RESUMO: O uso de métodos não destrutivos e de baixo custo para determinação de área foliar tem ganhado importantes aplicações. Os objetivos da pesquisa foram (i) propor um método não destrutivo para estimar a área foliar da cultura da mamona e (ii) construir equações que estimem com precisão e rapidez a área foliar da espécie. Foram coletadas mil folhas sadias e expandidas de cinco cultivares de mamona (New Zealand Purple, Sipeal, Carmencita, Amarelo de Irecê e IAC-80), sendo coletadas 200 folhas de cada uma. O comprimento máximo, largura máxima e área foliar foram calculados para cada folha. Foi calculado o produto entre comprimento e largura (LW). Foram realizados testes com diferentes modelos de regressão linear e não linear entre área foliar e dimensões lineares das folhas de cada cultivar. Os modelos utilizados foram linear, linear sem intercepto e potência. Os critérios para escolha dos melhores modelos para estimar a área foliar da mamona foram maior coeficiente de determinação, maior coeficiente de correlação linear de Pearson, menor critério de informação de Akaike, maior índice de concordância de Willmott e menor raiz do erro quadrático médio. As equações que apresentaram melhores critérios para estimativa da área foliar das cultivares de mamona foram aquelas que utilizaram o produto entre comprimento e largura, em comparação às equações que utilizaram apenas uma dimensão foliar. O modelo ŷ = 0,439 × LW pode ser utilizado para estimar com precisão e rapidez a área foliar da mamona por meio de medidas lineares das folhas, utilizando o produto entre comprimento e largura (LW), independente da cultivar escolhida. RESUMO aplicações i (i ii (ii espécie New Purple Sipeal Carmencita IAC80, IAC80 IAC 80 , IAC-80) 20 máximo folha LW. . (LW) potência Pearson Akaike médio 0439 0 439 0,43 LW, escolhida IAC8 8 IAC-80 2 (LW 043 43 0,4 IAC-8 04 4 0, IAC-

ABSTRACT: Using non-destructive and low-cost methods to determine leaf area has gained important applications. The research objectives were (i) to propose a non-destructive method to estimate the leaf area of castor bean crops and (ii) to build equations that accurately and quickly estimate the leaf area of specie. One thousand healthy and expanded leaves of five castor bean cultivars (New Zealand Purple, Sipeal, Carmencita, Amarelo de Irecê, and IAC-80) were collected, and 200 leaves were collected from each. The maximum length, maximum width, and leaf area were calculated for each leaf. The product between length and width (LW) were calculated. We performed tests with different linear and non-linear regression models between leaf area and linear leaf dimensions of each cultivar. The models used were linear, linear without intercept, and power. The criteria for choosing the best models to estimate the leaf area of castor beans were a higher coefficient of determination, more elevated Pearson’s linear correlation coefficient, lower Akaike information criterion, higher Willmott agreement index, and smallest root mean square error. The equations that presented the best criteria for estimating the leaf area of castor bean cultivars were those that used the product between length and width, compared to equations that used only one leaf dimension. The model ŷ = 0.439 × LW can be used to accurately and quickly estimate the castor bean leaf area through linear measurements of the leaves, using the product between length and width (LW), regardless of the cultivar chosen. ABSTRACT nondestructive non destructive lowcost low cost applications i (i ii (ii specie New Purple Sipeal Carmencita Irecê IAC80 IAC 80 IAC-80 20 (LW nonlinear intercept power determination Pearsons Pearson s criterion index error dimension 0439 0 439 0.43 LW, , chosen IAC8 8 IAC-8 2 043 43 0.4 IAC- 04 4 0.

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 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 Introduction. The main control measure for brown spot (BS) caused by Septoria glycines is through the application of foliar fungicide. However, the management of the disease could be accomplished through cultural and genetic practices. Objective. To analyze the evolution of BS in soybean under different production systems. Materials and methods. This study was conducted for two consecutive years (2020 and 2022), in Pergamino, Buenos Aires, using the soybean cultivar DM46i20. The management variables studied were cover crops (CC), rotations (Rt), and timing of foliar fungicide application (MAFF). The evaluated pathometric variable was the area under the progress curve of plant height with symptoms (ABCPAPS), and the quantitative physiology variable was grain yield (R) in kg/ha. Results. Agronomic management practices had a significant effect (p≤0.05) on R and ABCPAPS. CC and MAFF were independent variables and showed a significant response (p<0.0001) on R. On the other hand, there was a significant triple interaction (p<0.0001) among CC, Rt, and MAFF for ABCPAPS, and therefore, the data were explained based on this relationship. Conclusions. The implementation of cover crops, crop rotations, and foliar fungicide significantly reduced (p≤0.05) the evolution of BS in soybean cultivation. There was a significant negative correlation (p≤0.05) between soybean yield and the area under the progress curve of the plant height with BS symptoms.

Resumen Introducción. La principal medida de control de la mancha marrón (MM) causada por Septoria glycines, se realiza mediante la aplicación de fungicida foliar, sin embargo, el manejo de la enfermedad podría realizarse con prácticas de manejo cultural y genético. Objetivo. Analizar la evolución de la MM de la soja en diferentes sistemas de producción. Materiales y métodos. Este estudio se llevó a cabo durante dos años consecutivos (2020 y 2022), en la localidad de Pergamino, Buenos Aires, sobre un cultivar de soja DM46i20. Las variables de manejo fueron cultivos de cobertura (CC), rotaciones (Rt), momento de aplicación del fungicida foliar (MAFF). La variable patométrica evaluada fue el área bajo la curva de progreso de la altura de la planta con síntomas (ABCPAPS) y como variable cuantitativa fisiología sobre el cultivo el rendimiento (R) en granos en kg/ha. Resultados. Las prácticas de manejo agronómico tuvieron un efecto significativo (p≤0,05) sobre el R y el ABCPAPS. Las variables CC y MAFF fueron independientes y presentaron una repuesta significativa (p<0,0001) sobre el R. En cambio, hubo una triple interacción significativa (p<0,0001) entre los CC, las Rt y el MAFF para el ABCPAPS y, por lo tanto, los datos fueron explicados con base en esta relación. Conclusiones. La implementación de cultivos de cobertura, de rotaciones de cultivo y de fungicida foliar, redujeron significativamente (p≤0,05) la evolución de la MM en el cultivo de soja. Hubo una correlación negativa y significativa (p≤0,05) entre el rendimiento en soja y el área bajo la curva de progreso de la altura de la planta con síntomas de la MM.

Abstract Introduction. Defoliation studies on sugarcane in Mexico are scarce, and it is unknown at what age of the plant and in which season of the year it should be carried out. Objective. To evaluate the effect of artificial defoliation in sugarcane at different stages of growth and its response on quality and yield parameters. Materials and methods. The experiment was conducted during the 2020-2021 harvest between the months of April and May, in a plot located in a ratoon of the cultivar COLPOSCTMEX 06-039, within the supply area of the Ingenio Presidente Benito Juárez in the Chontalpa region, Tabasco. A completely randomized block design was used, where the defoliation treatments consisted of removing the entire leaves of the stem until leaving the +5 leaf (H5). Defoliation treatments were applied at 8, 9, and 10 months of crop age, plus a control without defoliation, with five replicates per treatment. Growth parameters evaluated were plant height and diameter, number of stalks, and leaf area index (IAF) and normalized difference vegetation index (NDVI). At harvest, °Brix and sugarcane yields of sugarcane were measured. Results. It was found that growth and quality parameters were reduced by total defoliation treatments. Treatment 2 showed the highest values of plant height and diameter, lower NDVI, and stalk yield at harvest, and defoliation affected the IAF. °Brix were not affected by different defoliation treatments. Conclusion. Defoliation at nine months of age increased agricultural yield and did not affect juice quality.

Resumen Introducción. Estudios de defoliación en caña de azúcar en México son escasos, se desconoce a qué edad de la planta y en qué época del año se deben realizar. Objetivo. Evaluar el efecto de la defoliación artificial en caña de azúcar en diferentes etapas de cultivo y su respuesta sobre parámetros de calidad y rendimiento. Materiales y métodos. El experimento se llevó a cabo en la zafra 2020-2021 entre los meses de abril y mayo, en una parcela ubicada en una soca del cultivar COLPOSCTMEX 06-039, dentro de la zona de abastecimiento del Ingenio Presidente Benito Juárez de la Chontalpa, Tabasco. Se utilizó un diseño experimental de bloques completamente al azar, donde los tratamientos de defoliación consistieron en eliminar las hojas completas del tallo hasta dejar la hoja +5 (H5). Los tratamientos de defoliación se aplicaron a los 8, 9 y 10 meses de edad del cultivo, más un testigo sin defoliación, con cinco repeticiones por tratamiento. Los parámetros de crecimiento evaluados fueron altura y diámetro de planta, número de tallos e índices de área foliar (IAF) y de vegetación de las diferencias normalizada (NDVI). Al momento de la cosecha se midieron los °Brix y los rendimientos agrícolas de la caña de azúcar. Resultados. Se encontró que los parámetros de crecimiento y calidad fueron disminuidos por los tratamientos de defoliación total. El tratamiento 2 mostró los mayores valores de altura y diámetro de planta, menor NDVI y rendimiento de tallos al momento de la cosecha y la defoliación afectó el IAF. Los °Brix no se vieron afectados por los diferentes tratamientos de defoliación. Conclusión. La defoliación a los nueve meses de edad aumentó el rendimiento agrícola y no afectó la calidad de los jugos.

Abstract Introduction. In Ecuador, there are few studies on the use of microbial inoculants for the sustainable production common bean (Phaseolus vulgaris L.). Objective. To evaluate the effect of inoculation with plant growth-promoting rhizobacteria (PGPR) on productive and economic variables of P. vulgaris. Materials and methods. The research was carried out at the La Argelia Experimental Station in Loja, Ecuador, from February to July 2022. Using loamy soil, the common bean cultivar “Mantequilla” was employed in a randomized complete block design with seven treatments and four replications each. The treatments were: T1) absolute control, T2) Bacillus subtilis, T3) Rhizobium leguminosarum bv. viciae, T4) Pseudomonas fluorescens + B. subtilis, T5) R. leguminosarum bv. viciae + B. subtilis, T6) R. leguminosarum bv. viciae + P. fluorescens + B. subtilis, and T7) chemical fertilization. The effect of the treatments on growth, development, and yield components in the evaluated cultivar was assessed. Additionally, an economic analysis of the application of beneficial microorganisms versus chemical fertilization was conducted. Results. Treatment T6 (R. leguminosarum bv. viciae + P. fluorescens + B. subtilis) shortened the phenological phases (days), promoted a higher number of nodules, emergence percentage, plant height, leaf area, number of pods per plant, weight of 100 seeds, nitrogen content, and agricultural yield without statistical differences (p<0.05) compared to chemical fertilization (T7). The economic analysis showed that T6 generated higher income and greater profitability compared to chemical fertilization. Conclusion. Inoculation with beneficial microorganisms positively affected the productive and economic variables of common beans and can be a valid alternative to the conventional use of chemical fertilizers.

Resumen Introducción. En Ecuador, existen pocos estudios sobre la utilización de inoculantes microbianos para la producción sostenible del fríjol común (Phaseolus vulgaris L.). Objetivo. Evaluar el efecto de la inoculación con rizobacterias promotoras del crecimiento vegetal (PGPR) en variables productivas y económicas de P. vulgaris . Materiales y métodos. La investigación se desarrolló en la Estación Experimental La Argelia, Loja, Ecuador, durante el periodo de febrero a julio de 2022. En un suelo de textura Franca, se empleó el cultivar de fríjol común Mantequilla bajo un diseño en bloques completos al azar con siete tratamientos y cuatro repeticiones de cada uno. Los tratamientos fueron: T1) control absoluto, T2) Bacillus subtilis, T3) Rhizobium leguminosarum bv. viciae, T4) Pseudomonas fluorescens + B. subtilis, T5) R. leguminosarum bv. viciae + B. subtilis, T6) R. leguminosarum bv. viciae + P. fluorescens + B. subtilis, y T7) fertilización química. Se evaluó el efecto de los tratamientos sobre variables de crecimiento, desarrollo y componentes de rendimiento en el cultivar evaluado. Además, se realizó un análisis económico de la aplicación de los microorganismos benéficos frente a la fertilización química. Resultados. El tratamiento: R. leguminosarum bv. viciae + P. fluorescens + B. subtilis (T6) acortó las fases fenológicas (días), promovió un mayor número de nódulos, porcentaje de emergencia, altura de la planta, área foliar, número de vainas por planta, peso de 100 semillas, contenido de nitrógeno y rendimiento agrícola sin diferencias estadísticas (p<0,05) con respecto a la fertilización química (T7). Mediante el análisis económico se estableció que el T6 generó mayores ingresos, y una mayor rentabilidad frente a la fertilización química. Conclusión. La inoculación con microorganismos benéficos afectó positivamente las variables productivas y económicas de frijol común y puede ser una alternativa válida al uso convencional de fertilizantes químicos.

Summary: Plant growth, higher yield and fruit quality are positive ef fects due to the absorption of silicon (Si) and chlorine (Cl), which contributes to mitigating stress due to biotic or abiotic factors and recovering plant growth. The objective of this research was to know what the ef fect of Si or Cl does on morphometric variables, production quality and yield of the cucumber crop. A complete randomized block design was applied, four repetitions and ten treatments in seedlings: six doses of 20, 30 and 50 mg L-1 of Si or Cl, three doses with the volume:volume (v:v) ratio of 20 :20, 30:30 and 50:50 mg L-1 Si:Cl, plus the control. In plants transplanted in soil, already with five true leaves, there were nine treatments: six doses of 20, 30 and 50 mg L-1 of Si or Cl, two with the v:v ratio of 20:20 and 30:30 mg L-1 Si:Cl, and the witness. In pickle cucumber seedlings, the high dose of Cl was more ef fective in increasing leaf greenness and stem length; leaf size was greater in seedlings with the high dose of Si; while low doses of Cl or Si caused greater dry weight of roots. In the ˈModanˈ cultivar, the greenness did not change, the stem length was greater with the intermediate dose of Si, while the size of leaves was better expressed in plants with the lowest dose of Si. So perhaps the greater number of roots, the chlorophyll content and the leaf area influenced the higher yield to be expressed where Si or Cl was fertilized, as well as the firmness, TSS and °Brix of the fruits to improve.

Resumen: El crecimiento de plantas, mayor rendimiento y calidad de frutos, son efectos positivos debido a la absorción de silicio (Si) y cloro (Cl), que contribuye a mitigar el estrés por factores bióticos o abióticos y recuperar el crecimiento de las plantas. El objetivo de la presente investigación fue conocer el efecto que producen las dosis de Si o Cl en variables morfométricas, calidad de producción y rendimiento del cultivo de pepino. Se aplicó un diseño de bloques completos al azar, cuatro repeticiones y diez tratamientos en plántulas: seis dosis de 20, 30 y 50 mg L-1 de Si o Cl, tres dosis con la relación volumen:volumen (v:v) de 20:20, 30:30 y 50:50 mg L-1 Si:Cl, más el testigo. En plantas trasplantadas en suelo, ya con cinco hojas verdaderas, los tratamientos fueron nueve: seis dosis de 20, 30 y 50 mg L-1 de Si o Cl, dos con la relación v:v de 20:20 y 30:30 mg L-1 Si:Cl, y el testigo. En plántulas de pepino ˈpickleˈ, la dosis alta de Cl fue más eficaz para incrementar el verdor de hojas y longitud del tallo; el tamaño de hojas fue superior en plántulas con la dosis alta de Si; mientras que las bajas dosis de Cl o Si ocasionaron mayor peso seco de raíces. En el cultivar ˈModanˈ el verdor no varió, la longitud del tallo fue superior con la dosis intermedia de Si, mientras que el tamaño de hojas se expresó mejor en plantas con la menor dosis de Si. Así que quizás la mayor cantidad de raíces, el contenido de clorofila y el área foliar influyeron para que el rendimiento más alto se expresara donde se fertilizó con Si o Cl, así como para que mejoraran la firmeza, SST y °Brix de los frutos.

Summary: The fraction of vegetation cover (FVC) and the Leaf Area Index (LAI) are biophysical variables closely related to the evapotranspiration rate of crops and their biomass production. Despite their importance, they are usually not measured directly due to their time-consuming and costly nature; however, they can be estimated on a large scale and near-real-time using spectral information captured in satellite images, although this requires prior validation at the field level. Simple linear regression models were developed and validated using 13 vegetation indices (VI) related to LAI and FCV in alfalfa (Medicago sativa). Three spectral information sources were used: (i) reflectance to derive the VI; (ii) digital photographs processed with the Canopeo application to estimate FVC; and (iii) direct LAI measurements using a ceptometer. Six field samples were taken between March and June, 2020 in four alfalfa plots located in Palmar de Bravo, Puebla, Mexico. To evaluate each VI, the determination coefficient (R2) and the root mean square error (RMSE) were used. We found that the most suitable VI for estimating FVC was the VIgreen (Green Vegetation Index, R2 =0.987 and RMSE = 0.093). For the LAI, the VI that performed best was the NDVI (Normalized Difference Vegetation Index, R2 = 0.935 and RMSE = 0.746). The results showed the suitability and practical utility of spectral information for estimating biophysical variables in alfalfa cultivation and their monitoring.

Resumen: La fracción de cobertura vegetal (FCV) y el índice de área foliar (IAF) son variables biofísicas relacionadas estrechamente con la tasa de evapotranspiración de los cultivos y su producción de biomasa. A pesar de su importancia, usualmente no se miden de manera directa debido al tiempo invertido y costo; sin embargo, se pueden estimar a gran escala y en tiempo casi real mediante información espectral captada en imágenes de satélite, pero esto requiere de su validación a nivel de campo. Se desarrollaron y validaron modelos de regresión lineal simple utilizando 13 índices de vegetación (IV) relacionados con el IAF y la FCV en alfalfa (Medicago sativa). Se usaron tres fuentes de información espectral: (i) La reflectancia para derivar los IV; (ii) fotografías digitales procesadas con Canopeo para estimar la FCV; y (iii) mediciones del IAF utilizando un ceptómetro. Se realizaron seis muestreos de campo entre marzo y junio de 2020, en cuatro parcelas de alfalfa situadas en Palmar de Bravo, Puebla, México. Para evaluar cada IV, se utilizó el coeficiente de determinación (R2) y la raíz del cuadrado medio del error (RCME). Se encontró que el IV más apropiado para estimar la FCV fue el VIgreen (Green Vegetation Index, R2 = 0.987 y RCME = 0.093). En el caso del IAF, el IV que presentó el mejor desempeño fue el Normalized Difference Vegetation Index (NDVI), R2 = 0.935 y RCME = 0.746). Los resultados mostraron la aptitud y utilidad práctica de la información espectral para estimar las variables biofísicas en el cultivo de alfalfa y su monitoreo.

Summary: Carya illinoinensis (Wangenh.) K. Koch is a fruit tree with high economic value. However, this crop is very sensitive to zinc (Zn) deficiency in alkaline soils, where an alternative to minimize this problem is the edaphic supply of this micronutrient. Thus, the objective of this research is to evaluate the response of some physiological variables (trunk diameter, fruiting shoot length, terminal leaflet area and leaf Zn concentration), yield components (kg tree-1, nut weight, kernel percentage and alternation index) to the edaphic Zn chelate application in pecan nut “Western Schley” for three years in Chihuahua, Mexico. Five edaphic doses of Zn chelate (Carboxy Zn®, Innovak Global, México kg ha-1) T1 (8.5), T2 (17), T3 (34), T4 (51), T5 (68), where T0 corresponds to the control (no application) were evaluated in a split-plot experimental design with five replications. Statistical analyses showed statistical differences in physiological parameters such as trunk diameter and shoot length (19.93 and 19.27 cm, respectively), terminal leaflet area (34.08 cm2) and leaf Zn concentration (34.93 mg kg-1) with soil application of 8.1 (kg ha-1 of Carboxy Zn), as well as yield components (12.82 kg tree-1, 7.82 g nut weight and 59.15 kernel percentage) and minimize the bearing alternation index. The edaphic application of Carboxy Zn could be an alternative to Zn supply in the agronomic management of commercial pecan nut orchards in alkaline soils.

Resumen: Carya illinoinensis (Wangenh.) K. Koch., es un frutal con alto valor económico, sin embargo, es un cultivo muy sensible a la deficiencia de zinc (Zn) en suelos alcalinos, donde una alternativa para minizar este problema es el suministro edáfico de este micronutriente. El objetivo de esta investigación fue evaluar la respuesta de variables fisiológicas (diámetro de tronco, longitud de brote fructífero, área del foliolo terminal y concentración foliar de Zn) y componentes de rendimiento (kg árbol-1, peso de la nuez, porcentaje de la almendra e índice de alternancia), a la aplicación de quelato de Zn en nogal pecanero “Western Schley”. Durante tres años en Chihuahua, México, se evaluaron cinco dosis edáficas de quelato Zn (Carboxy Zn®, Innovak Global) en kg ha-1 de los siguientes tratamientos: T1 (8.5), T2 (17), T3 (34), T4 (51), T5 (68), donde T0 corresponde al testigo (sin aplicación) en un diseño experimental de parcelas dividas con 5 repeticiones. El análisis estadístico reflejó diferencias estadísticas con la aplicación edáfica de 8.1 (kg ha-1 de Carboxy Zn) en parámetros fisiológicos como diámetro de tronco y longitud de brote (19.93 y 19.27 cm respectivamente), área del folíolo terminal (34.08 cm2) y concentración foliar de Zn (34.93 mg kg-1). Así como los componentes de rendimiento (12.82 kilogramos fruto árbol-1, 7.82 g peso de la nuez y 59.15 porcentaje de la almendra) y minimizarón el índice de alternancia. La aplicación edáfica de Carboxy Zn, podría ser una alternativa al suministro de Zn en el manejo agronómico de huertos comerciales de nogal pecanero en suelos alcalinos.

Abstract Background: Lobelia villaregalis is an endemic and endangered species in Jalisco, Mexico. Knowing the structure and genetic diversity of populations of species at risk can contribute to improving strategies for their conservation. This information has not been generated for L. villaregalis. Questions: 1) Does L. villaregalis present low levels of genetic diversity?, 2) Are there genetic differences between its populations?. Studied species: Lobelia villaregalis T.J. Ayers (Campanulaceae: Lobelioideae), herbaceous perennial. Study site and dates: During 2018-2020, field work was carried out in El Bosque La Primavera Natural Protected Area, in Zapopan, Jalisco, in order to locate new populations of the species and collect leaf material. Methods: The diversity and genetic structure of 87 individuals in five populations were evaluated using ISSR molecular markers. Results: The average genetic diversity of L. villaregalis is low (He = 0.057, P = 48.17 %, I = 0.110) as well as the total diversity (HT = 0.069). Molecular analysis of variance showed that most of the genetic variation (92 %) occurred within populations. The Mantel test indicates that there is no correlation between the genetic distances and the geographical distances for the five populations of the species (R = 0.64, P = 0.18). With the genetic assignment analysis, 4 groups were identified, however there is no genetic structure (GST = 0.060). Conclusions: Lobelia villaregalis requires urgent actions of conservation to maintain the genetic diversity present in all its populations, giving the highest priority to three of them.

Resumen Antecedentes: Lobelia villaregalis es una especie endémica y en peligro de extinción en Jalisco, México. Conocer la estructura y diversidad genética de las poblaciones de especies en riesgo puede contribuir a mejorar las estrategias para su conservación. Esta información no se ha generado para L. villaregalis. Preguntas: 1) ¿Presenta L. villaregalis niveles bajos de diversidad genética?, 2) ¿Existen diferencias genéticas entre sus poblaciones? Especies de estudio: Lobelia villaregalis T.J. Ayers (Campanulaceae: Lobelioideae), herbácea perenne. Sitio y años de estudio: Durante 2018-2020 se realizó trabajo de campo en el Área Natural Protegida Bosque La Primavera, Zapopan, Jalisco, para localizar nuevas poblaciones de la especie y recolectar material foliar. Métodos: Se evaluó la diversidad y estructura genética de 87 individuos en cinco poblaciones utilizando marcadores moleculares ISSR. Resultados: La diversidad genética promedio de L. villaregalis es baja (He = 0.057, P = 48.17 %, I = 0.110) así como la diversidad total (HT = 0.069). El análisis de varianza molecular mostró que la mayor parte de la variación genética (92 %) ocurrió dentro de las poblaciones. La prueba de Mantel indica que no hay correlación entre las distancias genéticas y las distancias geográficas para las cinco poblaciones estudiadas (R = 0.64, P = 0.18). Con el análisis de asignación genética se identificaron 4 grupos, sin embargo, no existe estructura genética (GST = 0.060). Conclusiones: Lobelia villaregalis requiere acciones urgentes de conservación para mantener la diversidad genética de todas sus poblaciones, dando máxima prioridad a tres de ellas.

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 contamination with toxic metals brings along severe environmental issues. Among these metals, copper (Cu) is harmful to plant development when it reaches high contamination levels in the soil. Thus, identifying species capable of resisting this contamination type helps these sites’ revegetation and decontamination processes. Therefore, the present study aimed to investigate the tolerance of Cedrela fissilis plants to excess Cu through morphophysiological and biochemical variables. C. fissilis seedlings were subjected to five concentrations of Cu (0, 2, 4, 6, and 8 mg L-1). The experimental design was completely randomized, with five treatments and four repetitions. Morphophysiological (number of leaves, shoot height, root length, dry weight, morphological variables of the root system, and leaf area) and biochemical (antioxidant enzymes, lipid peroxidation, hydrogen peroxide concentration, and photosynthetic pigments) traits and Cu accumulated in roots and shoot were evaluated. High concentrations of Cu had a negative effect on the shoot and root dry weight, photosynthetic rate, stomatal conductance, and transpiration rate. Overall, Cu increased the activity of the antioxidant enzymes and lipid peroxidation. Therefore, Cu incidence in the nutrient solution has negatively influenced the biochemical and physiological traits of C. fissilis seedlings to the detriment of their growth. Thus, it was possible to identify sensitive behavior by the investigated species. Because of these features, C. fissilis seedlings can be used as markers for copper-contaminated areas. issues (Cu soil Thus sites processes Therefore C 0, 0 (0 2 4 6 L1. L1 L 1 . L-1) randomized repetitions number leaves height length weight system area peroxidation concentration pigments evaluated rate conductance Overall growth features coppercontaminated contaminated areas ( L-1 L-

RESUMO A contaminação do solo com metais tóxicos traz consigo graves problemas ambientais. Dentre esses metais, o cobre (Cu) é prejudicial ao desenvolvimento das plantas quando atinge elevados níveis de contaminação no solo. Assim, identificar espécies capazes de resistir a esse tipo de contaminação auxilia nos processos de revegetação e descontaminação desses locais. Portanto, o presente estudo teve como objetivo investigar a tolerância de plantas de Cedrela fissilis ao excesso de Cu através de variáveis morfofisiológicas e bioquímicas. Mudas de C. fissilis foram submetidas a cinco concentrações de Cu (0, 2, 4, 6 e 8 mg L-1). O delineamento experimental foi inteiramente casualizado, com cinco tratamentos e quatro repetições. Características morfofisiológicas (número de folhas, altura da parte aérea, comprimento da raiz, massa seca, variáveis morfológicas do sistema radicular e área foliar) e bioquímicas (enzimas antioxidantes, peroxidação lipídica, concentração de peróxido de hidrogênio e pigmentos fotossintéticos) e Cu acumulado nas raízes e folhas foram avaliados. Altas concentrações de Cu tiveram efeito negativo no peso seco da parte aérea e das raízes, na taxa fotossintética, na condutância estomática e na taxa transpiratória. No geral, o Cu aumentou a atividade das enzimas antioxidantes e a peroxidação lipídica. Portanto, a incidência de Cu na solução nutritiva influenciou negativamente as características bioquímicas e fisiológicas das mudas de C. fissilis em detrimento do seu crescimento. Assim, foi possível identificar o comportamento sensível da espécie investigada. Devido a essas características, mudas de C. fissilis podem ser utilizadas como bioindicadoras de áreas contaminadas por cobre. ambientais (Cu Assim locais Portanto C 0, 0 (0 2 4 L1. L1 L 1 . L-1) casualizado repetições número raiz seca foliar lipídica fotossintéticos avaliados fotossintética transpiratória geral crescimento investigada ( L-1 L-

ABSTRACT Alternative techniques for cultivation without soil are widespread; however, studies comparing hydroponic systems still need to be studied, mainly in semi-arid regions. The present study aimed to evaluate the effect of hydroponic systems on the yield and quality of lettuce cultivars subjected to different electrical conductivities of the nutrient solution. The research was conducted in a greenhouse, adopting a completely randomized design in a 2 × 2 × 3 factorial scheme, being two lettuce cultivars (Cinderela and Rubinela), two electrical conductivities (2.90 and 1.6 dS m-1), and three hydroponics systems (NFT, semi-hydroponic, and floating), with three replications. The number of leaves, leaf succulence, specific leaf area, leaf fresh mass, total dry mass, leaf area, titratable acidity, vitamin C, and soluble solids were evaluated. Cinderela cultivar showed the highest average leaf fresh mass, total dry mass, leaf area, and vitamin C values. The NFT and floating systems provided the highest leaf yield and quality, especially in the solution of 1.60 dS m-1. The semi-hydroponic system provided greater development of the plants with a more concentrated nutrient solution (2.90 dS m-1). widespread however studied semiarid semi arid regions greenhouse scheme Rubinela, Rubinela , Rubinela) 2.90 290 90 (2.9 16 1 6 1. m1, m1 m m-1) NFT, (NFT semihydroponic, semihydroponic hydroponic, floating, floating) replications leaves succulence area mass acidity evaluated values 160 60 m1. m-1 . 2.9 29 9 (2. m- 2. (2 (

RESUMO Técnicas alternativas de cultivo sem solo são difundidas; no entanto, estudos comparando os sistemas hidropônicos ainda precisam ser estudados, principalmente em regiões semiáridas. O presente estudo teve como objetivo avaliar a efeito de sistemas hidropônicos na produtividade e qualidade de cultivares de alface submetidas a diferentes condutividades elétricas da solução nutritiva. A pesquisa foi conduzida em casa de vegetação, adotando delineamento inteiramente casualizado. em esquema fatorial 2 × 2 × 3, sendo duas cultivares de alface (Cinderela e Rubinela), duas condutividades elétricas (2,90 e 1,6 dS m-1), e três sistemas hidropônicos (NFT, semi-hidropônico e floating), com três repetições. Foram avaliados número de folhas, suculência foliar, área foliar específica, massa fresca foliar, massa seca total, área foliar, acidez titulável, vitamina C e sólidos solúveis. A cultivar Cinderela apresentou maior massa fresca de folhas, massa seca total, área foliar, acidez titulável e vitamina C e sólidos solúveis. Os sistemas NFT e floating proporcionaram maior produtividade e qualidade foliar, especialmente na solução de 1,60 dS m-1. O sistema semi-hidropônico proporcionou maior desenvolvimento das plantas com solução nutritiva mais concentrada (2,90 dS m-1). difundidas entanto estudados semiáridas vegetação casualizado 3 Rubinela, Rubinela , Rubinela) 2,90 290 90 (2,9 16 1 6 1, m1, m1 m m-1) NFT, (NFT semihidropônico semi hidropônico floating, floating) repetições folhas específica total solúveis 160 60 m1. 1. m-1 . 2,9 29 9 (2, m- 2, (2 (

ABSTRACT While zinc (Zn) is an essential element for plant metabolism, anthropic activities and poor agricultural practices as well as frequent use of pesticides and fertilizers rich in this element can cause toxic levels of Zn to plants. A study was done under greenhouse conditions in Tunja, Colombia in which bulb onion seedlings (Allium cepa L.) were exposed to 0 (control), 20, 40, and 80 mg L-1 of Zn in mixture with a nutrient solution containing macro and micronutrients. The excess Zn in the solution had a rather drastic effect on the accumulation of dry weight and reduced the absolute growth rate, the specific leaf area, the water uptake, the water use efficiency, the leaf area, the length of all roots per plant, and on the contrary, increased the content of total soluble solids in the juice of the bulb. Thus, most growth-related variables were negatively affected from 20 mg L-1 and up of Zn in solution. In addition, the toxic effect of Zn is more drastic on plants growing in nutrient solution compared to those growing in soil. The experiment lasted until 54 days after transplanting, which was the limit for plant survival, especially at higher concentrations of Zn, so it can be inferred that these plants have low tolerance to high Zn contents in the substrate.

RESUMEN A pesar de que el zinc (Zn) es un elemento esencial para el metabolismo de las plantas, las actividades antrópicas y las malas prácticas agrícolas, así como también, el uso frecuente de plaguicidas y fertilizantes ricos en este elemento pueden causar que niveles tóxicos de Zn estén disponibles para las plantas. Se realizó en Tunja, Colombia, un trabajo en invernadero en el que plántulas de cebolla de bulbo (Allium cepa L.) se expusieron a 0 (control), 20, 40, y 80 mg L-1 de Zn en solución nutritiva. El exceso de Zn en la solución tuvo un efecto bastante drástico sobre la acumulación de peso seco, también redujo los valores de la tasa absoluta de crecimiento, del área foliar especifica, del consumo de agua, de la eficiencia en el uso del agua, del área foliar, de la longitud de raíces y, por el contrario, incrementó el contenido de solidos solubles totales en el zumo del bulbo. De este modo, la mayoría de las variables relacionadas con el crecimiento fueron afectadas negativamente a partir de 20 mg L-1 de Zn en la solución. Además, el efecto tóxico del Zn es más drástico cuando las plantas crecen en solución nutritiva en comparación a cuando crecen en suelo. Por otro lado, el experimento duró solo hasta 54 días después del trasplante, dado que fue el momento máximo que pudieron soportar las plantas, especialmente aquellas que se expusieron a contenidos de Zn más elevados, con lo que se puede inferir que estas plantas tienen baja tolerancia a contenidos elevados de Zn en el sustrato.

Abstract Distichlis spicata is a gramineous halophyte species that grow around the coastal areas. The objective of the study was to identify the modifications in the anatomical structure of stomates of the D. spicata leaf epidermis, cultivated with irrigation and without irrigation conditions. Two populations were selected, 1) plants of D. spicata with irrigation and 2) plants of D. spicata without irrigation. Ten plants per replication were selected from each population, and from each selected plant, the fourth leaf was taken. Each leaf was cut longitudinally into four segments which were dried and analyzed using an Electronic Scanning Microscope. The variables measured were the stomatal density, length, and width of stomates and pores, the stomatal area, the proportion of the pore area concerning the size of the stomata, and the stomata proportion per surface. The results showed that D. spicata populations with irrigation and without irrigation showed anatomical modifications in the structure of stomates in the adaxial epidermis but not in the abaxial epidermis. In the adaxial epidermis, the plants with irrigation showed higher values of stoma length, stoma width, stoma area and pore length, while plants without irrigation showed higher values of proportion pore/stoma and stomatal density. The D. spicata plants without irrigation showed small stomates than plants with irrigation, also, the plants without irrigation, increased the accumulation of salt crystals in the abaxial epidermis.

Resumen Distichlis spicata es una especie de gramínea halófita que crece en las zonas costeras. El objetivo del estudio fue identificar las modificaciones en la estructura anatómica de estomas de la epidermis foliar de D. spicata, cultivadas con riego y sin riego. Se seleccionaron dos poblaciones, 1) plantas de D. spicata con riego y 2) plantas de D. spicata sin riego. De cada población se seleccionaron 10 plantas por repetición y de cada planta seleccionada se tomó la cuarta hoja. Cada hoja se cortó longitudinalmente en cuatro segmentos que se secaron y analizaron utilizando un microscopio electrónico de barrido. Las variables medidas fueron la densidad estomática, largo y ancho de estomas y poros, el área estomática, la proporción del área de poros con respecto al tamaño de los estomas y la proporción de estomas por superficie. Los resultados mostraron que la población de D. spicata con riego y sin riego mostraron modificaciones anatómicas en la estructura de los estomas en la epidermis adaxial pero no en la epidermis abaxial. En la epidermis adaxial, las plantas con riego presentaron valores más altos de longitud de estoma, ancho de estoma, área de estoma y longitud de poro, mientras que las plantas sin riego mostraron valores más altos de proporción poro/estoma y densidad estomática. Las plantas de D. spicata sin riego presentaron estomas más pequeños respecto a las plantas con riego; además, las plantas sin riego incrementaron la acumulación de cristales de sal en la epidermis abaxial.