Drought stress is a major abiotic factor limiting global crop productivity by disrupting cellular homeostasis, impairing photosynthesis, and restricting metabolic activity. Plant-associated microorganisms, including rhizobacteria, endophytes, and arbuscular mycorrhizal fungi, play key roles in enhancing drought resilience through molecular, biochemical, and physiological mechanisms. These beneficial microbes modulate phytohormone biosynthesis, enhance osmolyte accumulation, increase organic acid exudation, and activate ROS-scavenging antioxidant pathways. Microbe-mediated regulation of aquaporins, heat shock proteins, and root system architecture further improves water-use efficiency, hydraulic conductance, and stress acclimation. Advances in microbial genomics and systems biology have revealed the molecular drivers of plant–microbe synergism, enabling the development of tailored microbial consortia and next-generation bioinoculants. Complementarily, genetic and genome-guided modulation of drought-responsive regulatory hubs including transcription factors (e.g., DREBs, NACs, MYBs, and bZIPs), signal transducers (e.g., MAPKs and CDPKs), and protective proteins enhances adaptive plasticity under water deficit conditions. This review integrates current molecular insights into drought-induced perturbations in plants and highlights the convergence of microbial interventions and genome-guided strategies in reinforcing drought tolerance. Emphasizing mechanistic frameworks, scalable microbial technologies, and molecular breeding approaches, this work underscores their potential to improve crop resilience in increasingly water-limited environments.

In recent years, the economic impact of the grape and wine industry within Texas has significantly increased. The majority of grapes grown in Texas are produced within the Texas High Plains American Viticultural Area (AVA). Vineyards within this AVA are subject to late spring frosts that may potentially reduce crop yields, and lower fruit quality. Objectives of this experiment were to compare the growth and fruitfulness of shoots grown from primary and secondary buds of V. vinifera ‘Grenache’ vines grafted onto three rootstocks (110 R, 1103P, and Freedom). Over two growing seasons, field-grown vines were exposed to the following treatments: primary bud growth and forced secondary bud growth (simulated late spring frost). Leaf gas exchange, pruning cane weight, vine yield, and fruit maturity data were collected each year. Bud treatment or rootstock did not influence leaf gas exchange. Cane weight and yield data were greater for shoots grown from primary bud shoots, and rootstock 1103P. In addition, berries grown from primary buds and 1103P rootstocks were more mature compared to fruits from secondary buds or vines grown on other rootstocks. Results offer insight into the potential interaction of ‘Grenache’ scions with grafted rootstocks during a late spring frost within the Texas High Plains AVA.

Use of leaf gas exchange measurement enhances the characterization of growth, yield, physiology, and abiotic stress response in grapevines. Accuracy of a crop response model depends upon sample size, which is often limited due to the prolonged time needed to complete gas exchange measurement using currently available infra-red gas analyzer systems. In this experiment, we measured mid-day gas exchange of excised and in situ leaves from field grown wine grape (Vitis vinifera) cultivars. Depending upon cultivar, we found measuring gas exchange on excised leaves under a limited time window post excision gives similar accuracy in measurement of gas exchange parameters as in situ leaves. A measurement within a minute post leaf excision can give between 96.4 and 99.5% accuracy compared to pre-excision values. When compared to previous field data, we found the leaf excision technique reduced time between consecutive gas exchange measurements by about a third compared to in situ leaves (57.52 ± 0.39 s and 86.96 ± 0.41 s, for excised and in situ, respectively). Therefore, leaf excision may allow a 50% increase in experimental sampling size. This technique could solve the challenge of insufficient sample numbers, often reported by researchers worldwide while studying grapevine leaf gas exchange using portable gas exchange systems under field conditions.

Due to challenges associated with lavender propagation, Texas hybrid lavender (lavandin) growers require revised propagation information. Therefore, experiments investigated effects of media and plant growth regulators (PGR) on rooting of three different lavandin (Lavandula x intermedia) cultivars. PGRs applied to cuttings were naphthaleneacetic acid (NAA), or indole-3-butyric acid (IBA) at three concentrations. In addition, four rooting media were examined. Cuttings exposed to a peat moss/sand medium had the greatest mean overall rooting percentage, number of roots, and regardless of cultivar, cuttings exposed to the peat moss/sand medium had the longest roots. In general, mean rooting data were also greatest for cuttings dipped in NAA at 0.5 and 1.0 g·L⁻¹ (500 and 1000 ppm, respectively). Overall, across all media and PGR treatments ‘Grosso' cuttings tended to have the greatest rooting percentage and longest roots. In addition, compared to the no PGR treatment, ‘Provence' and ‘Hidcote Giant' cuttings exposed to the peat moss/sand medium and greater PGR concentrations produced cuttings with an increased mean rooting percentage and longer roots. When rooting lavandin cultivars, results indicate correct media selection, PGR formulation, and PGR concentration determine propagation success. Index words: lavandin, Lavandula x intermedia Emeric ex Loisel, peat moss, perlite, rooting percentage, root quality, sand. Chemicals used in this study: indole-3-butyric acid (IBA; 0.5, 1.0, and 1.5 g^.L⁻¹); naphthaleneacetic acid (NAA; 0.5, 1.0, and 1.5 g^.L⁻¹). Species used in this study: ‘Grosso', ‘Provence', and ‘Hidcote Giant' lavandin (Lavandula x intermedia Emeric ex Loisel.).

Gas exchange and growth of transplanted and nontransplanted, mulched and nonmulched field-grown Shumard red oak trees ( Quercus shumardii Buckli.) were investigated in a semiarid climate. In Spring 2003, 12 field-grown trees were selected for uniformity. Six trees were moved with a tree spade and six trees were undisturbed. In addition, pine bark mulch was applied around three randomly selected transplant and nontransplant trees. Soil volumetric water content, predawn leaf water potential, midday stomatal conductance ( g _S ) and leaf temperature, and growth data were collected over three consecutive growing seasons. Throughout the experiment, weekly predawn leaf water potential and g _S data indicate transplanted trees with and without mulch were under greater water stress when compared with nontransplanted trees. In addition, nontransplanted trees with mulch were under greater stress when compared with nontransplanted trees without mulch. Each year, transplanted trees and nontransplanted trees with mulch had less apical growth when compared with nontransplanted trees without mulch. Although gas exchange and apical growth of transplanted trees and nontransplanted mulched trees tended to increase each growing season, by experiment termination, gas exchange and apical growth for transplanted trees and nontransplanted trees with mulch did not recover to nontransplanted, nonmulch tree levels.