Is Salt Stress Killing Your Bell Peppers? A Guide to Building Resilient Crops

Kai Mendoza in Climate & Environment June 2025 • 5 min read.

"Discover how to identify and mitigate the impact of salinity on bell pepper growth for healthier, more productive harvests."

Bell peppers (Capsicum annuum L.) are economically significant, with substantial cultivation in Brazil and globally. In Brazil, about 13,000 hectares are dedicated to bell pepper production, yielding close to 290,000 tons of fruit annually. The Northeast region of Brazil accounts for 31% of the country's bell pepper production, particularly in Bahia, Ceará, and Pernambuco. However, bell pepper cultivation in this region faces challenges, especially from water scarcity and salinity issues.

Bell peppers, like many vegetables, are highly susceptible to water deficits, especially during flowering and fruit development. This vulnerability necessitates irrigation, yet the semi-arid Northeast Brazil often experiences periodic droughts, complicating water availability and quality for agriculture. Irrigated agriculture in this region faces the dual challenge of securing sufficient water and ensuring it is of adequate quality. Historically, water quality has been less of a concern due to the availability of better-quality water sources. However, as traditional water sources diminish, there's a growing need to consider lower-quality alternatives, including domestic sewages, industrial effluents and brackish waters.

Using saline water for irrigation can pose significant risks to bell pepper crops. High salt concentrations in irrigation water can lead to salt stress in plants, affecting their growth, development, and overall yield. Salt stress primarily impacts plants by disrupting water absorption, nutrient uptake, and photosynthetic efficiency. Plants in saline environments struggle to absorb water because the high salt concentration increases the osmotic pressure, making it harder for roots to extract water from the soil. Additionally, excessive salt accumulation can lead to ion toxicity and nutrient imbalances within plant tissues.

Combating Salt Stress: Key Findings on Bell Pepper Cultivars

A study conducted at the Federal University of Campina Grande in Paraíba, Brazil, evaluated the tolerance of five bell pepper cultivars to salt stress during the seedling stage. The experiment assessed the impact of varying salinity levels in irrigation water on plant growth, emergence, and biomass accumulation. The bell pepper cultivars—Dulce All Big (C1), All Big (C2), Italiano Amarelo Gigante (C3), Rubi Gigante (C4), and Casca Dura Ikeda (C5)—were subjected to five levels of salinity ranging from 0.6 dS m⁻¹ (control) to 3.0 dS m⁻¹.

Practical Implications and Future Directions

Selecting salt-tolerant cultivars like 'All Big' and 'Rubi Gigante' is crucial for maintaining bell pepper yields in areas affected by water salinity. These cultivars can withstand higher salt concentrations, ensuring better crop performance and reduced yield losses. Implementing efficient irrigation practices, such as drainage lysimetry and leaching fractions, helps manage soil salinity. By maintaining optimal soil moisture and preventing salt buildup, growers can minimize the negative impacts of saline water. As water scarcity and quality issues intensify, ongoing research into salt-tolerant crops and effective salinity management techniques will become increasingly important for sustainable agriculture. These efforts will support food security and economic stability for farmers in salt-affected regions.