- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Nondestructive Detection of Postharvest Quality of Cherry Tomatoes Using a Portable NIR Spectrometer and Chemometric Algorithms
摘要： The aim of this study was to assess the applicability of a portable NIR spectroscopy system and chemometric algorithms in intelligently detecting postharvest quality of cherry tomatoes. The postharvest quality of cherry tomatoes was evaluated in terms of firmness, soluble solids content (SSC), and pH, and a portable NIR spectrometer (950–1650 nm) was used to obtain the spectra of cherry tomatoes. Partial least square (PLS), support vector machine (SVM), and extreme learning machine (ELM) were applied to predict the postharvest quality of cherry tomatoes from their spectra. The effects of different preprocessing techniques, including Savitzky–Golay (S-G), multiplicative scattering correction (MSC), and standard normal variate (SNV) on prediction performance were also evaluated. Firmness, SSC and pH values of cherry tomatoes decreased during storage period, based on which the tomato samples could be classified into two distinct clusters. Similarly, cherry tomatoes with different storage time could also be separated by the NIR spectroscopic characteristics. The best prediction accuracy was obtained from ELM algorithms using the raw spectra with Rp2, RMSEP, and RPD values of 0.9666, 0.3141 N, and 5.6118 for firmness; 0.9179, 0.1485%, and 3.6249 for SSC; and 0.8519, 0.0164, and 2.7407 for pH, respectively. Excellent predictions for firmness and SSC (RPD value greater than 3.0), good prediction for pH (RPD value between 2.5 and 3.0) were obtained using ELM model. NIR spectroscopy is capable of intelligently detecting postharvest quality of cherry tomatoes during storage.
关键词： Partial least square,Extreme learning machine,Support vector machine,Cherry tomato,Near infrared spectroscopy
更新于2025-09-23 15:23:52
-
Tuning of carbon dots emission color for sensing of Fe3+ ion and bioimaging applications
摘要： Herein, we report a facile one-step synthetic strategy for fabrication of three (blue, green and yellow) fluorescent color carbon dots (CDs) from tomato (Solanum lycopersicum). The as-synthesized CDs showed emission peaks at 450, 520 and 560 nm for blue, green and yellow color CDs when excited at 370, 420 and 460 nm, respectively. Using tomato as a carbon source, the fabricated three fluorescent color CDs showed good water dispersity and high quantum yield. The analytical performances of three fluorescent color CDs are evaluated by detecting Fe3+ ion in biofluids and iron tablets. Upon the addition of Fe3+ ion under optimal conditions, the fluorescence intensity of three fluorescent color CDs was quenched linearly over the range of 0.1 to 2.0 μM. This method opens a new analytical strategy to quantify Fe3+ ion in iron tablets and biofluids with high sensitivity. Further, the uptake of three fluorescent color CDs into HeLa cells was confirmed by confocal laser scanning microscopy. Intracellular experiments demonstrated that the three fluorescent color CDs were effectively internalized the cells and show excellent biocompatibility and low toxicity, suggesting that the CDs can be used as good candidates for biomedical applications.
关键词： Fluorescent carbon dots,Fe3+ ion,Cancer cells,Fluorescence spectroscopy and microscopy,Tomato
更新于2025-09-23 15:22:29
-
Preliminary application of diffuse light film in a Chinese solar greenhouse
摘要： To explore the application of diffuse light film in a Chinese solar greenhouse (CSG), we did several comparative trials in CSGs in Beijing, Ningxia and Shandong provinces. We did three contrast tests on CSG cover films with average haze of 16.8 and 36.2%, including trials on tomatoes (in Beijing, seedlings; in Shandong, cultivation) and cucumbers (in Beijing, seedlings); the other four experiments used with films in an average haze 24.2 and 39.7%, which included trials on tomatoes (in Beijing, seedlings; in Ningxia, cultivation) and cucumbers (in Beijing, seedlings; in Ningxia, cultivation). Plant growth parameters, yield and quality index were evaluated. The result of preliminary tests showed that a higher haze film was able to improve homogeneity of light in the crop canopy and had a positive effect on cultivation. For example, in the contrast tests, we observed that a film with higher haze contributed to increases in plant height, stem diameter, leaf area, SPAD chlorophyll index, and seedling index; the seedling indices of tomatoes and cucumbers were enhanced by 50 and 10.5%, respectively, and their yields were increased by 17.0 and 21.9%, respectively, which demonstrated the outstanding impact of the higher haze films on production. Furthermore, it played a significant and positive role in flower bud differentiation of cucumbers, harvest time of tomatoes and cucumbers, and fruit quality of both crops. Based on the results of these preliminary tests, it can be concluded the diffuse film was able to accelerate plant growth and enhance crop production.
关键词： diffuse light film,Chinese solar greenhouse,tomato,cucumber
更新于2025-09-23 15:22:29
-
Metabolomic insights of the tomato fruits (Solanum lycopersicum L.) cultivated under different supplemental LED lighting and mineral nutrient conditions
摘要： Appropriate adjustment of various microclimatic and nutrient conditions can improve crop productivity under greenhouse cultivation. Here, we performed non-targeted profiling to investigate metabolite variation in tomato fruits following different supplementary LED lighting (SL) (red: R; blue: B; and a combination of red and blue light: RB, for 1 h/day and 6 h/day per condition) and mineral nutrient supply (N, K, Mg). The different SL treatments affected metabolite variation in tomato fruits more significantly than mineral nutrients. Importantly, regulating the SL period induced a more distinct metabolite composition in tomato fruits than that induced by varying the SL sources. Tomato fruits cultivated under RB for 6 h/day had a relatively higher content of sugar derivatives, especially sucrose, thus influencing the gustatory characteristics of the fruit. In contrast, fruit from tomatoes cultivated under RB for 1 h/day showed a distinctive increase in the abundance of amino acids, organic acids, and several secondary metabolites, adding to its nutritional quality. Intriguingly, the different mineral supplements elicited discriminant metabolic variation in tomato fruits cultivated under reduced levels of mineral supply; however, the effects were insignificant under enhanced levels of mineral supply. Specifically, reduced level in nitrogen supply resulted in a lower abundance of amino acids, whereas reduced level in potassium supply increased metabolite levels including amino acids, sugars, and fatty acids in tomato fruits. In the present study, we employed a non-targeted metabolomics approach to unravel the effects of microclimatic parameters and mineral nutrients on fruit quality parameters of tomato plants, by which regulating the period of SL and reducing the potassium concentration were suggested to improve different nutritional qualities.
关键词： Metabolite profiling,Supplemental lighting,Tomato fruit,Mineral nutrient,LED source
更新于2025-09-23 15:19:57
-
Quantitative Analysis of Cadmium Content in Tomato Leaves Based on Hyperspectral Image and Feature Selection
摘要： In order to ensure that safe and healthy tomatoes can be provided to people, a method for quantitative determination of cadmium content in tomato leaves based on hyperspectral imaging technology was put forward in this study. Tomato leaves with seven cadmium stress gradients were studied. Hyperspectral images of all samples were firstly acquired by the hyperspectral imaging system, then the spectral data were extracted from the hyperspectral images. To simplify the model, three algorithms of competitive adaptive reweighted sampling (CARS), variable combination population analysis (VCPA) and bootstrapping soft shrinkage (BOSS) were used to select the feature wavelengths ranging from 431 to 962 nm. Final results showed that BOSS can improve prediction performance and greatly reduce features when compared with the other two selection methods. The BOSS model got the best accuracy in calibration and prediction with R2c of 0.9907 and RMSEC of 0.4257mg/kg, R2p of 0.9821, and RMSEP of 0.6461 mg/kg. Hence, the method of hyperspectral technology combined with the BOSS feature selection is feasible for detecting the cadmium content of tomato leaves, which can potentially provide a new method and thought for cadmium content detection of other crops.
关键词： Regression model,Feature selection,Tomato leaves,Hyperspectral image technology,Non-destructive analysis
更新于2025-09-19 17:15:36
-
Alternating Red and Blue Light-Emitting Diodes Allows for Injury-Free Tomato Production With Continuous Lighting
摘要： Plant biomass is largely dictated by the total amount of light intercepted by the plant [daily light integral (DLI) — intensity × photoperiod]. Continuous light (CL, 24 h lighting) has been hypothesized to increase plant biomass and yield if CL does not cause any injury. However, lighting longer than 18 h causes leaf injury in tomato characterized by interveinal chlorosis and yield is no longer increased with further photoperiod extension in tomatoes. Our previous research indicated the response of cucumbers to long photoperiod of lighting varies with light spectrum. Therefore, we set out to examine greenhouse tomato production under supplemental CL using an alternating red (200 μmol m?2 s?1, 06:00–18:00) and blue (50 μmol m?2 s?1, 18:00–06:00) spectrum in comparison to a 12 h supplemental lighting treatment with a red/blue mixture (200 μmol m?2 s?1 red + 50 μmol m?2 s?1 blue, 06:00–18:00) at the same DLI. Our results indicate that tomato plants grown under supplemental CL using the red and blue alternating spectrum were injury-free. Furthermore, parameters related to photosynthetic performance (i.e., Pnmax, quantum yield, and Fv/Fm) were similar between CL and 12 h lighting treatments indicating no detrimental effect of growth under CL. Leaves under CL produced higher net carbon exchange rates (NCER) during the subjective night period (18:00–06:00) compared to plants grown under 12 h lighting. Notably, 53 days into the treatment, leaves grown under CL produced positive NCER values (photosynthesis) during the subjective night period, a period typically associated with respiration. At 53 days into the growth cycle, it is estimated that leaves under CL will accumulate approximately 800 mg C m?2 more than leaves under 12 h lighting over a 24 h period. Leaves grown under CL also displayed similar diurnal patterns in carbohydrates (glucose, fructose, sucrose, and starch) as leaves under 12 h lighting indicating no adverse effects on carbohydrate metabolism under CL. Taken together, this study provides evidence that red and blue spectral alternations during CL allow for injury-free tomato production. We suggest that an alternating spectrum during CL may alleviate the injury typically associated with CL production in tomato.
关键词： photoperiod,light-emitting diodes,continuous lighting,tomato,spectral quality,greenhouse,net carbon exchange rate,supplemental lighting
更新于2025-09-12 10:27:22
-
Effect of Different Combinations of Red and Blue LED Light on Growth Characteristics and Pigment Content of In Vitro Tomato Plantlets
摘要： The aim of this study was to evaluate the growth characteristics and pigment content of tomato plantlets grown under various ratios of red (R) (661 nm) and blue (B) (449 nm) LED light. In this study, three di?erent ratios of R and B (RB) light such as 5:01, 10:01, and 19:01 along with R (100%) were used. The photosynthetic photon ?ux density (PPFD), and photoperiod of the growth chamber was 120 ± 5 μmol m?2s?1 and 16/8 h (day/night), respectively. Tomato plantlets were cultured for six weeks in the growth chamber. It was shown that tomato plantlets had higher photosynthesis rate, higher pigments content, higher growth characteristics (e.g., number of leaves, leaf area, shoot number, root number, root length, dry, and fresh mass), and greater surviving rate under the R:B = 10:01 ratio among the treatments. The plantlets showed at least a threefold decrease in photosynthesis rate, as well as a signi?cant abnormal stem elongation when grown under 100% R light. It is concluded that the RB ratio of 10:01 showed excellent performance in all growth parameters. This result has shown that the optimum lighting environment improves tomato plantlet cultures in vitro.
关键词： tomato plantlets,pigments,light-emitting diode (LED),biomass,photosynthesis
更新于2025-09-12 10:27:22
-
Red/blue light ratio strongly affects steady-state photosynthesis, but hardly affects photosynthetic induction, in tomato ( <i>Solanum lycopersicum</i> )
摘要： Plants are often subjected to rapidly alternating light intensity and quality. While both short- and long-term changes in red and blue light affect leaf photosynthesis, their impact on dynamic photosynthesis is not well documented. It was tested how dynamic and steady-state photosynthetic traits were affected by red/blue ratios, either during growth or during measurements, in tomato leaves. Four red/blue ratios were used: monochromatic red (R100), monochromatic blue (B100), a red/blue light ratio of 9:1 (R90B10) and a red/blue light ratio of 7:3 (R70B30). R100 grown leaves showed decreased photosynthetic capacity (maximum rates of light-saturated photosynthesis, carboxylation, electron transport and triose phosphate use), leaf thickness and nitrogen concentrations. Acclimation to various red/blue ratios had limited effects on photosynthetic induction in dark-adapted leaves. B100 grown leaves had a ~15% larger initial NPQ transient than the other treatments, which may be beneficial for photoprotection under fluctuating light. B100 grown leaves also showed faster stomatal closure when exposed to low light intensity, which likely resulted from smaller stomata and higher stomatal density. When measured under different red/blue ratios, stomatal opening rate and photosynthetic induction rate were hardly accelerated by increased fractions of blue light in both growth chamber-grown leaves and greenhouse-grown leaves. However, steady-state photosynthesis rate 30 min after photosynthetic induction was strongly reduced in leaves exposed to B100 during the measurement. We conclude that varying red/blue light ratios during growth and measurement strongly affects steady-state photosynthesis, but has limited effects on photosynthetic induction rate.
关键词： Solanum lycopersicum,red/blue light ratio,photosynthesis,photosynthetic induction,steady-state photosynthesis,tomato
更新于2025-09-10 09:29:36
-
Tomato Peeling Performance under Pilot Scale Catalytic Infrared Heating
摘要： Steam and lye peeling methods have been the most commercialized methods in tomatoes industry. However, they are water and energy intensive and have adverse effects on the environment. The infrared (IR) dry-peeling was studied as a sustainable tomato peeling method because it does not require water nor chemicals. An IR peeling system equipped with catalytic IR emitters was designed and constructed. The peeling performance of the system, in terms of peelability, peeling loss, and product quality, was examined under different loading rates using the tomatoes cultivars, Hz 5608, Seminis DRI 319, and Seminis HP 849. Peeling performance was significantly (α = 0.05) affected by surface temperature of tomatoes during IR heating. A tomato surface temperature range of 109 - 115°C (±2°C) during IR heating was found to be optimum for achieving a good peeling performance. Compared to conventional lye peeling, IR dry-peeling produced up to 38.2% firmer peeled tomatoes and up to 12.2% lower peeling loss with a similar or better peeling easiness and more desirable color of the peeled tomatoes.
关键词： Tomato,Peelability,Sustainable processing,Infrared heating,Lye peeling
更新于2025-09-10 09:29:36
-
[American Society of Agricultural and Biological Engineers 2018 Detroit, Michigan July 29 - August 1, 2018 - ()] 2018 Detroit, Michigan July 29 - August 1, 2018 - Classification of Tomato Impact Bruise Using Hyperspectral Imaging Based on Spatial-spectral Method
摘要： Tomatoes have various drop impacts on post-harvest process, which causes the quality deterioration. It is required to evaluate impact injuries quickly in a non-destructive method. Hyperspectral image is commonly of with multi-modal classes and ambiguous class boundary, and spatially adaptive classification of land cover with hyperspectral image is one of challenging problems in accurate classification image community. As hyperspectral image includes many interesting objects whereas each object contains variant spectral signature and the discrimination among them is less efficient. This paper presents a new spatial-spectral fusion method, which extracts patch analysis and combines spectral features to perform fruit quality classification. In spectral features, a method of tomato quality classification based on mean-square-error curve fitting and peak-feature matching is presented. It extracts peak features from known drop injury tomatoes’ spectra and unknown tomato samples spectra to compute their similarity values through multiple similarity measures, respectively. Then, the unknown sample is assigned by selecting the known quality tomato with the largest similarity value. At last, in comparison with the proposed method and the method such as partial-least square discriminate analysis (PLS-DA), support vector machine (SVM), the result shows the practicality and accuracy of the proposed method.
关键词： Tomato,Quality Classification,Peak-feature matching,Patch Analysis,Hyperspectral Image
更新于2025-09-09 09:28:46