Germination response of diverse wild and landrace chile peppers (Capsicumspp.) under drought stress simulated with polyethylene glycol

Abstract

<jats:title>Abstract</jats:title><jats:p>Responses to drought within a single species may vary based on plant development stage, drought severity, and the avoidance or tolerance mechanisms employed. Early drought stress can restrict emergence and seedling growth. Thus, in areas where water availability is limited, rapid germination leading to early plant establishment may be beneficial. Alternatively, germination without sufficient water to support the seedling may lead to early senescence, so reduced germination under low moisture conditions may be adaptive at the level of the population. We studied the germination response to osmotic stress of diverse chile pepper germplasm collected in southern Mexico from varied ecozones, cultivation systems, and of named landraces. Drought stress was simulated using polyethylene glycol solutions. Overall, survival time analysis revealed delayed germination at the 20% concentration of PEG across all ecozones. The effect was most pronounced in the genotypes from hotter, drier ecozones. Additionally, accessions from wetter and cooler ecozones had the fastest rate of germination. Moreover, accessions of the landraces <jats:italic>Costeño Rojo</jats:italic> and <jats:italic>Tusta</jats:italic> germinated more slowly and incompletely if sourced from a drier ecozone than a wetter one, indicating that slower, reduced germination under drought stress may be an adaptive avoidance mechanism. Significant differences were also observed between named landraces, with more domesticated types from intensive cultivation systems nearly always germinating faster than small-fruited backyard- or wild-types, perhaps due to the fact that the smaller-fruited accessions have generally undergone less selection. Thus, we conclude that there is evidence of local adaptation to both ecozone of origin and source cultivation system in germination characteristics of diverse chile peppers.</jats:p>

Environment of origin and domestication affect morphological, physiological, and agronomic response to water deficit in chile pepper (Capsicum sp.)

“…originating from low precipitation environments may possess elevated tolerance to soil water deficit. For example, a recent germination study identified adaptive responses in chile pepper associated with precipitation [15]. Landraces from hotter, drier ecozones had significantly delayed germination, suggesting a possible adaptive response related to drought avoidance.…”

Environment of origin and domestication affect morphological, physiological, and agronomic response to water deficit in chile pepper (Capsicum sp.)

“…However, this reduction in PBr with breeding is also reflected in our data where improved, US accessions had lower PBr. Bernau [ 18 ], using landraces from southern Mexico, indicated that PBr may relate to environmental adaptation. In her work, PBr was lower in chile pepper accessions from the wet, western coast of Oaxaca and higher in accessions from the drier ecozones, Eastern Oaxaca and the Yucatan peninsula, reinforcing our results.…”

“…We chose the seven Mexican accessions from an array of chile peppers collected from diverse environments in the Mexican state of Oaxaca as potential sources of tolerance to water deficit based on a combination of their environment of origin, performance in a prior greenhouse study, and results from an environmental association analysis that used environment of origin as a “phenotype” [ 18 ]. In addition to their possible drought adaptations, the seven accessions serve as parents in on-going population development for continued genetic studies.…”

Designing Climate-Smart Brinjal That Can Withstand a Variety of Environmental Conditions: A Perspective

“…Sometimes the eggplant fruits are less developed or show smaller sizes compared to the actual size of the fruit. Under such circumstances sowing of crop in the late season or using heat tolerant hybrids as an alternative is advised under traditional breeding methods to reduce the damages caused by high temperature conditions [67].…”

“…In certain rainfall areas the plants show certain rotting symptoms where the fruits of the eggplants become soft and oozes water from inside. In such cases of low temperatures and rainfall conditions the crops are sown in the later season, mixed cropping is employed sometimes or growing of the eggplants in green houses under controlled environmental conditions is the possible way to fix the changes in the climate [67].…”