Predicting wheat gluten concentrations in potato starch using GPR and SVM models built by terahertz time-domain spectroscopy.

The purpose of this study was for the first time to explore the feasibility of terahertz (THz) spectral imaging for the detection of gluten contents in food samples. Based on the obtained 80 THz spectrum data, Gaussian process regression (GPR) and support vector machine (SVM) models were established to predict wheat gluten concentrations in 40 potato starch mixture samples. The prediction performances of GPR and SVM obtained were R2 = 0.859 and RMSE = 0.070, and R2 = 0.715 and RMSE = 0.101 in the gluten concentration range of 1.3%-100%, respectively, showing that the linear SVM algorithm had better prediction performance. The results indicated that THz spectral imaging combined with GPR could be used to predict the gluten content in food samples. It is thus hoped that this research should provide a novel technique for gluten content detection to ensure gluten-free food samples.

Microwave-induced rapid 4D change in color of 3D printed apple/potato starch gel with red cabbage juice-loaded WPI/GA mixture.

This study aimed to explore the feasibility of utilizing microparticle mixture (MCPs) comprised of whey protein isolate (WPI), gum Arabic (GA), and freeze-dried red cabbage juice (FDRCJ) as a smart material to realize a rapid color change of 3D printed apple/potato starch gel in response to microwave heating stimulation. The particle size, morphology and thermal stability of WPI/FDRCJ/GA microparticles were examined. Then, the rheology, texture properties and printability of Apple/potato starch gel affected by different concentrations of WPI/FDRCJ/GA microparticles (0, 15, 30, 45, 60% (w/w)) were studied. Results showed that the WPI/FDRCJ/GA microparticles were more thermally stable than pure materials, indicating that the heat-sensitive anthocyanin and other compounds present in FDRCJ were effectively protected by the wall materials (WPI/GA). Moreover, the addition of various microparticle concentrations decreased the samples' mechanical properties but had no significant influence on their loss modulus, viscosity, or printing accuracy. As the microwave heating time increased, the lightness (L*) and yellowness (b*) of microparticle-added samples decreased while the redness (a*) significantly increased (p < 0.05), resulting in a gradual color change from yellow/brown to red. These findings could be useful to produce novel colorful and appealing 4D healthy food products that stimulate consumer appetite.

Genome-Wide Analysis of the Membrane Attack Complex and Perforin Genes and Their Expression Pattern under Stress in the Solanaceae.

The Membrane Attack Complex and Perforin (MACPF) proteins play a crucial role in plant development and adaptation to environmental stresses. Heretofore, few MACPF genes have been functionally identified, leaving gaps in our understanding of MACPF genes in other plants, particularly in the Solanaceae family, which includes economically and culturally significant species, such as tomato, potato, and pepper. In this study, we have identified 26 MACPF genes in three Solanaceae species and in the water lily, which serves as the base group for angiosperms. Phylogenetic analysis indicates that angiosperm MACPF genes could be categorized into three distinct groups, with another moss and spikemoss lineage-specific group, which is further supported by the examination of gene structures and domain or motif organizations. Through inter-genome collinearity analysis, it is determined that there are 12 orthologous SolMACPF gene pairs. The expansion of SolMACPF genes is primarily attributed to dispersed duplications, with purifying selection identified as the principal driving force in their evolutionary process, as indicated by the ω values. Furthermore, the analysis of expression patterns revealed that Solanaceae genes are preferentially expressed in reproductive tissues and regulated by various environmental stimuli, particularly induced by submergence. Taken together, these findings offer valuable insights into and a fresh perspective on the evolution and function of SolMACPF genes, thereby establishing a foundation for further investigations into their phenotypic and functional characteristics.

Pseudomonas PA14H7: Identification and Quantification of the 7-Hydroxytropolone Iron Complex as an Active Metabolite against Dickeya, the Causal Agent of Blackleg on the Potato Plant.

Soft rot Pectobacteriaceae (SRP), such as Pectobacterium and Dickeya, are phytopathogenic agents responsible for blackleg disease on several crops, such as potatoes, affecting the yield and depressing the seed production quality. However, neither conventional nor biocontrol products are available on the market to control this disease. In this study Pseudomonas PA14H7, a bacteria isolated from potato rhizosphere, was selected as a potential antagonist agent against Dickeya solani. In order to understand the mechanism involved in this antagonism, we managed to identify the main active molecule(s) produced by PA14H7. Cell-free supernatant (CFS) of PA14H7 cultures were extracted and analyzed using LC-MS, GC-MS, and NMR. We further correlated the biological activity against Dickeya solani of extracted CFS-PA14H7 to the presence of 7-hydroxytropolone (7-HT) complexed with iron. In a second time, we have synthesized this molecule and determined accurately using LC-UV, LC-MS, and GC-MS that, after 48 h incubation, PA14H7 released, in its CFS, around 9 mg/L of 7-HT. The biological activities of CFS-PA14H7 vs. synthetic 7-HT, at this concentration, were evaluated to have a similar bacteriostatic effect on the growth of Dickeya solani. Even if 7-HT is produced by other Pseudomonas species and is mostly known for its antibacterial and antifungal activities, this is the first description of its involvement as an effective molecule against pectinolytic bacteria. Our work opens the way for the comprehension of the mode of action of PA14H7 as a biocontrol agent against potato blackleg.

Impact of dormancy periods on some physiological and biochemical indices of potato tubers.

Background: Storage of potato tubers is an essential stage of the supply chain, from farm to consumer, to efficiently match supply and demand. However, the quality and yield of potatoes are influenced by physiological changes during storage. Methods: This study tested the physiological and biochemical indices in three potato varieties (YunSu 108, YunSu 304 and YunSu 306) during their dormancy periods. Results: Three potato varieties with different dormancy periods were used to follow changes in starch, protein and several enzymes during storage. The starch and sugar content of the long-dormant variety (YunSu 108, LDV) were stable, whereas those of the short-dormant variety (YunSu 306, SDV) were variable. Starch synthase activity in the three varieties was initially high, then decreased; the starch content of LDV was relatively stable, that of the medium-dormant variety (YunSu 304, MDV) increased with storage time and peaked at sprouting, and that of SDV was low but variable. The sucrose synthase activity of LDV was significantly higher (p < 0.05) than MDV and SDV in the middle storage period. Two spikes were observed in the invertase activity of SDV, whereas those of MDV and LDV were stable. The reducing sugar content of LDV increased significantly before sprouting, that of MDV slowly decreased and that of SDV dropped sharply. During the whole storage period, pectinase activity in LDV did not change significantly, whereas pectinase in MDV and SDV decreased. The cellulase and protein contents initially increased and then decreased in LDV, and steadily decreased in MDV and SDV. Conclusion: The metabolic indices related to starch and sugar in the LDV were relatively stable during storage, whereas those of the SDV varied greatly. SDV showed increased sucrose, reducing sugars and cellulose; LDV PCA plots clustered in the positive quadrant of PC1 and the negative quadrant of PC2, with increased protein, sucrose synthase and starch; MDV had increased soluble starch synthase.

Postharvest starch and sugars adjustment in potato tubers of wide-ranging dormancy genotypes subjected to various sprout forcing techniques.

The development of an efficient, safe, and environment-friendly technique to terminate tuber dormancy in potatoes (Solanum tuberosum L.) is of great concern due to the immense scope of multiple cropping all over the globe. The breakage of tuber dormancy has been associated with numerous physiological changes, including a decline in the level of starch and an increase in the levels of sugars during storage of freshly harvested seed potatoes, although their consistency across genotypes and various dormancy-breaking techniques have not yet been fully elucidated. The purpose of the present research is to assess the efficacy of four different dormancy-breaking techniques, such as soaking in 90, 60, or 30 mg L-1 solutions of benzyl amino purine (BAP) and 30, 20, or 10 mg L-1 gibberellic acid (GA3) alone and in the combination of optimized concentrations; cold pre-treatment at 6, 4, or 2 °C; electric shock at 80, 60, 40, or 20 Vs; and irradiation at 3.5, 3, 2.5, 2, 1.5, or 1 kGy on the tuber dormancy period and sprout length of six genotypes. Furthermore, the changes that occurred in tuber weight and endogenous starch, sucrose, fructose, and glucose contents in experimental genotypes following the application of these techniques were also examined. Overall, the most effective technique to terminate tuber dormancy and hasten spout growth was the combined application of BAP and GA3, which reduced the length of dormancy by 9.6 days compared to the untreated control, following 6.7 days of electric current, 4.4 days of cold pre-treatment, and finally irradiation (3.3 days). The 60 mg L-1 solution of BAP greatly reduced the dormancy period in all genotypes but did not affect the sprout length at all. The genotypes showed a weak negative correlation (r = - 0.4) (P < 0.05) of endogenous starch contents with dormancy breakage and weight loss or a moderate (r = - 0.5) correlation with sprout length, but a strong positive correlation (r = 0.8) of tuber glucose, fructose, and sucrose contents with dormancy breakage and weight loss. During 3 weeks of storage, sprouting commencement and significant weight loss occurred as tuber dormancy advanced towards breakage due to a reduction in starch and an increase in the sucrose, fructose, and glucose contents of the tubers. These findings could be advantageous for postponing or accelerating seed potato storage as well as investigating related physiological research in the future.

High-efficiency green management of potato late blight by a self-assembled multicomponent nano-bioprotectant.

Potato late blight caused by Phytophthora infestans is a devastating disease worldwide. Unlike other plant pathogens, double-stranded RNA (dsRNA) is poorly taken up by P. infestans, which is a key obstacle in using dsRNA for disease control. Here, a self-assembled multicomponent nano-bioprotectant for potato late blight management is designed based on dsRNA and a plant elicitor. Nanotechnology overcomes the dsRNA delivery bottleneck for P. infestans and extends the RNAi protective window. The protective effect of nano-enabled dsRNA against infection arises from a synergistic mechanism that bolsters the stability of dsRNA and optimizes its effective intracellular delivery. Additionally, the nano-enabled elicitor enhances endocytosis and amplifies the systemic defense response of the plants. Co-delivery of dsRNA and an elicitor provides a protective effect via the two aspects of pathogen inhibition and elevated plant defense mechanisms. The multicomponent nano-bioprotectant exhibits superior control efficacy compared to a commercial synthetic pesticide in field conditions. This work proposes an eco-friendly strategy to manage devastating plant diseases and pests.

The interaction of nicotinic acetylcholine receptor subunits Ldα3, Ldα8 and Ldß1 with neonicotinoids in Colorado potato beetle, Leptinotarsa decemlineata.

The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), is an extremely destructive notifiable quarantine pest. Over the last two decades, neonicotinoid insecticides, particularly thiamethoxam and imidacloprid, have been used to control it in Xinjiang, and local field populations have developed different levels of resistance in consequence. However, the contributions of nicotinic acetylcholine receptors (nAChRs) to neonicotinoid resistance are currently poorly understood in CPB. Previous studies have shown that nAChRα1, α3, α8 and ß1 are major target subunits for neonicotinoids in some model and important agricultural insects including nAChRα1 subunit of L. decemlineata (Ldα1). In this study, the expression levels of Ldα3, Ldα8 and Ldß1 following 72 h of treatments with median lethal doses of thiamethoxam and imidacloprid were compared using real-time quantitative PCR. These genes were then individually and simultaneously knocked down with Ldα1 by RNA interference (RNAi) using a double-stranded RNA (dsRNA) feeding method for six days to explore their roles in CPB susceptibility to imidacloprid and thiamethoxam. The results showed that the expressions of Ldα3, Ldα8 and Ldß1 were significantly decreased by 36.99-74.89% after thiamethoxam and imidacloprid treatments, compared with the control. The significant downregulation of the target genes resulting from RNAi significantly reduced the mortality of adults exposed to thiamethoxam and imidacloprid by 34.53% -56.44% and 28.78%-43.93%, respectively. Furthermore, the adult survival rates were not affected by every dsRNA-feeding treatment, while the body weight of the test adults significantly deceased after four and six days of individual gene RNAi. This study showed that Ldα3, Ldα8 and Ldß1 are down-regulated by thiamethoxam and imidacloprid and play important roles in the tolerance of CPB to neonicotinoids.

Gradual Analytics of Starch-Interacting Proteins Revealed the Involvement of Starch-Phosphorylating Enzymes during Synthesis of Storage Starch in Potato (Solanum tuberosum L.) Tubers.

The complete mechanism behind starch regulation has not been fully characterized. However, significant progress can be achieved through proteomic approaches. In this work, we aimed to characterize the starch-interacting proteins in potato (Solanum tuberosum L. cv. Desiree) tubers under variable circumstances. Starch-interacting proteins were extracted from developing tubers of wild type and transgenic lines containing antisense inhibition of glucan phosphorylases. Further, proteins were separated by SDS-PAGE and characterized through mass spectrometry. Additionally, starch-interacting proteins were analyzed in potato tubers stored at different temperatures. Most of the proteins strongly interacting with the potato starch granules corresponded to proteins involved in starch metabolism. GWD and PWD, two dikinases associated with starch degradation, were consistently found bound to the starch granules. This indicates that their activity is not only restricted to degradation but is also essential during storage starch synthesis. We confirmed the presence of protease inhibitors interacting with the potato starch surface as previously revealed by other authors. Starch interacting protein profiles of transgenic tubers appeared differently from wild type when tubers were stored under different temperatures, indicating a differential expression in response to changing environmental conditions.

Dissected Leaf 1 encodes an MYB transcription factor that controls leaf morphology in potato.

KEY MESSAGE: The transcription factor StDL1 regulates dissected leaf formation in potato and the genotype frequency of recessive Stdl1/Stdl1, which results in non-dissected leaves, has increased in cultivated potatoes. Leaf morphology is a key trait of plants, influencing plant architecture, photosynthetic efficiency and yield. Potato (Solanum tuberosum L.), the third most important food crop worldwide, has a diverse leaf morphology. However, despite the recent identification of several genes regulating leaf formation in other plants, few genes involved in potato leaf development have been reported. In this study, we identified an R2R3 MYB transcription factor, Dissected Leaf 1 (StDL1), regulating dissected leaf formation in potato. A naturally occurring allele of this gene, Stdl1, confers non-dissected leaves in young seedlings. Knockout of StDL1 in a diploid potato changes the leaf morphology from dissected to non-dissected. Experiments in N. benthamiana and yeast show that StDL1 is a transcriptional activator. Notably, by calculating the genotype frequency of the Stdl1/Stdl1 in 373-potato accessions, we found that it increases significantly in cultivated potatoes. This work reveals the genetic basis of dissected leaf formation in potato and provides insights into plant leaf morphology.

Comparative Chemical Characterization of Potato Powders Using 1H NMR Spectroscopy and Chemometrics.

This study presents the metabolic profiling of potato powders obtained through various processing procedures and commercially available potato powders. The metabolic fingerprinting was conducted using 1H NMR-based metabolomics coupled with machine learning projections. The results indicate hot air-dried potatoes have higher fumarate, glucose, malate, asparagine, choline, gamma aminobutyric acid (GABA), alanine, lactate, threonine, and fatty acids. In comparison, steam-cooked potatoes have higher levels of phenylalanine, sucrose, proline, citrate, glutamate, and valine. Moreover, the contents of metabolites in processed potatoes in this study were higher than those found in commercial potato powders, regardless of the drying or cooking methods used. The results indicate that a new processing technique may be developed to improve the nutritional value of potatoes.

Ethanol fumigation combined with modified atmosphere packaging delays potato greening under light.

Potato greening under light causes post-harvest loss and compromises progress being made in the potato industry. In this study, we investigated the inhibiting effects of ethanol fumigation treatment on potato greening and water loss under light. This paper also examined the different treatments on the relationship between starch granule size and potato greening. Our results suggested that ethanol fumigation combined with modified atmosphere packaging have an effective in improving the overall visual quality and maintained a higher a* value and lower chlorophyll concentration. Ethanol fumigation combined with modified atmosphere packaging treatment deterred greening and water loss compared to the alone treatment. This was due to the larger starch granule size and fewer grana lamellae around the amyloplasts. Our results provide an effectively strategy that treating potatoes with 600 µL L-1 ethanol combined with modified atmosphere packaging to delay potato greening and explain the underlying mechanism of ethanol inhibition of potato greening.

Solanum americanum genome-assisted discovery of immune receptors that detect potato late blight pathogen effectors.

Potato (Solanum tuberosum) and tomato (Solanum lycopersicon) crops suffer severe losses to late blight caused by the oomycete pathogen Phytophthora infestans. Solanum americanum, a relative of potato and tomato, is globally distributed and most accessions are highly blight resistant. We generated high-quality reference genomes of four S. americanum accessions, resequenced 52 accessions, and defined a pan-NLRome of S. americanum immune receptor genes. We further screened for variation in recognition of 315P. infestans RXLR effectors in 52 S. americanum accessions. Using these genomic and phenotypic data, we cloned three NLR-encoding genes, Rpi-amr4, R02860 and R04373, that recognize cognate P. infestans RXLR effectors PITG_22825 (AVRamr4), PITG_02860 and PITG_04373. These genomic resources and methodologies will support efforts to engineer potatoes with durable late blight resistance and can be applied to diseases of other crops.

Mairá-Potato (Casimirella sp.): Botanical, Food, Pharmacological, and Phytochemical Aspects.

Millions of people in the world live in food insecurity, so identifying a tuber with characteristics capable of meeting the demand for food and also identifying active compounds that can be used to minimize harm to human health is of great value. The aim was to carry out a review based on systematic review tools and the main objective was to seek information on botanical, food, pharmacological, and phytochemical aspects of Casimirella sp. and propose possible applications. This review showed papers that addressed botanical, food, pharmacological, and phytochemical aspects of the Mairá-potato and presented suggestions for using this tuber allied to the information described in the works found in the Google Academic, Scielo, Science Direct, Scopus, PubMed, and Web of Science databases. This review synthesized knowledge about the Mairá-potato that can contribute to the direction of further research on the suggested technological applications, both on the use of this tuber as a polymeric material and its use as biomaterial, encapsulation, bioactive use, and 3D printing, because this work collected information about this non-conventional food plant (PANC) that shows great potential for use in various areas of study.

Breeding strategies for late blight resistance in potato crop: recent developments.

Late blight (LB) is a serious disease that affects potato crop and is caused by Phytophthora infestans. Fungicides are commonly used to manage this disease, but this practice has led to the development of resistant strains and it also poses serious environmental and health risks. Therefore, breeding for resistance development can be the most effective strategies to control late blight. Various Solanum species have been utilized as a source of resistance genes to combat late blight disease. Several potential resistance genes and quantitative resistance loci (QRLs) have been identified and mapped through the application of molecular techniques. Furthermore, molecular markers closely linked to resistance genes or QRLs have been utilized to hasten the breeding process. However, the use of single-gene resistance can lead to the breakdown of resistance within a short period. To address this, breeding programs are now being focused on development of durable and broad-spectrum resistant cultivars by combining multiple resistant genes and QRLs using advanced molecular breeding tools such as marker-assisted selection (MAS) and cis-genic approaches. In addition to the strategies mentioned earlier, somatic hybridization has been utilized for the development and characterization of interspecific somatic hybrids. To further broaden the scope of late blight resistance breeding, approaches such as genomic selection, RNAi silencing, and various genome editing techniques can be employed. This study provides an overview of recent advances in various breeding strategies and their applications in improving the late blight resistance breeding program.

The Retinoblastoma-related gene RBL901 can trigger drought response actions in potato.

KEY MESSAGE: This study provided new insights into response of potato to drought stress.

Foliar Application of Chelated Sugar Alcohol Calcium Improves Photosynthesis and Tuber Quality under Drought Stress in Potatoes (Solanum tuberosum L.).

Drought stress is a major threat to sustainable crop production worldwide. Despite the positive role of calcium (Ca2+) in improving plant drought tolerance in different crops, little attention has been paid to its role in mitigating drought stress in potatoes. In the present study, we studied the effect of foliar chelated sugar alcohol calcium treatments on two potato cultivars with different drought responses applied 15 and 30 days after limiting soil moisture. The results showed that the foliar application of calcium treatments alleviated the SPAD chlorophyll loss of the drought-sensitive cultivar 'Atlantic' (Atl) and reduced the inhibition of photosynthetic parameters, leaf anatomy deformation, and MDA and H2O2 content of both cultivars under drought stress. The Ca2+ treatments changed the expression of several Calcium-Dependent Protein Kinase (StCDPK) genes involved in calcium sensing and signaling and significantly increased antioxidant enzyme activities, average tuber weight per plant, and tuber quality of both cultivars. We conclude that calcium spray treatments improved the drought tolerance of both potato cultivars and were especially effective for the drought-sensitive cultivar. The present work suggests that the foliar application of calcium is a promising strategy to improve commercial potato yields and the economic efficiency of potato production under drought stress conditions.

Cas13d-mediated multiplex RNA targeting confers a broad-spectrum resistance against RNA viruses in potato.

CRISPR-Cas systems endow the bacterial and archaeal species with adaptive immune mechanisms to fend off invading phages and foreign plasmids. The class 2 type VI CRISPR/Cas effector Cas13d has been harnessed to confer the protection against RNA viruses in diverse eukaryotic species. However a vast number of different viruses can potentially infect the same host plant resulting in mixed infection, thus necessitating the generation of crops with broad-spectrum resistance to multiple viruses. Here we report the repurposing of CRISPR/Cas13d coupled with an endogenous tRNA-processing system (polycistronic tRNA-gRNA, PTG) to target the multiple potato RNA viruses. Expression of Cas13d and four different gRNAs were observed in transgenic potato lines expressing the Cas13d/PTG construct. We show that the Cas13d/PTG transgenic plants exhibit resistance to either PVY, PVS, PVX or PLRV alone or two/three viruses simultaneously by reducing viral accumulation in plant cells. In sum, our findings provide an efficient strategy for engineering crops that can simultaneously resist infection by multiple RNA viruses.

Acidogenic fermentation of potato peel waste for volatile fatty acids production: Effect of initial organic load.

As a renewable carbon source produced from organic wastes by acidogenic fermentation, volatile fatty acids (VFAs) are important intermediates in chemical and biological fields and beneficial to resource recovery and carbon neutrality. Maximizing VFA production by some strategies without additional chemicals is critical to increasing economic and environmental benefits. In this study, the effects of initial organic load (OL) on the performance of VFA production, variations of intermediate metabolites, and the thermogravimetric properties of potato peel waste (PPW) during batch acidogenic fermentation were studied. The results showed that the concentration of VFAs increased with the increase of initial OL, while the VFA yield decreased with the increase of initial OL. When the initial OL was in the range of 28.4 g VS/L-91.3 g VS/L, the fermentation type of PPW was butyric acid fermentation. The highest butyric acid proportion of 61.3% was achieved with the initial OL of 71.5 g VS/L. With the increase of initial OL, the proportion of acetic acid and the utilization rate of protein in the PPW decreased. VFAs were produced from proteins and carbohydrates in the early stage and mainly produced from carbohydrates in the later stage. The production efficiency of VFA was relatively high with the initial OL of 71.5 g VS/L, because more easily-biodegradable compounds were solubilized. The results showed that suitably increased initial OL could accelerate acidogenesis, reduce hydrolysis time, and increase the proportion of butyric acid. The findings in this work suggest that PPW is a promising feedstock for butyric acid biosynthesis and appropriate initial OL is beneficial to VFA production.

Identification of sex-specific markers based on gene expression in adult Colorado potato beetles.

The Colorado potato beetle, Leptinotarsa decemlineata, (Coleoptera: Chrysomelidae) is an economically important pest insect of potatoes. Understanding how the mechanisms driving its invasiveness vary between sexes will be critical for developing modern control methods. However, the currently available methods for sexing adult Colorado potato beetles are either inefficient or unsuitable for projects that require RNA as an input, like those measuring gene expression. Therefore, the development of simple molecular tools that are tailored to these studies is important. In this study, we used publicly available RNA-seq data to select 5 candidate genes for sex-specific markers in adult Colorado potato beetles. We confirmed that our 5 marker candidates exhibit a sex-specific expression pattern and can be used as PCR markers for sex determination. This method of sex detection will allow researchers to distinguish the sex of the individual with a simple PCR reaction using cDNA as the template and assign sex to RNA-seq samples post hoc.