EL PASO, TX--Vibrantly colored ornamental chile peppers (Capsicum annuum) are popular bedding and container plants, especially in warmer climates. Known for their uniquely attractive fruit and compact, garden-friendly stature, ornamental chiles come in a wide range of varieties, many named in honor of the holiday that reflects the fruit’s color. For example, the chile fruit of 'NuMex Valentine's Day' starts green, and then changes from ivory to red. Rounded ivory pods change to orange on the 'NuMex St. Patrick's Day' variety, while fruits morph from ivory to a celebratory lemon yellow on 'NuMex Memorial Day' plants. Keeping consumers and retailers supplied with these captivating plants requires extensive research into breeding and production practices. Looking for ways to meet growing demands for ornamental chile plants while remaining environmentally responsible led researchers to study the salt tolerance of 10 varieties of ornamental chile peppers.
"Soil salinization is a global concern, especially in populated arid and semiarid regions," said Genhua Niu, Associate Professor of Environmental Horticulture at the Texas AgriLife Research Center at El Paso. Niu explained that as high-quality irrigation water becomes increasingly limited, horticultural and agricultural growers are being encouraged to find alternative water sources--such as municipal reclaimed water--for irrigating crops. Despite many environmental benefits, higher usage of reclaimed waters for irrigation has resulted in increased amounts of salts in soil and ground water, which in turn affects the growth and development of plants such as ornamental chiles.
Niu and researchers Pedro Osuna, Youping Sun, and Denise Rodriguez studied the salt tolerance of 10 varieties of chile pepper plants by irrigating mature plants with saline solutions and germinating seeds in saline substrate in a greenhouse. The team examined characteristics including seedling emergence, growth, and mineral nutrition of each pepper cultivar. Their study was published in the journal HortScience.
"The results from our experiments showed that 'NuMex Cinco de Mayo' and 'NuMex Thanksgiving' were the most salt-tolerant cultivars, whereas 'NuMex Christmas' and 'NuMex Memorial Day' were the least tolerant ones," Niu said. The authors determined that the other eight ornamental pepper cultivars used in the experiments were moderately salt tolerant. They said that these eight varieties could be irrigated with saline solution at specified application rates with "little reduction in aesthetical values".
The study contains practical guidelines for the ornamental chile market, guaranteeing that plant retailers and home garden enthusiasts will have continued access to the sizzling colors of these fiery gems.
The complete study and abstract are available on the ASHS HortScience electronic journal web site: http://hortsci.ashspublications.org/content/47/11/1653.abstract
Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at ashs.org
Seedling Emergence, Growth, and Mineral Nutrition of Ornamental Chile Peppers Irrigated with Saline Water
Genhua Niu, Pedro Osuna, Youping Sun, and Denise S. Rodriguez
HortScience 47:1653–1657. [Abstract][Full Text][PDF]