Use of Non-Destructive Measurements to Identify Cucurbit Species (Cucurbita maxima and Cucurbita moschata) Tolerant to Waterlogged Conditions

Abstract

Limited information is available regarding the physiology of squash plants grown under waterlogging stress. The objectives of this study were to investigate the growth and physiological performances of three cucurbit species, Cucurbita maxima cultivar (cv.) OK-101 (OK) and Cucurbita moschata cv. Early Price (EP) and Strong Man (SM), in response to waterlogging conditions, and to develop a precise, integrated, and quantitative non-destructive measurement of squash genotypes under stress. All tested plants were grown in a growth chamber under optimal irrigation and growth conditions for a month, and the pot plants were then subjected to non-waterlogging (control) and waterlogging treatments for periods of 1, 3, 7, and 13 days (d), followed by a 3-d post-waterlogging recovery period after water drainage. Plants with phenotypes, such as fresh weight (FW), dry weight (DW), and dry matter (DM) of shoots and roots, and various physiological systems, including relative water content (RWC), soil and plant analysis development (SPAD) chlorophyll meter, ratio of variable/maximal fluorescence (Fv/Fm), quantum photosynthetic yield (YII), normalized difference vegetation index (NDVI), and photochemical reflectance index (PRI) values, responded differently to waterlogging stress in accordance with the duration of the stress period and subsequent recovery period. When plants were treated with stress for 13 d, all plants exhibited harmful effects to their leaves compared with the control, but EP squash grew better than SM and OK squashes and exhibited stronger tolerance to waterlogging and showed less injury. Changes in the fresh weight, dry weight, and dry matter of shoots and roots indicated that OK plants suffered more severely than EP plants at the 3-d drainage period. The values of RWC, SPAD, Fv/Fm, YII, NDVI, and PRI in both SM and OK plants remarkably decreased at waterlogging at the 13-d time point compared with controls under identical time periods. However, the increased levels of SPAD, Fv/Fm, YII, NDVI, and PRI observed on 7 d or 13 d of waterlogging afforded the EP plant leaf with improved waterlogged tolerance. Significant and positive correlations were observed among NDVI and PRI with SPAD, Fv/Fm, and YII, indicating that these photosynthetic indices can be useful for developing non-destructive estimations of chlorophyll content in squashes when screening for waterlogging-tolerant plants, for establishing development practices for their cultivation in fields, and for enhanced cultivation during waterlogging in frequently flooded areas.

Short waterlogging events differently affect morphology and photosynthesis of two cucumber (Cucumis sativus L.) cultivars

“…Waterlogging induces significant changes in the photosynthetic performance of C3 crops, especially in sensitive plants like cucurbits (He et al, 2018;Barickman et al, 2019;Lin et al, 2020). This response was evident in the current study as A, g s , and E for the two cultivars after 10 DOW treatments were 10.3389/fpls.2022.896244 significantly reduced.…”

“…The substantial decline in the rate of photosynthesis is another characteristic feature of plants subjected to waterlogging conditions. Previous studies have demonstrated the sensitivity of photosynthesis in many crops, including cucumber (Barickman et al, 2019), squash (Lin et al, 2020), tomato (Bhatt et al, 2015), and watermelon (Yetisir et al, 2006). For instance, within the first day of waterlogging treatment, cucumber plants' CO 2 assimilation rate (A) rate declined rapidly (Kang et al, 2009;Barickman et al, 2019).…”

Waterlogging induces alterations in cucumber ( Cucumis sativus L.) photosynthesis, chlorophyll fluorescence, and responses to CO 2 and light intensity.

“…Waterlogging induces significant changes in the photosynthetic performance of C3 crops, especially in sensitive plants like cucurbits (He, Yu, Li, Du & Guo 2018;Barickman et al 2019;Lin et al 2020). This response was evident in the current study as A, g s , and E for the two cultivars after 10 DOW treatments were significantly reduced.…”

“…The substantial decline in the rate of photosynthesis is another characteristic feature of plants subjected to waterlogging conditions. Previous studies have demonstrated the sensitivity of photosynthesis in many crops, including cucumber (Barickman, Simpson & Sams 2019), squash (Lin, Lin, Huang & Su 2020), tomato (Bhatt et al 2015), and watermelon (Yetisir, C ¸aliskan, Soylu & Sakar 2006). For instance, within the first day of waterlogging treatment, cucumber plants' CO 2 assimilation rate (A) rate declined rapidly (Kang, Guo, Li & Duan 2009;Barickman et al 2019).…”

Mycorrhizal fungi enhance flooding tolerance of peach through inducing proline accumulation and improving root architecture

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Flooding, a kind of abiotic stress, causes serious harm to plant growth and development by interfering a series of physiological and biochemical activities of plants, finally resulting in the death of the plant. Under flooded conditions, the roots of plants completely soak in the soil of saturated water, inducing low oxygen or the anaerobic environment in the rhizosphere, leaching of mineral elements, and anaerobic respiration, which is not good for the plant growth (Lin et al 2020). Peach is a widely cultivated, deciduous fruit tree in the world.

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