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The pollution caused by plastic mulch film in agriculture has garnered significant attention. To safeguard the ecosystem from the detrimental effects of plastic pollution, it is imperative to investigate the use of biodegradable materials for manufacturing agricultural plastic film. Biochar has emerged as a feasible substance for the production of biodegradable mulch film (BDM), providing significant agricultural soil benefits. Although biochar has been widely applied in BDM manufacturing, the effect of biochar-filled plastic mulch film on soil carbon stock after its degradation has not been well documented. This study provides an overview of the current stage of biochar incorporated with BDM and summarizes its possible pathway on soil carbon stock contribution. The application of biochar-incorporated BDM can lead to substantial changes in soil microbial diversity, thereby influencing the emissions of greenhouse gases. These alterations may ultimately yield unforeseen repercussions on the carbon cycles. However, in light of the current knowledge vacuum and potential challenges, additional study is necessary to ascertain if biochar-incorporated BDM can effectively mitigate the issues of residual mulch film and microplastic contamination in agricultural land. Significant progress remains necessary before BDM may fully supplant traditional agricultural mulch film in agricultural production.

Exploring the development and impacts of drought across different ecosystems can offer new insights for mitigating the adverse effects of drought events. Using the pantropical Lancang-Mekong River Basin as the study region, we investigated the agricultural, ecological, and hydrological drought characteristics and explored their drought progression and recession rates across four vegetation ecosystem types: tropical forests, subtropical forests, shrubs, and crops. We utilized newly developed drought indices based on the ERA5-Land reanalysis dataset, GOSIF chlorophyll fluorescence data, and modified Moderate Resolution Imaging Spectroradiometer (MODIS) land cover data. The results showed that agricultural and hydrological droughts exhibited increasing trends from 2001 to 2021, whereas ecological drought displayed a decreasing trend over the same period. The cropland region experienced the fewest drought events, shortest drought durations, slowest progression rates, and lowest recession rates. By contrast, the two evergreen, broadleaf forest ecosystems (subtropical and tropical forests) experienced the highest number of drought events and fastest progression and recession rates. The findings suggest a trade-off relationship between vegetation resistance and recovery, where faster drought onset is associated with faster drought recession for ecological drought. Given the more severe challenges posed by agricultural and hydrological droughts, the riparian countries in the Lancang-Mekong River Basin should adopt proactive financial and management measures to mitigate the adverse impacts of these drought types. The insights gained from this study can inform the development of targeted strategies for drought monitoring, preparedness, and response across diverse ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Tomato, a fruit with a high vitamin content, is popular for consumption and economically important in Thailand. However, in the past year, the extensive usage of chemicals has significantly decreased tomato yields. Plant Growth-Promoting Rhizobacteria (PGPR) is an alternative that can help improve tomato production system growth and yield quality while using fewer chemicals. The present study aimed to determine whether endophytic actinomycetes promote growth and fruit quality of tomato ( Solanum lycopersicum )., Methods: The experiment was conducted in a net-houses at the Center for Agricultural Resource System Research, Faculty of Agriculture, Chiang Mai University, Chiang Mai province, Thailand. The randomized completely block design (RCBD) was carried out for four treatments with three replications, which was control, inoculation with TGsR-03-04, TGsL-02-05 and TGsR-03-04 with TGsL-02-05 in tomato plant. Isolated Actinomycetes spp. of each treatment was then inoculated into the root zone of tomato seedlings and analyzed by Scanning Electron Microscopy (SEM). The height of tomato plants was measured at 14, 28, 56, and 112 days after transplanting. Final yield and yield quality of tomato was assessed at the maturity phase., Results: The SEM result illustrated that the roots of tomato seedlings from all treatments were colonized by endophytic actinomycetes species. This contributed to a significant increase in plant height at 14 days after transplanting (DAT), as found in the TGsR-03-04 treatment (19.40 cm) compared to the control. Besides, all inoculated treatments enhanced tomato yield and yield quality. The highest weight per fruit (47.38 g), fruit length (52.37 mm), vitamin C content (23.30 mg 100 g -1 ), and lycopene content (145.92 µg g -1 ) were obtained by inoculation with TGsR-03-04. Moreover, the highest yield (1.47 kg plant -1 ) was obtained by inoculation with TGsL-02-05. There was no statistically significant difference in the number of fruits per plant, fruit width, brix, and antioxidant activity when various inoculations of endophytic actinomycetes were applied. Therefore, the use of endophytic actinomycetes in tomato cultivation may be an alternative to increase tomato yield and yield quality., Competing Interests: The authors declare there are no competing interests., (©2024 Khomampai et al.)

The analysis of soil organic matter (OM), total carbon (TC), and total nitrogen (TN) using traditional methods is quite time-consuming and involves the use of hazardous chemical reagents. Absorbance spectroscopy, especially near-infrared (NIR), is becoming more popular for soil analysis. This method requires little sample preparation, no chemicals, and a single spectral analysis to evaluate soil properties. Thus, this research aimed to develop an NIR spectroscopy method for the analysis of OM, TC, and TN in agricultural soils. These findings can provide a good concept of using PLS regression with NIR techniques. The method is as follows:•Topsoil (0-20 cm) samples were collected from various agricultural fields. OM, TC, and TN were analyzed using traditional methods and NIR spectroscopy.•NIR spectra were obtained using an FT-NIR spectrometer, original spectral including with Savitzky-Golay smoothing, standard normal variate (SNV) and multiplicative scatter correction (MSC) preprocessing method were used to create a predicted model through Partial Least Squares (PLS) regression with 65 % calibration, and the rest 35 % for validation.•The results showed significant relationships between measured soil properties (SOM and TC) and NIR absorbance spectra in agricultural soil ( R 2 of calibration and validation higher than 0.80)., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Background: Greenhouse vertical farming under natural sunlight is an alternative farming technique that grows crops in a stacking column and extends in a vertical direction. Sunlight availability is one of the crucial factors for crop development in vertical farming. Therefore, this investigation aimed to examine the effect of sunlight availability on lettuce growth and yields at different levels of vertical shelves., Methods: Six shelves were constructed with three levels: upper, middle and lower levels. Lettuces ( Lactuca sativa L.) as 'Baby Cos' and 'Green Oak' at 14 days after sowing were planted on the three levels. The photosynthetic photon flux density (PPFD) was recorded, and the PPFD values were then converted to the daily light integral (DLI). Plant height and canopy width were measured three times at 14, 21 and 28 days after transplanting. At maturity, fresh weight (FW) was directly monitored after harvest., Results: The results showed that the highest PPFD and DLI values were found at the upper level (PPFD 697 μmol m -2 s -1 and DLI 29 mol m -2 d -1 ) in comparison to the middle (PPFD 391 μmol m -2 s -1 and DLI 16 mol m -2 d -1 ) and lower (PPFD 322 μmol m -2 s -1 and DLI 13 mol m -2 d -1 ) levels. The lowest plant height and canopy width values were observed on the upper levels for both lettuce varieties during the three measurement dates. The middle ('Baby Cos' = 123.8 g plant -1 and 'Green Oak' = 190.7 g plant -1 ) and lower ('Baby Cos' = 92.9 g plant -1 and 'Green Oak' = 203.7 g plant -1 ) levels had the higher values of FW in comparison to the upper level ('Baby Cos' = 84.5 g plant -1 and 'Green Oak' = 97.3 g plant -1 ). The values of light use efficiency (LUE) showed an increased trend from the upper to lower levels in both varieties, with values of 'Baby Cos' of 0.10 g mol -1 in the upper level, 0.28 g mol -1 in the middle level and 0.26 g mol -1 in the lower level and 'Green Oak' of 0.12 g mol -1 in the upper level, 0.44 g mol -1 in the middle level and 0.57 g mol -1 in the lower level. The findings of the study indicated the viability of utilizing vertical shelves for lettuce production., Competing Interests: The authors declare that they have no competing interests., (© 2024 Wicharuck et al.)

The utilization of a non-destructive SPAD-502 chlorophyll meter, which enables the measurement of nitrogen status in plant leaves, has gained popularity in agronomic crops. Its application to horticultural crops like coffee remains relatively uncommon. The device provides quick and real-time measurements, helping to provide on-time nitrogen fertilizer to coffee plants before deficiency signs occur. Coffee leaves are characterized by thick and waxy leaves, together with many layers of tree crown. Therefore, the objective of this study was to develop a method for measuring nitrogen levels in coffee plants using the SPAD-502 Chlorophyll meter for an appropriate nitrogen fertilizer application rate in Arabica coffee plants. •Coffee trees were separated into upper, middle and lower levels. Data on SPAD values and total nitrogen were analyzed.•Pearson Correlation Coefficient (R), Coefficient of Determination (R 2 ) and linear regression were calculated for different three levels of both SPAD-502 and total nitrogen values.•The results revealed a strong correlation (R 2  = 0.63) between the SPAD readings of coffee leaves obtained from the upper canopy and their nitrogen content. These findings can provide a good concept of which coffee crown level will be a better part for measuring N content using a SPAD-502 Chlorophyll meter., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

Land conversion critically affects soil physiochemical and biological properties, yet very little remains clear about the impact of forest conversion on the N pool and related microbial N transformations. Therefore, this study aimed to examine the dynamics of soil N availability following forest conversion into the different coffee cropping systems, and explore the mechanisms behind these dynamics from the microbial N transformation. Disturbed soil samples from two depths (0-20 and 20-40 cm) were collected from four land uses consisting of three different coffee cropping systems (coffee monocultures (C), coffee agroforestry (FC), coffee associated with persimmon ( Diospyros kaki L.) (CH)) converted from natural forest and adjacent natural forest (F) in northern Thailand. The soil labile N pools (including ammonium (NH 4 + ), inorganic N (IN), dissolved organic N (DON) contents and microbial biomass N (MBN)) were measured, as well as the soil total N (STN) content. Soil N transformation rates, including net N mineralization, nitrification, and immobilization, were determined using a laboratory incubation experiment. The results showed that the forest conversion to coffee agroforestry significantly increased soil N content by 39.83 % in topsoil, but no significant difference was observed in C and CH soils as compared to F soil (p ≤ 0.05). The three labile N forms (NH 3 - ), inorganic N (IN), dissolved organic N (DON) contents and microbial biomass N (MBN)) were measured, as well as the soil total N (STN) content. Soil N transformation rates, including net N mineralization, nitrification, and immobilization, were determined using a laboratory incubation experiment. The results showed that the forest conversion to coffee agroforestry significantly increased soil N content by 39.83 % in topsoil, but no significant difference was observed in C and CH soils as compared to F soil (p ≤ 0.05). The three labile N forms (NH 4 + ratios used as an N availability indicator were positively associated with an increase in the N mineralization and nitrification processes following the forest conversion. Interestingly, the N immobilization processes in the F and FC soils were significantly higher than those in the C and CH soils, which indirectly regulated a decreased nitrification rate in F and FC soils in our study. With the exception of the FC soil, the nitrification/N immobilization ratios in the C (4.95) and CH (4.08) soils were higher than those in the F (0.70) soil, indicating an increased N loss risk after forest conversion. Therefore, coffee agroforestry systems have the potential to be effective management strategies for improving soil nitrogen sequestration following forest conversion.3 - and DON content) were significantly higher under the C, FC and CH soils in both depths, while the coffee monoculture decreased the MBN content. The increases in soil IN, IN/DON and NO 3 - /NH 4 + ratios used as an N availability indicator were positively associated with an increase in the N mineralization and nitrification processes following the forest conversion. Interestingly, the N immobilization processes in the F and FC soils were significantly higher than those in the C and CH soils, which indirectly regulated a decreased nitrification rate in F and FC soils in our study. With the exception of the FC soil, the nitrification/N immobilization ratios in the C (4.95) and CH (4.08) soils were higher than those in the F (0.70) soil, indicating an increased N loss risk after forest conversion. Therefore, coffee agroforestry systems have the potential to be effective management strategies for improving soil nitrogen sequestration following forest conversion., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 Chiang Mai University.)

Background: As a method for sustainable agriculture, biofertilizers containing plant growth-promoting bacteria (PGPB) have been recommended as an alternative to chemical fertilizers. However, the short shelf-life of inoculants remains a limiting factor in the development of biofertilizer technology. The present study aimed to (i) evaluate the effectiveness of four different carriers (perlite, vermiculite, diatomite and coconut coir dust) on the shelf-life of S2-4a1 and R2-3b1 isolates over 60 days after inoculation and (ii) evaluate isolated bacteria as growth-promoting agents for coffee seedlings., Methods: The rhizosphere soil-isolated S2-4a1 and plant-tissue-isolated R2-3b1 were chosen based on their P and K-solubilizing capacities and their ability to produce IAA. To evaluate the alternative carriers, two selected isolates were inoculated with the four different carriers and incubated at 25 °C for 60 days. The bacterial survival, pH, and EC in each carrier were investigated. In addition, coconut coir dust inoculated with the selected isolates was applied to the soil in pots planted with coffee ( Coffea arabica ). At 90 days following application, variables such as biomass and total N, P, K, Ca, and Mg uptakes of coffee seedlings were examined., Results: The results showed that after 60 days of inoculation at 25 °C, the population of S2-4a1 and R2-3b1 in coconut coir dust carriers was 1.3 and 2.15 × 10 8 CFU g -1 , respectively. However, there were no significant differences among carriers ( P > 0.05). The results of the present study suggested that coconut coir dust can be used as an alternative carrier for S2-4a1 and R2-3b1 isolates. The significant differences in pH and EC were observed by different carriers ( P < 0.01) after inoculation with both bacterial isolates. However, pH and EC declined significantly only with coconut coir dust during the incubation period. In addition, coconut coir dust-based bioformulations of both S2-4a1 and R2-3b1 enhanced plant growth and nutrient uptake (P, K, Ca, Mg), providing evidence that isolated bacteria possess additional growth-promoting properties., Competing Interests: The authors declare there are no competing interests., (©2023 Chromkaew et al.)

This study investigated the effects of dietary supplementation with anthocyanin extracted from black rice bran (AR) on the growth rate, immunological response, and expression of immune and antioxidant genes in Nile tilapia raised in an indoor biofloc system. A total of 300 Nile tilapia fingerlings (15.14 ± 0.032 g) were maintained in 150 L tanks and acclimatized for two weeks. Five experimental AR diets (0, 1, 2, 4, and 8 g kg -1 ) with various anthocyanin doses were used to feed the fish. We observed that the growth and feed utilization of fish fed with different dietary AR levels increased significantly after eight weeks (p < 0.05). In addition, the serum immunity of fish fed AR diets was much greater than that of those fed non-AR diets (p < 0.05). However, there were little or no difference in between fish fed AR enriched diets and the control AR-free diet (p > 0.05). After eight weeks, fish fed AR-supplemented diets had significantly higher mRNA transcript levels in immune (interleukin [IL]-1, IL-8, and liposaccharide-binding protein [LBP]) and antioxidant (glutathione transferase-alpha [GST-α] and glutathione reductase [GSR]) genes compared to control fish fed the AR-free diet, with the greatest enhancement of mRNA transcript levels (in the case of IL-8 by up to about 5.8-fold) in the 4 g kg -1  AR diet. These findings suggest that dietary inclusion of AR extract from black rice bran at 4-8 g kg -1 could function as a herbal immunostimulant to enhance growth performance, feed consumption, and immunity in Nile tilapia., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)