|Amrhein, Christopher - U CALIF, RIVERSIDE, CA|
Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 14, 2005
Publication Date: February 10, 2006
Citation: Grieve, C.M., Poss, J.A., Amrhein, C. 2006. Response of Matthiola incana to Irrigation with Saline Wastewaters. HortScience. 41:119-123. Interpretive Summary: Competition between agricultural and urban users for high-quality water supplies has increased as the population has increased. One environmentally-sound approach to the conservation of these dwindling water resources is the reuse of degraded, often saline, wastewaters for crop production. Growers of high value cut flower crops have traditionally used high-quality waters in order to avoid yield losses associated with salinity. However, little quantitative information is available in the literature that would guide growers in the selection of cut flower species which could be produced with recycled, saline waters. This report describes the response of Matthiola incana (stock), a commercially valuable cut flower, to irrigation with waters prepared to simulate saline wastewaters commonly present in the inland valleys of California. Two varieties of stock (‘Cheerful White’ and ‘Frolic Carmine’) were grown in greenhouse sand tanks. Five salinity levels were imposed with electrical conductivities (ECiw) of 2, 6, 8, 11 and 14 dS/m. Neither variety showed visible symptoms or injury associated with salinity, ion toxicity or deficiency. Flower quality was rated on stem length and weight, stem diameter and numbers of flowers per inflorescence. Marketable flowers were produced in all treatments. At lower salinities (2, 6, and 8 dS/m flowers were rated as ‘premium’ and quality was reduced to ‘above average’ once ECiw exceeded 8 dS m-1. The results of this study clearly demonstrate that stock may be produced using saline waste waters without reduction of commercial acceptability nor loss of economic product.
Technical Abstract: Two cultivars of Matthiola incana (L.) R. Br. (‘Cheerful White’ and ‘Frolic Carmine’) were grown in greenhouse sand cultures to determine the effect of salt stress on growth, ion relations, and flower quality. Two types of irrigation waters, differing in ion composition, were prepared to simulate saline wastewaters commonly present in two inland valley locations in California. Solution ‘ICV’ was typical of saline ‘tailwaters’ frequently found in the Imperial and Coachella Valleys, and contained Cl-, Na+, SO42-, Mg2+, Ca2+, predominating in that order. Solution ‘SJV’ was dominated by sodium and sulfate and simulated saline drainage effluents often present in the San Joaquin Valley. Five treatments of each salinity type were imposed. Treatments were replicated three times. Electrical conductivities of the irrigation waters (ECi) were 2, 5, 8, 11, and 14 dS/m. Plant heights were determined weekly. Seedlings were sampled for ion analysis nine weeks after planting. Total stem length, weight and diameter, and inflorescence length were measured at final harvest. All plants remained healthy throughout the experimental period and with no visible signs of ion toxicity or deficiency. ). Flowering stalks were premium market quality until irrigation water salinity exceeded 8 dS/m. Reduction in stem length at higher salinities resulted in marketable stems of above average quality. Growth parameters were generally enhanced by irrigation with ICV waters, but this trend was not significant. Mineral ion composition of the vegetative tissues generally reflected ion concentrations in the irrigation waters. Shoot-Mg and -Cl were higher and shoot-Na and -S were lower in seedlings irrigated with ICV waters than with SJV waters. This study illustrates that selected cut flower species may be economically produced under irrigation with moderately saline wastewaters.