ABSTRACT Exposing seeds to agents that elicit tolerance to abiotic stress, such as phytohormones and organic acids, during hydration and dehydration cycles can determine their response to later stimuli, e.g. exposure to salt stress. The aim of this study was to evaluate the action of priming cycles with different eliciting agents of salt stress tolerance on seeds of the cowpea varieties Sempre Verde and Pingo de Ouro. The seeds were subjected to the following treatments: 0.0 mM NaCl (control); 100 mM NaCl (salt stress); salt stress + three seed-priming cycles (PC) in water; salt stress + PC in gibberellic acid; salt stress + PC in hydrogen peroxide; salt stress + PC in salicylic acid; salt stress + PC in ascorbic acid. The following variables were analysed: germination, growth, dry weight, salt tolerance index, total soluble sugars, total free amino acids and proline. Salt stress (100 mM NaCl) reduced germination, length and biomass accumulation in the Sempre Verde and Pingo de Ouro varieties. These showed the best response to the priming cycles with gibberellic and salicylic acids, which promoted greater germination potential, length and biomass under a salt stress of 100 mM NaCl, affording greater tolerance via osmotic regulation, especially in the Sempre Verde variety. stimuli eg e g e.g treatments 00 0 0. control (control) 10 stress) seedpriming seed (PC water acid peroxide analysed growth weight index sugars proline (10 potential regulation variety (control 1 (1 (

RESUMO A cultura do sorgo é considerada uma das mais importantes do mundo devido a sua versatilidade de utilização. No entanto, o estresse hídrico pode ser considerado uma ameaça significativa para sua produtividade. A busca por produtos mitigadores do estresse hídrico é uma área de pesquisa crucial na agricultura e na gestão de recursos hídricos. Assim, o objetivo deste trabalho foi avaliar a viabilidade do uso do ácido salicílico como atenuante de estresse hídrico na cultura do sorgo. O experimento foi conduzido em ambiente telado, em delineamento em blocos ao acaso com esquema fatorial 4 × 2, com quatro repetições. Foram avaliados quatro níveis hídricos (40, 60, 80 e 100% da evapotranspiração) e duas concentrações de ácido salicílico (0 e 2,76 g L-1). Foram analisados a altura das plantas, diâmetro do caule, número de folhas, trocas gasosas, pigmentos fotossintéticos e fluorescência da clorofila a. A aplicação de lâminas de irrigação deficitárias reduziu a altura da planta, diâmetro do colmo, número de folhas e clorofila total no sorgo. No entanto, quando essas lâminas foram associadas ao ácido salicílico, foi observado que houve atenuação dos danos, especialmente em relação a clorofila a e b. Além disso, o ácido salicílico quando aplicado isoladamente, contribuiu para redução da temperatura da folha e aumento da eficiência de uso da água. Assim, o ácido salicílico pode ser usado para mitigar os efeitos do estresse salino em plantas de sorgo. utilização entanto produtividade Assim telado 2 repetições 40, 40 (40 60 8 100 evapotranspiração 0 ( 276 76 2,7 L1. L1 L 1 . L-1) caule gasosas planta colmo danos b disso isoladamente água (4 6 10 27 7 L-1 L-

ABSTRACT The sorghum crop is considered one of the most important worldwide due to its versatility. However, water stress can be considered a significant threat to its yield. The search for products that mitigate water stress is a crucial area of research in agriculture and water resources management. Thus, the objective in this study was to evaluate the feasibility of using salicylic acid as a water stress attenuator in sorghum. The experiment was conducted in a screened environment in a randomized block design with a 4 × 2 factorial scheme, with four replicates. Four levels of water (40, 60, 80, and 100% of evapotranspiration) and two concentrations of salicylic acid (0 and 2.76 g L-1) were evaluated. Plant height, stem diameter, number of leaves, gas exchange, photosynthetic pigments, and chlorophyll a fluorescence were analyzed. Application of deficit irrigation depths reduced plant height, stem diameter, number of leaves, and total chlorophyll in sorghum. However, when these depths were associated with salicylic acid, it was observed that the damage was attenuated, especially in chlorophyll a and b. Furthermore, salicylic acid reduced leaf temperature and increased water use efficiency when applied alone. Thus, salicylic acid can be used to mitigate the effects of salt stress on sorghum plants. versatility However yield management Thus scheme replicates 40, 40 (40 60 80 100 evapotranspiration 0 ( 276 76 2.7 L1 L 1 L-1 evaluated height diameter leaves exchange pigments analyzed attenuated b Furthermore alone plants (4 6 8 10 27 7 2. L-

RESUMO Devido às importantes funções do cálcio na fisiologia vegetal, a suplementação deste nutriente pode ser uma estratégia viável para aumentar a tolerância das plantas à salinidade. Assim, o objetivo deste estudo foi avaliar as trocas gasosas e o crescimento de cultivares de rúcula de folhas largas cultivadas em fibra de coco submetidas ao estresse salino. Quatro soluções nutritivas [(S1-solução nutritiva padrão (condutividade elétrica da água - CEa de 0,5 dS m-1; S2- solução nutritiva utilizando água salina com NaCl a 3,5 dS m-1; S3-S2 enriquecida com Ca(NO3)2 a 50%; S4-S2 enriquecido com Ca(NO3)2 a 100%, obtendo valores de 2,3, 5,1, 5,5 e 5,9 dS m-1, para S1, S2, S3 e S4, respectivamente], e duas cultivares de rúcula. (Donatella e Gigante Folha Larga), dispostas em esquema fatorial 2 × 4, com três repetições, foram estudadas. As plantas foram colhidas 40 dias após a semeadura e avaliadas quanto às seguintes variáveis: altura de planta, número de folhas, área foliar, massa fresca total, massa seca total, área foliar específica, suculência foliar, índice relativo de clorofila, condutância estomática, taxa de assimilação de CO2, taxa de transpiração, concentração interna de CO2 e eficiência instantânea do uso da água e eficiência intrínseca de carboxilação. A cultivar Gigante Folha Larga foi mais tolerante à salinidade da solução nutritiva. O uso de solução nutritiva salinizada afetou negativamente o crescimento e a fisiologia da rúcula, mas a adição extra de Ca(NO3)2 reduziu os efeitos nocivos da salinidade. Recomenda-se adição extra de 50% de Ca(NO3)2 na solução nutritiva para reduzir o efeito do estresse salino. vegetal Assim salino S1solução Ssolução S1 S condutividade 05 0 5 0, m1 m 1 m-1 S2 35 3 3, S3S2 SS S3-S CaNO32 CaNO Ca NO3 NO Ca(NO3) 50 S4S2 S4 S4-S 100 100% 23 2,3 51 5,1 55 5, 59 9 m1, 1, respectivamente, respectivamente , respectivamente] Donatella Larga, Larga) 4 repetições estudadas variáveis planta total específica clorofila estomática CO transpiração carboxilação Recomendase Recomenda se m- S3S CaNO3 Ca(NO3 S4S 10 2, Ca(NO

ABSTRACT Due to the important functions of calcium in plant physiology, supplementation of this nutrient may be a viable strategy to increase the tolerance of plants to salinity. Thus, the objective in this study was to evaluate the gas exchange and growth of broad-leaf arugula cultivars cultivated in coconut fiber subjected to salt stress. Four nutrient solutions [(S1 - standard nutrient solution (electrical conductivity of water - ECw of 0.5 dS m-1; S2 - nutrient solution using saline water with NaCl at 3.5 dS m-1; S3 - S2 enriched with Ca(NO3)2 at 50%; S4 - S2 enriched with Ca(NO3)2 at 100%, obtaining values of 2.3, 5.1, 5.5, and 5.9 dS m-1, for S1, S2, S3, and S4, respectively], and two cultivars of arugula (Donatella and Gigante Folha Larga), arranged in a 2 × 4 factorial scheme, with three replicates, were studied. Plants were harvested 40 days after sowing and evaluated for the following variables: plant height, number of leaves, leaf area, total fresh mass, total dry mass, specific leaf area, leaf succulence, relative chlorophyll index, stomatal conductance, CO2 assimilation rate, transpiration rate, internal CO2 concentration, instantaneous water use efficiency, and intrinsic carboxylation efficiency. The cultivar Gigante Folha Larga was more tolerant to salinity of nutrient solution. The use of salinized nutrient solution negatively affected arugula growth and physiology, but the extra addition of Ca(NO3)2 reduced the harmful effects of salinity. Extra addition of 50% of Ca(NO3)2 in the nutrient solution is recommended to reduce the effect of salt stress. physiology Thus broadleaf broad stress S1 S [(S electrical 05 0 5 0. m1 m 1 m-1 35 3 3. CaNO32 CaNO Ca NO3 NO Ca(NO3) 50 100 100% 23 2.3 51 5.1 55 5.5 59 9 5. m1, 1, respectively, respectively , respectively] Donatella Larga, Larga) scheme replicates studied variables height leaves area mass succulence index conductance CO rate concentration efficiency m- CaNO3 Ca(NO3 10 2. Ca(NO

RESUMO No clima semiárido, o crescimento de mudas frutíferas é desafiado pelo estresse hídrico característico da região, o que pode restringir seu desenvolvimento e, consequentemente, afetar a produção. Nesse contexto, o objetivo foi avaliar o efeito do extrato pirolenhoso nas características de troca gasosa, pigmentos fotossintéticos, crescimento e biomassa de pitangueira sob diferentes intensidades de déficit hídrico. O experimento foi conduzido em casa de vegetação utilizando um delineamento em blocos casualizados em um esquema fatorial 3 × 2, com quatro repetições, correspondendo a períodos de déficit hídrico foram de 7 e 14 dias, além do controle (irrigação diária), no substrato sem e com extrato pirolenhoso. As plantas foram avaliadas quanto às características de trocas gasosas foliares, índices de clorofila, crescimento e biomassa seca. A aplicação de extrato pirolenhoso aos 7 dias de déficit hídrico elevou a taxa fotossintética, a eficiência de carboxilação e o índice de qualidade de Dickson das mudas de pitanga em 40,04, 42,85 e 41,51%, respectivamente, em comparação aos 14 dias de déficit hídrico. O extrato pirolenhoso foi efetivo como um atenuante do estresse hídrico nas mudas de pitanga, especialmente durante os primeiros sete dias de exposição ao estresse. Assim, sua aplicação é recomendada como uma medida preventiva e de curto prazo para mitigar tais efeitos nas mudas de pitanga. semiárido região consequentemente produção contexto gasosa fotossintéticos 2 repetições 1 irrigação diária, diária , diária) foliares clorofila seca fotossintética 4004 40 04 40,04 4285 42 85 42,8 4151 41 51 41,51% respectivamente Assim 400 4 0 40,0 428 8 42, 415 5 41,51 40, 41,5 41,

ABSTRACT In the semi-arid climate, the growth of fruit seedlings is challenged by the water stress characteristic of the region, which can restrict their development and, consequently, affect production. In this context, the aim was to assess the effect of pyroligneous extract on gas exchange characteristics, photosynthetic pigments, growth, and biomass of pitanga under different intensities of water deficit. The experiment was conducted using a randomized block design in a 3 × 2 factorial scheme, with four replicates, corresponding to water deficit periods (7 and 14 days) and control (daily irrigation), in substrates with and without pyroligneous extract. The plants were evaluated for gas exchange characteristics, chlorophyll indices, growth, and dry biomass. Application of pyroligneous extract after 7 days of water deficit increased the photosynthetic rate, carboxylation efficiency and Dickson quality index of pitanga seedlings by 40.04, 42.85 and 41.51%, respectively, compared to 14 days of water deficit. Pyroligneous extract was effective as a water stress attenuator in pitanga seedlings, especially during the first seven days of exposure to stress. Therefore, its application is recommended as a preventive and short-term measure to mitigate such effects on pitanga seedlings. semiarid semi arid climate region consequently production context characteristics pigments scheme replicates ( 1 daily irrigation, irrigation , irrigation) indices rate 4004 40 04 40.04 4285 42 85 42.8 4151 41 51 41.51% respectively Therefore shortterm short term 400 4 0 40.0 428 8 42. 415 5 41.51 40. 41.5 41.

RESUMO: A estrutura do sistema radicular do cafeeiro Conilon tem sido aprimorada ao longo dos anos por meio de propagação e estudos genéticos e agronômicos em resposta às demandas por melhorias no desenvolvimento vegetal, na produção e na sobrevivência da espécie. Entende-se que a pesquisa científica desempenha um papel importante na geração de tecnologias e também na segurança das aplicações. Porém, há necessidade de refinar o código gerado para descobrir descobertas e tendências sobre o assunto. Nesse sentido, o presente estudo tem como objetivo realizar uma revisão bibliométrica e análise na base de dados Web of Science (WOS) sobre as principais contribuições de estudos, pesquisadores, organizações e países relevantes nas pesquisas acadêmicas sobre o enraizamento de Coffea canephora. Dados da base de dados WOS publicados entre 1982 e 2021 e sistematizados no software VOSviewer, mostraram um conjunto de 92 artigos, em que a maioria teve origem no Brasil e na França, tendo como principais grupos a Empresa Brasileira de Pesquisa Agropecuária, a Universidade Federal de Viçosa e o CIRAD. O estudo está dividido em quatro áreas: diversidade genética, propagação assexuada, nematologia, tolerância ao estresse hídrico e micropropagação, porém, destaca-se que no contexto das mudanças climáticas e seu impacto na produção e longevidade da cafeicultura brasileira, podemos ver o surgimento de pesquisas focadas no sistema radicular, integrando-o em linhas que exploram e integram temas como risco climático, gestão hídrica, tolerância à seca e irrigação por gotejamento, incluindo reflexões sobre o desempenho da agronomia cafeeira. RESUMO vegetal espécie Entendese Entende se aplicações Porém assunto sentido (WOS pesquisadores canephora 198 202 VOSviewer 9 artigos França Agropecuária CIRAD áreas genética assexuada nematologia micropropagação porém destacase destaca brasileira integrandoo integrando climático hídrica gotejamento cafeeira 19 20 1 2

ABSTRACT: The structure of the root system of the conilon coffee tree has improved over the years through propagation, genetic, and agronomic studies in response to demands for improvements in plant development, production, and survival of the species. Scientific research plays an important role in generating technologies and the security of applications. However, there is a need to refine the content generated to analyze discoveries and trends on the subject. Therefore, the present study conduct a bibliometric review and analysis on the main contributions of relevant studies, researchers, organizations, and countries in academic research on the rooting of Coffea canephora in the Web of Science (WOS) database. Data from the WOS database published between 1982 and 2021 and systematized in the VOSviewer software showed a set of 92 articles, the majority of which originated in Brazil and France, with the main groups being the Brazilian Agricultural Research Corporation, the Federal University of Viçosa, and CIRAD. The study was divided into five areas: genetic diversity, asexual propagation, nematology, tolerance to water stress, and micropropagation. However, in the context of climate changes and its impact on the production and longevity of Brazilian coffee farming, research focused on the root system has increased significantly, integrating it into lines that explore and integrate topics such as climate risk, water management, drought tolerance, and drip irrigation, including reflections on the performance of coffee agronomy. ABSTRACT propagation development species applications However subject Therefore researchers organizations (WOS 198 202 9 articles France Corporation Viçosa CIRAD areas diversity nematology stress micropropagation farming significantly risk management irrigation agronomy 19 20 1 2

RESUMO: Uma das causas de perda de produtividade em lavouras de cana está associada à espécie Diatraea saccharalis, também conhecida por broca da cana. Portanto, este estudo avaliou a viabilidade do uso de sensores hiperespectrais para obter a resposta espectral foliar da cana-de-açúcar em diferentes períodos de infestações, tanto a nível foliar quanto dossel, a fim de diagnosticar antecipadamente os danos da Diatraea saccharalis. O estudo contou com três variedades de cana-de-açúcar: CTC9003BT, CTC4 e RB966928. Em metade das parcelas foi utilizado o inseticida Altacor® para o controle de pragas. As coletas de dados ocorreram nas fases: brotação, perfilhamento, crescimento de colmos e início da maturação. Para avaliar os efeitos da broca na cana foi coletado os dados referentes ao conteúdo relativo de água (CRA), assinatura espectral foliar em laboratório e dossel, índices de vegetação (NDVI e MCARI), produtividade, pureza e ATR (Açúcar Total Recuperável). O maior CRA encontrado foi para a CTC9003BT (60,15%) sem inseticida e 59,0% com inseticida. As faixas espectrais do visível (400-680 nm) e infravermelho próximo (750-1300 nm) identificaram variações espectrais nas plantas com e sem broca. O percentual de broca apresentou correlações altas e negativas entre a produtividade, NDVI e ATR, com coeficientes de -0,68, -0,76 e -0,76, respectivamente. Os índices NDVI e MCARI foram eficazes na detecção de plantas sob estresse, contudo, sua variação é influenciada por múltiplos fatores, sendo difícil associá-los a um único problema (broca). RESUMO saccharalis Portanto canadeaçúcar açúcar infestações dossel CTCBT CTC BT RB966928 RB Altacor pragas fases brotação perfilhamento maturação CRA, , (CRA) MCARI, MCARI) Açúcar Recuperável. Recuperável . Recuperável) 60,15% 6015 60 15 (60,15% 590 59 0 59,0 400680 400 680 (400-68 nm 7501300 750 1300 (750-130 0,68, 068 68 -0,68 0,76 076 76 -0,7 0,76, respectivamente estresse contudo fatores associálos associá los (broca) RB96692 (CRA 60,15 601 6 1 (60,15 5 59, 40068 40 (400-6 750130 75 130 (750-13 0,68 06 -0,6 0,7 07 7 -0, (broca RB9669 60,1 (60,1 4006 4 (400- 75013 13 (750-1 0,6 0, -0 RB966 60, (60, (400 7501 (750- - RB96 (60 (40 (750 RB9 (6 (4 (75 ( (7

ABSTRACT: One of the causes of productivity loss in sugarcane cultivation has been associated with the species Diatraea saccharalis, also known as the sugarcane borer. Therefore, this study evaluated the feasibility of using hyperspectral sensors to obtain the leaf spectral response of sugarcane in different periods of infestation at leaf and canopy levels to diagnose D. saccharalis damage in advance. The study included three varieties of sugarcane: CTC9003BT, CTC4, and RB966928. The insecticide Altacor® was used to control pestsin half of the plots. Data collection occurred at the following stages: sprouting, tillering, stalke longation, and early maturation. Data regarding relative water content (RWC), leaf spectral signature in the laboratory and canopy, vegetation indices (NDVI and MCARI), productivity, purity, and total recoverable sugar (TRS) were collected to evaluate the borer effects on the sugarcane crop. The highest RWC was observed for CTC9003BT (60.15%) without insecticide and 59.0% with insecticide. The visible (400-680 nm) and near-infrared (750-1300 nm) spectral bands identified spectral variations in plants with and without sugarcane borer. The percentage of sugarcane borer showed high and negative correlations between productivity, NDVI, and TRS, with coefficients of -0.68, -0.76, and -0.76, respectively. The NDVI and MCARI indices effectively detect plants under stress, but their variation is influenced by multiple factors, making it difficult to associate them with a single problem (sugarcane borer). ABSTRACT Therefore D advance CTCBT CTC BT CTC4 RB966928 RB Altacor plots stages sprouting tillering longation maturation RWC, , (RWC) MCARI, MCARI) purity TRS (TRS crop 60.15% 6015 60 15 (60.15% 590 59 0 59.0 400680 400 680 (400-68 nm nearinfrared near infrared 7501300 750 1300 (750-130 0.68, 068 68 -0.68 0.76, 076 76 -0.76 respectively stress factors . borer) RB96692 (RWC 60.15 601 6 1 (60.15 5 59. 40068 40 (400-6 750130 75 130 (750-13 0.68 06 -0.6 0.76 07 7 -0.7 RB9669 60.1 (60.1 4006 4 (400- 75013 13 (750-1 0.6 -0. 0.7 RB966 60. (60. (400 7501 (750- 0. -0 RB96 (60 (40 (750 - RB9 (6 (4 (75 ( (7

Abstract Introduction. Heavy metal pollution is a growing problem due to human activities. Plants can remove, destroy, or transform contaminants from soil, water, and air. By using plant growth regulators and chelating agents, heavy metal toxicity can be reduced. Objective. To evaluate the effect of applying a mixture of oligogalacturonides on peroxidase activity and the contents of malondialdehyde, total protein, and chlorophylls in tomato plants (Solanum lycopersicum L.) var. Amalia subjected to high levels of heavy metals. Materials and methods. Soil contaminated with Cu, Cd, and Fe was collected from the Adalberto Vidal White Ceramic Company in Mayabeque, Cuba, in 2020. The experiment was conducted in 7 kg capacity bags using tomato plants, under semi-controlled conditions at the Instituto Nacional de Ciencias Agrícolas (INCA), with a completely randomized experimental design with each treatment having ten replicates. The treatments with the oligogalacturonides (Ogal) were soil application (30 mg kg-1); foliar spray (20 mg L-1), the combination of these application forms, and a control. Peroxidase activity and the contents of malondialdehyde, total protein, and chlorophylls were determined at 35 and 56 days after the plant’s emergence. Results. The effect of Cu, Cd, and Fe on the seedlings was attenuated by all the use of the Ogal mixture variants use, indicating that they have developed adaptation mechanisms to high metal concentrations which allows to withstand abiotic stress. Conclusions. The Ogal mixture attenuated the effect of heavy metals on peroxidase activity, malondialdehyde content, total proteins, and chlorophylls in Amalia tomato plants.

Resumen Introducción. La contaminación por metales pesados es un problema que ha ido en aumento, debido a las actividades antrópicas. Las plantas pueden eliminar, destruir o transformar contaminantes del suelo, agua y aire. Con el empleo de reguladores del crecimiento vegetal y agentes quelantes se puede reducir la toxicidad por metales pesados. Objetivo. Evaluar el efecto de la aplicación de una mezcla de oligogalacturónidos sobre la actividad peroxidasa y los contenidos de malondialdehido, proteinas totales y clorofilas, en plantas de tomate (Solanum lycopersicum L.) var. Amalia sometidas a altos niveles de metales pesados. Materiales y métodos. Se colectó suelo contaminado con Cu, Cd y el Fe, en la Empresa cerámica blanca Adalberto Vidal de Mayabeque, Cuba en el año 2020. El experimento se desarrolló en bolsas de 7 kg de capacidad y se utilizaron plantas de tomate, en condiciones semi controladas en áreas del Instituto Nacional de Ciencias Agrícolas (INCA), con un diseño experimental completamente aleatorizado con siete tratamientos y diez réplicas. Los tratamientos del producto a base de oligogalacturónidos (Ogal) fueron: aplicación al suelo (30 mg kg-1); aspersión foliar (20 mg L-1), la combinación de estas formas de aplicación y un testigo. A los 35 y 56 días de emergidas las plantas, se determinó la actividad peroxidasa y los contenidos de malondialdehido, proteinas totales y clorofilas. Resultados. El efecto que provocan el Cu, Cd y el Fe en las plántulas, fue atenuado por todas las variantes de uso de la mezcla Ogal, por lo que las mismas han desarrollado mecanismos de adaptación ante las altas concentraciones metálicas que le permiten subsistir al estrés abiótico. Conclusiones. La mezcla de Ogal atenuó el efecto que provocan los metales pesados en la actividad peroxidasa, el contenido malondialdehido, proteínas totales y clorofilas en plantas de tomate var. Amalia.

Abstract Introduction. The parameters of physiological response to drought stress are the result of a combination of slow- or fast-acting attributes. Gas exchange variables are classified as fast-acting and their level of occurrence or impact depends on the interaction between factors such as genotype and the duration, intensity, and phenological stage of stress occurrence. Objective. To identify the levels of physiological response exhibited by Solanum phureja under progressive water deficit stress. Materials and methods. The experiment was conducted between 2019 and 2020 under semi-controlled conditions at the Obonuco Research Center of the Corporación Colombiana de Investigación Agropecuaria. Four potato cultivars were planted, with half of the trial was maintained at field capacity and the other half subjected to water deficit stress by withholding irrigation for 15 days, followed by rehydration. Gas exchange variables, chlorophyll content, and photosynthetic efficiency were evaluated every three days. Results. Significant differences were observed, with maximum gas exchange values in control plants showing 16.67 µmol m-2 s-1 photosynthesis rate (A); 0.34 mol m-2 s-1 stomatal conductance (gs); 5.5 mmol m-2 s-1 transpiration (E), and under stress, 1.17 µmol m-2 s-1 (A); 0.013 mol m-2 s-1 (gs); 0.29 mmol m-2 s-1 (E). Chlorophyll content values ranged between 451.7 and 474.69 mg m-2 with and without irrigation, respectively. Conclusions. Stomatic closure was the earliest response to water deficit, and potato plants showed recovery in gas exchange values after rehydration following stress. Finally, three levels of physiological response were identified: mild, moderate, and severe stress, depending on the intensity and duration of stress, which is useful for future studies and the development of irrigation schedules.

Resumen Introducción. Los parámetros de respuesta fisiológica al estrés por sequía son la conjugación de una serie de atributos de acción lenta o rápida. Las variables de intercambio gaseoso son catalogadas como de respuesta rápida, su nivel de aparición o afección dependen de la interacción entre factores como el genotipo y duración, intensidad y etapa fenológica de ocurrencia del estrés. Objetivo. Identificar los niveles de respuesta fisiológica que presenta Solanum phureja bajo el estrés progresivo por déficit hídrico. Materiales y métodos. El experimento se realizó entre 2019 y 2020, bajo condiciones semi-controladas en el Centro de Investigación Obonuco de la Corporación Colombiana de Investigación Agropecuaria. Se sembraron cuatro cultivares de papa, la mitad del ensayo se mantuvo con riego a capacidad de campo y a la otra parte se le suspendió para inducir estrés por déficit hídrico durante 15 días, luego se rehidrataron; se evaluaron variables de intercambio gaseoso, clorofila y eficiencia fotosintética cada tres días. Resultados. Se presentaron diferencias significativas con los valores máximos de intercambio gaseoso en plantas del tratamiento control con 16,67 µmol m-2 s-1 tasa de fotosíntesis (A); 0,34 mol m-2 s-1 conductancia estomática (gs) 5,5 mmol m-2 s-1 transpiración (E) y en estrés 1,17 µmol m-2 s-1 (A); 0,013 mol m-2 s-1 (gs); 0,29 mmol m-2 s-1 (E). En cuanto al contenido de clorofila, se presentaron valores entre 451,7 y 474,69 mg m-2 con riego y sin riego, respectivamente. Conclusiones. El cierre estomático fue la respuesta más temprana al déficit hídrico, además, las plantas de papa presentaron recuperación de los valores de intercambio gaseoso después del suministro de riego posterior al estrés. Finalmente, se identificaron tres niveles de respuesta fisiológica, estrés leve, moderado y severo, según la intensidad y duración del estrés, lo cual es de utilidad para futuros estudios y planteamientos de calendarios de riego.

Abstract Introduction. Corn is one of the oldest known food grains. With climate change and frequent and severe droughts, the water available in the soil will be considerably reduced. Water deficit affects maize crop development to varying degrees, and sensitivity to this stress varies at different development stages. Objective. To identify the phenological stages most sensitive to water deficit in maize. Materials and methods. The experiment was conducted during two growing seasons in 2020 and 2021 in El Ejido, Los Santos province, Panama, under semi-controlled conditions in the greenhouse facilities of the Instituto Coronel Segundo de Villarreal. The commercial corn hybrid ADV-9293 was used and agronomic management was carried out according to the recommendations of the Institute for Agricultural Innovation of Panamá (IDIAP). Plant height, leaf length and width, stem diameter, biomass and yield components, such as number of rows per ear, number of grains per row and 100-grain mass, were determined throughout the crop cycle. Soil moisture was also determined by the gravimetric method. Water deficit at different stages was generated by drought simulation. Results. The grain yields of the control were higher than the different treatments evaluated with 12.83 t ha-1, followed by the treatment with grain filling stress with 10.31 t ha-1. Two periods were determined to be more sensitive to water deficit; these were the stages from 20 to 35 and 40 to 55 days after planting. Water deficit in the different phenological stages of the crop had a negative impact on the relative chlorophyll content. Conclusion. The pre-flowering and flowering stages were more sensitive to water deficiency in maize.

Resumen Introducción. El maíz es uno de los granos alimenticios más antiguos conocido. Con el cambio climático y las sequías severas y frecuentes, se reducirá en gran medida el agua disponible en el suelo. El déficit hídrico afecta en diversos grados el desarrollo del cultivo de maíz y la sensibilidad a este estrés varía en las diferentes etapas de desarrollo. Objetivo. Identificar las etapas fenológicas más sensibles al déficit hídrico en el cultivo de maíz. Materiales y métodos. El experimento se realizó durante dos ciclos en los años 2020 y 2021 en El Ejido, Provincia de Los Santos, Panamá. Se desarrolló bajo condiciones semicontroladas en la casa de cultivo del Instituto Coronel Segundo de Villarreal. Se utilizó el híbrido de maíz comercial ADV-9293. El manejo agronómico se realizó según las recomendaciones del Instituto de Innovación Agropecuaria de Panamá (IDIAP). Durante todo el ciclo del cultivo, se determinaron las variables altura de planta, largo y ancho de hojas, diámetro del tallo, biomasa y los componentes del rendimiento como número de hileras por mazorca, número de granos por hilera y peso de cien granos. También, se determinó la humedad del suelo por el método gravimétrico. El déficit hídrico en distintas etapas se generó a través de la simulación de sequía. Resultados. El rendimiento de grano del testigo superó los diferentes tratamientos evaluados con 12,83 t ha-1, seguido por el tratamiento con estrés en el llenado de grano con 10,31 t ha-1. Se determinaron dos períodos más sensibles al déficit hídrico; los cuales son las etapas comprendidas desde los 20 a 35 y 40 a 55 dds. El déficit hídrico, durante las diferentes etapas fenológicas del cultivo, tuvo un impacto negativo en el contenido relativo de clorofilas. Conclusión. Las etapas de prefloración y floración resultaron más sensibles a la deficiencia hídrica en el cultivo del maíz.

Summary: Currently, agricultural activity is constantly threatened by the effects of climate change and radical expression of environmental factors as irregular rainfall distribution responsible for water availability and deficit. These factors generate water stress in productive systems, whose negative effect is reflected on morphological, physiological and biochemical aspects of vegetative growth. The use of biostimulants arises as a strategy to counteract this impact, improving crop efficiency in the use of resources and generating responses, as metabolite production, among other substances that mitigate the effects of oxidative stress. In this context, waxes, hydrogen peroxide (H2O2), salicylic acid (SA) and ALGAENZIMSMR were used on raspberry plants subjected to moderate water stress (-0. 8 MPa) to evaluate the fruit response in aspects of vegetative growth, physiological and biochemical quality. For the establishment, a completely randomized design was used with 5 treatments: Green Cover as 5 mL L-1, H2O2 10-4 M, salicylic acid 0.27 mM, ALGAENZIMSMR 7.5 mL L-1 and the control with 50% recovery of the transpired volume as well as water potential similar to the rest of plants and 4 replicates. The results showed that waxes, SA and algal extract increased the photosynthetic rate; the four treatments increased root length; waxes increased root height; and H2O2 increased root biomass. Compared to the control, higher levels of vitamin C and anthocyanins were produced in fruits - a very important aspect due to the functionality of these compounds in human health. Therefore, the use of these biostimulants are a very useful tool for crop management in environments with water restriction.

Resumen: En la actualidad la actividad agrícola se ve amenazada constantemente por los efectos del cambio climático y la expresión radical de los factores ambientales, como la irregularidad en la distribución pluvial responsable de la disponibilidad del agua y déficit, que genera estrés hídrico en los sistemas productivos, cuyo efecto negativo se refleja en aspectos de crecimiento vegetativo, morfológicos, fisiológicos y bioquímicos. El uso de bioestimulantes surge como estrategia para contrarrestar este impacto, mejorando la eficiencia de los cultivos en el uso de los recursos y generar respuestas, como la producción de metabolitos entre otras sustancias, que mitigan los efectos del estrés oxidativo. Bajo este contexto se planteó el uso de ceras, peróxido de hidrogeno (H2O2), ácido salicílico (AS) y algaenzims, sobre plantas de frambuesa sometidas a estrés hídrico moderado (-0.8 MPa) con el objetivo de evaluar la respuesta en aspectos de crecimiento vegetativo, fisiológicos y calidad bioquímica de frutos, para el establecimiento se empleó un diseño completamente al azar con 5 tratamientos: greencover as® 5 mL L-1, H2O2 10-4 M, ácido salicílico 0.27 mM, algaenzims® 7.5 mL L-1 y el control con recuperación del 50% del volumen transpirado y con potencial hídrico similar al resto de plantas y 4 repeticiones. Como resultados se obtuvo que las ceras, AS y el extracto de algas incrementaron la tasa fotosintética, los cuatro tratamientos aumentaron la longitud de raíces, las ceras la altura, y el H2O2 la biomasa de raíz. Por otro lado, en comparación con el control, se produjeron mayores niveles de vitamina C y antocianinas en frutos, un aspecto muy importante por la funcionalidad de estos compuestos en la salud humana. Por lo tanto, el uso de estos bioestimulantes se puede visualizar como una herramienta de gran utilidad para el manejo de cultivos en ambientes con restricción de agua.

Summary: In recent decades, water scarcity has increased considerably in Cuauhtémoc, Chihuahua - the most important apple-growing region of Mexico. Thus, the objective of this research is focused on evaluating growth and development responses in apple rootstocks graf ted with Golden Delicious subjected to four drought cycles, comparing them with the continuous irrigation treatment. Ten rootstocks were evaluated (B.9, M.9Nic29, G.41, G.202, G.890, G.210, G.30, M.7, MM.111 and MM.109) used in the commercial apple orchards in the area, where all the rootstocks were obtained during the 2020 growing season. The planting was carried out in 20-L pots in March 2020 and a substrate composed of compost, soil and sand was used in a ratio of 1:1:1. The recorded variables measured were moisture percentage in the soil, the leading branch growth, leaf water potential, total biomass, and ef ficient water use. The rootstocks B.9 and M.9 Nic29 showed good results in most of the variables studied. Rootstocks with good recovery of leaf water potential af ter recovery irrigation were found. These rootstocks were; B.9, M.9Nic29, MM.111 and G.210. The total biomass was statistically the same in G.30, G.41, MM.111, MM.109, G.202 and B.9. In conclusion, rootstocks tolerate a certain degree of drought and can contribute to improving water use, highlighting B.9.

Resumen: La escasez de agua en la región manzanera más importante de México; Cuauhtémoc, Chihuahua, se ha incrementado considerablemente en las últimas décadas. El objetivo de esta investigación se concentró en evaluar la respuesta en crecimiento y desarrollo de portainjertos de manzano injertados con Golden Delicious, sometidos a cuatro ciclos de sequía, comparándolos con el tratamiento de riego continuo. Se evaluaron 10 portainjertos (B.9, M.9Nic29, G.41, G.202, G.890, G.210, G.30, M.7, MM.111 y MM.109), los cuales son utilizados en las huertas comerciales de manzano de la zona de Cuauhtémoc. Todos los portainjertos se obtuvieron de viveros comerciales durante la estación de crecimiento 2019. La plantación se realizó en macetas de 20 L en el mes de marzo de 2020 y se utilizó un sustrato compuesto por composta, suelo y arena en proporción 1:1:1. Las variables registradas fueron; porcentaje de humedad en el suelo, crecimiento de la rama líder, potencial hídrico de la hoja, biomasa total, y uso eficiente del agua. Los portainjertos B.9 y M.9Nic29 mostraron buenos resultados en la mayoría de las variables estudiadas. Los portainjertos B.9, M.9Nic29, MM.111 y G.210 mostraron buena recuperación del potencial hídrico de la hoja después del riego de recuperación. La biomasa total fue estadísticamente igual en G.30, G.41, MM.111, MM.109, G.202 y B.9. Se concluye que existen portainjertos que toleran cierto grado de sequía y que pueden contribuir a mejorar el uso del agua, destacando B.9.

Abstract Introduction: Passiflora tripartita var. mollissima (banana passionfruit) is one of the most promising exotic tropical fruits from the diversity of the Passifloraceae family in South America, because of its organoleptic properties and antioxidant activity. Objective: To evaluate the physiological and anatomical responses of banana passionfruit plants under water deficit to better understand the mechanisms that mitigate this stress and affect the production of crops subject to climate change and global warming. Methods: Three-month-old seedlings of banana passionfruit were subjected to a soil water deficit through an irrigation reduction at 70 % for 49 days under greenhouse conditions. Morphology (leaf area, height, and number of leaves) and physiological (stomatal conductance, Fv/Fm, total chlorophyll content) measurements were made through time, and after the irrigation treatments were measured biomass parameters and anatomical foliar traits. Results: The plants experienced a decrease in height, leaf area, number of leaves, leaf area index, and relative water content, that are common responses in plants subjected to reduced irrigation. Additionally, the plants exhibited certain mechanisms that can be attributed to water deficit tolerance such as higher root:shoot ratio, stomatal closing, an increase in stomatal density, a reduction in mesophyll tissue thickness, and a decrease in the number of vessels and its diameter as they enable the banana passionfruit to reduce water loss and decrease the probability of cavitation in xylem vessels. Conclusions: banana passionfruit plants could implement strategies against water scarcity, allowing them to survive and endure challenging environmental conditions.

Resumen Introducción: Passiflora tripartita var. mollissima (banana passionfruit - curuba) es una de las frutas tropicales exóticas de la diversidad de la familia Passifloraceae en Sudamérica, promisoria por sus propiedades organolépticas y actividad antioxidante. Objetivo: Evaluar las respuestas fisiológicas y anatómicas de la curuba bajo déficit hídrico con el fin de comprender mejor los mecanismos que mitigan este estrés y afectan la producción de sus cultivos, que están sujetos al cambio climático y al calentamiento global. Métodos: Plántulas de 3 meses de edad se sometieron a un déficit hídrico mediante una reducción del riego al 70 % durante 49 días en condiciones de invernadero. Se realizaron mediciones morfológicas (área foliar, altura y número de hojas) y fisiológicas (conductancia estomática, Fv/Fm, contenido de clorofilas) a lo largo del tiempo, y transcurridos los tratamientos de irrigación se midieron parámetros de biomasa, además de rasgos anatómicos foliares. Resultados: Las plantas experimentaron una disminución en la altura, área foliar, número de hojas, índice de área foliar y contenido relativo de agua, respuestas comunes en plantas sometidas a una irrigación reducida. Adicionalmente, las plantas exhibieron ciertos mecanismos que pueden atribuirse a la tolerancia al déficit hídrico tales como una mayor relación raíz:vástago, cierre de estomas, un aumento en la densidad estomática, una reducción en el grosor del tejido del mesófilo y una disminución en el número de vasos del xilema y su diámetro; pues le permiten a la curuba disminuir la pérdida de agua y reducir la probabilidad de cavitación en los vasos del xilema. Conclusiones: Las plantas de la curuba tienen la capacidad de implementar estrategias de mitigación frente al déficit hídrico, lo que les permite sobrevivir y soportar condiciones ambientales desafiantes.

ABSTRACT Potassium is a nutrient with the potential to increase plant tolerance to salt stress. The aim of this study was to evaluate the production and quality of kale subjected to salt stress and potassium concentrations in a protected environment. The experimental design was in split plots, with plots composed of five nutrient solutions (control treatment, S1 - standard nutrient solution prepared in low-salinity water, 0.5 dS m-1 (500 mg L-1 of KNO3), and four nutrient solutions prepared in brackish waters (3.5 dS m-1) containing four concentrations of KNO3 (S2 - 500 mg L-1, S3 - 625 mg L-1, S4 - 750 mg L-1, S5 - 1,000 mg L-1), and subplots represented by two leaf kale cultivars (Manteiga and Manteiga da Geórgia). Leaf production variables and post-harvest physical and chemical qualities were evaluated. The saline nutrient solution with the addition of NaCl (S2) reduced production but did not reduce the post-harvest quality of kale. The extra addition of KNO3 at 25% (S3) was efficient in reducing the deleterious effects of salt stress on the variables leaf length, leaf area, leaf production, and number of bunches. The cv. Manteiga da Geórgia was more tolerant to salt stress than the cv. Manteiga. environment control treatment S lowsalinity low salinity water 05 0 5 0. m1 m 1 m- (50 L1 L L- KNO3, KNO , KNO3) 3.5 35 3 (3. S2 (S 50 L1, 1, 62 75 1000 000 1,00 L-1) Geórgia. . Geórgia) postharvest post harvest evaluated 25 (S3 length area bunches cv (5 3. (3 6 7 100 00 1,0 2 ( 10

RESUMO O potássio é um nutriente com potencial para aumentar a tolerância das plantas ao estresse salino. O objetivo deste estudo foi avaliar a produção e a qualidade da couve submetida ao estresse salino e às concentrações de potássio em ambiente protegido. O delineamento experimental adotado foi em parcela subdivididas, sendo as parcelas compostas por cinco soluções nutritivas (tratamento controle, S1 - solução nutritiva padrão usando água de baixa salinidade, 0,5 dS m-1 (500 mg L-1 de KNO3), e quatro soluções nutritivas preparadas em águas salobras (3,5 dS m-1) contendo quatro concentrações de KNO3 (S2 - 500 mg L-1, S3 - 625 mg L-1, S4 - 750 mg L-1, S5 - 1.000 mg L-1). As subparcelas foram representadas por duas cultivares de couve folha (Manteiga e Manteiga da Geórgia). Foram avaliadas as variáveis de produção de folhas e qualidades físicas e químicas pós-colheita. A solução nutritiva salinizada com adição de NaCl (S2) reduziu a produção, mas não reduziu a qualidade pós-colheita da couve folha. A adição extra de KNO3 em 25% (S3) foi eficiente para reduzir o efeito deletério do estresse salino sobre as variáveis comprimento de folha, área foliar, produção e número de maços. A cv. Manteiga da Geórgia se mostrou mais tolerante ao estresse salino que a cv. Manteiga. protegido subdivididas tratamento controle S salinidade 05 0 5 0, m1 m 1 m- (50 L1 L L- KNO3, KNO , KNO3) 3,5 35 3 (3, S2 (S 50 L1, 1, 62 75 1000 000 1.00 L1. . L-1) Geórgia. Geórgia) póscolheita. póscolheita pós colheita. colheita 25 (S3 foliar maços cv (5 3, (3 6 7 100 00 1.0 2 ( 10 1.

ABSTRACT Soil salinization, a rising issue globally, is a negative effect of the ever-changing climate, which has drawn attention to, and exacerbated problems related to soil degradation and the decline in wetland rice (Oryza sativa L.) production, leading to an unstable national economy. The use of rhizosphere inhabiting microorganisms (plant growth-promoting rhizobacteria, PGPR) is a viable method for boosting agricultural production on saline soils and reduce salt stress in rice crops. The objective of this study was to support the development of rice under salt stress by using a consortium of bacterial strains. ‘Pokkali’ rice plants inoculated with single Bacillus tequilensis and B. aryabhattai isolates were compared with consortium and non-inoculated plants while salinity was increased and by irrigation with tap water (control), 30 mM (5 dS m-1) and 60 mM (10 dS m-1) NaCl. The present study exhibited that inoculation of a mixed inoculum at 5 dS m-1 resulted in significantly higher dry weight of the shoots and roots of seedlings (9.29 and 1.24 g, respectively) which was due to the increased SPAD value, proline content (7.55 µmol g-1 FW), and antioxidant enzyme activity in the inoculated plants. The higher accumulation of osmoprotectants such as proline supported Na+ ion reduction and antioxidant enzymes such as ascorbate peroxidase and reduced polyphenol oxidase content protect against higher cellular damage, eventually leading to increase plant growth performance in saline soil. This study demonstrates some positive effects of the locally isolated salt tolerant consortium PGPR strains on the growth of rice plants under salt stress conditions.

ABSTRACT Maize (Zea mays L.) is highly sensitive to salt stress, which poses a threat to its production, especially with predicted increases in salinity due to climate change. Enhancing salt tolerance in maize is critical to mitigating these adverse effects, sustaining its production, and ensuring global food security. This study aimed to evaluate the effects of exogenously applied lipoic acid or Si, alone or in integration with soil application of vermicompost-tea on physio-biochemical components, antioxidant defense systems, growth, and yield of maize plants exposed to salt stress. The application of vermicompost-tea was carried out as a soil treatment incorporated into irrigation water at a concentration of 200 L ha-1, and administered in three equal doses in irrigation water within the last 10 min of drip irrigation. Silicon was applied at a rate of 6 mM using potassium silicate and lipoic acid was applied at 0.1 mM. Silicon and lipoic acid were applied three times at 25, 40, and 55 d after planting. The results indicated that the integrative application of soil-based vermicompost-tea with exogenously applied Si or lipoic acid significantly enhanced all studied parameters. Specifically, the combination of Si with vermicompost-tea exhibited the highest improvement percentage compared to untreated control in chlorophyll a (60.3%), chlorophyll b (72.7%), carotenoids (69.9%), net photosynthetic rate (111%), transpiration rate (134%), stomatal conductance (129.5%), relative water content (28.4%), membrane stability index (44.3%), N (33.4%), P (71.9%), K (39.7%), Ca (89.9%), K/Na (81.2%), total soluble sugars (63.7%), proline (60.1%), ascorbate (44.4%), glutathione (83.5%), and α-tocopherol (72.1%). These positive effects were reflected in enhancing yield traits under salt-affected soil conditions by enhancing plant height (25.1%), number of grains per row (43.3%), number of rows per ear (26.7%), 1000‐grain weight (25.9%), grain yield (45.4%), and biological yield (42.8%) compared to untreated control.