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<jats:p>Although drift is not a new issue, it deserves further attention for Unmanned Aerial Spraying Systems (UASS). The use of UASS as a spraying tool for Plant Protection Products is currently explored and applied worldwide. They boast different benefits such as reduced applicator exposure, high operating efficiency and are unconcerned by field-related constraints (ground slope, ground resistance). This review summarizes UASS characteristics, spray drift and the factors affecting UASS drift, and further research that still needs to be developed. The distinctive features of UASS comprise the existence of one or more rotors, relatively higher spraying altitude, faster-flying speed, and limited payload. This study highlights that due to most of these features, the drift of UASS may be inevitable. However, this drift could be effectively reduced by optimizing the structural layout of the rotor and spraying system, adjusting the operating parameters, and establishing a drift buffer zone. Further efforts are still necessary to better assess the drift characteristics of UASS, establish drift models from typical models, crops, and climate environments, and discuss standard methods for measuring UASS drift.</jats:p>

<jats:p>Extensive use of chemical control agents and fungicides typically leads to numerous risks to human health and the environment. Using plant extracts as natural substances represents a dual key for the environment and sustainable food production, as it reduces the input of synthetic pesticides into the environment and/or controls plant pathogens. For the first time, a <jats:italic>Plantago lagopus</jats:italic> ethanolic extract has been characterized and evaluated for its protective and curative effects against <jats:italic>Rhizoctonia solani</jats:italic> in tomato plants. The results showed that <jats:italic>P. lagopus</jats:italic> extract (10 μg/ml) completely inhibited <jats:italic>R. solani</jats:italic> mycelial growth <jats:italic>in vitro</jats:italic>. At 20 days of post fungal inoculation, the results demonstrated that using <jats:italic>P. lagopus</jats:italic> extract (100 μg/ml) <jats:italic>in vivo</jats:italic> enhanced tomato plant growth by significantly increasing shoot and root parameters in protective and curative treatments. Furthermore, the protective and curative treatments significantly reduced the disease index by 18.66 and 38.66%, respectively. Induction of systemic resistance with upregulation of <jats:italic>PR-1</jats:italic> and <jats:italic>PR-2</jats:italic> and a significant increase in the transcriptional levels of <jats:italic>PR-3</jats:italic> and <jats:italic>CHS</jats:italic> in all <jats:italic>P. lagopus</jats:italic> extract-treated tomato plants were reported compared to untreated plants. HPLC analysis showed that the most common polyphenolic components detected in <jats:italic>P. lagopus</jats:italic> extract were rutin (74206.3 mg/kg), naringenin (2388.74 mg/kg), quercetin (1249.13 mg/kg), and <jats:italic>p</jats:italic>-hydroxybenzoic acid (1035.87 mg/kg). In addition, the ellagic acid (798.47 mg/kg), vanillic acid (752.55 mg/kg), catechol (648.89 mg/kg), cinnamic acid (332.51 mg/kg), ferulic acid (296.32 mg/kg), benzoic acid (295.95 mg/kg), and chlorogenic acid (116.63 mg/kg) were also reported. Our study is the first to show that <jats:italic>P. lagopus</jats:italic> extract can help plants fight off <jats:italic>R. solani</jats:italic> fungal infection. Furthermore, the findings imply that using the <jats:italic>P. lagopus</jats:italic> extract as a natural biocontrol agent could be a sustainable strategy to manage plant fungal diseases.</jats:p>

<jats:p>Barley is considered an ideal crop to study cereal genetics due to its close relationship with wheat and diploid ancestral genome. It plays a crucial role in reducing risks to global food security posed by climate change. Genetic variations in the traits of interest in crops are vital for their improvement. DNA markers have been widely used to estimate these variations in populations. With the advancements in next-generation sequencing, breeders could access different types of genetic variations within different lines, with single-nucleotide polymorphisms (SNPs) being the most common type. However, genotyping barley with whole genome sequencing (WGS) is challenged by the higher cost and computational demand caused by the large genome size (5.5GB) and a high proportion of repetitive sequences (80%). Genotyping-by-sequencing (GBS) protocols based on restriction enzymes and target enrichment allow a cost-effective SNP discovery by reducing the genome complexity. In general, GBS has opened up new horizons for plant breeding and genetics. Though considered a reliable alternative to WGS, GBS also presents various computational difficulties, but GBS-specific pipelines are designed to overcome these challenges. Moreover, a robust design for GBS can facilitate the imputation to the WGS level of crops with high linkage disequilibrium. The complete exploitation of GBS advancements will pave the way to a better understanding of crop genetics and offer opportunities for the successful improvement of barley and its close relatives.</jats:p>

<jats:p>Tissue specific promoters are important tools for the precise genetic engineering of crop plants. Four fruit-preferential promoters were examined for their ability to confer a novel fruit trait in transgenic Mexican lime (<jats:italic>Citrus aurantifolia</jats:italic>). The <jats:italic>Ruby</jats:italic> transcription factor activates fruit anthocyanin accumulation within Moro blood orange and has been shown to function in activating anthocyanin accumulation in heterologous plant species. Although the <jats:italic>CitVO1, CitUNK, SlE8</jats:italic>, and <jats:italic>PamMybA</jats:italic> promoters were previously shown to confer strong fruit-preferential expression in transgenic tomato, they exhibited no detectable expression in transgenic Mexican lime trees. In contrast, the <jats:italic>CitWax</jats:italic> promoter exhibited high fruit-preferential expression of <jats:italic>Ruby</jats:italic>, conferring strong anthocyanin accumulation within the fruit juice sac tissue and moderate activity in floral/reproductive tissues. In some of the transgenic trees with high levels of flower and fruit anthocyanin accumulation, juvenile leaves also exhibited purple coloration, but the color disappeared as the leaves matured. We show that the <jats:italic>CitWax</jats:italic> promoter enables the expression of <jats:italic>Ruby</jats:italic> to produce anthocyanin colored fruit desired by consumers. The production of this antioxidant metabolite increases the fruits nutritional value and may provide added health benefits.</jats:p>

<jats:p>Diet is the main intake source of selenium (Se) in the body. Southern Jiangxi is the largest navel orange-producing area in China, and 25.98% of its arable land is Se-rich. However, studies on the Se-rich characteristics and Se dietary evaluation of navel orange fruits in the natural environment of southern Jiangxi have not been reported. This study was large-scale and <jats:italic>in situ</jats:italic> samplings (<jats:italic>n</jats:italic> = 492) of navel oranges in southern Jiangxi with the goal of investigating the coupling relationships among Se, nutritional elements, and quality indicators in fruits and systematically evaluating Se dietary nutrition to the body. The results indicated that the average content of total Se in the flesh was 4.92 μg⋅kg<jats:sup>–1</jats:sup>, and the percentage of Se-rich navel oranges (total Se ≥ 10 μg⋅kg<jats:sup>–1</jats:sup> in the flesh) was 7.93%, of which 66.74% of the total Se was distributed in the pericarp and 33.26% in the flesh. The average content of total Se in the flesh of Yudu County was the highest at 5.71 μg⋅kg<jats:sup>–1</jats:sup>. There was a significant negative correlation (<jats:italic>p</jats:italic> &amp;lt; 0.05) between Se, Cu, and Zn in the Se-rich flesh. According to the Se content in the flesh, the Se dietary nutrition evaluation was carried out, and it was found that the Se-enriched navel orange provided a stronger Se nutritional potential for the human body. These findings will help to identify Se enrichment in navel orange fruit in China’s largest navel orange-producing area and guide the selection of Se-rich soils for navel orange production in the future.</jats:p>

<jats:p>In various plant species, many transcription factors (TFs), such as MYB, bHLH, and WD40, have been identified as regulators of anthocyanin biosynthesis in underground organs. However, the regulatory elements of anthocyanin biosynthesis in the tuberous roots of sweet potato have not been elucidated yet. Here, we selected the purple-fleshed sweet potato cultivar “Zhezi1” (ZZ<jats:italic><jats:sup>P</jats:sup></jats:italic>) and its spontaneous yellow-fleshed mutant “Xinli” (XL<jats:italic><jats:sup>Y</jats:sup></jats:italic>) to investigate the regulatory mechanism of the anthocyanin biosynthesis in the tuberous roots of sweet potato. By analyzing the <jats:italic>IbMYB1</jats:italic> genotype in ZZ<jats:italic><jats:sup>P</jats:sup></jats:italic> and XL<jats:italic><jats:sup>Y</jats:sup></jats:italic>, we found that the <jats:italic>IbMYB1-2</jats:italic>, a MYB TF involved in anthocyanin biosynthesis, was missing in the XL<jats:italic><jats:sup>Y</jats:sup></jats:italic> genome, which might lead to an extreme decrease in anthocyanins in XL<jats:italic><jats:sup>Y</jats:sup></jats:italic>. A comparative transcriptome analysis of ZZ<jats:italic><jats:sup>P</jats:sup></jats:italic> and XL<jats:italic><jats:sup>Y</jats:sup></jats:italic> was conducted to find the TFs involved in anthocyanin biosynthesis in ZZ<jats:italic><jats:sup>P</jats:sup></jats:italic> and XL<jats:italic><jats:sup>Y</jats:sup></jats:italic>. The anthocyanin structural genes were significantly enriched among the differentially expressed genes. Moreover, one MYB activator (<jats:italic>IbMYB1</jats:italic>), one bHLH (<jats:italic>IbbHLH2</jats:italic>), three WRKY activator candidates (<jats:italic>IbWRKY21</jats:italic>, <jats:italic>IbWRKY24</jats:italic>, and <jats:italic>IbWRKY44</jats:italic>), and two MYB repressors (<jats:italic>IbMYB27</jats:italic> and <jats:italic>IbMYBx-ZZ</jats:italic>) were highly expressed in ZZ<jats:italic><jats:sup>P</jats:sup></jats:italic> accompanied with anthocyanin structural genes. We also tested the expression of these TFs in six purple- and two orange-fleshed sweet potato cultivars. Interestingly, most of these TFs were significantly positively correlated with anthocyanin contents in these cultivars. The function of the anthocyanin biosynthesis repression of <jats:italic>IbMYB27</jats:italic> and <jats:italic>IbMYBx-ZZ</jats:italic> was verified through transient co-transformation with <jats:italic>IbMYB1</jats:italic> into tobacco leaves. Further functional verification of the above TFs was conducted by Y2H, BiFC, and dual-luciferase assays. These tests showed that the MYB-bHLH-WD40/MYB-bHLH-WD40-WRKY complex activated the promoter of anthocyanin structural gene <jats:italic>IbDFR</jats:italic> and promoters for <jats:italic>IbWRKY44</jats:italic>, <jats:italic>IbMYB27</jats:italic>, and <jats:italic>IbMYBx-ZZ</jats:italic>, indicating reinforcement and feedback regulation to maintain the level of anthocyanin accumulation in the tuberous roots of purple-fleshed sweet potato. These results may provide new insights into the regulatory mechanism of anthocyanin biosynthesis and accumulation in underground organs of sweet potatoes.</jats:p>

<jats:p><jats:italic>Tetrastigma hemsleyanum</jats:italic> (<jats:italic>T. hemsleyanum</jats:italic>) is a traditional medicinal plant that is widely used in China. Cultivated <jats:italic>T. hemsleyanum</jats:italic> usually encounters cold stress, limiting its growth and quality at key developmental stages. APETALA2 (AP2)/ethylene-responsive factor (ERF) transcription factors (TFs) comprise one of the largest gene superfamilies in plants and are widely involved in biotic and abiotic stresses. To reveal the roles of AP2/ERF TFs during <jats:italic>T. hemsleyanum</jats:italic> development, 70 AP2/ERF TFs were identified in <jats:italic>T. hemsleyanum</jats:italic>. Among them, 18 and 2 TFs were classified into the AP2 and RAV families, respectively. The other 50 TFs belonged to the ERF family and were further divided into the ERF and (dehydration reaction element binding factor) DREB subfamilies. The ERF subfamily contained 46 TFs, while the DREB subfamily contained 4 TFs. Phylogenetic analysis indicated that AP2/ERF TFs could be classified into five groups, in which 10 conserved motifs were confirmed. Several motifs were group- or subgroup-specific, implying that they were significant for the functions of the AP2/ERF TFs of these clades. In addition, 70 AP2/ERF TFs from the five groups were used for an expression pattern analysis under three low-temperature levels, namely, –4, 0, and 4°C. The majority of these AP2/ERF TFs exhibited a positive response to cold stress conditions. Specifically, ThERF5, ThERF31, ThERF46, and ThERF55 demonstrated a more sensitive response to cold stress. Moreover, AP2/ERF TFs exhibited specific expression patterns under cold stress. Transient overexpression and RNA interference indicated that ThERF46 has a specific tolerance to cold stress. These new insights provide the basis for further studies on the roles of AP2/ERF TFs in cold stress tolerance in <jats:italic>T. hemsleyanum</jats:italic>.</jats:p>

<jats:p>The fast and precise detection of dense litchi fruits and the determination of their maturity is of great practical significance for yield estimation in litchi orchards and robot harvesting. Factors such as complex growth environment, dense distribution, and random occlusion by leaves, branches, and other litchi fruits easily cause the predicted output based on computer vision deviate from the actual value. This study proposed a fast and precise litchi fruit detection method and application software based on an improved You Only Look Once version 5 (YOLOv5) model, which can be used for the detection and yield estimation of litchi in orchards. First, a dataset of litchi with different maturity levels was established. Second, the YOLOv5s model was chosen as a base version of the improved model. ShuffleNet v2 was used as the improved backbone network, and then the backbone network was fine-tuned to simplify the model structure. In the feature fusion stage, the CBAM module was introduced to further refine litchi’s effective feature information. Considering the characteristics of the small size of dense litchi fruits, the 1,280 × 1,280 was used as the improved model input size while we optimized the network structure. To evaluate the performance of the proposed method, we performed ablation experiments and compared it with other models on the test set. The results showed that the improved model’s mean average precision (mAP) presented a 3.5% improvement and 62.77% compression in model size compared with the original model. The improved model size is 5.1 MB, and the frame per second (FPS) is 78.13 frames/s at a confidence of 0.5. The model performs well in precision and robustness in different scenarios. In addition, we developed an Android application for litchi counting and yield estimation based on the improved model. It is known from the experiment that the correlation coefficient <jats:italic>R</jats:italic><jats:sup>2</jats:sup> between the application test and the actual results was 0.9879. In summary, our improved method achieves high precision, lightweight, and fast detection performance at large scales. The method can provide technical means for portable yield estimation and visual recognition of litchi harvesting robots.</jats:p>

<jats:p>Rapeseed (<jats:italic>Brassica napus</jats:italic>) is an allopolyploid hybrid (AACC genome) of turnip rape (<jats:italic>B. rapa</jats:italic>, genome: AA) and vegetable cabbage (<jats:italic>B. oleraceae</jats:italic>, genome: CC). Rapeseed oil is one of the main vegetable oils used worldwide for food and other technical purposes. Therefore, breeding companies worldwide are interested in developing rapeseed varieties with high yields and increased adaptation to harsh climatic conditions such as heat and prolonged drought. One approach to studying the mechanism of the epigenetically regulated stress response is to analyze the transcriptional changes it causes. In addition, comparing the expression of certain genes between stress- and non-stress-tolerant varieties will help guide breeding in the desired direction. Quantitative reverse transcription PCR (RT-qPCR) has been intensively used for gene expression analysis for several decades. However, the transfer of this method from model plants to crop species has several limitations due to the high accumulation of secondary metabolites, the higher water content in some tissues and therefore problems with their grinding and other factors. For allopolyploid rapeseed, the presence of two genomes, often with different levels of expression of homeologous genes, must also be considered. In this study, we describe the optimization of transcriptional RT-qPCR analysis of low-expression epigenetic genes in rapeseed, using <jats:italic>Kinetochore Null2</jats:italic> (<jats:italic>KNL2</jats:italic>), a regulator of kinetochore complex assembly, as an example. We demonstrated that a combination of various factors, such as tissue homogenization and RNA extraction with TRIzol, synthesis of cDNA with gene-specific primers, and RT-qPCR in white plates, significantly increased the sensitivity of RT-qPCR for the detection of <jats:italic>BnKNL2A</jats:italic> and <jats:italic>BnKNL2C</jats:italic> gene expression.</jats:p>

<jats:p>Increasing temperatures, heat waves, and reduction of annual precipitation are all the expressions of climate change (CC), strongly affecting bread wheat (<jats:italic>Triticum aestivum</jats:italic> L.) grain yield in Southern Europe. Being temperature the major driving force of plants’ phenological development, these variations also have effects on wheat phenology, with possible consequences on grain quality, and gluten protein accumulation. Here, through a case study in the Bolognese Plain (North of Italy), we assessed the effects of CC in the area, the impacts on bread wheat phenological development, and the consequences on grain gluten quality. The increasing trend in mean annual air temperature in the area since 1952 was significant, with a breakpoint identified in 1989, rising from 12.7 to 14.1°C, accompanied by the signals of increasing aridity, i.e., increase in water table depth. Bread wheat phenological development was compared in two 15-year periods before and after the breakpoint, i.e., 1952–1966 (past period), and 2006–2020 (present period), the latest characterized by aridity and increased temperatures. A significant shortening of the chronological time necessary to reach the main phenological phases was observed for the present period compared to the past period, finally shortening the whole life cycle. This reduction, as well as the higher temperature regime, affected gluten accumulation during the grain-filling process, as emerged analyzing gluten composition in grain samples of the same variety harvested in the area both before and after the breakpoint in temperature. In particular, the proportion of gluten polymers (i.e., gliadins, high and low molecular weight glutenins, and their ratio) showed a strong and significant correlation with cumulative growing degree days (CGDDs) accumulated during the grain filling. Higher CGDD values during the period, typical of CC in Southern Europe, accounting for higher temperature and faster grain filling, correlated with gliadins, high molecular weight glutenins, and their proportion with low molecular weight glutenins. In summary, herein reported, data might contribute to assessing the effects of CC on wheat phenology and quality, representing a tool for both predictive purposes and decision supporting systems for farmers, as well as can guide future breeding choices for varietal innovation.</jats:p>