Morpho-physiological responses of chili peppers (Capsicum annuum) to short-term exposure of water-saturated rhizosphere

Abstract

Chili pepper is frequently grown by local farmers at riparian wetland during dry season in Indonesia. However, during the last decade, unpredictable distribution and intensity of rainfall have increasingly threatened chili pepper production at the wetlands due to untimely water-saturated rhizosphere (WSR) occurrences. WSR is a condition when all pores within root zone were filled with water. This condition can be simulated by adding water into growing substrate until a thin layer of water was visible above substrate surface. Two Indonesian varieties (Laris and Romario) and one Japanese variety (Takanotsume) were used in this study. Aim of this study was to evaluate morpho-physiological effects of short-term (4 days) WSR exposure in chili pepper. Results of this study revealed that roots suffered more than aerial organs as indicated by the increase of shoot/root ratio from 4.56 at pre-exposure to 7.03 at end of the exposure. Total leaf area significantly reduced since larger older leaves were replaced by newly developed smaller leaves. Relative water content (RWC) in all organs was decreased, but did not reach a detrimental level. Leaf RWC was decreased from 83.6% at pre-exposure to 77.8% after the exposure; however, leaf RWC was able to rebound to 81.5% after 7 days of recovery. Photosynthetic and transpiration rates sharply decreased, associated with decrease in stomatal conductance during WSR exposure. Chlorophyll fluorescence also sharply declined. Gas exchange parameters did not significantly recover after 7 days of recovery in all varieties. Meanwhile, SPAD values were not affected by WSR exposure.

Growth and morpho-physiological assessments of Indonesian red chili cultivars on early vegetative stage under water stress conditions: A comparison of waterlogging and drought

“…Waterlogging and drought stress were contrasting abiotic stresses. Waterlogging stress generally causes adverse effects on plant morphoagronomic and physiological traits (Ichsan et al, 2021), including a decrease in the rate of plant leaf expansion (Meihana et al, 2023) and root expansion (Siaga et al, 2023), changes in leaf color/reduced leaf chlorophyll content (Zainul et al, 2022), adventitious root formation (Pandey et al, 2021), and decreased plant dry weight (Siaga et al, 2019b). On the other hand, plants also respond to drought stress by slowing growth and photosynthetic activity (Widuri et al, 2018; and increasing proline accumulation (Avramova et al, 2016).…”

Influence of growing systems and non-fertilizer ameliorants on microclimate and growth of Brazilian spinach

“…Some cultivars have also exhibited a robust performance under the floating growing system, such as water spinach, lettuce and rocket (Guo et al 2019, Miceli et al 2019. Meanwhile, other cultivars, including celery (Lakitan et al 2021a) and chili pepper (Siaga et al 2019a), have adapted well to the bottom-wet growing system.…”

Acclimating leaf celery plant (Apium graveolens) via bottom wet culture for increasing its adaptability to tropical riparian wetland ecosystem

“…In a flat landscape like in riparian wetlands, this shallow water condition can cover significant acreages. Many terrestrial vegetable crops have shown their adaptability to this transitional zone (Siaga et al 2019;Susilawati and Lakitan 2019;Lakitan et al 2018b;Meihana et al 2017). Leaf celery could be another candidate for enriching diversity of vegetables cultivated at tropical riparian wetlands.…”