Irrigation restriction effects on water use efficiency and osmotic adjustment in Aloe Vera plants ( Aloe barbadensis Miller)

• Published in: Agricultural water management Vol. 97; no. 10; pp. 1564 - 1570
• Main Authors: Delatorre-Herrera, J., Delfino, I., Salinas, C., Silva, H., Cardemil, Liliana
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.2010; Amsterdam; New York: Elsevier; Elsevier
• Series: Agricultural Water Management
• Subjects: Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agronomy. Soil science and plant productions; Aloe barbadensis; Aloe vera; Biological and medical sciences; Field capacity; Field capacity Water use efficiency (WUE) Osmotic adjustment Sap flow rate Fructans; Fructans; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; irrigation management; irrigation restriction; osmoregulation; Osmotic adjustment; Physical properties; Physics, chemistry, biochemistry and biology of agricultural and forest soils; plant-water relations; sap flow; Sap flow rate; Soil science; soil water; soil water deficit; Water and solute dynamics; water use efficiency; Water use efficiency (WUE); Sap flow rate; Fructans; Water use efficiency (WUE); Osmotic adjustment; Field capacity; Irrigation; Monocotyledones; Sap; Homopolyoside; Medicinal plant; Internal flow; Angiospermae; Water engineering; Carbohydrate; Flow rate; Soil moisture; Biochemical compound; Property of soil; Osmoregulation; Oside; Water use efficiency; Physical properties; Liliaceae; Soil water properties; Fructosan; Spermatophyta; Aloe vera; Polysaccharide
• ISSN: 0378-3774; 1873-2283
• DOI: 10.1016/j.agwat.2010.05.008

Aloe barbadensis Miller, known as Aloe Vera, requires limited irrigation depending on the capacity of the soil to retain humidity, since it is a CAM species and thus naturally adapted to conditions of dryness and high temperatures. Therefore, we postulated that plants of Aloe Vera plants under conditions of water deficit should improve their water use efficiency (WUE) by performing osmotic adjustment (OA) with a temporal correlation between WUE and OA. The objective of the investigation was to determine the effect of water restriction on the WUE and OA of A. barbadensis under different water treatments. 18-month old Aloe Vera plants were cultivated in pots with a soil substrate that was a mixture of equal parts of sand and organic matter with 18% of FC and 9% of permanent wilting point. To determine the effects of the soil humidity on plant WUE and OA, four treatments were arranged in a complete random design with four repetitions; these were 100%, 75%, 50% and 25% of FC, which correspond to an evatranspiration of 11.4, 9.6, 4.0 and 1.7 L per plant, respectively. The water treatments were maintained by frequent irrigation. The following variables were determined: dry matter, leaf water potential, relative water content (RWC), amount of gel produced, sap flow, proline content, soluble and total sugars and oligo and polyfructans. Aloe Vera increased WUE with increasing water deficit; the sap flow rate decreased with water restrictions, and the plants performed osmotic adjustment by increasing the synthesis of proline, soluble and total sugars as well as the amounts of oligo and polyfructans, mainly polymers of β-(2 → 6) kestotriose, changing from the inulin type to the neofructan type. The plants most and less irrigated (100% and 25% of FC) were the groups with lowest WUE. The plants irrigated with 75% of FC presented the best WUE in terms of dry mass and amount of gel produced by a litre of supplied water.