Finding Needles in a Haystack: Using Geo-References to Enhance the Selection and Utilization of Landraces in Breeding for Climate-Resilient Cultivars of Upland Cotton (Gossypium hirsutum L.)

Abstract

The genetic uniformity of cultivated cotton as a consequence of domestication and modern breeding makes it extremely vulnerable to abiotic challenges brought about by major climate shifts. To sustain productivity amidst worsening agro-environments, future breeding objectives need to seriously consider introducing new genetic variation from diverse resources into the current germplasm base of cotton. Landraces are genetically heterogeneous, population complexes that have been primarily selected for their adaptability to specific localized or regional environments. This makes them an invaluable genetic resource of novel allelic diversity that can be exploited to enhance the resilience of crops to marginal environments. The utilization of cotton landraces in breeding programs are constrained by the phenology of the plant and the lack of phenotypic information that can facilitate efficient selection of potential donor parents for breeding. In this review, the genetic value of cotton landraces and the major challenges in their utilization in breeding are discussed. Two strategies namely Focused Identification of Germplasm Strategy and Environmental Association Analysis that have been developed to effectively screen large germplasm collections for accessions with adaptive traits using geo-reference-based, mathematical modelling are highlighted. The potential applications of both approaches in mining available cotton landrace collections are also presented.

Stem transcriptome screen for selection in wild and cultivated pitahaya (Selenicereus undatus): an epiphytic cactus with edible fruit

“…These cellular reactions have been documented in several cultivated plants such as barley, in which drought-tolerant cultivars modify auxin transport and ethylene signaling, resulting in a better redistribution of assimilates ( Hong, Ni & Zhang, 2020 ; Qiu et al, 2020 ). Furthermore, evidence of selection of drought-resistance genes has been documented in cultivated plants such as weedy rice ( Han et al, 2022 ), cotton ( Shim, Bandillo & Angeles-Shim, 2021 ) and moth bean ( Yundaeng et al, 2019 ). Thus, the enrichment of genes found in the cultivated plants of pitahaya might be related to the response to drought.…”

Bottom-up perspective – The role of roots and rhizosphere in climate change adaptation and mitigation in agroecosystems

“…Future approach to breeding crops with better root systems In order to better understand the mechanisms and evolutionary effects underlying 'crop species' adaptation to environmental stress, large-scale genomic, phenomic, and ecological data must be combined (Li et al 2019;Shim et al 2021;Al-Hajaj et al 2022). Likewise, such approaches can focus on mitigation of climate change with emphasis on carbon sequestration to soils and optimising the nitrogen cycle in the rhizosphere.…”

Heritage genetics for adaptation to marginal soils in barley

“…Illustration by Debbie Maizels, Zoobotanica Scientific Illustration. range of crop species [60][61][62]. The use of geographic and agroecological information and past and future climate-predictive modelling, along with crop simulation and trait-based ensemble modelling, can focus the search for stress tolerance genes and provide support for environmental ideotype breeding [43,[63][64][65].…”