The potential of antitranspirants in drought management of arable crops: A review

Abstract

About 80% of global farmland is under rain-fed conditions and most of it prone to drought, which limits crop productivity. Due to climate change, drought will become more frequent and severe threatening world food security.Antitranspirants, materials that reduce transpiration, could potentially result in greater food production by realising more of a crop's potential yield during drought. Despite antitranspirants also reducing photosynthesis, research has shown that they can mitigate drought stress resulting in increased grain yield.Although this paper is not restricted to specific years, part of it is a systematic review of 173 original research articles published between 2009 and 2018.Overall, the analysis suggests that interest in the potential of antitranspirants is growing.One major achievement in antitranspirant research during the past decade was establishing the optimal timing of application of the substances, which is linked to reproductive processes most vulnerable to drought. Despite research evidence of the efficacy of antitranspirants in ameliorating drought stress, they are not widely used for commercial arable crop production. However, in fruit horticulture, 2 products with antitranspirant effects are being used for various non-antitranspirant purposes such as synchronising fruit ripening, enhancement of nutritional quality, protection against sunburn and controlling diseases and insect pests.

Leaf Wax Extracted from Cauliflower Waste Shows Antitranspirant Efficacy

“…Six types of brassica (all B. Oleracea L.) waste were sourced by Freshtime: cauliflower leaves, spring green cabbage leaves, broccoli flower heads, savoy cabbage leaves, broccoli stems, green cabbage leaves. Approximately 30 g of each brassica waste were immersed in 50 cm 3 dichloromethane for 24 hours and the dichloromethane was subsequently removed in vacuo and wax yield determined.…”

“…One little-used technology is the retardation of water vapour loss from stomata on the leaves of crop plants by application of polymers, referred to as film antitranspirants (ATs) in this context. These polymers are used on ornamental plants, but not yet widely-used on major food crops [3].…”

“…wheat [4,5] rapeseed [6]. Appropriately-timed AT applications under drought have been previously associated with enhanced water saving strategies, lowered abscisic acid accumulation and increase in leaf intrinsic water use efficiency [3,4,5,6] leading to sustained key yield components under distinct reduced water availability patterns [3,6]. However, the current commercially-available film AT products are expensive and a cheaper film AT is needed to facilitate use in crop production.…”

Characterizing the Efficacy of a Film-Forming Antitranspirant on Raspberry Foliar and Fruit Transpiration

“…Aside from the implementation of deficit irrigation strategies (concomitant with vigilant monitoring of plant water status), improvements in the efficiency of water-use can be achieved through the foliar application of antitranspirants [13,14]. These antitranspirants can be natural or synthetic, and may form a protective barrier [15], reflect sunlight and lower leaf temperature [16] or induce guard cell closure [17].…”

“…These antitranspirants can be natural or synthetic, and may form a protective barrier [15], reflect sunlight and lower leaf temperature [16] or induce guard cell closure [17]. Antitranspirants have had positive effects on plant performance in strawberry, gooseberry, kiwi, tomato, apple, banana, mango and other fruits when exposed to drought [14]). Di-1-p-menthene (pinolene) is a distillate from conifer resin and used as a film-forming antitranspirant that seals vulnerable tissues and curtails dehydration [18].…”