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Basin big sagebrush (Artemisia tridentata subsp. tridentata) is a keystone species of the sagebrush steppe, a widespread ecosystem of western North America threatened by climate change. The study’s goal was to develop an in vitro method of propagation for this taxon to support genome sequencing and genotype-by-environment research on drought tolerance. Such research may ultimately facilitate the reintroduction of big sagebrush in degraded habitats. Seedlings were generated from two diploid mother plants (2n = 2x = 18) collected in environments with contrasting precipitation regimes. The effects of IBA and NAA on rooting of shoot tips were tested on 45 individuals and 15 shoot tips per individual. Growth regulator and individual-seedling effects on percent rooting and roots per shoot tip were evaluated using statistical and clustering analyses. Furthermore, rooted shoot tips were transferred into new media to ascertain their continued growth in vitro. The results suggest that A. tridentata is an outbred species, as shown by individuals’ effect on rooting and growth. IBA addition was the most effective method for promoting adventitious rooting, especially in top-performing individuals. These individuals also have high survival and growth rates upon transferring to new media, making them suitable candidates for generating biomass for genome sequencing and producing clones for genotype-by-environment research.

The following protocol describes the ex vitro, hardening and acclimation of in vitro grown genetically identical plantlets (i.e. clones) of Artemisia tridentata ssp. tridentata (Asteraceae). The goal of this protocol is to create functional clonal lines of Artemisia tridentata to be used in genotype-by-environment (GxE) experiments. Overall, the protocol consists of the following four major steps and takes 16 weeks to complete on 11-16-week old in vitro plantlets: i) transfer in vitro plantlets from modified Murashige & Skoog (MMS) media to a sand and vermiculite soil mixture (4:1 ratio; hereafter referred to as sandy soil) in an enclosed, high humidity vessel to initiate plantlet establishment and root growth (four weeks); ii) gradually open vessels to initiate dropping of in vitro leaves and growth of functional leaves (four weeks) associated with decreased of humidity and increased gas exchange; iii) establishing a watering regime to promote and maintain growth of functional plantlets (six weeks) and iv) transfer plantlets into a more complex soil mixture (similar to natural conditions composed of sand, silt and vermiculite at 2:1.5:0.5 ratio; referred to as silt soil) in an open vessel to complete acclimation; especially hardening of the root system (two weeks or more depending on specific needs). Upon completion, the sagebrush plantlets will be exhibiting a similar phenotype as sagebrush seedlings. Finally, although optional, we are encouraging users to conduct stem xylem pressure measurements on acclimatized and well-watered plantlets prior to starting GxE experiments to evaluate their hydraulic conductivity and overall level of stress. When citing this protocol, please also cite the full paper.

The following protocol describes the ex vitro, hardening and acclimation of in vitro grown genetically identical plantlets (i.e. clones) of Artemisia tridentata ssp. tridentata (Asteraceae). The goal of this protocol is to create functional clonal lines of Artemisia tridentata to be used in genotype-by-environment (GxE) experiments. Overall, the protocol consists of the following four major steps and takes 16 weeks to complete on 11-16-week old in vitro plantlets: i) transfer in vitro plantlets from modified Murashige & Skoog (MMS) media to a sand and vermiculite soil mixture (4:1 ratio; hereafter referred to as sandy soil) in an enclosed, high humidity vessel to initiate plantlet establishment and root growth (four weeks); ii) gradually open vessels to initiate dropping of in vitro leaves and growth of functional leaves (four weeks) associated with decreased of humidity and increased gas exchange; iii) establishing a watering regime to promote and maintain growth of functional plantlets (six weeks) and iv) transfer plantlets into a more complex soil mixture (similar to natural conditions composed of sand, silt and vermiculite at 2:1.5:0.5 ratio; referred to as silt soil) in an open vessel to complete acclimation; especially hardening of the root system (two weeks or more depending on specific needs). Upon completion, the sagebrush plantlets will be exhibiting a similar phenotype as sagebrush seedlings. Finally, although optional, we are encouraging users to conduct stem xylem pressure measurements on acclimatized and well-watered plantlets prior to starting GxE experiments to evaluate their hydraulic conductivity and overall level of stress.

Severe drought conditions and extreme weather events are increasing worldwide with climate change, threatening the persistence of native plant communities and ecosystems. Many studies have investigated the genomic basis of plant responses to drought. However, the extent of this research throughout the plant kingdom is unclear, particularly among species critical for the sustainability of natural ecosystems. This study aimed to broaden our understanding of genome-to-phenome (G2P) connections in drought-stressed plants and identify focal taxa for future research. Bioinformatics pipelines were developed to mine and link information from databases and abstracts from 7730 publications. This approach identified 1634 genes involved in drought responses among 497 plant taxa. Most (83.30%) of these species have been classified for human use, and most G2P interactions have been described within model organisms or crop species. Our analysis identifies several gaps in G2P research literature and database connectivity, with 21% of abstracts being linked to gene and taxonomy data in NCBI. Abstract text mining was more successful at identifying potential G2P pathways, with 34% of abstracts containing gene, taxa, and phenotype information. Expanding G2P studies to include non-model plants, especially those that are adapted to drought stress, will help advance our understanding of drought responsive G2P pathways.