Abstract The use of mulch in soil to produce vegetables increases the yield and quality of harvested products; however, these increases are conditioned by the type of mulch, whether plastic or organic. An experiment was performed in cabbage (Brassica oleracea L. var Capitata) culture during the 2021-2022 season, with the aim of evaluating its response on water use efficiency, mineral nutrition and yield to four types of mulches in the soil. Four treatments were evaluated (soil with black plastic mulch, white plastic mulch, mulch with wheat straw and a control without mulching), distributed under a randomized block design with four repetitions. The results showed that white plastic mulch increased the total biomass, cabbage weight and leaf weight, compared to the rest of the treatments. The use of both plastic mulches (black and white) increased the concentration of nitrates in the cell extract of the midrib. The leaf temperature increased only due to the use of black plastic mulch. Finally, the efficiency in the use of water was higher in the treatments with plastic mulch and lower in the soil without mulching. Considering the greater efficiency in the use of water, yield and mineral nutrition, it was concluded that the soil with plastic mulch is the most recommended to produce cabbage in the Mexicali Valley, Mexico.

Resumen El uso del acolchado en suelo para producir hortalizas incrementa el rendimiento y la calidad de los productos cosechados; sin embargo, estos incrementos se encuentran condicionados al tipo de acolchado, ya sea plástico u orgánico. Se realizó un experimento en el cultivo de repollo (Brassica oleracea L. var Capitata) durante la temporada de 2021-2022, con el objetivo de evaluar su respuesta sobre la eficiencia en el uso del agua, nutrición mineral y rendimiento a cuatro tipos de acolchados en suelo. Se evaluaron cuatro tratamientos (suelo con acolchado plástico color negro, color blanco, acolchado con paja de trigo y un control sin acolchar) distribuidos bajo un diseño de bloques al azar con cuatro repeticiones. Los resultados mostraron que el acolchado plástico blanco incrementó la biomasa total, el peso del repollo y peso de las hojas, en comparación al resto de los tratamientos. El uso de ambos acolchados plásticos (blanco y negro) incrementó la concentración de nitratos en el extracto celular de la nervadura central. La temperatura foliar incrementó solo por el uso del acolchado plástico negro. Finalmente, la eficiencia en el uso del agua resultó mayor en los tratamientos con acolchado plástico y menor en el suelo sin acolchar. Considerando la mayor eficiencia en el uso del agua, rendimiento y nutrición mineral se concluyó que el suelo con acolchado plástico es el más recomendable para producir repollo en el valle de Mexicali, México.

RESUMO A salinidade do solo em regiões áridas e semi-áridas afeta a produção e qualidade de frutos da melancieira. Objetivou-se com esse trabalho avaliar a condição enxertada da planta como alternativa para reduzir os efeitos da salinidade. Foi utilizado o delineamento em blocos casualizados com três repetições. As cultivares Sangria, Summer Flavor 800 e Summer Flavor 840 constituiram os tratamentos, como planta com e sem enxertia. O enxerto foi realizado sobre o híbrido interespecífico Strong Tosa (C. maxima x C. moschata). O enxerto favoreceu a produção comercial, peso, comprimento e diâmetro do fruto em 160,5%, 36,5%, 12,0% e 7,5%, respectivamente, em termos médios das três cultivares. ‘Sangria’ apresentou a melhor resposta em produtividade com 57,1 t ha-1, peso 5,8 kg, comprimento 35,0 cm e diâmetro 17,8 cm de fruto. O enxerto favoreceu em 6,3% o valor de luminosidade e redução de 6,4% no ângulo hue. ‘Summer Flavor 840’ apresentou a melhor resposta em luminosidade com valor de 48,3 e ângulo hue de 26,4°. Firmeza, °Brix e teor de licopeno não foram afetados pela enxertia. O enxerto das plantas constitui alternativa em solos salinos para melhorar a produção e qualidade dos frutos.

ABSTRACT Salinity of soil in arid and semiarid regions is a problem that affects the production and quality of fruit. That’s while we evaluated grafting on watermelon plants as an alternative to reduce the salinity effects. The experimental design was of randomized blocks, three treatments (cultivars Sangria, Summer Flavor 800 and Summer Flavor 840) with three repetitions. The cultivars were evaluated in grafted and ungrafted condition. The rootstock used for grafting was the interspecific hybrid Strong Tosa (C. maxima x C. moschata). In average terms for the three cultivars, grafting increased commercial production, weight, length and diameter of fruits in 160.5%, 36.5%, 12.0% and 7.5%, respectively. Sangria presented the best answer in production with 57.1 t ha-1, weight 5.8 kg, length 35.0 cm and diameter 17.8 cm of fruits. Also, grafting favored in 6.3% the luminosity and reduced 6.4% Hue angle. Summer Flavor 840 showed the best result in luminosity with 48.3 and hue angle 26.4°. Firmness, °Brix and lycopene content were not modified by grafting. Grafting represents an alternative for watermelon production in saline soils, improving yield and quality of the fruits.

Cucumber production has increased in Baja California, but its production in the Mexicali Valley is limited due to the semi-arid climate typical of the region. One option for the production of this crop can be greenhouse systems and house-shadow. In this sense, the objective of this study was evaluated the influence of the use of greenhouse and house-shadow in the production of Cucumis sativus in Mexicali Valley. The results showed that the micro-environments generated in both systems had similar temperatures (40 and 39 ° C) during the experiment. However, the relative humidity present in the greenhouse showed more lower values (21%, P < 0.00013) than present in house-shadow (37%). On the other hand the effect of micro-climate in the production of fruit was slightly superior greenhouse (19 kg/m²) than house-shadow (17 kg/m²). Finally, future studies are recommended to know in detail the biochemical and physiological responses of cucumber in the semi-arid agroecosystem in the Mexicali Valley.

La producción de pepino se ha incrementado en Baja California; no obstante, su producción en el valle de Mexicali es limitada debido al clima semiárido característico de la región. Una opción para la producción de este cultivo pueden ser los sistemas de invernadero y malla-sombra. En este sentido, el presente estudio tuvo como objetivo evaluar la influencia del uso de invernadero y casa-sombra en la producción de Cucumissativusen el valle de Mexicali. Los resultados obtenidos mostraron que los micro-ambientes generados en ambos sistemas presentaron temperaturas similares (40 y 39 °C) durante el experimento. No obstante, en el caso de la humedad relativa fue el sistema de invernadero el que mostró valores menores (21%, P< 0,00013) a los registrados en el sistema de malla-sombra (37%). Por otra parte, al evaluar el efecto del microclima de ambos sistemas en el rendimiento se observó que el sistema de invernadero presentó una producción de 19 kg/m², la cual fue ligeramente superior al sistema de malla-sombra 17 kg/m². Finalmente, futuros estudios son recomendados para poder conocer en detalle la respuesta fisiológica y bioquímica del pepino en las condiciones semiáridas del agroecosistema del valle de Mexicali.