Location: Plant Science ResearchTitle: Physiological basis for controlling water consumption by two snap beans genotypes using different anti-transpirants
|ABDALLAH, AHMED - Damanhour University|
|MASHAHEET, ALSAYED - Damanhour University|
|ZOBEL, RICHARD - North Carolina State University|
Submitted to: Agricultural Water Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/28/2018
Publication Date: 1/9/2019
Citation: Abdallah, A., Mashaheet, A., Zobel, R., Burkey, K.O. 2019. Physiological basis for controlling water consumption by two snap beans genotypes using different anti-transpirants. Agricultural Water Management. 314:17-27.
Interpretive Summary: Rainfall patterns have become more variable in recent years as a result of climate change, with severe and unpredictable drought and flooding that impact agricultural production. Furthermore, water is becoming a limited resource in many agricultural areas worldwide. Technologies that reduce water use while maintaining yield will be crucial for retaining soil moisture during the growing season and minimizing the use of irrigation water. In this study, a team of researchers from Egypt, North Carolina State University, and USDA-ARS tested the ability of anti-transpirant chemicals to reduce water use by snap bean plants. Greenhouse trials compared three different classes of chemicals, each class targeting a different physical or metabolic mechanism to reduce leaf transpiration and potentially reduce plant water use. The most effective anti-transpirant was kaolin clay, a white reflective material that reduced leaf temperature. A 4% kaolin suspension applied to leaf surfaces reduced water consumption by 26% and 13%, respectively, for two different snap bean genotypes. The results suggest that anti-transpirant chemicals are a viable approach to reduce water usage by crops.
Technical Abstract: Water shortage is a serious environmental stress that influences crop productivity, will be common under climate change. Therefore, enhancing water use efficiency (WUE) while maintaining crop productivity represents a big challenge. The objectives of this study were to determine the effect of anti-transpirant (ATs) on the quantity and patterns of water consumption (WC), thus WUE, of well-irrigated two snap bean genotypes differing in ozone sensitivity [resistant (R123) and sensitive (S156)], in addition to studying their root and shoot physiological responses. Under glasshouse conditions, the two genotypes were sprayed with 4% kaolin (KPF), 0.0015% Fulvic acid (FA) or 1% Pinolene (P), as a reflective, metabolic inhibitor, or film forming ATs, respectively, whereas control plants were sprayed with water. Plants were subjected to three irrigation/drying cycles, then exposed to survivability tests by ceasing irrigation. Water consumption, some physiological parameters, plant survivability and root development were determined. The results showed minimal genotype effects on all tested parameters, except total dry matter (TDM), dry matter accumulation rate (DMAR), and fine root diameter and length. Leaves of KPF-treated plants were significantly cooler than the control (3.65°C), consequently, had lower leaf water potential and WC, without effecting TDM or DMAR. Therefore, WUEp was increased by 26.35% and 13.02% for R123 and S156 genotypes, respectively. However, P and FA treatment had no significant effects on these parameters. The use of KPF alleviated most physiological effects of water deficit, hence, KPF-treated plants survived longer. Plants treated with KPF and FA had thicker very fine and fine roots than the controls, with KPF having the strongest effect. Pinolene treatment had no effect on the roots of the ozone-resistant line, but conditioned significant root thickening of the ozone-sensitive line.