Gm Crops & Food-Biotechnology in Agriculture and the Food Chain最新文献

Genetically modified crop adoption in Canada has been the key driver in removing tillage as the lead form of weed control, due to increased weed control efficiency. Land use has transitioned from the use of summerfallow to continuous cropping, predominantly involving zero or minimum tillage practices. Prairie crop rotations have diversified away from mainly cereals to include three-year rotations of cereals, pulses, and oilseeds. Total herbicide volume applied has increased as crop production acres increased, but the rate of herbicide active ingredient applied per hectare has declined. Diverse crop rotations allow for weed control using herbicides with different modes of action, reducing selection pressure for resistant weed development. Herbicide-resistant weeds are an important concern for farmers, as the loss of key herbicides would make weed control exceedingly more difficult. The objective of this case study is to examine herbicide resistance weed development in the Canadian Prairies and to identify changes in resistance development following GM crop adoption.

The safety assessment of stacked transgenic crops is essential for their commercial cultivation. A crucial element of safety assessment is the nutritional evaluation of transgenic crops. Currently, profiling methods like transcriptome are employed as supplemental analytical tools to find the unintended effects of transgenic crops. In this study, stacked transgenic maize ZDRF8×nCX-1 was produced by crossing of two transgenic maize events ZDRF8 and nCX-1. This stacked transgenic maize expresses five genes: cry1Ab, cry2Ab and g10evo-epsps (from ZDRF8), as well as cp4 epsps and P450-N-Z1 (from nCX-1). Molecular analysis showed that the insertion sites of target genes were not changed during stack breeding, and the target genes are effectively expressed at both RNA and protein levels in ZDRF8×nCX-1. Target trait analysis showed that ZDRF8×nCX-1 exhibits tolerant to glyphosate, flazasulfuron and MCPA, and is resistant to damage by corn borers. Transcriptome analysis revealed that gene-stacked maize ZDRF8×nCX-1 did not significantly alter transcriptome profiles compared to the transgenic maize events ZDRF8 and nCX-1. Nutritional composition analysis showed that the grain profile of ZDRF8×nCX-1 was substantially equivalent to that of the non-transgenic counterpart. These results suggest that hybrid stacking does not cause significantly unintended effects beyond providing the intended beneficial traits.

Potato (Solanum tuberosum L.) is an important global crop, but its production is severely impacted by late blight, caused by the pathogen Phytophthora infestans. The economic burden of this disease is significant, and current control strategies rely mainly on fungicides, which face increasing regulatory and environmental constraints. To address this challenge, potatoes with resistance genes from wild potato relatives offer a promising solution. This study evaluated field resistance to late blight in potato lines (Maris Piper) containing the Solanum americanum resistance genes Rpi-amr3 and Rpi-amr1 across three years (2018-2020) in Sweden. Field trials were conducted under natural infection conditions to assess disease resistance. Results showed that the transgenic lines conferred strong resistance to late blight compared to the susceptible control. However, slight late blight symptoms were observed in the transgenic lines. These results highlight the effectiveness of S. americanum resistance genes in providing strong resistance, and emphasize the potential of stacking multiple R genes, including these genes to maintain efficacy. This research supports the development of resistant potato varieties as a sustainable alternative to chemical control, promoting food security and environmentally friendly agriculture.

Agriculture is essential to South Africa's economy, and maize is a crucial crop for smallholder farmers in the Eastern Cape. Traditional maize varieties face challenges related to productivity and resilience, prompting the promotion of Improved Maize Varieties (IMVs) to enhance yields and efficiency. This study investigates the impact of IMV adoption on agricultural productivity and technical efficiency in the region, addressing a gap in empirical evidence. Using a multistage random sampling approach, data was collected from 150 smallholder maize farmers and analyzed using stochastic production frontier, endogenous switching regression models, and the stochastic meta-frontier model. The study results reveal that 62% of the farmers are male, averaging 53 years old, and manage about four hectares with a mean monthly income of ZAR 3,562.13. Challenges, such as rainfall shortages and limited access to credit, hinder IMV adoption, although high access to extension services and diverse input use positively affect productivity. The adopted IMVs by farmers, including open-pollinated, hybrid, and genetically modified (GM) varieties, significantly boost maize yields and farm returns - yielding an average increase of 1.92 kg/ha and returns of ZAR 468.01 per hectare. Key adoption factors are education, farm size, and access to seeds and extension services, whereas barriers include market distance and family size. Technical efficiency is generally high at 74%, with farm size, seed, pesticides, agrochemicals, and fertilizers positively impacting maize production, whereas family labor negatively affects it. Factors such as age, education, and access to services significantly reduce technical inefficiency, while herd size, off-farm income, and distance to the market have mixed effects. The stochastic meta-frontier approach reveals that smallholder farmers adopting improved technologies show higher mean technical efficiency, indicating that advanced methods contribute to better resource use and productivity than traditional systems. This study suggests that targeted support is needed for farmers, enhancing access to extension services, affordable seeds, financial support, and investing in infrastructure and education can further improve adoption rates, technical efficiency, and overall productivity. Promoting improved technologies such as maize varieties will enhance the technical efficiency of farms, regardless of their adoption status. It would be key to improving overall agricultural productivity and farm household incomes.

Maize (Zea mays L.) is a major food and feed crop and an important raw material for energy, chemicals, and livestock. The NF-Y family of transcription factors in maize plays a crucial role in the regulation of plant development and response to environmental stress. In this study, we successfully cloned and characterized the maize NF-Y transcription factor gene ZmNF-YB10. We used bioinformatics, quantitative fluorescence PCR, and other techniques to analyze the basic properties of the gene, its tissue expression specificity, and its role in response to drought, salt, and other stresses. The results indicated that the gene was 1209 base pairs (bp) in length, with a coding sequence (CDS) region of 618 bp, encoding a polypeptide composed of 205 amino acid residues. This polypeptide has a theoretical isoelectric point of 5.85 and features a conserved structural domain unique to the NF-Y family. Quantitative fluorescence PCR results demonstrated that the ZmNF-YB10 gene was differentially upregulated under drought and salt stress treatments but exhibited a negatively regulated expression pattern under alkali and cold stress treatments. Transgenic Arabidopsis thaliana subjected to drought and salt stress in soil showed greener leaves than wild-type A. thaliana. In addition, the overexpression lines showed reduced levels of hydrogen peroxide (H₂O₂), superoxide (O^2-), and malondialdehyde (MDA) and increased activities of peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD). Western blot analysis revealed a distinct band at 21.8 kDa. Salt and drought tolerance analyses conducted in E. coli BL21 indicated a positive regulation. In yeast cells, ZmNF-YB10 exhibited a biological function that enhances salt and drought tolerance. Protein interactions were observed among the ZmNF-YB10, ZmNF-YC2, and ZmNF-YC4 genes. It is hypothesized that the ZmNF-YB10, ZmNF-YC2, and ZmNF-YC4 genes may play a role in the response to abiotic stresses, such as drought and salt tolerance, in maize.

Biological nitrogen fixation (BNF) is the most cost-effective and environmentally benign method for nitrogen fertilization. Isoflavones are important signaling factors for BNF in leguminous plants. Whether chalcone isomerase (CHI), the key enzyme gene in the flavonoid synthesis pathway, contributes to soybean (Glycine max) nodulation has not yet been fully clarified. In the present study, we identified the functions of three types of GmCHI for BNF using a hairy root system. The results showed that GmCHI1A and GmCHI1B1 positively increased nodulation while GmCHI1B2 did not, with the GmCHI1A gene having a greater effect than GmCHI1B1. Meanwhile, the daidzein and genistein contents were significantly increased in composite plants overexpressing GmCHI1A and reduced in composite plants, thus interfering with GmCHI1A. However, overexpression of GmCHI1B1 significantly increased the content of glycitein but not daidzein, genistein content implied that homologous genes exhibit functional differentiation. These results provide a reference for subsequent studies on improving nitrogen fixation in soybeans and providing functional genes for the improvement of new varieties.

Genome editing tools have rapidly been adopted by plant scientists for crop improvement. Genome editing using a multiplex sgRNA-CRISPR/Cas9 genome editing system is a useful technique for crop improvement in monocot species. In this study, we utilized precise gene editing techniques to generate wheat 3'(2'), 5'-bisphosphate nucleotidase (TaSal1) mutants using a multiplex sgRNA-CRISPR/Cas9 genome editing system. Five active TaSal1 homologous genes were found in the genome of Giza168 in addition to another apparently inactive gene on chromosome 4A. Three gRNAs were designed and used to target exons 4, 5 and 7 of the five wheat TaSal1 genes. Among the 120 Giza168 transgenic plants, 41 lines exhibited mutations and produced heritable TaSal1 mutations in the M₁ progeny and 5 lines were full 5 gene knock-outs. These mutant plants exhibit a rolled-leaf phenotype in young leaves and bended stems, but there were no significant changes in the internode length and width, leaf morphology, and stem shape. Anatomical and scanning electron microscope studies of the young leaves of mutated TaSal1 lines showed closed stomata, increased stomata width and increase in the size of the bulliform cells. Sal1 mutant seedlings germinated and grew better on media containing polyethylene glycol than wildtype seedlings. Our results indicate that the application of the multiplex sgRNA-CRISPR/Cas9 genome editing is efficient tool for mutating more multiple TaSal1 loci in hexaploid wheat.

Malic acid markedly affects watermelon flavor. Reducing the malic acid content can significantly increase the sweetness of watermelon. An effective solution strategy is to reduce watermelon malic acid content through molecular breeding technology. In this study, we measured the TSS and pH of six watermelon varieties at four growth nodes. The TSS content was very low at 10 DAP and accumulated rapidly at 18, 26, and 34 DAP. Three phosphoenolpyruvate carboxykinase (PEPCK) genes of watermelon were identified and analyzed. The ClaPEPCK4 expression was inversely proportional to malate content variations in fruits. In transgenic watermelon plants, overexpressing the ClaPEPCK4 gene, malic acid content markedly decreased. In the knockout transgenic watermelon plants, two SNP mutations and one base deletion occurred in the ClaPEPCK4 gene, with the malic acid content in the leaves increasing considerably and the PEPCK enzyme activity reduced to half of the wild-type. It is interesting that the ClaPEPCK4 gene triggered the closure of leaf stomata under dark conditions in the knockout transgenic plants, which indicated its involvement in stomatal movement. In conclusion, this study provides a gene target ClaPEPCK4 for creating innovative new high-sweetness watermelon varieties.

To feed the world's expanding population, crop breeders need to increase agricultural productivity and expand major crops base. Orphan crops are indigenously important crops with great potential because they are climate resilient, highly nutritious, contain nutraceutical compounds, and can improve the livelihood of smallholder farmers and consumers, but they have received little or no scientific attention. This review article examines several research and developmental strategies for hastening the improvement of these crops so that they can effectively play their role in securing food and nutrition. The integration of both research and developmental approaches will open up modern opportunities for crop improvement. We summarized ways in which advanced tools in phenotyping and genotyping, using high-throughput processes, can be used to accelerate their improvement. Finally, we suggest roles the genebanks can play in improving orphan crops, as the utilization of plant genetic resources is important for the genetic improvement of a crop.

Maize is a major food crop in China, and drought is one of the major abiotic stresses that threaten the growth and development of the crop, seriously affecting the crop yield. 4-coumaric acid coenzyme A ligase (4CL) is a key enzyme in the phenylpropane metabolic pathway, which can regulate the lignin content of the plant and play an important role in the plant's resistance to drought stress, plays an important role in plant resistance to drought stress. In the present study, we screened the differentially expressed up-regulated gene Zm4CL-like9 under drought stress by pre-transcriptome sequencing data (PRJNA793522) in the laboratory, and analyzed the significant up-regulation of Zm4CL-like9 gene in roots under drought stress by qRT-PCR(Real-Time Quantitative Reverse Transcription PCR). The results of prokaryotic expression experiments showed that the protein encoded by the Zm4CL-like9 gene was able to be expressed in prokaryotic cells and could effectively improve the drought tolerance of E. coli. Phenotypic analysis of transgenic Arabidopsis plants under drought stress revealed that seed germination rate, root length, and plant survival after drought rehydration were significantly higher in transgenic Zm4CL-like9 Arabidopsis compared with wild-type Arabidopsis; physiological and biochemical indexes revealed that peroxidase activity, proline (Pro) content, and chlorophyll content were significantly higher in transgenic Arabidopsis compared with wild-type Arabidopsis. Under drought stress, the expression of drought-related genes was significantly up-regulated in transgenic Arabidopsis compared with wild-type Arabidopsis. Taken together, the Zm4CL-like9 gene enhances plant resistance to drought stress by reducing reactive oxygen species accumulation in plants.