Response of Tomato (Solanum lycopersicum L.) Genotypes to Heat Stress Using Morphological and Expression Study

Characterization and Early Response of the DEAD Gene Family to Heat Stress in Tomato

The DEAD-box RNA helicase family, acting as a critical regulator in RNA metabolism, plays a vital role in plant growth, development, and adaptation to various stresses. Although a number of DEAD proteins have been reported to participate in heat stress response in several species, the response of DEAD-box RNA helicases to heat stress has not been comprehensively analyzed in tomato. In this study, 42 SlDEAD genes were identified from the tomato genome. Evolutionary analysis of DEAD family genes across different plant species reveals that DEAD family genes can be segregated into five groups. A comprehensive analysis of their physicochemical properties, gene structure, chromosome location, and conserved motifs unveils diversity among the members of the SlDEAD family. An investigation into the subcellular localization of seven SlDEAD proteins indicates that SlDEAD7, SlDEAD14, and SlDEAD26 are located in the endoplasmic reticulum, and SlDEAD40 is located in the endoplasmic reticulum and nucleus, whereas SlDEAD17, SlDEAD25, and SlDEAD35 are located in the chloroplast. The expression of 37 out of 42 SlDEAD genes was responsive to heat stress induction. During the early stage of high-temperature treatment, they exhibited five distinct expression patterns. These findings contribute to a deeper comprehension of the evolution, expansion complexity, and function of SlDEAD genes and provide insights into the potential role of SlDEAD genes in tomato tolerance to heat stress.

Protective mechanisms of exogenous melatonin on chlorophyll metabolism and photosynthesis in tomato seedlings under heat stress

Elevated temperatures severely affect plant growth, reducing yield and quality. Melatonin (MT), a plant biomolecule, is known to enhance stress tolerance, but its role in heat resistance and underlying mechanisms require further exploration. This study investigates MT's regulatory effects on chlorophyll metabolism and photosynthesis in tomato seedlings under high-temperature stress (40°C). Tomato seedlings treated with 100 μmol MT showed improved physiological and photosynthetic performance under heat stress. MT application increased osmolytes (proline and soluble sugar), enhanced antioxidant enzyme activities [catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX)], and reduced oxidative damage markers (H2O2, O2 -, malondialdehyde, and conductivity). Photosynthetic parameters, including key enzyme activities [sedoheptulose-1,7-bisphosphatase (SBPase), ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), and NADP-dependent glyceraldehyde-3-phosphate dehydrogenase (NADP-GAPDH)], photochemical efficiency [Fv/Fm and Y(II)], and photochemical quenching (Qp), were significantly improved, restoring the OJIP curve and enhancing photosynthesis. MT also regulated chlorophyll metabolism by promoting synthesis [increasing chlorophyll a and b, 5-aminolevulinic acid (ALA), Mg-protoporphyrin (Mg Proto), and protochlorophyllide (Pchlide) levels] and upregulating synthesis genes (SlHEMA1, SlPORB, SlPORC, and SlCHLI) while inhibiting degradation genes (SlCLH1, SlCLH2, SlPAO, SlPPH, and SlRCCR). These findings demonstrate that MT enhances tomato heat tolerance by protecting chlorophyll metabolism and photosynthesis, offering a theoretical basis for improving crop resilience to heat stress.

Evaluation of high temperature impacts and nanotechnology as a shield against temperature stress on tomatoes - A review

Rising temperature due to changing climate significantly impacts the production of tomato. The morpho-physiological functions of tomato such as gas exchange, growth and development, flowering, fruit setting, quality, fruit size, weight that can influence the yield and production is drastically affected by higher temperatures. Among the growth stages of tomato, flowering and fruit setting stage is highly vulnerable to high temperature resulting in reduced flower numbers, increased flower abortion, stigma exertion, abnormal ovule, reduced pollen germination, pollen numbers, pollen tube development, pollen viability and increased male sterility. The flower to fruit ratio and duration also highly influenced by higher temperatures. It significantly reduced fruit set, fruit number, weight and quality (Lycopene, carotenoids), changing sugars and acids ratio. Apart from day temperature, the asymmetrically rising night temperature and difference in day and night temperature pattern plays a considerable role in physiological and biochemical processes of tomato. Nanotechnology proves to be a successful tool for sustainable production of tomato than many other alternative mitigation strategies due to its localized action, low quantity requirement, minimal wastage, less residues, eco friendliness, biodegradability, multifunctionality, synergistic capabilities and higher plant productivity. It imitates the antioxidant enzymes playing active role in physiological functions in tomato thereby inducing tolerance mechanisms for managing high temperature stress. Further research should focus on use of several other nanoparticles that have potential but not yet experimented on tomato to mitigate heat stress and producing biodegradable, green synthesized nanoparticles that are cost effective and affordable to farmers.

Data set for estimating combining abilities for yield and quality attributes in summer tomato using line by tester analysis in Bangladesh

This article provides a dataset for line × tester analysis in the F1 generation of summer tomatoes using open-source R statistical software and the 'agricolae' package. The dataset includes seven inbred lines as female parents (L) and two testers as male parents (T) with diverse genetic bases and heat tolerance qualities. Fourteen cross combinations were produced through L × T (7 × 2) mating design, involving hybridization between lines (f) and testers (m) in a one-to-one fashion. To assess the heterosis of the crosses, all parents (both lines and testers) were included along with the crosses and evaluated in the same experimental field for 16 traits using a randomized complete block design (RCBD) with two replications. The line × tester analysis estimates the ANOVA, including parents, combining ability, genetic components, and the contribution of parental lines to genetic variation in the hybrids. This dataset is valuable for breeders in subtropical countries to develop efficient breeding strategies for hybrid summer tomato varieties.

A dataset on multi-trait selection approach for the evaluation of F1 tomato hybrids along with their parents under hot and humid conditions in Bangladesh

This dataset aims to evaluate the use of multiple trait-based selection methods with multi-trait genotype-ideotype distance index (MGIDI) models to identify superior summer F1 tomato hybrids suitable for the climatic conditions of countries like Bangladesh. The dataset was generated using 14 cross combinations from a Line × Tester mating design, along with seven parental lines and two tester parents of tomatoes with diverse genetic bases and heat tolerance qualities in a randomized complete block (RCB) design. The likelihood ratio (LR) test indicated highly significant genotype effects for most of the analyzed traits. A heatmap of correlation analyses between 16 traits identified a highly significant positive correlation (r > 0.8) between NFrPC and NFPC and between AFW and FW, preliminarily indicating a clear trace of multicollinearity among these traits. The traits NFPP, YPP, and Yield showed the highest predicted genetic gains, indicating their potential for substantial improvement through selection. Additionally, the heritability estimates ranged from 0.54 to 0.99, highlighting high heritability across the traits, which suggests favourable conditions for effective selection strategies. The strengths and weaknesses of hybrids AVTOV1002×C41 and AVTOV1010×C41 were evaluated based on their contributions to MGIDI across four major factors. These hybrids demonstrated strong performance, particularly excelling in traits associated with FA1, FA2, and FA4. The dataset of MGIDI can be universally applied to rank treatments based on desired values of multiple traits, with its potential for rapid expansion in evaluating various types of plant experiments.

Deleterious Effects of Heat Stress on the Tomato, Its Innate Responses, and Potential Preventive Strategies in the Realm of Emerging Technologies

The tomato is a fruit vegetable rich in nutritional and medicinal value grown in greenhouses and fields worldwide. It is severely sensitive to heat stress, which frequently occurs with rising global warming. Predictions indicate a 0.2 °C increase in average surface temperatures per decade for the next three decades, which underlines the threat of austere heat stress in the future. Previous studies have reported that heat stress adversely affects tomato growth, limits nutrient availability, hammers photosynthesis, disrupts reproduction, denatures proteins, upsets signaling pathways, and damages cell membranes. The overproduction of reactive oxygen species in response to heat stress is toxic to tomato plants. The negative consequences of heat stress on the tomato have been the focus of much investigation, resulting in the emergence of several therapeutic interventions. However, a considerable distance remains to be covered to develop tomato varieties that are tolerant to current heat stress and durable in the perspective of increasing global warming. This current review provides a critical analysis of the heat stress consequences on the tomato in the context of global warming, its innate response to heat stress, and the elucidation of domains characterized by a scarcity of knowledge, along with potential avenues for enhancing sustainable tolerance against heat stress through the involvement of diverse advanced technologies. The particular mechanism underlying thermotolerance remains indeterminate and requires further elucidatory investigation. The precise roles and interplay of signaling pathways in response to heat stress remain unresolved. The etiology of tomato plants' physiological and molecular responses against heat stress remains unexplained. Utilizing modern functional genomics techniques, including transcriptomics, proteomics, and metabolomics, can assist in identifying potential candidate proteins, metabolites, genes, gene networks, and signaling pathways contributing to tomato stress tolerance. Improving tomato tolerance against heat stress urges a comprehensive and combined strategy including modern techniques, the latest apparatuses, speedy breeding, physiology, and molecular markers to regulate their physiological, molecular, and biochemical reactions.

Study on peanut protein oxidation and metabolomics/proteomics analysis of peanut response under hypoxic/re-aeration storage

To better understand the effect of oxygen levels in the storage environment on peanut protein oxidation and explore the mechanism, the functional properties and the oxidation degree of peanut proteins extracted from peanuts under conventional storage (CS), nitrogen modified atmosphere storage (NS, hypoxic) and re-aeration storage (RS) were investigated. Metabolomics and proteomics were employed to analyze peanut's response to hypoxic/re-aeration storage environment. The results showed that NS retarded the decline of the functional properties and the oxidation of peanut proteins, while the process were accelerated after re-aeration. That was the result of the metabolic changes of peanuts under different storage environments. The omics results presented the decreased (NS)/increased (RS) levels of the antioxidant-related proteins acetaldehyde dehydrogenase and glutathione S-transferase, and the inhibition (NS)/activation (RS) of metabolic pathways such as the TCA cycle and the pentose phosphate pathway. This study provided a reference for the re-aeration storage of other agricultural products.

Morphological and physio-biochemical responses under heat stress in cotton: Overview

Cotton is an important cash crop in addition to being a fiber commodity, and it plays an essential part in the economies of numerous nations. High temperature is the most critical element affecting its yield from fertilization to harvest. The optimal temperature for root formation is 30 C -35 °C; however, root development ends around 40 °C. Increased temperature, in particular, influences different biochemical and physiological processes associated with cotton plant, resulting in low seed cotton production. Many studies in various agroecological zones used various agronomic strategies and contemporary breeding techniques to reduce heat stress and improve cotton productivity. To attain desired traits, cotton breeders should investigate all potential possibilities, such as generating superior cultivars by traditional breeding, employing molecular techniques and transgenic methods, such as using genome editing techniques. The main objective of this review is to provide the recent information on the environmental factors, such as temperature, heat and drought, influence the growth and development, morphology and physio-chemical alteration associated with cotton. Furthermore, recent advancement in cotton breeding to combat the serious threat of drought and heat stress.

Genomic Insights into the Origin of a Thermotolerant Tomato Line and Identification of Candidate Genes for Heat Stress

Climate change represents the main problem for agricultural crops, and the constitution of heat-tolerant genotypes is an important breeder’s strategy to reduce yield losses. The aim of the present study was to investigate the whole genome of a heat-tolerant tomato genotype (E42), in order to identify candidate genes involved in its response to high temperature. E42 presented a high variability for chromosomes 1, 4, 7 and 12, and phylogenetic analysis highlighted its relationship with the wild S. pimpinellifolium species. Variants with high (18) and moderate (139) impact on protein function were retrieved from two lists of genes related to heat tolerance and reproduction. This analysis permitted us to prioritize a subset of 35 candidate gene mapping in polymorphic regions, some colocalizing in QTLs controlling flowering in tomato. Among these genes, we identified 23 HSPs, one HSF, six involved in flowering and five in pollen activity. Interestingly, one gene coded for a flowering locus T1 and mapping on chromosome 11 resides in a QTL region controlling flowering and also showed 100% identity with an S. pimpinellifolium allele. This study provides useful information on both the E42 genetic background and heat stress response, and further studies will be conducted to validate these genes.

Response of Cnidium officinale Makino Plants to Heat Stress and Selection of Superior Clones Using Morphological and Molecular Analysis

Cnidium officinale is a medicinal plant cultivated for its rhizomes, which are used in Chinese, Japanese, and Korean traditional medicine. This medicinal crop is highly susceptible to heat stress and cannot be cultivated in regions of higher temperatures. In the present study, ten clones from Korea (clones 1, 2, 5, 6, 8, 11, 14, 15, 22, and 26) were evaluated for their heat tolerance in vitro at 25, 30, 32.5, and 35 °C, and growth characteristics including plant height, the number of leaves and roots were evaluated. The initial experiment was conducted to find the threshold level for significant damage to the plant, while the second experiment was to screen the germplasm to select heat-tolerant clones. Most of the clones were sensitive to heat stress (clones 1, 2, 8, 11, 14, 15, 22, and 26), and few clones (clones 5 and 6) could perform well at an elevated temperature of 32.5 °C. Molecular analysis of the expression of heat-responsive genes, including heat shock protein (CoHSP), catalase (CoCAT), and cystine protease (CoCP), was performed by quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) carried out with heat-tolerant and heat-sensitive clones. Two of the heat-tolerant clones (clones 5 and 6) showed significant expression of CoHSP and CoCAT genes at elevated temperature treatment. These clones can be used for further evaluation and cultivation.