Search Results (240)

The impact of insect pests on the yield and quality of rice is extremely significant, and accurate detection of insect pests is of crucial significance to safeguard rice production. However, traditional manual inspection methods are inefficient and subjective, while existing machine learning-based approaches still suffer from limited generalization and suboptimal accuracy. To address these challenges, this study proposes an improved rice pest detection model, MTD-YOLO, based on the YOLOv8 framework. First, the original backbone is replaced with MobileNetV3, which leverages optimized depthwise separable convolutions and the Hard-Swish activation function through neural architecture search, effectively reducing parameters while maintaining multiscale feature extraction capabilities. Second, a Cross Stage Partial module with Triplet Attention (C2f-T) module incorporating Triplet Attention is introduced to enhance the model’s focus on infested regions via a channel-patial dual-attention mechanism. In addition, a Dynamic Head (DyHead) is introduced to adaptively focus on pest morphological features using the scale–space–task triple-attention mechanism. The experiments were conducted using two datasets, Rice Pest1 and Rice Pest2. On Rice Pest1, the model achieved a precision of 92.5%, recall of 90.1%, mAP@0.5 of 90.0%, and mAP@[0.5:0.95] of 67.8%. On Rice Pest2, these metrics improved to 95.6%, 92.8%, 96.6%, and 82.5%, respectively. The experimental results demonstrate the high accuracy and efficiency of the model in the rice pest detection task, providing strong support for practical applications. Full article

We clarified the effect of wheat straw return combined with microbial agents on rice yield and soil properties. A field experiment was conducted using hybrid indica rice ‘Chuankangyou 2115’ and five treatments: no wheat straw return (T₁), wheat straw return alone (T₂), T₂+ microbial agent application (Bacillus subtilis/Trichoderma harzianum = 1:1) (T₃); T₂+ microbial agent application (Bacillus subtilis/Trichoderma harzianum = 3:1) (T₄); T₂+ microbial agent application (Bacillus subtilis/Trichoderma harzianum = 1:3) (T₅). T₂–T₅ significantly increased dry matter accumulation, soil total N, ammonium N, nitrate N, and organic matter, improving yield by 3.81–26.63%. T₃ exhibited the highest yield increases in two consecutive years. At the jointing and heading stages, Penicillium and Saitozyma dominated under T₃ and positively correlated with dry matter, yield, and nitrogen levels. Straw return combined with Bacillus subtilis and Trichoderma harzianum (20 g m⁻² each) enhanced soil nitrogen availability and dry matter accumulation and translocation. Our findings guide efficient straw utilization, soil microbial regulation, and sustainable high-yield rice production. Full article

Vibrational spectroscopy, including Raman and near-infrared techniques, enables the non-destructive evaluation of starch gelatinization, head rice yield, and aroma-active volatile compounds in parboiled rice subjected to varying soaking and drying conditions. Raman and NIR spectra were collected for rice samples processed under different conditions and integrated with reference analyses to develop and validate partial least squares regression and artificial neural network models. The optimized PLSR model demonstrated strong predictive performance, with R² values of 0.9406 and 0.9365 for SG and HRY, respectively, and residual predictive deviations of 3.98 and 3.75 using Raman effective wavelengths. ANN models reached R² values of 0.97 for both SG and HRY, with RPDs exceeding 4.2 using NIR effective wavelengths. In the aroma compound analysis, p-Cymene exhibited the highest predictive accuracy, with R² values of 0.9916 for calibration, and 0.9814 for cross-validation. Other volatiles, such as 1-Octen-3-ol, nonanal, benzaldehyde, and limonene, demonstrated high predictive reliability (R² ≥ 0.93; RPD > 3.0). Conversely, farnesene, menthol, and menthone showed poor predictability (R² < 0.15; RPD < 0.4). Principal component analysis revealed that the first principal component explained 90% of the total variance in the Raman dataset and 71% in the NIR dataset. Hotelling’s T² analysis identifies influential outliers and enhances model robustness. Optimal processing conditions for achieving maximum HRY and SG values were determined at 65 °C soaking for 180 min, followed by drying at 70 °C. This study underscores the potential of integrating vibrational spectroscopy with machine learning techniques and targeted wavelength selection for the high-throughput, accurate, and scalable quality evaluation of parboiled rice. Full article

This study evaluated the effects of one-time application of controlled-release fertilizer (CRF) on rice (Oryza sativa L.) grain yield, grain quality, and agronomic nitrogen use efficiency (ANUE, ANUE (kg/kg) = (Grain yield with N application − grain yield without N application)/N application amount) in coastal saline soils. A two-year field experiment (2023–2024) was conducted using two rice varieties (Nanjing 5718 and Yongyou 4953) under four nitrogen treatments: N0 (no nitrogen fertilization), N1 (270 kg·hm⁻², with a ratio of 5:1:2:2 at 1-day before transplanting, 7-day after transplanting, panicle initiation, and penultimate-leaf appearance stage, respectively), N2 (270 kg·hm⁻², one-time application at 1-day before transplanting as 50% CRF with 80-day release period + 50% urea), and N3 (270 kg·hm⁻², 50% one-time application of CRF with 120-day release period at the seedling stage + 50% urea at 1-day before transplanting). Compared with N1, the N3 treatment significantly increased grain yield by 10.2% to 12.9% and improved ANUE by 18.5% to 51.6%. It also improved processing quality (higher brown rice, milled rice, and head rice rates), appearance quality (reduced chalkiness degree and chalky rice percentage), and taste value (by 19.3% to 31.2%). These improvements were associated with lower amylose, protein, and soluble sugar contents and favorable changes in starch composition and pasting properties. While N2 slightly improved some quality traits, it significantly reduced yield and ANUE. Correlation analysis revealed that starch and protein composition, as well as pasting properties, were significantly associated with taste value and related attributes such as appearance, stickiness, balance degree, and hardness. Overall, one-time application of CRF with a 120-day release period at the seedling stage, combined with basal urea, offers an effective strategy to boost yield, quality, and ANUE in coastal saline rice systems. Full article

Above-ground biomass (AGB) is an important factor in crop yield. However, most AGB estimation methods for crops with conspicuous spikes, such as rice and sorghum, can achieve high accuracy during the vegetative stage but low accuracy during the reproductive stage. In this study, we explored an AGB estimation model throughout the entire growth period. Firstly, we divided the growth period of crops into two stages—before heading and after heading—and adopted different strategies according to the characteristics of the different stages. Before heading, we estimated AGB by multiplying the multi-spectral vegetation index (VI) and the crop canopy height (H) square. After heading, we added spectral absorption characteristic parameters to characterize spike biomass and used a multiple linear regression model. This model can accurately estimate AGB in both rice and sorghum throughout the entire growth period, which has a coefficient of determination (R²) above 0.88 and the relative root mean square error (rRMSE) below 20.13% in both crops. Compared with the direct estimation of AGB throughout the entire growth period using H² × VI, this model effectively improved the accuracy of AGB estimation for crops with conspicuous spikes in the reproductive stage, which can provide reliable information for evaluating crop growth at plot scale. Full article

The Yangtze River Delta (YRD) is one of the most important japonica rice planting areas in China. Balancing the resistance, yield, and quality has always been a core issue in rice breeding due to the negative correlation among these three factors, while the broad-spectrum blast resistance gene Piz is closely linked with Hd1, the major gene regulating days to heading (DTH), and a precise combination of their beneficial alleles plays a key role in synchronously improving blast resistance and the regional adaptability of japonica rice in YRD. In this study, using the backcross progeny population derived from backbone parent ZD9471 and W1063, two alleles of Hd1 were identified. Then, through molecular marker-assisted selection combined with Green Super Rice 40K (GSR40K) chip-based screening, six introgression lines (ILs) with two different alleles combinations of Hd1 and Pigm were obtained. An evaluation of the blast resistance, yield, and quality traits showed that compared with the recipient parent, the panicle blast resistance of ILs was significantly enhanced; the grain number per panicle increased consistently with the delaying of the growth period, leading to higher yield in the ILs; the grain quality were synchronously improved. Two representative lines with similar genetic backgrounds but a significantly different regional adaptability, exhibiting a good blast resistance, high yield, and prominent quality were approved and demonstrated promising application prospects. Full article

The Ghd7 gene in rice plays a crucial role in determining heading date, plant height, and grain yield. However, the variations in Ghd7 and their functional implications across different rice accessions are not fully understood. Based on the release of a large amount of rice genome data in recent years, we investigated Ghd7 through pan-genome analysis of 372 diverse rice varieties and figured out the structural variations (SVs) in the Ghd7 locus. However, due to the high cost of pan-genomes, most genomes are based on next-generation sequencing (NGS) data now. Therefore, we developed a method for identifying SVs using NGS data and Polymerase Chain Reaction (PCR) based on the results of pan-genome analysis and identified 977 accessions carrying such SVs of Ghd7. Furthermore, we identified 46 single-nucleotide polymorphisms (SNPs) and one insertion-deletion (InDel) in the coding region of Ghd7. They are classified into 49 haplotypes. Notably, a splice-site mutation in haplotype H6 causes aberrant mRNA splicing. Using prime editing (PE) technology, we successfully restored the functional of Ghd7 in Yixiang 1B (YX1B), delaying the heading date by approximately 16 days. This modification synchronized the heading date between YX1B and the restorer line Yahui 2115 (YH2115R), enhancing the hybrid rice seed production efficiency. In conclusion, our findings highlight the potential of integrating pan-genomics and precision gene editing to accelerate crop improvement and enhance agronomic traits. Full article

Rice hulls, a traditional ingredient in Chinese light-flavor Baijiu, contribute to bran and furfural flavors but may adversely affect the aroma and taste. This study explores fresh pomegranate peel as a sustainable alternative to rice hulls in Baijiu fermentation. The flavor profiles in jiupei and Baijiu were interpreted by employing head-space solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS), while their physicochemical characteristics were systematically assessed. Statistical evaluations, such as correlation analysis and cluster analysis, were conducted to interpret the data. The results showed that compared with rice hull, pomegranate peel reduced furfural content in jiupei by 90%, increased the alcohol distillation rate (alcohol distillation rate: this refers to the weight percentage of 50% alcohol by volume (ABV) Baijiu produced from a unit amount of raw material under standard atmospheric pressure at 20 °C (also known as Baijiu yield)) by 30%, enhanced antioxidant capacity by 24.38%, and improved starch efficiency by 3%. Notably, the Baijiu complied with the premium Baijiu standards specified in the Chinese National Standard for light-flavor Baijiu. Additionally, under the experimental conditions of this study, the optimal Baijiu yield (optimal Baijiu yield: the maximum achievable Baijiu production under defined constraints (e.g., energy input, time, cost)) (48% ± 3.41%) correlated with the pomegranate peel particle size. This research highlights the viability of using pomegranate peel as a sustainable and environmentally friendly adjunct in the fermentation of light-flavor Baijiu, offering valuable perspectives for exploring alternative brewing ingredients. Full article

The precision estimation of N fertilizer application according to the nitrogen nutrition index (NNI) using unmanned aerial vehicle (UAV) multi-spectral measurements remains to be tested in different rice cultivars and planting areas. Therefore, two field experiments were conducted using varied N rates (0, 60, 120, 160, and 200 kg N ha⁻¹) on two rice cultivars, Yunjing37 (YJ-37, Oryza sativa subsp. Japonica Kato., the Institute of Food Crops at the Yunnan Academy of Agricultural Sciences, Kunming, China) and Jiyou6135 (JY-6135, Oryza sativa subsp. indica Kato., Hunan Longping Gaoke Nongping seed industry Co., Ltd., Changsha, China), in southwest China. The rice canopy spectral images were measured by the UAV’s multi-spectral remote sensing at three growing stages. The NNI was calculated based on the critical N (Nc) dilution curve. A random forest model integrating multi-vegetation indices established the NNI inversion, facilitating precise N topdressing through a linear platform of NNI-Relative Yield and the remote sensing NNI-based N balance approaches. The Nc dilution curve calibrated with aboveground dry matter demonstrated the highest accuracy (R² = 0.93, 0.97 for shoot components in cultivars YJ-37 and JY-6135), outperforming stem (R² = 0.70, 0.76) and leaf (R² = 0.80, 0.89) based models. The RF combined with six vegetation index combinations was found to be the best predictor of NNI at each growing period (YJ-37: R² is 0.70–0.97, RMSE is 0.02~0.04; JY-6135: R² is 0.71–0.92, RMSE is 0.04~0.05). The RF surpassed BPNN/PLSR by 6.14–10.10% in R² and 13.71–33.65% in error reduction across the critical rice growth stages. The topdressing amounts of YJ-37 and JY-6135 were 111–124 kg ha⁻¹ and 80–133 kg ha⁻¹, with low errors of 2.50~8.73 kg ha⁻¹ for YJ-37 and 2.52~5.53 kg ha⁻¹ for JY-6135 in the jointing (JT) and heading (HD) stages. These results are promising for the precise topdressing of rice using a remote sensing NNI-based N balance method. The combination of UAV multi-spectral imaging with the NNI-nitrogen balance method was tested for the first time in southwest China, demonstrating its feasibility and offering a regional approach for precise rice topdressing. Full article

Premature harvesting is a prevalent concern in rice cultivation, significantly impacting both grain yield and quality. However, there is limited information regarding the specific effects of premature harvesting on rice quality, particularly in terms of taste value. Consequently, this research aimed to assess the distribution of rice maturity and its implications for rice quality. A comprehensive study was conducted, comprising a one-year survey study and two years of field experiments, to examine the effects of premature harvesting on head rice rate, taste value, amylose content, and protein content. In the survey study, the results indicated that, on average, more than one-quarter of the samples exhibited a green rice rate exceeding 10% at harvest, with the majority having rates surpassing 15%. Premature harvesting was found to significantly reduce grain weight, head rice rate, and taste value, especially when the green rice rate exceeded 15%. Similarly, research experimentation demonstrated that premature harvesting significantly decreased the head rice rate and taste value, accompanied by a reduction in amylose content and an increase in protein content. The head rice rate (r = −0.148 **, p < 0.01), taste value (r = −0.217 **, p < 0.01), amylose content (r = −0.854 **, p < 0.01), and protein content (r = 0.475 **, p < 0.01) exhibited significant correlations with the green rice rate. These findings indicated that optimizing the harvest date is crucial to achieving a low green rice rate (<15%), thereby ensuring high head rice rate, taste value, and amylose content, along with low protein content. Full article

With the continuous improvement in living standards, consumers’ demand for rice quality has been increasingly growing. This study analyzed the quality characteristics of different rice varieties under various cultivation methods. This study examined the rice variety Liaoxing 21 (LX21), the upland rice variety Han 9710 (H9710), and the hybrid rice variety Liaoyou 7362 (LY7362) from Liaoning Province to evaluate the effects of transplanting (TP) and direct seeding (DS) on processing, appearance, nutritional, and tasting quality. The results indicated that the planting method (PM) had a relatively minor impact on processing quality. Compared to TP, DS significantly increased grain length (GL) by 1.19%, grain width (GW) by 2.69%, appearance (A) by 2.61%, stickiness (Ss) by 7.15%, degree of balance (DB) by 3.19%, apparent amylose content (AAC%) by 6.20%, fa by 0.66%, fa/fb₃ by 5.34%, and protein content (PC) by 19.93%. However, DS significantly reduced the grain length/width ratio (GL/W) by 1.03%, chalky grain rate (CGR) by 46.00%, chalkiness (CH) by 52.76%, and fb₃ by 4.23%. Compared to DS, TP resulted in a higher peak viscosity (PV), final viscosity (FV), and pasting temperature (PaT), whereas setback (SB) was lower. Among the tested varieties, LX21 exhibited superior milled rice rate (MRR), head rice rate (HRR), GL, GL/W, A, Ss, DB, taste value (T), and FV compared to H9710 and LY7362, while demonstrating significantly lower CGR, CH, hardness (H), fa, trough viscosity (TV), and peak time (PeT). Under the same planting conditions, the conventional rice variety LX21 demonstrated excellent processing, appearance, and taste quality, whereas H9710 exhibited favorable nutritional quality and Rapid Visco Analyzer (RVA) characteristics. Meanwhile, we also analyzed the correlation between temperature/light conditions and nutritional quality, as well as RVA profiles. The results showed that variations in temperature and light were closely associated with amylopectin accumulation and starch pasting properties. This study highlights the findings that selecting the appropriate PMs and japonica rice varieties can effectively enhance overall rice quality. In the medium maturing regions of Liaoning Province, adopting DS with medium–early maturing japonica rice varieties offers an optimal production strategy for achieving high quality, high yield, and efficient utilization of temperature and light resources. Full article

Achieving precise seed distribution is essential for optimizing crop yields and agricultural productivity. This study examines the impact of divider head geometry on seed distribution accuracy in pneumatic air seeder systems using rapeseed, wheat, and rice. Three custom-designed divider heads—funnel distributor (A1), closed-funnel distributor (A2), and cone-shaped distributor (A3)—were developed for an eight-furrow opener seeding system, each featuring eight outlets per opener. Bench tests at air pressures of 3, 3.5, 4, 4.5, 5, and 5.5 kPa and speeds of 4 and 5 km/h revealed significant variations in seed distribution accuracy among the designs. The A2 distributor demonstrated the lowest coefficient of variation (CV) across all seed types: 4.3%, 2.6%, and 6.95% for A1, A2, and A3 in wheat, respectively; 4.5%, 3.4%, and 6.2% in rice, respectively; and 0.3%, 0.1%, and 1.0% in rapeseed, respectively. Seed types also significantly influenced feed rate uniformity, with average CVs of 2.91% for rapeseed, 3.85% for rice, and 4.90% for wheat. CFD-DEM simulations validated the superior performance of the A2 distributor by analyzing flow fields and velocity distributions, showing reductions in CVs by 19.09–54.55% compared to A1 and A3. Thus, the A2 distributor was identified as the optimal design, significantly improving seeding uniformity across all seed types. In conclusion, this study provides critical insights for redesigning seed drill distribution heads to minimize turbulence in the seed–air mixture transport, enhancing seeding uniformity and increasing crop yields and agricultural productivity. Full article

Nanjing series japonica rice varieties developed by the Institute of Food Crops, Jiangsu Academy of Agricultural Sciences in China have the characteristics of an excellent taste quality, high yield, and good resistance. They are widely promoted and applied in the lower reaches of the Yangtze River in China’s japonica rice planting areas. In response to the problem of the lack of coordination between nitrogen fertilizer management measures and variety characteristics in production, which makes it difficult to synergistically improve yield and quality, this study adopted a split-plot experimental design to study the effect of nitrogen fertilizer application on yield and rice quality of Nanjing series japonica rice varieties. In 2021, four nitrogen application rates of 0 (N₁), 150 (N₂), 300 (N₃), and 450 (N₄) kg hm⁻² (all pure nitrogen) were set up, and in 2022, four treatments of 120 (N₁), 180 (N₂), 240 (N₃), and 300 (N₄) kg hm⁻² were set up, all with nitrogen application rate as the main plot factor and variety as the sub-plot factor. The results showed that the differences between the different nitrogen fertilizer treatments were significant at the 5% or 1% level, except for the milled rice rate, head rice rate, peak viscosity, setback viscosity, and paste temperature in 2021 and panicle number, grain number per panicle, all Rapid Visco-analyzer (RVA) characteristic values, and amylose content in 2022. With an increase in the nitrogen application rate, the number of panicles, grain number per panicle, and yield increased. Either the rates of brown rice, milled rice, or head rice and chalky grains or chalkiness showed an increase trend. The peak viscosity, hot viscosity, final viscosity, and breakdown viscosity decreased, while the setback viscosity increased. For the quality of cooked rice, the hardness increased, appearance, viscosity, and balance decreased, protein content increased, and taste value decreased. The interaction between nitrogen application rate and variety was significant at p < 0.05 or p < 0.01 only for yield components, processing quality, and rice protein content in 2021 and for eating and cooking quality, appearance quality, and peak viscosity in 2022. Other traits were not significant. The comprehensive results from two years of experiments showed that, under the conditions of this experiment, a nitrogen application rate of 240–300 kg hm⁻² could improve the quality of rice in the Nanjing series varieties while maintaining a high yield. The results of this experiment have a guiding significance for the high-yield and high-quality cultivation of excellent-tasting Nanjing series japonica rice. Full article

In recent years, there has been widespread cultivation of high-quality rice along the southeast coast of China, particularly in Shanghai. However, the specific changes in the yield and quality performance of rice in the Shanghai region have not been well understood. A study conducted on 194 rice varieties in the Shanghai region from 1994 to 2023 focused on yield, growth characteristics, and quality. The findings revealed significant increases in rice yield (+16.8%) and spikelets per panicle (+45.4%) in the Shanghai region over the past 30 years, along with a decrease in amylose content (−27.9%). However, parameters such as grain filling, 1000-grain weight, plant height, panicle length, chalkiness, and gel consistency showed no significant changes over the same period. Additionally, the study found that the yield, nitrogen application amount, growth period, and head rice rate of japonica rice and indica-japonica hybrid rice were higher than those of indica rice, although the panicle length was lower in comparison. Japonica inbred rice exhibited the lowest amylose content and superior taste. Correlation analyses suggested that the breeding of japonica rice varieties in the Shanghai region should focus on balancing nitrogen absorption and high chalkiness, plant biomass, and amylose content, and yield and the appearance and taste quality of rice. In addition, the potential rice yield per unit area in the Shanghai region in the future depends on the promotion of hybrid japonica rice planting and developing best management practices. Full article

Diseases and pests have a significant impact on rice production, affecting both yield and quality. Therefore, their effective management and control are crucial for successful rice cultivation. However, current research based on rice diseases and pests (RDPs) encounters challenges such as data scarcity, the integration of multi-source heterogeneous data and usability issues related to knowledge graphs. To tackle these issues, this paper proposes a novel entity and relationship extraction model called Multi-head Attention RoBERTa BiLSTM CRF (MARBC). Specifically, the MARBC model utilizes RoBERTa to obtain related word vector representations, and then employs BiLSTM to extract features from within the input sequences. By integrating a multi-head attention mechanism, the model retrieves contextual information and relevance from the text, enhancing the accuracy and depth of the knowledge graph. Additionally, Conditional Random Fields are used to model sequence labeling for entities and relationships. Experimental results demonstrate the model’s impressive performance, achieving precision, recall, and F1 scores of 95.31%, 93.58%, and 94.44%, respectively. Furthermore, this paper constructs a dedicated knowledge graph for RDPs from both ontology and data layers. By effectively integrating and organizing multi-source heterogeneous RDP data, this paper provides valuable resources and decision support for agricultural researchers and farmers. Full article