Response of leaf water potential, stomatal conductance and chlorophyll content under different levels of soil water, air vapor pressure deficit and solar radiation in chili pepper (Capsicum chinense)

• Published in: Scientia horticulturae Vol. 281; p. 109943
• Main Authors: Goto, Keita, Yabuta, Shin, Ssenyonga, Peter, Tamaru, Shotaro, Sakagami, Jun-Ichi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 30.04.2021
• Subjects: Capsicum chinense; Chili pepper; Crop growth model; Evapo-transpiration; Leaf senescence; Leaf stomatal conductance; Leaf water potential; Light-harvesting complex; Plant-environment interactions; Vegetable crop; Plant-environment interactions; Vegetable crop; Capsicum chinense; Leaf water potential; Evapo-transpiration; Leaf senescence; Leaf stomatal conductance; Chili pepper; Crop growth model; Light-harvesting complex
• ISSN: 0304-4238; 1879-1018
• DOI: 10.1016/j.scienta.2021.109943

•Chili pepper increased fallen leaves weight and decreased leaf area as responses to dry and waterlogged soil conditions.•Leaf chlorophyll content on chili pepper increased and their chlorophyll a/b ratio decreased in dry and water logged soil conditions.•Chlorophyll a/b ratio is available to evaluate stress level by soil water, vapor pressure deficit and solar radiation.•A regression model for estimating shoot dry weight (SDW) from plant height (PH) and SPAD value (SPAD) was developed. The model (SDW = 0.131 PH + 0.047SPAD − 2.408, R2adj = 0.836). Flood and drought have been increasing due to global climate changes and these extreme water-related events often affect crop productions globally. This study aims to develop a growth simulation model that correspond to sequential soil water status by revealing morph-physiological related responses on the chili pepper (Capsicum spp.). Two experiments were conducted in a greenhouse and nine treatments were established between dry and waterlogged soil conditions by using a slope field with sand. Results showed leaf water potential and stomatal conductance decreased with increasing soil water stress level. On the other hand, chili pepper increased total chlorophyll content and decreased chlorophyll a/b ratio to compensate the redaction of the leaf area as a response to soil water stress. Moreover, high air vapor pressure deficit and solar radiation condition influenced their morph-physiological traits as environmental stress coupled with soil water stress. A multiple regression model for estimating shoot dry weight (SDW) using plant height (PH) and soil plant analysis development (SPAD) was developed (SDW = 0.131 PH + 0.047SPAD − 2.408). It showed a high coefficient of determination (R2adj = 0.836). This model is certainly useful for estimating SDW under wide range soil water statuses and vapor pressure deficit conditions.