Hydraulic anatomy affects genotypic variation in plant water use and shows differential organ specific plasticity to drought in Sorghum bicolor

Genotypic variability and plasticity in hydraulic anatomy are not well-understood in herbaceous monocots. In this study, we used Sorghum bicolor, a monocotyledonous, tropical grass model, to understand whether differential plant water use is associated with xylem anatomy and if whole-plant xylem anatomy responds to water stress, justifying differential genotypic sensitivity to drought. In a greenhouse environment, we studied four sorghum genotypes that are known to genetically differ in growth and exhibit differential sensitivity to drought. Under well-watered scenario, transpiration variability and plant growth traits correlated with xylem anatomical traits at both the leaf and stem level, including xylem area and predicted xylem-specific hydraulic conductivity. High water use genotypes had inherently higher hydraulic capacity, but under drought, their transpiration declined at higher fractions of transpirable soil water (FTSW) and they showed greater plasticity in hydraulic anatomy. However, lower FTSW thresholds and modest anatomical changes were identified in the low water use genotypes with inherently lower hydraulic conductivity. Drought, induced modular phenotypic plasticity in hydraulic anatomy, whereby plasticity in leaf xylem traits was remarkably higher than stem xylem, while root xylem showed a reverse nature of vascular modification. Xylem traits were in agreement with phloem anatomy, irrespective of water regime. Our study indicates that hydraulic anatomy can be critical for herbaceous monocots in determining limits to plant water use and genotypic response to drought with implications on whole-plant functions and habitat ecology

Mapping of genomic regions associated with dwarfing and the determinate growth habit in horsegram (Macrotyloma uniflorum)

Horsegram (Macrotyloma uniflorum) - an important, self-pollinated food legume, however due to limited genomic and genetic resources the genetic improvement could not be achieved as compare to other major legumes. Our work aims at finding novel microsatellite markers and their use for the construction of a linkage map from 157 individuals of F9 recombinant inbred lines (RILs) of horsegram. The determinate growth habit and plant height are important traits for its suitability for different cropping systems. The genotypic data were generated by screening 2 395 molecular markers, of which 600 (25.05 %) polymorphic markers were selected. Two-hundred eighty-seven (287) markers were mapped on ten linkage groups (LGs) at a log of odds (LOD) of 3.5 straddling 796.76 cM with 2.78 cM of marker density. For the identification of the quantitative trait loci (QTLs), the phenotypic data recorded on the RILs for the plant height and growth habit were analysed using the statistical tools JoinMap®and Windows QTL cartographer, based on the composite interval mapping (CIM) technique. Across the ten linkage groups, we detected four QTLs (LOD ≥ 2.5) for four traits. All the traits were major QTLs as indicated by the percentage of phenotypic variance (PVE) (≥ 10%) that ranged from 13.5% to 40.3%, therefore, this is very important information which can be used in marker-assisted selection (MAS). The present genomic information generated in this orphan crop, thus, provides the base for genetic improvements by devising molecular breeding strategies

Regulation of Osmotic Balance and Increased Antioxidant Activities under Heat Stress in Abelmoschus esculentus L. Triggered by Exogenous Proline Application

Keeping in view the yield losses instigated by heat stress in several crops, we carried out an experiment to explore the curative effect of exogenous applications of proline on the morpho-physiological, biochemical, and water-related attributes of okra genotypes under high-temperature stress (controlled conditions). Four contrasting genotypes C1, C2, C3, and C4 heat tolerant and heat sensitive genotypes were selected from a diverse panel of okra genotypes (n = 100) to examine plant responses to high-temperature stress and exogenous application of proline. Four-week-old seedlings were subjected to heat stress by gradually increasing the temperature of a growth chamber from 28/22 °C to 45/35 °C (day/night) and sprayed with an optimized proline concentration 2.5 mM. The experiment consisted of a factorial arrangement of treatments in a completely randomized design. The results showed that there were maximum increases in shoot length (32.7%), root length (58.9%), and shoot fresh (85.7%). The quantities of leaves per plant were increased by 52.9%, 123.6%, 82.5%, and 62.2% in C1, C2, C3, and C4 after proline application. On the other hand, only root fresh weight decreased in all genotypes after proline application by 23.1%, 20%, 266.7%, and 280.8% (C1, C2, C3, C4). A lower leaf temperature of 27.72 °C, minimum transpiration of 3.29 mmol m−2 s−1, maximum photosynthesis of 3.91 μmol m−2 s−1, and a maximum water use efficiency of 1.20 μmol CO2 mmol H2O were recorded in the genotypes C2, C1, C3, and C4, respectively. The highest enzymatic activity of superoxide dismutase, peroxidase and catalase were 14.88, 0.31, and 0.15 U mg-protein in C2, C1, and C3, respectively. Maximum leaf proline, glycinebetaine, total free amino acids, and chlorophyll content 3.46 mg g−1, 4.02 mg g−1, 3.46 mg g−1, and 46.89 (in C2), respectively, due to foliar applications of proline. Another important finding was that heat tolerance in okra was highly linked highly linked to genotypes’ genetic potential, having more water use efficiency, enzymatic activities, and physio-biochemical attributes under the foliar applications of proline

Exploring Lead Zirconate Titanate, the Potential Advancement as an Anode for Li-Ion Batteries

Graphite, widely adopted as an anode for lithium-ion batteries (LIBs), faces challenges such as an unsustainable supply chain and sluggish rate capabilities. This emphasizes the urgent need to explore alternative anode materials for LIBs, aiming to resolve these challenges and drive the advancement of more efficient and sustainable battery technologies. The present research investigates the potential of lead zirconate titanate (PZT: PbZr0.53Ti0.47O3) as an anode material for LIBs. Bulk PZT materials were synthesized by using a solid-state reaction, and the electrochemical performance as an anode was examined. A high initial discharge capacity of approximately 686 mAh/g was attained, maintaining a stable capacity of around 161 mAh/g after 200 cycles with diffusion-controlled intercalation as the primary charge storage mechanism in a PZT anode. These findings suggest that PZT exhibits a promising electrochemical performance, positioning it as a potential alternative anode material for LIBs