Heterogeneous salinity in the root system of bell pepper in greenhouse

Abstract

A B S T R A C TThe split-root technique was used as a strategy to reduce saline stress on pepper. A completely randomized design with six treatments and four replicates was used. The treatments consisted of six saline water application strategies (T1 -salinized nutrient solution (S1 = 1.4 dS m ) throughout the cycle, T3 -S1 and S2 throughout the cycle, using two emitters and without splitting the root system, T4 -S1 and S2, using two emitters and splitting the root system by a plastic film, T5 -S1 and S2, using two emitters and splitting the root system, alternating the solutions every 15 days, T6 -S1 and S2, using two emitters and without splitting the root system, alternating the solutions every 15 days). Five fruit harvests were performed, and the plants were harvested at 85 days after initiation of treatments and evaluated for the following variables: leaf number, leaf area, plant height, stem diameter, shoot dry matter (stem + leaves + fruits), root dry matter, number of fruits, fresh fruit weight and fruit production per plant. Most of the variables were reduced by the salinity of irrigation water. The highest fruit yields were obtained using low-salinity water, with the mixture of non-saline and saline waters, and alternating biweekly when the root system was split, demonstrating the viability of these three techniques.Salinidade heterogênea no sistema radicular de pimentão em ambiente protegido R E S U M O A técnica de divisão do sistema radicular foi utilizada como estratégia para reduzir o estresse salino em pimentão. Utilizou-se o delineamento inteiramente casualizado com seis tratamentos e quatro repetições. Os tratamentos foram constituídos por seis estratégias de aplicação de água salina (T1 -solução nutritiva não salinizada (S1 = 1,4 dS m ) durante todo o ciclo; T3 -S1 e S2 durante todo o ciclo, utilizando dois emissores e sem divisão do sistema radicular; T4 -S1 e S2, utilizando dois emissores e divisão do sistema radicular por um filme plástico; T5 -S1 e S2, utilizando dois emissores com divisão do sistema radicular, alternando-se as águas a cada 15 dias; T6 -S1 e S2, utilizando dois emissores sem divisão do sistema radicular, alternando-se as águas a cada 15 dias). Foram realizadas cinco colheitas de frutos e as plantas foram coletadas aos 85 dias após início dos tratamentos, e avaliadas quanto às seguintes variáveis: número de folhas, área foliar, altura da planta, diâmetro do caule, massa seca parte aérea (caule + folhas + frutos) e de raiz, número de frutos, massa fresca de frutos e produção de frutos por planta. A maioria das variáveis foi reduzida pela salinidade da água de irrigação. Os maiores rendimentos de frutos foram obtidos com uso de água de baixa salinidade, com a mistura de águas não salinas e salinas, e com alternação quinzenal quando utilizando a divisão do sistema radicular, demonstrando a viabilidade destas três técnicas.

Attenuation of salt stress on the physiology and production of bell peppers by treatment with salicylic acid

“…Nevertheless, these adaptive strategies are inefficient to cope with the osmotic and ionic effects, which induce a reduction in chloroplast pigments and in the photosynthesis, growth and production of crops (Yang et al, 2020). Oliveira et al (2018) found that irrigation with 4.5 dS m-1 saline water reduces growth and production in bell pepper. The authors stated that the highest fruit yields were achieved with the use of low-salinity water, a mixture of non-saline and saline waters and fortnightly alternation of high-salinity water.…”

Shading Levels and Substrates Affect Morphophysiological Responses and Quality of Anadenanthera peregrina (L.) Speg Seedlings

“…Low water loss in seedlings under 50% and 70% of shading favored the elongation of the root system and its exploitation in the soil (Oliveira et al, 2018), the moisture was longer kept, due to lower evaporation substrate, which favored its development, in the seedlings with smaller XL. However, it should be noted that even with smaller roots under 0% and 30% of shading levels, there was an increase in the morphometric aspects of reserve structures, which contributes to their ecological tolerance to environmental conditions.…”

Bell pepper germination and seedling’s parameters under different osmotic potentials

“…This condition is worse in regions with low precipitation, irrigation with low-quality water, successive application of fertilizers and amendments with high salt content (Silva et al, 2020). The soil salinity effects on plants are usually related to the dynamics of water and nutrient absorption by roots and the toxic levels of some elements (Maciel et al, 2012;Oliveira et al, 2018;Sá et al, 2019). Beloti et al (2022) Bell pepper germination and seedling's...…”