Effect of leaf surface wetness and wettability on photosynthesis in bean and pea

Abstract

Leaf surface wetness that occurs frequently in natural environments has a significant impact on leaf photosynthesis. However, the physiological mechanisms for the photosynthetic responses to wetness are not well understood. The responses of leaf CO 2 assimilation rate ( A ) to 72 h of artificial mist of a wettable (bean; Phaseolus vulgaris ) and a non-wettable species (pea; Pisum sativum ) were compared. Stomatal and non-stomatal limitations to A were investigated. A 28% inhibition of A was observed in the bean leaves as a result of a 16% decrease in stomatal conductance and a 55% reduction in the amount of Rubisco. The decrease of Rubisco was mainly due to its partial degradation. In contrast to the bean leaves, a 22% stimulation of A was obtained in the 72 h mist-treated pea leaves. Mist treatment increased stomatal conductance by 12.5% and had no effect on the amount of Rubisco. These results indicated that a positive photosynthetic response to wetness occurred only in non-wettable species and is due to the change in stomatal regulation.

A Preliminary Experiment on the Effects of Leaf Wetting on Gas Exchange in Tomato Leaves

“…Therefore, interest in the positive effects of leaf wetting is limited for horticultural crops, despite many reports of these positive effects in natural environments (Limm et al, 2009) and a few reports in horticultural crops (Ozawa, 1988). Leaf wetting may have either positive or negative effects on horticultural crops, depending on plant water status (Cassana and Dillenburg, 2013;Cassana et al, 2016) and leaf morphology (Hanba et al, 2004). Because of the complexity of the effects of leaf wetting on plants, the application of its positive effects to horticultural crop cultivation are not currently fully understood.…”

Variation in Leaf Surface Hydrophobicity of Wetland Plants: the Role of Plant Traits in Water Retention

“…Leaf wetting further affects numerous ecological processes, such as photosynthesis rate (Hanba et al 2004), pathogen infection (Rowlandson et al 2015) or absorption and removal of pollutants (Neinhuis and Barthlott 1997). Plant ability to repel water from the leaf surface can be termed as its hydrophobicity and can be comprehensively described by measuring the contact angle (CA) between a water droplet and the leaf surface (Bradley et al 2003).…”

Wettability, Polarity, and Water Absorption of Holm Oak Leaves: Effect of Leaf Side and Age

“…Such surface features together with their chemical composition (Khayet and Fernández, 2012) may lead to a high degree of roughness and hydrophobicity (Koch and Barthlott, 2009;Konrad et al, 2012). The interactions of plant surfaces with water have been addressed in some investigations (Brewer et al, 1991;Brewer and Smith, 1997;Pandey and Nagar, 2003;Hanba et al, 2004;Dietz et al, 2007;Holder, 2007aHolder, , 2007bFernández et al, 2011Fernández et al, , 2014Roth-Nebelsick et al, 2012;Wen et al, 2012;Urrego-Pereira et al, 2013) and are a topic of growing interest for plant ecophysiology (Helliker and Griffiths, 2007;Aryal and Neuner, 2010;Limm and Dawson, 2010;Kim and Lee, 2011;Berry and Smith, 2012;Berry et al, 2013;Rosado and Holder, 2013;Helliker, 2014). On the other hand, the mechanisms of foliar uptake of water and solutes by plant surfaces are still not fully understood (Fernández and Eichert, 2009;Burkhardt and Hunsche, 2013), but they may play an important ecophysiological role (Limm et al, 2009;Johnstone and Dawson, 2010;Adamec, 2013;Berry et al, 2014).…”