This study investigated how salicylic acid (SA) mediates the response of melon (Cucumis melo) seeds to salt stress using physiological and transcriptomic methods. The effects of SA on the antioxidant enzymes, osmoregulatory substances, and transcriptome of melon seeds under salt stress were investigated using sodium chloride (NaCl, 100 mmol·L⁻¹) as the stress stimulant and SA + NaCl (0.25 mmol·L⁻¹ + 100 mmol·L⁻¹) as the alleviation treatment. The results showed that SA positively influences salt tolerance by increasing the activity of superoxide dismutase activity (SOD) and catalase activity (CAT) while decreasing proline content (Pro). Differentially expressed genes (DEGs) were identified by transcriptome data analysis, of which 2958 were up-regulated, and 2157 were down-regulated. These genes were mainly involved in the mitogen-activated protein kinase (MAPK) signaling pathway and plant hormone signal transduction, lipid metabolism (linoleic and α-linolenic fatty acid metabolism), biosynthesis of secondary metabolites (phenylpropanoid pathway and flavonoid biosynthesis), and related pathways. Further analysis revealed that SA might alleviate salt stress by initiating a series of signaling pathways under salt stress, participating in lignin biosynthesis to improve cell wall stability, and positively regulating lipoxygenase (LOX) genes. These results provide valuable information and new strategies for future salt resistance cultivation and high melon yield.

Tillage practices significantly influence crop yield and soil quality. This study investigated the impact of rotary tillage (RT) and deep tillage (DT) on soil properties, microbial diversity, and melon (Cucumis melo L.) root growth and yield. RT involved breaking up the topsoil to a depth of 15 cm using a rotary tiller, while DT employed a rotary tiller followed by a moldboard plow to turn the soil layer over to a depth of 35 cm. The melon variety “Nasimi” was used as the material. Our findings revealed a remarkable response of soil phosphorus to tillage practices. High-throughput sequencing results revealed a significant impact of tillage practices on the soil fungal composition, richness, and diversity but little impact on the bacterial communities. Compared to RT, DT markedly enhanced melon root length, root surface area, root volume, and mean root diameter by 47.42%, 56.70%, 58.83%, and 27.28%, respectively. Additionally, DT treatments significantly increased melon yield (53.46%) compared to RT. The results indicate that DT improves soil nutrient availability, affects soil fungal community characteristics, and optimizes root distribution in soil, thereby improving melon yield. The findings offer valuable theoretical insights for the implementation of effective tillage practices in open-field melon cultivation.

Background: The short strand-related sequence (SRS) gene family is a class of plant-specific transcription factors related to a group of genes known as the short internode (SHI) or SRS/STY gene family, which plays important roles in regulating plant growth and development and stress responses. Although the SRS genes have been studied in many plants, in cucurbit crops, they have thus far only been identified in cucumber. Methods: In the Cucurbitaceae database from melon (Cucumis melo), cucumber (Cucumis sativus), watermelon (Citrullus lanatus), bottle gourd (Lagenaria siceraria), wax gourd (Benincasa hispida), moschata pumpkin (Cucurbita moschata), and pumpkin (Cucurbita maxima), a total of 60 SRS genes were identified in seven Cucurbitaceae crops, which were classified into three subfamilies. Results: The same subfamily showed conserved motifs and gene structures. The differences in the number of SRS genes in different Cucurbitaceae crops implied likely gene loss or duplication events during evolution. Analysis of promoter cis-regulatory elements indicated that these SRS genes may be involved in hormone response, growth and development, and biotic and abiotic stress responses in plants. Most of the CmSRS genes in melons were expressed in the roots, with a few expressed in the leaves and ovaries. In addition, CmSRS expression was induced by biotic (wilt and powdery mildew) and abiotic (drought and salt) stresses. Subcellular localization of CmSRS proteins showed predominant expression in the nucleus. Conclusions: A total of 60 Cucurbitaceae SRS genes are present in the genomes of seven Cucurbitaceae crops. These cucurbit SRS genes seem to have maintained similar characteristics and functions during the evolutionary process. These results lay the foundation for the study of biological functions of SRS genes in Cucurbitaceae crops.

To elucidate the genetic factors contributing to melon resistance against Phelipanche aegyptiaca and comprehend the role of differentially resistant materials in responding to changes in P. aegyptiaca parasitisation, we investigated the P. aeg...