province. The studied factors included irrigation in 3 levels including non-stress, drought stress based on 75% and 50% field capacity. In sub-plots, two factors were factorial. The first sub-factor included nitrogen fertilizer at 100% fertilizer requirement (Net nitrogen) through urea, control and Azotobacter biological fertilizer. Another sub-factor included 100% phosphorus fertilizer (Net phosphorus) in the form of triple superphosphate, control and Pseudomonas biological fertilizer applied. Results The results of this study showed that interaction of stress, nitrogen and phosphorus on seed yield were significant. The highest seed yield (11932 kg ha-1) was obtained in irrigation with Azotobacter and Pseudomonas. However, there was a significant difference at the same level of stress associated with Azotobacter and triple superphosphate (11873 kg ha-1) and irrigation treatment with Pseudomonas and urea (11318 kg ha-1). Furthermore, at all levels of stress and consumption of Azotobacter and triple superphosphate, grain yield increased compared to control treatment. The interaction of stress, nitrogen and Phosphorus had significant effect on nitrogen productivity. The highest nitrogen productivity was obtained in non-stress treatment and inoculation of Azotobacter and Pseudomonas with 54.04 kg kg -1. At all irrigation levels, Azotobacter inoculation along with Pseudomonas aeruginosa increased nitrogen productivity. Conclusion The results of this study showed that Pseudomonas and Azotobacter bacteria, both low (100% capacity) and severe (50% capacity) water stress conditions, possibly by increasing food absorption caused to increased the quantitative and qualitative yield of maize.","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":"14 1","pages":"675-690"},"PeriodicalIF":0.0,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43351036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the effect of moisture stress on the shift in optimal and maximum temperatures for germination of Malva parviflora L. seeds: Introducing a new hydrothermal time model","authors":"M. R. M. Telavat, S. A. Siadat, A. Derakhshan, S. Safarkhanzadeh","doi":"10.22077/ESCS.2020.2806.1732","DOIUrl":"https://doi.org/10.22077/ESCS.2020.2806.1732","url":null,"abstract":"Introduction \u0000Seed germination is largely controlled by the temperature and moisture content of the seedbed. Therefore, hydrothermal time models have been widely used to describe seed germination patterns in response to temperature and water potential (Ψ) of the seedbed. The majority of these models assume a Normal distribution for base water potential (Ψb(g)) to describe the variation in time to germination. In some of these models, it is assumed that the thermoinhibition of germination induced by the shift in Ψb(g) to more positive values occur only at temperatures above the optimum (To) and that the To is independent of drought stress levels. In this study, the Weibull hydrothermal time was used to quantify the Ψb(g) changes in response to temperature and to model the effect of drought stress on the shift in the optimal (To(g)) and maximum (Tm(g)) temperatures for different germination fractions of malva parviflora seeds. \u0000  \u0000Materials and methods \u0000The experiment was conducted at the Seed Technology Laboratory of Agricultural Sciences and Natural Resources University of Khuzestan in 2016. Germination test was performed at eight constant temperatures of 8, 12, 16, 20, 24, 28, 32 and 36 (± 0.2) °C in light/dark conditions (12 h/12 h). In each of the above temperature regimes, seed germination response to different levels of drought stress, i.e. osmotic solutions with concentrations of 0, -0.2, -0.4, -0.6, -0.8 and -0.1 MPa was evaluated. Germination test was performed with four replications (each Petri dish as one replicate). In each replicate, 50 seeds were placed on a layer of Whatman No 1 filter paper in a 9 cm glass Petri dish, and then moistened with 7 ml distilled water or other osmotic solutions. The number of germinated seeds was counted twice every day until germination stopped at each temperature regime (when no germination occurred for 5 consecutive days). All models, having been formulated into the hydrotime and then hydrothermal models, were fitted to data using PROC NLMIXED procedure of SAS software version 9.4. \u0000  \u0000Results and discussion \u0000While Ψb(g) showed a linear increase in the temperature range between Tb (base temperature) and Tm(g), the hydrotime constant (θH) decreased nonlinearly in response to increasing temperature. Based on the relationship between Ψb(g) and θH, the shape of the germination rate (GR(g)) response to temperature in the hydrothermal time model was curvilinear. The model estimated the values of θHT (hydrothermal time constant), Tb, Ψbase (base water potential at Tb), and KT (slope of the Ψb(g) response to temperature) as 1800.04 MPa °C h, 4.20 °C, -2.46 MPa, and 0.064 MPa °C-1, respectively. Both To(g) and Tm(g) decreased proportionally with increasing drought intensity and became cooler for higher germination percentiles. For example, the estimated To(50) (optimal temperature for the median) for M. parviflora seeds germinated under no water stress (Ψ=0 MPa) was 23.38 °C but dropped to 15.59 °C as water av","PeriodicalId":31378,"journal":{"name":"Environmental Stresses in Crop Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47203378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}