Water Restriction Conditions Research Articles

MORPHOPHYSIOLOGICAL CHANGES IN SEEDLINGS OF Eugenia uniflora L. AFTER CHEMICAL HARDENING

Using quality seedlings increases the chances of survival and development after planting. Hardening aims to modify the morphology of seedlings to acclimatize them to stressful field conditions. The objective of this study was to quantify the effects of chemical hardening with methyl jasmonate on the morphophysiology of Eugenia uniflora L. seedlings subjected to 12 days of water deficit. Seedlings were hardened with doses of 0, 50, 100, and 150 μmol L-1 of methyl jasmonate (MeJA). Afterward, they were transplanted into pots with soil and subjected to water deficit for 12 days. During that period, we assessed shoot height (H), stem diameter (SD), leaf area (LA), leaf dry mass (LDM), stem dry mass (SDM), root dry mass (RDM), total dry mass (TDM), relative water content (RWC), robustness index (RI), Dickson quality index (DQI), shoot/root ratio (S/R), stomatal conductance (Sc) and evapotranspiration (ET). The experiment was conducted in a randomized block design with five blocks. Variables RI, DQI, LA, RWC, and TDM values presented a quadratic trend, with promising results from the 50 and 100 µmol L-1 doses. Sc and ET values were influenced by water deficit. Under conditions of water restriction, application of MeJA in adequate doses promoted morphophysiological changes and induced defense strategies in E. uniflora seedlings. Doses of methyl jasmonate between 50 and 100 µmol L-1 resulted in seedlings with greater tolerance to water deficit for 12 days.

Reconstruction and analysis of the gene regulatory network for cell wall function in Arabidopsis thaliana L. leaves in response to water deficit.

The plant cell wall represents the outer compartment of the plant cell, which provides a physical barrier and triggers signaling cascades under the influence of biotic and abiotic stressors. Drought is a factor that negatively affects both plant growth and development. Cell wall proteins (CWP) play an important role in the plant response to water deficit. The adaptation mechanisms of the cell wall to water loss are of interest for identifying important genetic factors determining plant drought resistance and provide valuable information on biomarkers for further selection aimed at increasing the yield of crop plants. Using ANDSystem, a gene network describing the regulation of CWPs under water restriction conditions was reconstructed. The analysis of the gene network and the transcriptome data analysis allowed prioritizing transcription factors (TF) based on their enrichment of differentially expressed genes regulated by them. As a result, scores were calculated, acting as indicators of the association of TFs with water deficit. On the basis of the score values, eight most significant TFs were selected. The highest priority was given to the TF GBF3. CWPs were prioritized according to the criterion of summing up the scores of transcription factors regulating these genes. Among the most prioritized CWPs were the AT5G03350 gene encoding a lectin-like protein, AT4G20860 encoding BBE-like 22 required for the oxidation of cellulose degradation products, and AT4G37800 encoding xyloglucan endotransglucosylase/ hydrolase 7. Overall, the implemented algorithm could be used for prediction of regulatory interactions between transcription factors and target genes encoding cell wall proteins in plants.

Osmoregulatory and Antioxidants Modulation by Salicylic Acid and Methionine in Cowpea Plants under the Water Restriction.

Global climate changes have intensified water stress in arid and semi-arid regions, reducing plant growth and yield. In this scenario, the present study aimed to evaluate the mitigating action of salicylic acid and methionine in cowpea cultivars under water restriction conditions. An experiment was conducted in a completely randomized design with treatments set up in a 2 × 5 factorial arrangement corresponding to two cowpea cultivars (BRS Novaera and BRS Pajeú) and five treatments of water replenishment, salicylic acid, and methionine. After eight days, water stress decreased the Ψw, leaf area, and fresh mass and increased the total soluble sugars and catalase activity in the two cultivars. After sixteen days, water stress increased the activity of the superoxide dismutase and ascorbate peroxidase enzymes and decreased the total soluble sugars content and catalase activity of BRS Pajeú plants. This stress response was intensified in the BRS Pajeú plants sprayed with salicylic acid and the BRS Novaera plants with salicylic acid or methionine. BRS Pajeú is more tolerant to water stress than BRS Novaera; therefore, the regulations induced by the isolated application of salicylic acid and methionine were more intense in BRS Novaera, stimulating the tolerance mechanism of this cultivar to water stress.

Management of Digitaria insularis in soybean pre-sowing desiccation by ACCase alternative herbicides and its impact on soybean carryover

The objective of this study was to evaluate the use of alternative herbicides to ACCase inhibitors to control Digitaria insularis (sourgrass) during pre-sowing soybean desiccation. Two field experiments were conducted with two temporal replicates under different climatic conditions, with the following treatments: imazethapyr + glyphosate, clethodim + fluroxypyr, chlorimuron + glyphosate, imazapic + imazapyr, mesotrione + atrazine + glyphosate, tembotrione + atrazine + glyphosate, nicosulfuron + atrazine and imazamox + glyphosate, all of which were composed of a sequential application of glufosinate ammonium. The water stress conditions in experiment 1 compromised the efficacy of acetolactate synthase enzyme (ALS) inhibitor herbicides in the control of sourgrass. Even under water restriction conditions, the treatments containing mesotrione + atrazine + glyphosate and tembotrione + atrazine + glyphosate provided control greater than 80%. In experiment 2, the combination of ALS inhibitors with glyphosate proved to be a great alternative for the management of sourgrass control. All treatments showed no significant phytotoxicity in soybean for either experiment.

Effect of the application of vermicompost and millicompost humic acids about the soybean microbiome under water restriction conditions.

Humic substances (HSs) are constituent fractions of organic matter and are highly complex and biologically active. These substances include humic acids (HA), fulvic acids (FA), and humin. HS are known to stimulate the root system and plant growth and to mitigate stress damage, including hydric stress. Humic acids have already been reported to increase microbial growth, affecting their beneficial effect on plants. However, there is scarce information on whether HA from vermicompost and millicompost, along with Bradyrhizobium, improves the tolerance of soybean to water restriction. This study aimed to evaluate the responses of soybean plants to the application of vermicompost HA (HA-V) and millicompost (HA-M) along with Bradyrhizobium sp. under water restriction. The experiment was carried out in a greenhouse, and the treatments received Bradyrhizobium sp. inoculation with or without the application of HA from vermicompost and millicompost with or without water restriction. The results showed that HA provided greater soybean growth and nodulation than the control. The application of HA-M stimulated an increase in the richness of bacterial species in roots compared to the other treatments. After the application of water stress, the difference between the treatments disappeared. Microbial taxa were differentially abundant in plants, with the fungal fraction most affected by HA application in stressed roots. HA-V appears to be more prominent in inducing taxa under stress conditions. Although the results showed slight differences between HA from vermicompost and millicompost regarding plant growth, both humic acids promoted an increase in plant development compared to the control.

Changes in aquaporins expression due to acute water restriction in naturally aging mice.

Aquaporins (AQPs) are water channels in the cell membrane that regulate osmosis in response to rapid changes in intracellular and extracellular fluid concentration caused by extrinsic factors. While there are so many studies on the association of AQPs with muscular atrophy, sarcopenia, and Duchenne muscular dystrophy (DMD), the expression of AQP has not been verified in naturally aging mice or humans. Notably, due to the characteristics of AQPs, the difference in function cannot be evaluated without extrinsic factors such as acute water restriction. The purpose of this study was to investigate the changes in AQPs expression and function due to natural aging under acute water restriction conditions in aging mice. The expression of AQP4 was shown to decrease with aging similar to previous studies. However, for the first time, this study results confirmed that AQP1 expression increased in aging mice. In addition, the expression of Aqp1 decreased in the acute water restricted group compared to the control group after acute water restriction in aging mice. These results suggest that although the expression of AQP1 increases with aging, its function is reduced. We also confirmed that overexpression of Aqp1 can inhibit myotube differentiation and that knockdown can promote myotube differentiation through in vitro experiments. In conclusion, based on our results, we suggest that the AQP1 is an important factor in sarcopenia caused by natural aging accompanied by chronic dehydration.

Response of Potted Citrus Trees Subjected to Water Deficit Irrigation with the Application of Superabsorbent Polyacrylamide Polymers

Searching for new strategies to mitigate the effects of low water availability for citrus production, a study was carried out on potted mandarin cv. W. Murcott, with the objective of evaluating the physiological and growth response of the plants to polyacrylamide gel application in the substrate in water restriction conditions. The following treatments were evaluated, T0 (control) with 100% ETc water replenishment, T1 with 50% ETc water replenishment, and T2 with 50% ETc water replenishment plus the application of polyacrylamide polymers to the substrate. Temperature and water volumetric content (ϴ: m3 m−3) were evaluated in the substrate. Plant water-status parameters such as stem water potential (SWP), stomatal conductance (gs), and chlorophyll fluorescence (Fv/Fm), as well as biomass, nutrients levels, and proline biosynthesis were measured in the plants in response to the treatments. The results showed that the substrate moisture for T2 was kept significantly higher than T0 and T1, despite receiving the same irrigation rate as T1 and a half of T0; however, this higher moisture availability in the substrate of T2 was not reflected in the plant’s water status or growth. On the contrary, the T2 plants showed responses such as lower total biomass, lower vegetative development, and lower root biomass, as well as a higher concentration of proline in the root. According to these results, it is concluded that polymers such as polyacrylamide sodium allow the retention of water in the substrate, but do not necessarily release that water for plants, probably because that moisture is kept in the hydrogel and not released to the substrate media or the roots, or if released, in this case, this occurs with an increase in the concentration of sodium available to the plants, which could lead the citrus crop to a worse situation of water and/or osmotic stress.

Bacillus subtilis Inoculation Improves Nutrient Uptake and Physiological Activity in Sugarcane under Drought Stress.

Sugarcane (Saccharum spp.) is one of the most important crops in the world. Throughout the sugarcane’s growth stages, periods of drought are common, causing detrimental effects on plant growth. Therefore, the search for strategies for minimizing the impact of drought on sugarcane development is of great interest. Plant growth-promoting bacteria hold the potential for improving tolerance to drought in agricultural systems. Thus, the present study aimed to evaluate whether inoculation with Bacillus subtilis can reduce the negative effects of drought on the nutritional, physiological, and morphological characteristics of sugarcane plants. For this, sugarcane was cultivated in a greenhouse, under controlled conditions of water and temperature, with the aid of four treatments: without and with inoculation of B. subtilis, in normal conditions of water availability, and in conditions of water restriction (2 × 2 factorial), with four replications. In treatments with inoculation, the pre-emerged seedlings were immersed in a B. subtilis solution and transplanted into experimental pots. Our results showed that inoculation with B. subtilis improved plant nutrition and chlorophyll concentrations. As a result, the gas exchange parameters (especially net photosynthetic rate and water use efficiency) were also improved, even under drought conditions. In addition, stress parameters (antioxidant metabolism activity) were reduced in inoculated plants. The sum of these beneficial effects resulted in increased root growth, tillering, stalk weight, and higher sucrose concentration in the stalks.

The Impact of Irrigation on Olive Fruit Yield and Oil Quality in a Humid Climate

The expansion of olive orchards into regions with no tradition of olive production and humid climates, such as Uruguay, with more than 1200 mm of annual rainfall, calls into question the need for irrigation. In these regions, however, years with water deficit during summers are quite common. The vapor pressure deficit during summer is lower than in countries with a Mediterranean climate. The high variability in interannual water availability in the current context of climate change, with a growing tendency for extreme events to occur, emphasizes the need to evaluate the production response of olive trees to irrigation. To achieve this, three irrigation treatments were applied to Arbequina and Frantoio cultivars according to the value of the maximum crop evapotranspiration: a first treatment applying 100% ETc, corresponding to being fully irrigated; a second treatment applying 50% ETc; and a third treatment in which neither irrigation nor rain inputs occurred from the end of the pit hardening period until harvest. Results show the possibility of an increasing fruit weight and pulp/pit ratio through irrigation in the local environmental conditions. The oil content in response to irrigation was different within cultivars. Water restriction conditions did not affect the oil content of olives in Arbequina, while in Frantoio it increased it. Polyphenols in fruit increased under water stress for both cultivars. The technological applicability of the results obtained must be accompanied by an economic analysis. The results obtained highlight the need for better use of irrigation water during the growth and ripening phase of the olive fruit under a humid climate.

Do brassinosteroids alleviate water stress in seedlings of Handroanthus serratifolius?

AbstractLimited water availability in reforestation areas can compromise plant growth and development, especially for plants at early stages. In this context, the exogenous application of growth regulators, such as brassinosteroids (BRs), can be used to mitigate the negative effects of water restriction. The aim of this study was to evaluate the effect of the application of BRs (90% brassinolide + a brassinosteroid) on initial growth, gas exchange, leaf water potential and leaf anatomy in yellow Ipê (Handroanthus serratifolius), under water restriction conditions. Throughout the experimental period, plants were maintained in two different water regimes: WR1—plants maintained at 100% of the pot capacity; WR2—plants rehydrated with 50% of the evapotranspiration from the previous day. BRs were applied on three occasions during the experimental period, in five concentrations: C1, 0 g/L (application of distilled water); C2, 0.25 g/L; C3, 0.5 g/L; C4, 0.75 g/L; and C5, 1.00 g/L. The dry mass, root:shoot ratio, water status and leaf anatomy traits were evaluated at the end of the experimental period and were analysed in two‐level factorial scheme (2WR × 5BRs concentrations). The plant height, number of leaves, gas exchange and leaf chlorophyll content were evaluated four times during the experimental period and were analysed in a split‐split‐plot design (two WR × five BRs concentrations × four evaluation times). The differences between the means were evaluated by analysis of variance (ANOVA). Pairs of means were separated using the standard error of the difference between the means (SED) and the Fisher's protected least significant difference test (LSD) at p < .05. In addition, all variables were subjected to regression analysis, being the variables evaluated over time, analysed through a two‐stage modelling approach. The results obtained indicate that the water deficit led to reductions in growth and gas exchange parameters, regardless of the exogenous application of the regulator; therefore, higher concentrations (C4 and C5) were the most harmful for the maintenance of metabolic and photosynthetic activity. The exogenous application of BRs in H. serratifolius plants attenuated the effects of water limitation on the leaf water potential, but was not able to mitigate for the negative effects in growth, gas exchange and leaf anatomy.

Soybean Agronomic Performance Does Not Change with Gypsum Application in a Cambisol Submitted to Water Restriction in Southern Brazil

Water stress is one of the main limiting factors for soybean crop development, and it may increase due to subsurface soil acidity. The use of agricultural gypsum is a way to improve the soil’s chemical conditions at depth and mitigate the undesirable effects caused by water restriction during drought periods. This study aimed to evaluate whether gypsum application increases soybean yield in water restriction conditions. The experiment was implemented in 2018 in a Humic Cambisol, Southern Brazil. The treatments consisted of two gypsum management procedures (with 1.4 Mg ha-1 and without application) associated with two water conditions (with and without water restriction). The water conditions were promoted by partially covering the soil with plastic tarpaulin sheets, and the of agricultural gypsum used was 1,400 kg ha-1. Soybean was grown in the crop years 2018/19 and 2019/20 to assess root attributes and yield and were analyzed soil’s chemical characteristics. Water restriction reduced soybean yield by 11.4 and 36.8% in the 2018/19 and 2019/20 harvests, respectively, whereas there was no response to gypsum application. The plants’ root system was not affected by the water conditions or gypsum management. It was concluded that water restriction reduces soybean yield, and agricultural gypsum does not mitigate such loss under de evaluated conditions, even though it positively changes some soil chemical parameters.

Baccharis trimera (Less.) DC responses to water restriction

Climate change can cause imbalances in plants. Baccharis trimera is a specie usually found in harsh conditions and has medicinal and agricultural properties. Thus, this study aimed to evaluate the biochemical and physiological responses of this plant under water restriction (WR) levels. B. trimera samples were identified and collected in Erechim/RS and propagated in a greenhouse. When acclimated, they were subjected to 0, 25, 75 and 100% WR, determined according to the water saturation in the soil by capillary action. After 30 days of treatment, the physiological responses: growth, and fresh and dry biomass; and the biochemical responses: activity of superoxide dismutase (SOD), guaiacol peroxidase (GP) and ascorbate peroxidase (APX) enzymes, proline, protein and hydrogen peroxide content, and lipid peroxidation, were determined. Data were submitted to regression analysis and Pearson correlation. The WR of 27.37%, on average, induced an increase in physiological parameters, but the root growth was impaired in conditions above 50% of WR. With the increase in WR there was an increase in the activity of SOD in the shoot and APX in the root. In low WR conditions, proline contents were maintained. Therefore, with low levels of WR, around 27%, B. trimera has increase in root growth and root and shoot biomass. Proline, and SOD and APX activity are a pathway that scavenging the stress generated by WR on B. trimera.

Interaction of irrigation rates and fertilization doses on postharvest quality of papaya ‘Formosa ’

Water deficit is a water-saving strategy that might nevertheless negatively affect fruit quality. In the present study, the papaya quality was evaluated after application of different irrigation rates and nitrogen fertilization doses at harvest and postharvest. The study was conducted on ‘Formosa’ cultivar in semiarid region. The experiment was performed in a completely randomized design in a 2 x 5 x 3 scheme; two storage times (0 and 5 days), five irrigation rates (50, 75, 100, 125, and 150% of crop evapotranspiration), and three nitrogen doses (150, 180, and 210 Kg.ha-1), with four replicates. Total Soluble Solids (TSS), Titratable Acidity (TA), and fruit skin colour (Luminosity - L, intensity of green/red coloration - a*, and intensity of yellow coloration - b*) were evaluated. Reduced irrigation rates and lower nitrogen doses resulted in increased soluble solids and SS/TA ratio. The latter was increased during storage. Irrigation deficit and a lower amount of nitrogen (150 Kg. ha-1) did not reduce papaya quality, even after 5 days of storage in an environment with controlled temperature and humidity. In order to ensure net productivity in rural properties, this water-saving strategy of maintaining the crop under water restriction conditions must take into consideration not only in the curves of papaya quality-related variables, but also fruit productivity curve

Protective action of priming agents on Urochloa brizantha seeds under water restriction and salinity conditions

Abstract: Analyses of germination of seeds under artificial stress conditions are tools for a better understanding of the survival and adaptation capacity of species under natural stress conditions. Therefore, the aim of this study was to evaluate the effect of priming on seed germination, on breaking of dormancy, and on the length of Urochloa brizantha seedlings under water restriction and salt stress conditions. A completely randomized experimental design was used with four replications in a 3 × 6 factorial arrangement consisting of 3 germination conditions (water, water restriction with PEG, and salinity with NaCl) and 6 treatments [five priming solutions (distilled water, potassium nitrate, spermidine, gibberellin, and sodium nitroprusside) and a control (unprimed seeds)]. The following determinations were made: seed moisture content after priming (before drying) and after drying the seeds, germination test at seven and twenty-one days after sowing, germination speed index, viability by the tetrazolium test of the seeds remaining from the germination test, and seedling length. Priming is effective in minimizing the negative effects of water restriction and salinity. Use of sodium nitroprusside as a priming solution results in a lower percentage of dormant seeds and greater germination, vigor, and plant development.

Coinoculação do amendoim (Arachis hypogaea L.) com Bradyrhizobium e Azospirillum promove maior tolerância à seca

O uso de rizobactérias promotoras de crescimento pode ser uma estratégia de manejo para amenizar os efeitos da deficiência hídrica no crescimento e no desenvolvimento das plantas por modificar o metabolismo fisiológico e promover maior tolerância à seca. Este estudo teve como objetivo investigar os efeitos da inoculação das sementes com Bradyrhizobium japonicum e Azospirillum brasilense de forma isolada e combinada no crescimento e na indução da tolerância das plantas de amendoim (Arachis hypogaea L., cv. RUNNER IAC 886) à restrição hídrica. O delineamento experimental adotado foi o de blocos ao acaso em esquema fatorial 3 × 4, constituídos por três níveis de irrigação [100% da capacidade de retenção de água do solo (controle), 50% do controle (estresse moderado) e 25% do controle (estresse severo)] e por quatro tratamentos de inoculação [controle (sem inoculação), inoculação com B. japonicum, inoculação com A. brasilense e coinoculação das sementes com B. japonicum e A. brasilense, com quatro repetições. A restrição hídrica foi imposta no início do aparecimento do ginóforo, aos 40 dias após a emergência das plantas, por um período de 18 dias. As plantas expostas as condições de restrição hídrica severa tiveram redução de a altura da planta (32%), área foliar (44%), volume radicular (47%), matéria seca da parte aérea (35%) e na matéria seca das raízes (37%) quando comparadas às plantas em condições controle. A inoculação com B. japonicum e A. brasilense de forma isolada ou combinada melhorou a integridade da membrana plasmática em 7% e reduziu em 8% as perdas de água das folhas de amendoim expostas à deficiência hídrica. A inoculação com A. brasilense de forma isolada ou combinada com B. japonicum resultou em maior altura de planta (21%) e maior matéria seca das raízes (23%) quando comparado as plantas não inoculadas sob condições de restrição hídrica severa. Nossos resultados sugerem que inoculação com B. japonicum e A. brasilense de forma isolada ou combinada pode amenizar os efeitos adversos da deficiência hídrica, mantendo o crescimento e o acúmulo de matéria seca das plantas quando expostas à restrição hídrica. Portanto, o uso destas rizobactérias na cultura do amendoim pode ser uma alternativa de manejo em condições de cultivo sujeitas a ocorrência de deficiência hídrica por conferir maior tolerância das plantas à seca.

Morphological and Biochemical Responses of Poincianella Pyramidalis Seedlings Subjected to Water Restriction

Abstract Catingueira (Poincianella pyramidalis Tul. L. P. Queiroz) is an endemic species of the Caatinga, with great economic potential. Research on the development of this species under conditions of water restriction, common in the Northeastern semi-arid region, is still scarce. This study evaluated the effects of water restriction on the morphological and biochemical characteristics of catingueira seedlings subjected to water restriction. The experimental design was a randomized complete block design, with five treatments and four replicates. The treatments consisted of periods of water restriction (0, 6, 12, 18 and 24 days without irrigation). The characters evaluated were shoot height, leaf diameter, number of leaves, leaf area, total dry mass, ratio between shoot height and dry mass, Dickson quality index, chlorophylls a and b content, total soluble sugars and free proline. Periods of water restriction longer than six days caused damage to the seedlings development, with reduced growth and quality.

Permanent wilt point from two methods for different combinations of citrus rootstock

ABSTRACT: Considering that water is extremely important in agricultural production, but with restricted availability in some Brazilian regions, this research sought to identify the water limit for the rootstocks: Cleóptra tangerine (Citrus reshni hort. Ex Tan), Volkamer lime (Citrus Volkameriano Pasquale), Citrandarin ‘indio’ (TSK X TRENG 256), Santa Cruz Rangpur lime (Citrus × limonia) and Sunki Tropical tangerine (Citrus sunki HORT. EX TAN) grafted orange ‘Pera’ (Citrus sinensis), obtained by two methods: the traditional method of determining the permanent wilting point described by SHANTZ & BRIGGS (1912) recovery of plants with saturated environment and by irrigating recovery method. The experimental design used was in a completely randomized design with four replications totaling 20 experimental plots. It was verified that the rootstocks Cravo Santa Cruz lemon and Volkamerian lemon were the most resistant in initial conditions of water restriction, evaluated by the method of BRIGGS & SHANTZ (1912), with recording of humidity of 0.0488 and 0.0489 respectively. Under more severe conditions of water restriction, determined by the irrigation method, Volkamerian lemon presented the highest resistance, with a humidity of 0.0371.

Physiological and antioxidant changes in sunflower seeds under water restriction

Abstract: Seed vigor may be determinant for field performance, especially under water restriction conditions. Sunflower is a crop subject to these conditions in the field and, therefore, the aim of this study was to evaluate the physiological and antioxidant changes in sunflower seeds under water restriction. Two lots of sunflower seeds (cv. Hélio 253) with different vigor levels were used. After initial characterization, seeds were placed to germinate under water potentials of 0.0, -0.2, -0.4, -0.6 and -0.8 MPa and evaluated by tests of germination, first germination count, shoot length and primary root length. The activities of the antioxidant enzymes SOD, CAT, POX and APX were also evaluated at 0, 2, 4 and 6 days after sowing. Water restriction led to a decrease in germination and slower seedling growth, regardless of seed vigor level. SOD activity was similar in the two lots, with reduction in activity four days after sowing. CAT activity was affected differently during germination in the two lots, and it was generally higher in the most vigorous lot. In higher vigor seeds, there was lower POX activity in water restriction treatments compared to the control. In general, seeds of lower vigor have lower capacity for activation of antioxidant enzymes, especially peroxidases.

Comportamiento agronómico y fisiológico de maíces nativos del sureste de México


 México es el centro de origen y domesticación del maíz (Zea mays L.), en algunas regiones aún existen poblaciones criollas con potencial para generar variedades mejoradas. El objetivo de este estudio fue evaluar el comportamiento agronómico y fisiológico de doce poblaciones de maíz nativas del sureste de México. El experimento se realizó en Tizimín, Yucatán en el año 2017. Se evaluaron 32 parámetros correspondientes a variables vegetativas, fenológicas, agronómicas y fisiológicas. Los resultados mostraron una diferencia de 75 cm entre las plantas más bajas (Xn-69) y las de porte más alto (CNB), las plantas de la población DZ-252 presentaron mayor follaje (19.1 hojas) y mayor diámetro de tallo (26 mm), las poblaciones más precoces fueron CM y CCB (65.5 y 65.8 días, respectivamente). El 58% de las poblaciones evaluadas superó el rendimiento promedio de la región (4.5 t ha-1). El mayor rendimiento lo obtuvieron las poblaciones CM, Cro, H1 y SP2015 (117.7, 105.8, 111.5 y 109.5 g planta-1, respectivamente). Las poblaciones CM, DZ2015, Cja y Cro tuvieron mayor tasa fotosintética; sin embargo, la mayor eficiencia del uso del agua lo presentaron las poblaciones DZ-252 y XnQroo (8.9 μmol CO2/mmol H2O). La población CM destacó por su rendimiento y precocidad, la DZ-252 podría utilizarse como forraje por la cantidad de biomasa que generó y la XnQroo debería ser estudiada bajo condiciones de restricción hídrica por su eficiencia del uso del agua, estas tres poblaciones deberían incluirse en programas de mejoramiento genético.

Quality Attributes and Fatty Acid, Volatile and Sensory Profiles of "Arbequina" hydroSOStainable Olive Oil.

The use of deficit irrigation techniques on olive orchards is the main trend aiming to optimize water savings while improving functional and sensory characteristics of oils from trees under deficit irrigation techniques. The brand hydroSOStainable has been defined for crops produced under water restriction conditions. HydroSOStainable olive oils obtained under two new regulated deficit irrigation and one sustained deficit irrigation treatments in “Arbequina” olive trees were evaluated by analyzing quality parameters, antioxidant activity, total phenol content, fatty acid profile, volatile compounds, and sensory descriptors. Results showed that some of these irrigation strategies improved the phenol content at “moderate” stress levels, slightly enriched the fatty acid profile (~3.5% increased oleic acid and simultaneously decreased saturated fatty acids), and increased some key volatile compounds and also several key sensory attributes. Therefore, hydroSOStainable olive oil may be more attractive to consumers as it is environmentally friendly, has a higher content of several bioactive compounds, and has improved sensory characteristics as compared to control (fully irrigated) oils.