Effect of silicon and humic substances on the productivity and absorption of minerals in cucumber

Objective: This work is to evaluate the effect of potassium silicate and humic substances to mitigate salt stress in cucumber grown in greenhouse. Design/methodology/approach: The design that was used was a completely randomized with factorial arrangement. The first factor is the varieties of cucumber (Var); Induran (I) and SV2516 (SV), the second factor is potassium silicate (Si) with doses 0, 10, 20 mL·L-1 and the third factor is humic substances (SH) with doses 0, 10, 20 kg / ha. Results: The results showed that the best interaction was SV * SH20 for the NFP and Rend variables. In the fruit content of N and Ca it was I * SH10 and in K and P it was SV * Si20, for the rest of the minerals such as Mg, Fe and Cu the interactions that stood out were SV * Si10, SV * Si20 and I * Si10 respectively. The best interaction in sheet mineral content was I * SH20 in N, SV * SH10 for P and K, and SV * Si20 for Cu. Study limitations/implications: There was no significant difference in Ca, Mg and Fe minerals in leaf. Findings/conclusions: At least one of the interactions of cultivars and doses of biostimulants favored agronomic variables, quality and mineral absorption in fruit. Key words:  Salt stress, humic substances, potassium silicate.O Objective: To evaluate the effect of potassium silicate and humic substances in the mitigation of salt stress in cucumber grown in a greenhouse. Design/Methodology/Approach: A completely randomized design with factorial arrangement was used. The first factor was the cucumber varieties (Var): Induran (I) and SV2516 (SV). The second factor was potassium silicate (Si), with doses of 0, 10, and 20 mL·L-1. The third factor was humic substances (SH), with doses of 0, 10, and 20 kg/ha. Results: The best interaction for the NFP and Y variables was SV*SH20. The N and Ca content in the fruit was I*SH10, while the K and P content was SV*Si20. Meanwhile, Mg, Fe, and Cu interactions stood out with SV*Si10, SV*Si20, and I*Si10, respectively. The best interaction in leaf mineral content was I*SH20 (N), SV*SH10 (P and K), and SV*Si20 (Cu). Study Limitations/Implications: There was no significant difference in Ca, Mg, and Fe in leaf. Findings/Conclusions: At least one of the interactions between cultivars and bio stimulant doses favored agronomic traits, quality, and mineral absorption in fruit

PRODUCCIÓN DE TOMATE EN INVERNADERO CON COMPOSTA Y VERMICOMPOSTA COMO SUSTRATO

The organic production of food is an alternative for consumers that prefer food free of pesticides, synthetic fertilisers, and with a high nutritional value. The purpose of this study was to evaluate substrates prepared with mixtures of compost and vermicompost with sand, at various levels, under greenhouse conditions. The tomato hybrid SUN-7705 (Lycopersicon esculentum Mill) was analized in four substrates that included compost and vermicompost mixed at three different proportions (100, 75 y 50 %). The treatments were distributed in a completely randomised design with a factorial arrangement of 4x3 and five replicates. The greatest average yield (39.811 t ha) was obtained with the compost generated by decomposing bovine manure, corn stover (Zea mays L.), elephant grass (Pennisetum purpureum Schumacher) and black earth (CEMZT) at 75% + sand, and with the vermicompost generated by manure, bahiagrass (Paspalum notatum Flügge) and black earth (VEPT) at 100 and 50% + sand. This yield was greater than that recorded for organic tomato production in the field, without affecting the quality of the fruit

The Use of Iodine, Selenium, and Silicon in Plant Nutrition for the Increase of Antioxidants in Fruits and Vegetables

Iodine, silicon, and selenium are considered elements not essential for the metabolism of plants. However, these elements are vital for humans, and their presence as traces in food is beneficial. The use of I, Si, and Se in the fertilization programs of the plants allows, on the one hand, the mineral biofortification of the crops and, on the other hand, through mechanisms not yet fully understood, the production and accumulation of more antioxidants in the edible organs. This chapter provides an overview about the use of I, Si, and Se both for mineral biofortification and for the increase in the concentration of antioxidants in plants, with an emphasis on redox metabolism adjustments and antioxidant chemical species studied. The scope of the chapter is on horticultural species in the open field and under greenhouse or tunnels

Multiplication of native endomycorrhizae isolated from arid soils on organic substrates in wheat plants ( Triticum aestivum)

Purpose Organic residues of coffee pulp, sugarcane bagasse and mature bovine manure are a source of organic matter and nutrients for the multiplication of endomycorrhizae consortia. Therefore, the purpose of this research is to multiply the AMFs in such substrates to decrease soil and water pollution.Method A pot experiment under greenhouse conditions was conducted in order to evaluate the influence of agricultural residues (C2-GEC, C3-PAR, C12-PRO, C14-ZAR) with different genera of endomycorrhizae isolated from semi-arid soils, 75 days after the crop was established. Agronomic characteristics and mineral content of N, K, Ca, Mg, and Fe in root and shoot were evaluated in wheat (Triticum aestivum).Results Multiplication of endomycorrhizae was influenced by the residue type. Greater production of spores was observed in the coffee pulp, followed by the sugarcane bagasse, where a higher colonization was obtained in combination of C2-GEC and C3-PAR consortia. This consortia combination also was one of those that have increased the content of N, K, Ca, Mg, and Fe in roots and shoots of wheat.Conclusion Combination of native endomycorrhiza substrates and consortia provides an alternative tool that benefits the physiology and nutrition of the plant to be used in sustainable agricultural production systems

Yield and quality of hybrid tomato grafted and cultivated under shade mesh and greenhouse

The objective was to determine the yield, fruit quality and root development of four grafted tomato hybrids grown under anti-aphid mesh cover and greenhouse. The grafted hybrids were grown under shade mesh and greenhouse from april to november 2014. Variables evaluated were: fruit weight per plant, number of clusters per plant, number of fruits per plant, polar and equatorial fruit diameter, vitamin C and lycopene contents, and root fresh and dry weight. Hybrids grafted and cultivated under anti-aphid mesh had higher quality than the production obtained under greenhouse. However, lycopene and vitamin C contents and accumulated root system dry matter are greater under greenhous

Influencia de cuatro concentraciones de solución Steiner sobre los nutrientes en la solución del suelo y productividad en tomate (Solanum lycopersicum L.)

El desarrollo y productividad de los cultivos agrícolas está directamente relacionado con el suministro nutricional que estos reciben. La hipótesis de esta investigación es que la concentración de iones medidos en la solución del suelo, permite evaluar la eficiencia del manejo nutricional y su efecto sobre el cultivo, así, la concentración de iones está condicionada por el aporte mineral y los procesos de intercambio iónico del suelo. El objetivo de ésta investigación, fue medir el efecto de la aplicación continua de cuatro concentraciones de solución nutritiva sobre la concentración de iones en la solución del suelo y la respuesta en el cultivo de tomate bajo invernadero. El ensayo se estableció en suelo calcáreo bajo un diseño de bloques completos al azar con tres repeticiones, con plantas de tomate indeterminado. Los tratamientos fueron cuatro concentraciones con diferente proporción de la solución Steiner modificada para el cultivo de tomate: 1) 50, 2) 75, 3) 100 y 4) 125%, que fueron aplicadas de forma continua por fertirriego. En cada tratamiento se extrajo la solución del suelo y se midió la concentración de los iones NO3-, K+ y Ca+2, el pH y la conductividad eléctrica durante 18 semanas. Al mismo tiempo, se midió la respuesta en el cultivo. La concentración de la solución nutritiva, aplicada de forma constante al cultivo de tomate, presenta una relación directa con la disponibilidad de nutrientes. La solución nutritiva al 125% generó mejor crecimiento, fisiología, calidad comercial y rendimiento agronómico. El calcio fue el único elemento que se detectó en niveles suficientes en la solución del suelo a partir de una concentración de 50% en la solución nutritiva, debido a su alta disponibilidad original del suelo

Estimación de Heterosis y Heterobeltiosis en Híbridos Interpoblacionales de Tomate de Cáscara (Physalis Ixocarpa Brot.)

The objective of the investigation was to evaluate progenitors and their crosses, and to estimate heterosis and heterobeltiosis in hybrid of husk tomato (Physalis ixocarpa Brot). The progenitors were UAN CC-S2 (1), a genotype of Physalis angulata (2), UAN CP-S2 (3), Gran Esmeralda (4), UAN CJ-S2 (5), Rendidora (6), and UAN 133- 05 (7). The crosses, plant to plant, were done under greenhouse conditions in autumn-winter of 2012; the evaluation of the crosses and the parents were done in the municipality of General Cepeda, Coahuila, Mexico, in the spring-summer of 2013, under a randomized block design with three repetitions. In yield, the best cross was 3*4, with yields of 47.19 t.ha-1, heterosis of 35.93%, and heterobeltiosis of 20.85%; however the 1*6 cross presented the highest values of heterosis and heterobeltiosis, 117.91 and 117.62% respectively; in number of fruits per plant, crosses 7*3 showed the highest values of heterosis and heterobeltiosis, 109.19 and 89.96% respectively; in terms of average fruit weight, equatorial diameter of fruit, and polar diameter of fruit, the best cross was the 3*4, that presented heterosis of 41.17, 11.40, and 12.56%, and heterobeltiosis of 37.99, 9.26, and 12.03%, respectively, although cross 1*5 values of heterosis and heterobeltiosis in average weight were 115.91 and 107.83% respectively. Among the populations studied there is genetic divergence, since they presented high values of heterosis; in addition, the maternal effects significantly influenced the variables under study, indicating the best direction of the cross.El objetivo de la investigación fue evaluar los progenitores y sus cruzas, y estimar la heterosis y la heterobeltiosis en híbridos de tomate de cáscara (Physalis ixocarpa Brot). Los progenitores fueron UAN CC-S2 (1), un genotipo de Physalis angulata (2), UAN CP-S2 (3), Gran Esmeralda (4), UAN CJ-S2 (5), Rendidora (6) y UAN 133-05 (7). Los cruzamientos planta a planta fueron en invernadero, en otoño-invierno de 2012; la evaluación de cruzas y progenitores se realizó en el municipio de General Cepeda, Coahuila, México, en primavera-verano de 2013, bajo un diseño de bloques al azar con tres repeticiones. En cuanto a rendimiento, la cruza más rendidora fue 3*4, con rendimientos de 47.19 t.ha-1, heterosis de 35.93% y heterobeltiosis de 20.85%; sin embargo, la cruza 1*6 presentó valores mayores de heterosis y heterobeltiosis, 117.91 y 117.62% respectivamente. Para número de frutos por planta, la cruza 7*3 mostró los valores de heterosis y heterobeltiosis mayores, 109.19 y 89.96% respectivamente. En cuanto a peso promedio del fruto, diámetro ecuatorial del fruto y diámetro polar del fruto, la mejor cruza fue la 3*4, que presentó heterosis de 41.17, 11.40 y 12.56% y heterobeltiosis de 37.99, 9.26 y 12.03% respectivamente, si bien la cruza 1*5 mostró valores de 115.91% de heterosis y 107.83% de heterobeltiosis en peso promedio del fruto. Entre las poblaciones estudiadas existe divergencia genética, puesto que presentaron altos valores de heterosis; además, los efectos maternos influyeron de forma significativa en las variables en estudio, indicando la mejor dirección de la cruza

Estimación de Heterosis y Heterobeltiosis en híbridos interpoblacionales de tomate de cáscara (Physalis Ixocarpa Brot.)

The objective of the investigation was to evaluate progenitors and their crosses, and to estimate heterosis and heterobeltiosis in hybrid of husk tomato (Physalis ixocarpa Brot). The progenitors were UAN CC-S2 (1), a genotype of Physalis angulata (2), UAN CP-S2 (3), Gran Esmeralda (4), UAN CJ-S2 (5), Rendidora (6), and UAN 133- 05 (7). The crosses, plant to plant, were done under greenhouse conditions in autumn-winter of 2012; the evaluation of the crosses and the parents were done in the municipality of General Cepeda, Coahuila, Mexico, in the spring-summer of 2013, under a randomized block design with three repetitions. In yield, the best cross was 3*4, with yields of 47.19 t.ha-1, heterosis of 35.93%, and heterobeltiosis of 20.85%; however the 1*6 cross presented the highest values of heterosis and heterobeltiosis, 117.91 and 117.62% respectively; in number of fruits per plant, crosses 7*3 showed the highest values of heterosis and heterobeltiosis, 109.19 and 89.96% respectively; in terms of average fruit weight, equatorial diameter of fruit, and polar diameter of fruit, the best cross was the 3*4, that presented heterosis of 41.17, 11.40, and 12.56%, and heterobeltiosis of 37.99, 9.26, and 12.03%, respectively, although cross 1*5 values of heterosis and heterobeltiosis in average weight were 115.91 and 107.83% respectively. Among the populations studied there is genetic divergence, since they presented high values of heterosis; in addition, the maternal effects significantly influenced the variables under study, indicating the best direction of the cross.El objetivo de la investigación fue evaluar los progenitores y sus cruzas, y estimar la heterosis y la heterobeltiosis en híbridos de tomate de cáscara (Physalis ixocarpa Brot). Los progenitores fueron UAN CC-S2 (1), un genotipo de Physalis angulata(2), UAN CP-S2 (3), Gran Esmeralda (4), UAN CJ-S2 (5), Rendidora (6) y UAN 133-05 (7). Los cruzamientos planta a planta fueron en invernadero, en otoño-invierno de 2012; la evaluación de cruzas y progenitores se realizó en el municipio de General Cepeda, Coahuila, México, en primavera-verano de 2013, bajo un diseño de bloques al azar con tres repeticiones. En cuanto a rendimiento, la cruza más rendidora fue 3*4, con rendimientos de 47.19 t.ha-1, heterosis de 35.93% y heterobeltiosis de 20.85%; sin embargo, la cruza 1*6 presentó valores mayores de heterosis y heterobeltiosis, 117.91 y 117.62% respectivamente. Para número de frutos por planta, la cruza 7*3 mostró los valores de heterosis y heterobeltiosis mayores, 109.19 y 89.96% respectivamente. En cuanto a peso promedio del fruto, diámetro ecuatorial del fruto y diámetro polar del fruto, la mejor cruza fue la 3*4, que presentó heterosis de 41.17, 11.40 y 12.56% y heterobeltiosis de 37.99, 9.26 y 12.03% respectivamente, si bien la cruza 1*5 mostró valores de 115.91% de heterosis y 107.83% de heterobeltiosis en peso promedio del fruto. Entre las poblaciones estudiadas existe divergencia genética, puesto que presentaron altos valores de heterosis; además, los efectos maternos influyeron de forma significativa en las variables en estudio, indicando la mejor dirección de la cruza

Cinética de crecimiento in vitro de Brevibacillus brevis en diferentes medios de cultivo

Abstract The development of techniques for the reproduction of soil beneficial rhizobacteria opens up a range of alternatives for your research. The ignorance of chemical and physical conditions of an optimal means for development Brevibacillus brevis generates this research by evaluating five liquid culture media (SM 1%, SM 0.5%, SM 0.1%, LB and NFb), three pHs (6, 7 and 8) and two incubation times (48 and 96 h). The objective of this work was to evaluate an optimal medium for the reproduction of the bacteria at the laboratory level. The methodology included processing, standardizing of culture media, reactivation of the strain, Gram staining, inoculation, incubation for reproduction and bacterial count. The triple interaction showed that the medium SM 1% (Sábila and Melaza), with pH 7 and 48 h had the best results, compared to the other media and conditions with 15.38 x 1011 CFU mL-1.Resumen El desarrollo de técnicas para la reproducción de rizobacterias benéficas del suelo abre una gama de alternativas para su investigación. El desconocimiento de condiciones químicas y físicas de un medio óptimo para el desarrollo Brevibacillus brevis generó la presente investigación al evaluar cinco medios de cultivo líquidos (SM 1%, SM 0.5%, SM 0.1%, LB y NFb), tres pHs (6, 7 y 8) y dos tiempos de incubación (48 y 96 h). El objetivo fue determinar un medio óptimo para la reproducción de la bacteria en laboratorio. Se estandarizaron los medios de cultivo, reactivo la cepa, tinción de Gram, inoculación, incubación para reproducción y recuento de bacterias. La interacción demostró que el medio SM 1% (Sábila y Melaza), con pH 7 y 48 h tuvo los mejores resultados, comparado con los otros medios y condiciones con 15.38 x 1011 UFC mL-1

Respuestas de lechuga a la conductividad eléctrica con riego superficial y subirrigación

Salinity suppresses plant growth and reduce agricultural productivity due to a water deficit, ion toxicity, causing nutrient skewness. A sub-irrigation system on principle, is based on capillary rise of water, up to the root zone, decreasing nutrient leaching compared with traditional watering systems. In void areas of northern Mexico, there are often high levels of calcium (Ca), magnesium and sulphate in irrigation water, directly affecting the electrical conductivity (EC). This paper proposed to evaluate the effect of EC on the growth of lettuce plants using two types of irrigation systems: surface and sub-irrigation. The diameter of the plants was bigger in plants with surface irrigation system compared to those with sub-irrigation; however, plants sub-irrigated with solution 3.3 dS m-1 showed a higher fresh weight than those with surface irrigation, so this system is a good option to meliorate the effect of salinity. The rate of photosynthesis, transpiration and leaf conductance were not altered by the irrigation system at all, but transpiration and conductance were higher in sub-irrigated plants. A higher EC of the nutrient solution increased the bottom EC of the substrate, and the middle and top layer, and the surface irrigation system was higher compared to that presented by sub-irrigation. High EC of the nutrient solution did not attain the concentration of nitrogen or phosphorus whatsoever, but at elevated EC of the substance, the foliar potassium concentration did increased.La salinidad inhibe el crecimiento de las plantas y reduce la productividad agrícola a causa de un déficit hídrico, toxicidad por los iones que la inducen y al desbalance nutrimental que ocasiona. Un sistema de subirrigación parte del principio del ascenso capilar del agua hasta la zona radical, reduciendo la lixiviación de nutrimentos en comparación con los sistemas tradicionales de riego. En las zonas áridas del norte de México se presentan con frecuencia altos niveles de calcio (Ca), magnesio y sulfato en el agua de riego, lo que impacta directamente en la conductividad eléctrica (CE). El presente estudio se planteó con el objetivo de evaluar el efecto de la CE sobre el crecimiento de plantas de lechuga empleando dos tipos de sistemas de riego: superficial y subirrigación. El diámetro de las plantas fue mayor en plantas con riego superficial en comparación con aquellas con subirrigación; sin embargo, las plantas subirrigadas con solución de 3.3 dS m-1 mostraron un mayor peso fresco que aquellas con riego superficial, por lo que este sistema es una buena opción para mitigar el efecto por salinidad en lechuga. La tasa de fotosíntesis neta, transpiración y conductancia de la hojas no fueron afectadas por el sistema de riego empleado, pero la transpiración y conductancia fueron mayores en plantas subirrigadas. A mayor CE de la solución nutritiva se presentó un aumento en la CE de la parte inferior del sustrato, así como del estrato medio y superior, y con riego superficial esta fue mayor en comparación con subirrigación. La alta CE de la solución nutritiva no afectó la concentración de nitrógeno ni de fosforo, pero al elevarse la CE de la solución se incrementó la concentración foliar de potasio