Overexpression of CsCaM3 Improves High Temperature Tolerance in Cucumber

Heat stress during cucumber production often leads to sunburn of leaves, growth retardation of stems and roots, fruit malformation, and even plant death, which have a great impact on the fruit quality and yield. However, no studies on the genetic inheritance and quantitative trait locus mapping of heat tolerance in cucumber at the adult stage have been reported yet. In this study, a set of 86 recombinant inbred lines (RILs) derived from “99281” (heat-tolerant) and “931” (heat-sensitive) were used to identify the heat tolerance QTL in summer 2018, 2019, and 2020. Eight-week-old plants were exposed to a natural high temperature environment in the field, and the heat injury index was used to indicate the heat tolerance performance. Genetic analysis showed that the heat tolerance of adult cucumber is quantitatively inherited. One QTL named qHT1.1 on chromosome 1 was identified. It was delimited by Indel 3-3 and Indel 1-15 and explained 59.6%, 58.1%, and 40.1% of the phenotypic variation in 2018, 2019, and 2020, respectively. The efficiency of marker HT-1, which is closely linked to the locus, was tested using 62 cucumber germplasm accessions and was found to have an accuracy of 97.8% in heat sensitive plants. The qHT1.1 was delimited to a 694.5-kb region, containing 98 genes, nine of which may be involved in heat tolerance. Further sequence analysis showed that there are three single-base substitutions within the coding sequences of Csa1G004990. Gene expression analyses suggested that the expression of Csa1G004990 was significantly higher in “99281” than “931” at 14d, 35d, 42d, and 49d after transplanting. This study provides practically useful markers for heat tolerance breeding in cucumber and provides a basis for further identifying heat tolerant genes.

Section: Introductionmentioning

confidence: 99%

QTL Mapping of Heat Tolerance in Cucumber (Cucumis sativus L.) at Adult Stage

Liu

Dong

Wei

et al. 2021

“…According to our data, a homologous VaCML44 gene shared 66% protein similarity to ShCML44 and was up-regulated under cold and salinity stress treatments (Figure 2). Overexpression of the CsCaM3 gene, which shared 100% protein similarity with VaCaM8 and VaCaM10, improved heat stress tolerance in cucumber [19]. Heat stress significantly increased transcript levels of the VaCaM8 and VaCaM10 genes after 6 h of treatment in our experiments (Figure 1).…”

Section: Discussionmentioning

confidence: 55%

“…Recently, a number of studies demonstrated that overexpression of plant CaM and CML genes can improve plant resistance to abiotic stresses [17][18][19][20]. For example, overexpression of the ShCML44 gene isolated from cold tolerant wild tomato enhanced the tolerance of a stress-sensitive tomato to cold, drought, and salinity [18].…”

Section: Discussionmentioning

confidence: 99%

The Effect of Abiotic Stress Conditions on Expression of Calmodulin (CaM) and Calmodulin-Like (CML) Genes in Wild-Growing Grapevine Vitis amurensis

Dubrovina

Aleynova

Ogneva

et al. 2019

Plant calmodulins (CaMs) and calmodulin-like proteins (CMLs) are important plant Ca2+-binding proteins that sense and decode changes in the intracellular Ca2+ concentration arising in response to environmental stimuli. Protein Ca2+ sensors are presented by complex gene families in plants and perform diverse biological functions. In this study, we cloned, sequenced, and characterized three CaM and 54 CML mRNA transcripts of Vitis amurensis Rupr., a wild-growing grapevine with a remarkable stress tolerance. Using real-time quantitative RT-PCR, we analyzed transcript abundance of the identified VaCaMs and VaCMLs in response to water deficit, high salinity, high mannitol, cold and heat stresses. Expression of VaCaMs and 32 VaCMLs actively responded to the abiotic stresses and exhibited both positive and negative regulation patterns. Other VaCML members showed slight transcriptional regulation, remained essentially unresponsive or responded only after one time interval of the treatments. The substantial alterations in the VaCaM and VaCML transcript levels revealed their involvement in the adaptation of wild-growing grapevine to environmental stresses.

“…Besides, Csa3G824920 and Csa3G824940 that encode NBS-containing resistance-like proteins, and Csa3G825010 that encodes Calmodulin-like protein 1, were also found within this region. A previous study suggested that overexpressing CsCaM3 , a Calmodulin gene, could prevent peroxidation and photosynthesis system damage, and thus improve heat tolerance [ 16 ]. Two transcription factors including Csa3G824990 and Csa3G822440 that encodes an NAC domain protein and an AP2-like ethylene-responsive transcription factor were also found in the major QTL.…”

Section: Discussionmentioning

confidence: 99%

“…The expression patterns of Hsfs in cucumber were studied and most of them were up-regulated under heat stress, indicating those involved in heat stress tolerance [ 14 ]. There are also studies showed that auxin synthesis genes CsYUC8 and CsYUC9 were significantly up-regulated in heat-tolerance materials [ 15 ], and overexpressing CsCaM3 , a Calmodulin gene, could prevent peroxidation and photosynthesis system damage, and thus improve heat tolerance [ 16 ].…”

Section: Introductionmentioning

confidence: 99%

Identification of Quantitative Trait Loci Controlling High-Temperature Tolerance in Cucumber (Cucumis sativus L.) Seedlings

Dong

Zhang

Wei

et al. 2020

High temperature is one of the major abiotic stresses that affect cucumber growth and development. Heat stress often leads to metabolic malfunction, dehydration, wilting and death, which has a great impact on the yield and fruit quality. In this study, genetic analysis and quantitative trait loci (QTL) mapping for thermotolerance in cucumber seedlings was investigated using a recombinant inbred line (RILs; HR) population and a doubled haploid (DH; HP) population derived from two parental lines ‘65G’ (heat-sensitive) and ‘02245′ (heat-tolerant). Inheritance analysis suggested that both short-term extreme and long-term mild thermotolerance in cucumber seedlings were determined by multiple genes. Six QTLs for heat tolerance including qHT3.1, qHT3.2, qHT3.3, qHT4.1, qHT4.2, and qHT6.1 were detected. Among them, the major QTL, qHT3.2, was repeatedly detected for three times in HR and HP at different environments, explained 28.3% of the phenotypic variability. The 481.2 kb region harbored 79 genes, nine of which might involve in heat stress response. This study provides a basis for further identifying thermotolerant genes and helps understanding the molecular mechanism underlying thermotolerance in cucumber seedlings.