Journal of Integrative Agriculture最新文献

Spermatogonial stem cells (SSCs) are the key to maintaining production of the sperms and healthy offsprings, and also treating breeding livestock's reproductive damage and infertility. MicroRNAs act a decisive role in regulating gene expression in many cells and tissues, including in processes such as proliferation, self-renewal, differentiation, and apoptosis of stem cells. However, the miRNA mechanism in regulation of SSCs is still unclear. Here, high-throughput sequencing was used to identify specific miRNAs. We confirmed that miR-21-5p was concentrated in both goat and mouse SSCs, and enhanced the proliferation and antiapoptotic ability of SSCs. In vivo experiments have shown that miR-21-5p resisted the damage of the chemotherapy drug Busulfan to germ cells, ameliorated Busulfan-induced testicular dysfunction, and maintained spermatogenesis. Further RNA-seq and target gene prediction revealed that SPRY1 and FASLG are targets of miR-21-5p, thereby activating downstream signaling pathways such as MAPK/ERK, PI3K-AKT, and apoptosis. In summary, miR-21-5p is crucial for the self-renewal and maintenance of SSCs. This study provides new avenues for treating breeding livestock's reproductive damages, infertility, oligospermia, and other conditions.

The practice of intercropping leguminous and gramine for promoting sustainable agriculture, optimizing resource utilization, enhancing biodiversity, and reducing reliance on petroleum products. However, promoting conventional intercropping strategies in modern agriculture can prove challenging. The innovative technology of soybean maize strip intercropping (SMSI) has been proposed as a solution. It has produced remarkable results in improving domestic soybean and maize production for both food security and sustainable agriculture. In this article, we will provide an overview of SMSI and explain how it differs from traditional intercropping. We will also discuss the core principles that foster higher yields and the prospects for its future development.¹

The improvement of soybean seed carotenoid contents is indispensably important owing to its beneficial role to human health and nutrition. However, the genetic architecture underlying soybean carotenoid biosynthesis remains largely unknown. In the present study, we employed the next generation sequencing-based bulked-segregant analysis for identifying new genomic regions governing seed carotenoids in 1551 natural soybean accessions. The genomic DNA samples of individual plants with extreme phenotype were pooled to form two bulks with high (50 accessions) and low (50 accessions) carotenoid contents for Illumina sequencing. A total of 125.09 Gbp of clean bases and 89.82% of Q30 were obtained and the average alignment efficiency was 99.45% with average coverage depth of 62.20× and 99.75% genome coverage. Based on the G’ method analysis, a total of 16 candidate genomic loci with a total length 20.41 Mb were found to be related to the trait. Of these loci, the most significant region displaying the highest elevated G’-value was found in chromosome 06 at a position of 18.53-22.67 Mb, and chromosome 19 at a genomic region intervals of 8.36-10.94, 12.06-13.79 and 18.45-20.26 Mbs, and were preferably taken to identify the key candidate genes. In these regions, 250 predicted genes were found and analyzed to get 90 significantly enriched (P<0.05) gene ontology (GO)-terms. Based on ANNOVAR analysis, 50 genes with non-synonymous and stopgained mutations were preferentially selected as potential candidate genes. Of which, following their gene annotation function and high significant haplotype variation in various environments, five genes were identified as the most promising candidate genes regulating soybean seed carotenoid accumulation, and suggested for further functional validation studies. Collectively, understanding the genetic bases of carotenoid pigments and identifying genes underpinning carotenoid accumulation via bulked-segregant analysis sequencing (BSA-seq) approach provide new insight for exploring future molecular breeding of high carotenoid content in soybean cultivars.

A few Trichoderma species have been utilized as biocontrol agents in agriculture due to their ability to inhibit growth of phytopathogens. However, the antagonistic mechanism of some strains is mainly performed by direct action. The objective of our study is to explore an effective strain that has comprehensive abilities, and preliminarily clarify its practical viability and action mechanism. Trichoderma gamsii strain TC959 possessing abilities of strong antagonism and plant growth promotion was singled out. It released secondary metabolites, siderophores and chitinase/xylanase to directly inhibit the growth of plant pathogens, or released indole-3-acetic acid/gibberellin to promote plant growth. The strain also activated induced systemic resistance by increasing chlorophyll a/b ratio and jasmonic acid content of pepper seedlings through root colonization, which resulted in the improvements of defense-related gene expression levels, antioxidant enzyme activity, and indole-3-acetic acid/gibberellin production. Thereby disease resistance and plant growth were enhanced and promoted, respectively. Furthermore, TC959 had a resistance advantage to oxidation and chemical fungicides, which helped viability of the strain to be maintained, and healthy pepper seedlings were effectively ensured. In conclusion, strain TC959 has biocontrol potential and comprehensive functions against pepper damping-off disease, which is valuable for further practical applications.

Activity of bc₁ complex kinase (ABC1K) is an atypical protein kinase (aPK) that plays a crucial role in plant mitochondrial or plastid stress responses, but little is known about the responses of ABC1Ks to stress in cotton (Gossypium spp.). Here, we verified 40 ABC1Ks in upland cotton (Gossypium hirsutum L.) and found that GhABC1Ks were unevenly distributed across 17 chromosomes. GhABC1K family members contained 35 paralogous gene pairs and were expanded by segmental duplication. The GhABC1K promoter sequences contained diversified cis-acting regulatory elements relevant to hormone or stress responses. The qRT–PCR results revealed that most GhABC1Ks were upregulated by exposure to different stresses. GhABC1K2-A05 and GhABC1K12-A07 expression was upregulated by at least three stress treatments. These genes were further functionally characterized by virus-induced gene silencing (VIGS). Compared with the controls, the GhABC1K2-A05- and GhABC1K12-A07-silenced cotton lines exhibited a higher malondialdehyde (MDA) content, lower catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) activities and reduced chlorophyll and soluble sugar contents under NaCl and PEG stress. In addition, the expression of stress marker genes (GhDREB2A, GhSOS1, GhCIPK6, GhSOS2, GhWRKY33, and GhRD29A) was significantly downregulated after stress in the GhABC1K2-A05- and GhABC1K12-A07-silenced lines. The results indicate that knockdown of GhABC1K2-A05 and GhABC1K12-A07 make cotton more sensitive to salt and PEG stress. These findings can provide valuable information for intensive studies of GhABC1Ks in the responses and resistance of cotton to abiotic stresses.

Salinity is a major environmental stress affecting crop growth and productivity globally. The application of halo-tolerant plant growth-promoting bacteria (HT-PGPB) has been widely recognized to promote crop growth and reduce the adverse effects of salt stress. Herein, key endophytic bacteria that can respond to salinity changes were identified by analysis of the microbial community in propagules of Kandelia obovate. Delftia tsuruhatensis DYX29, a strain able to grow normally under high salinity conditions with a sodium chloride (NaCl) concentration of 5% (w/v), was obtained by pure culture. DYX29 has the ability to produce siderophores with a siderophore unit value of 87.6% and ACC (1-aminocyclopropane-1-carboxylate) deaminase with 29 U L^-1 and can synthesize intracellular amino acids and auxin induced by high salinity. Inoculation with DYX29 can remarkably promote the salt tolerance of rice. Under salt stress, the addition of DYX29 effectively promoted the growth of rice seedlings through a variety of approaches. It increased the biomass of rice seedlings by 32.9% (dry weight) and promoted the accumulation of soluble sugars by 23.1%. It also increased CAT and POD activities in rice leaves by 37.8 and 88.2%, respectively. Moreover, it maintained ionic homeostasis in roots and leaves. In addition, it upregulated the expression of growth-promoting hormones in roots, such as IAA, BL, ABA and SA, in rice roots by 27.8, 69.5, 123.7 and 28.6%, respectively. This study provides inspiration for screening valuable salt-tolerant pro-biotic bacteria from mangrove ecosystems for crop growth promotion under salt stress. It may also provide useful references for the development of new salt-tolerant and pro-biotic biofertilizers and the investigation of the related mechanism.

Skeletal muscle satellite cells are stem cells that are known for their multipotency and ability to proliferate in vitro. However, primary skeletal muscle satellite cells have limited proliferative capacity in vitro, which hinders their study in poultry skeletal muscle. The emergence of immortalization techniques for cells has provided a useful tool to overcome this limitation and explore the functions of skeletal muscle satellite cells. In this study, we achieved the immortalization of chicken skeletal muscle satellite cells by transducing primary cells with TERT (Telomerase reverse transcriptase) amplified from chicken (chTERT) using a lentiviral vector through reconstitution of telomerase activity. The cells successfully bypassed replicative senescence but did not achieve true immortalization. Preliminary functional characterization of the established cell line revealed that the proliferative characteristics and cell cycle profile of the immortalized chicken skeletal muscle satellite cell lines (ICMS) were similar to those of chicken primary muscle satellite cells (CPMSCs). Serum dependency analysis and soft agar assays indicated that ICMS did not undergo malignant transformation. Induced differentiation results demonstrated that ICMS retained their capacity for differentiation. The cell lines established in this study provide an important basis for the establishment of immortalized poultry cell lines and a cell model for the study of poultry skeletal muscle-related functional genes.

Cattle carcass traits are economically important in the beef industry. In the present study, we identified 184 significant genes and 822 alternative genes for 7 carcass traits using genome-wide association studies (GWASs) in 1566 Huaxi beef cattle. We then identified 5,860 unique cis-genes and 734 trans-genes in 227 longissimus dorsi muscle (LDM) samples to better understand the genetic regulation of gene expression. Our integration study of the GWAS and cis-eQTL analysis detected 13 variants regulating 12 identical genes, in which one variant was also detected in fine-mapping analysis. Moreover, using a transcriptome-wide association study (TWAS), we identified 4 genes (TTC30B, HMGA1, PRKD3 and FXN) that were significantly related to carcass chest depth (CCD), carcass length (CL), carcass weight (CW) and dressing percentage (DP). This study identified variants and genes that may be useful for understanding the molecular mechanism of carcass traits in beef cattle.

Yaks are well-adapted to the harsh environment of the Tibetan plateau, and they emit less enteric methane (CH₄) and digest poor-quality forage better than cattle. To examine the potential of yak rumen inoculum to mitigate CH₄ production and improve digestibility in cattle, we incubated substrate with rumen inoculum from yak (YRI) and cattle (CRI) in vitro in five ratios (YRI: CRI): 0:100 (control), (2) 25:75, (3) 50:50, (4) 75:25 and (5) 100:0 for 72 h. The YRI: CRI ratios of 50:50, 75:25 and 100:0 produced less total gas and CH₄ and accumulated less hydrogen (H₂) than 0: 100 (control) at most time points. From 12 h onwards, there was a linear decrease (P < 0.05) in carbon dioxide (CO₂) production with increasing YRI: CRI ratio. At 72 h, the ratios of 50:50 and 75:25 had higher dry matter (+7.71% and +4.11%, respectively), as well as higher acid detergent fiber digestibility (+15.5% and +7.61%, respectively), when compared to the 0:100 ratio (P < 0.05). Increasing the proportion of YRI generally increased total VFA concentrations, and, concomitantly, decreased the proportion of metabolic hydrogen ([2H]) incorporated into CH₄, and decreased the recovery of [2H]. The lower [2H] recovery indicates unknown [2H] sinks in the culture. Estimated Gibbs free energy changes (∆G) for reductive acetogenesis were negative, indicating the thermodynamic feasibility of this process. It would be beneficial to identify: 1) the alternative [2H] sinks, which could help mitigate CH₄ emission, and 2) core microbes involved in fiber digestion. This experiment supported lower CH₄ emission and greater nutrient digestibility of yaks compared to cattle. Multi-omics combined with microbial culture technologies developed in recent years could help to better understand fermentation differences among species.

Late sowing is a critical factor that hinders achieving high-yield, good-quality wheat under rice-wheat rotation. Understanding the physiological basis and regulatory pathways that lead to late-sown wheat of high yield and good quality is crucial for developing effective cultivation strategies. A 2-year field experiment was conducted to investigate the effects of sowing date, nitrogen (N) application rate, and planting density on wheat yield, grain quality, population characteristics, and the underlying physiological factors. The results revealed significant interactions among the sowing date, planting density, and N application in regulating both yield and quality. Late sowing reduced grain yield primarily by reducing the number of spikes and kernels. However, the latter was improved by increasing N application and the planting density, thus mitigating the yield losses caused by late sowing. Moreover, the grain protein content (GPC) and wet gluten content (WGC) increased with delayed sowing dates and higher N rates, but decreased with increased planting densities. For wheat yields over 9,000 or 7,500 kg ha^–1, the latest sowing date should not be later than Nov. 4 or 15, respectively. In addition, specific criteria should be met, including a maximum of 1.5 and 1.0 million stems and tillers ha^–1, a maximum leaf area index of 6.7 and 5.5, and a dry matter accumulation (DMA) at anthesis of 14,000 and 12,000 kg ha^–1, respectively. For high-yield, good-quality late-sown wheat, the optimal combination is a 25% increase in the N rate (300 kg N ha^–1) and a planting density of 2.25 million (N300D225) or 3.75 million (N300D375) plants ha^–1 for 10- or 20-day delays in sowing, respectively. These combinations result in higher leaf net photosynthetic rate; higher activities of leaf nitrate reductase, glutamine synthetase, and grain glutamic pyruvic transaminase; and a lower sugar-N ratio during post-anthesis.