Category Archives: ORIGINAL ARTICLE

Identification of multiple symptoms of huanglongbing by electronic nose based on the variability of volatile organic compounds

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Identification of multiple symptoms of huanglongbing by electronic nose based on the variability of volatile organic compounds

Identification of multiple symptoms of huanglongbing (HLB) by electronic nose (E-nose) based on the variability of volatile organic compounds (VOCs). (1) Headspace solid-phase microextraction gas chromatography–mass spectrometry-based analysis demonstrates the potential of E-nose for HLB detection. (2) The best feature extraction method and pattern recognition method were confirmed. (3) Optimal VOCs pick-up conditions are temp. 40°C, time 20 min, W 0.2 g, and vol 200 mL. (4) HLB can be detected based on E-nose (98.75% for HLB+, 97.50% for Zn deficiency and HLB+).


Abstract

Huanglongbing (HLB) is highly contagious and cannot be cured, resulting in a decrease in the commercial value of citrus. Timely detection and removal of diseased trees is an effective way to reduce losses. Complex symptoms of HLB, such as nutrient deficiencies often accompany HLB; as a result effective and accurate identification of HLB remains a challenge. In this study, 175 volatile organic compounds (VOCs) were detected in three categories (healthy, HLB, and Zn-deficiency) of samples using headspace solid-phase microextraction gas chromatography–mass spectrometry (HS-SPME-GC/MS), highlighting the variability of VOCs present in different categories of samples. In order to simplify the testing steps and reduce the cost in practical agricultural production, a method based on electronic nose technology to collect VOCs from citrus leaves for HLB detection was proposed. Among them, limiting value features and linear discriminant analysis were identified as the best combination of feature extraction and pattern recognition methods. Multiple sets of comparison experiments were set up and the collection conditions of VOCs were optimized. The results showed that the best classification performance was achieved for a 0.2 g sample at a collection time of 20 min when the collection temperature was 40°C and the headspace volume was 200 mL. Four types of samples (healthy, HLB-positive, Zn-deficiency, Zn-deficiency and HLB-positive) were used for model reliability validation, with an accuracy of 97.79% for HLB samples for multiple symptoms (including HLB-positive and Zn-deficiency and HLB-positive) identification. In addition, the accuracy of samples with a combined effect of Zn-deficiency and HLB was 96.43%. The results show that the E-nose-based HLB detection method is conducive to suppressing the spread of HLB, which can ensure the quality of citrus products and reduce the economic loss to horticulturists, and has good practical value.

Shedding light on a hot topic: Tuberisation in potato

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Shedding light on a hot topic: Tuberisation in potato

Schematic overview of how tuber size, tuber number and indirectly total tuber weight were affected by light and temperature, with + indicating an increasing effect on the tuber trait, and − indicating a decreasing effect. Increasing the difference in day/night temperature led to an increase in tuber size, while increasing the average temperature reduced tuber size as well as tuber number. Changes in the light spectrum affected tuber number: increasing the percentage of far-red light in the spectrum led to a higher tuber number. Also increasing the light intensity led to an increase in tuber number.


Abstract

Growing small seedling tubers from true seed, comparable with mini tubers, in controlled conditions could be a method to multiply healthy starting material of potato. In indoor farming systems, the conditions can be optimised for high production. In field trials, it is impossible to investigate the effects of environmental factors such as temperature and light separately. In this study, we performed three climate room experiments in which the effects of light intensity, temperature and percentage of far-red light in the light spectrum on tuber production were assessed. We found that increasing the average temperature reduced tuber number and tuber weight. Increasing the diurnal temperature variation while keeping the average temperature equal resulted in increased tuber size. The light treatments on the other hand only affected the number of tubers per plant: increasing light intensity and increasing the percentage of far-red light in the spectrum enhanced the number of tubers. Moreover, interaction in tuber production between inbred lines and temperature was significant, with some inbred lines being relatively tolerant to high temperature. These findings will help breed for heat tolerant varieties and optimise growing conditions for tuber production in indoor farming systems.

The post‐registration monitoring of glyphosate‐treated plants using anecic earthworms

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The post-registration monitoring of glyphosate-treated plants using anecic earthworms

Earthworm midden building activities were influenced by the use of glyphosate-based herbicides, and there were significant differences in biomass resulting from feeding earthworms in the lab with these plant materials.


Abstract

Glyphosate N-(phosphonomethyl) glycine is a widely-used herbicide in agriculture. The anecic earthworm, Lumbricus terrestris feeds and forages for surface plant materials meaning that this species has a unique and direct exposure to agrichemicals. At the recommended product rates, significantly (F1,44 = 8.67, p = .005) higher numbers of L. terrestris middens were found in the glyphosate treated areas of an arable crop field. Laboratory feeding assays using field aged plant materials indicated that previous glyphosate treatment was a statistically significant factor affecting earthworm L. terrestris biomass (F1,12 = 5.75, p = .03). Negligible glyphosate residues were detectable, and the field aged plant materials were encrusted with fungal hyphae. This suggests that glyphosate influences the colonisation of plant material by a litter-fungus complex which improves the food quality to earthworms. Concentrations of epoxiconazole, a fungicide, were detected in some plant materials and may influence overall food quality to earthworms. Glyphosate treatment on fresh volunteer plant leaves (unwanted crop seedlings) was not a statistically significant factor affecting earthworm L. terrestris biomass (F1,6 = 0.16, p = .92). These results indicate fungal communities influence feeding behaviours, and plant materials are a direct source of agrichemicals to anecic earthworms.

Heterosis and reselection for pyrethroid resistance trait maintenance in the lady beetle Eriopis connexa (Germar)

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Heterosis and reselection for pyrethroid resistance trait maintenance in the lady beetle Eriopis connexa (Germar)

Heterosis from panmictic mating resistant and susceptible Eriopis connexa phenotypes enhances offspring performance. Fecundity and survival were higher in the offspring, but higher fecundity was not sustained after reselection. Resistance maintenance in E. connexa after release will depend on insecticide exposure and selection pressure.


Abstract

Exposure of Eriopis connexa (Germar) to pyrethroid residues in agroecosystems has resulted in selection for resistance (R). Pyrethroid resistance allows E. connexa to survive lambda-cyhalothrin applications. Following a field release of E. connexa, development of resistance in an incipient population may depend on three major factors such as the maintenance of: (i) selection pressure, (ii) frequency of mating with susceptible phenotypes (S) and (iii) differential reproductive performance due to the fitness costs associated with resistance. To investigate the potential effects of these three factors on the development of pyrethroid resistance by progeny of field released E. connexa, our experiments included panmictic mating between R and S phenotypes, followed by descendant rearing with and without insecticide selection pressure, reselection and determination of resistance levels. In addition, we measured the reproductive performance of the parental R and S phenotypes and their descendants to assess the cost of resistance after crossing and reselection. Survival of R × S descendants exposed to lambda-cyhalothrin was reduced across successive generations in the absence of selection pressure, but still enhanced after four generations indicating the persistent presence of resistant phenotypes in the population. Under selection pressure with exposure to lambda-cyhalothrin applied at label rates, descendant survival was >50%. Fecundity and survival were higher in the first-generation of crossed R × S females, but higher fecundity was not sustained after reselection. Adults of the R population exhibited a fitness cost, reduced longevity, when compared to S phenotypes and R × S crossed populations. Therefore, resistance maintenance in E. connexa after release will depend on selection pressures imposed by insecticide exposure. In the absence of selection pressure, the phenotype for resistance was reduced, but not completely lost. Further, resistant phenotypes can be reselected following insecticide exposure and this can explain, in part, the high frequency of field-evolved resistance to lambda-cyhalothrin in E. connexa.

Is there a relationship between enchytraeids diversity and community with soybean (Glycine max L.) productivity in no‐till system in subtropical soils of Brazil?

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Is there a relationship between enchytraeids diversity and community with soybean (Glycine max L.) productivity in no-till system in subtropical soils of Brazil?

All genera were more abundant in high productivity than low productivity. The points with high productivity presented highest average richness. Enchytraeids demonstrating potential bioindicators of soil quality and consequently of soybean productivity in the no-tillage system for subtropical soils in Brazil.


Abstract

The relationship between the productivity of crops of agricultural interest and their interactions with physicochemical soil properties is widely explored. However, there is still a gap concerning the contribution of biological soil attributes and especially the relationship between crop productivity and the structures of organism communities within the soil, such as the enchytraeids. This paper aimed to evaluate the diversity and structures of enchytraeids communities in subtropical soils and their relationship with soybean productivity and soil properties within a no-tillage system. This study was conducted in soybean growing grounds working under no-till farming systems in southern Brazil. Samples were collected according to ISO 23611-3 and extracted with the hot–wet methodology. The organisms were identified up to their genus level. Enchytraeids density increased with the increase of soybean productivity for both evaluated crops. Enchytraeus, Fridericia, and Hemienchytraeus were more abundant in high productivity and genus Achaeta was only found in the second crop and was not a sensitive indicator toward changes in soybean productivity. Regarding the relationship between the enchytraeid community and soil attributes, the variables clay, phosphorus, moisture contents, pH, Ca/Mg as well as carbon and nitrogen from soil and litter, affected Enchytraeidae distribution. Enchytreids showed significant correlations with soybean productivity in the no-tillage system for subtropical soils in Brazil, demonstrating potential bioindicators of soil quality and consequently of soybean productivity.

Phenological growth stages of Gleditsia sinensis Lam. (Fabaceae) using the extended BBCH scale

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Phenological growth stages of Gleditsia sinensis Lam. (Fabaceae) using the extended BBCH scale

The extended BBCH (Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie) coding method to describe the morphology of the Gleditsia sinensis over two consecutive years in southwest China. Eight main growth stages were photographed, including bud development (0), leaf development (1), shoot development (3), inflorescence emergence (5), flowering (6), pod development (7), maturity of pod (8) and senescence (9). Besides, management activities were listed for each stage to allow plantation managers to better manage their trees.


Abstract

Gleditsia sinensis is a species endemic to China, an ecologically economic multipurpose tree with great development potential, which could be used as medicine, food, industrial materials and wood. It is well known that the standardized description of plant development stages according to their phenological characteristics not only is crucial for conduct of various agronomic practices, but also facilitates the exchange of new findings based on the same understanding of the plant. However, a uniform phenology scale of G. sinensis has rarely been reported, despite its expanding plant area and rapid development of this industry over the past few years. Thus, phenological events of G. sinensis were monitored based on the BBCH scale during two consecutive years in this study. Eight of the 10 BBCH stages described in detail by combining numbers and letters based on its species characteristic were accurately recorded, including bud development (0), leaf development (1), shoot development (3), inflorescence emergence (5), flowering (6), pod development (7), maturity of pod (8) and senescence (9). As far as we know, it is the first time that a special phenological rhythm for G. sinensis has been developed using an extended BBCH scale, which not only provides the basis for other basic research, but also assists growers in conducting planting management practices.

Effect of endo‐1,4‐beta‐xylanase supplementation to low‐energy diets on performance, blood constituents, nutrient digestibility, and gene expressions related growth of broiler chickens

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Abstract

The presence of soluble and insoluble non-starch polysaccharides (NSP) was reported to reduce nutrient utilisation, and adversely impact the broilers’ growth performance; accordingly, NSP-degrading enzymes are essential supplements to cereal-based diets. Therefore, the current trial was conducted to characterise the impacts of supplemental xylanase (Xyl) to diets with low-ME levels on performance, carcass traits, blood parameters, nutrient digestibility and some genes expressions in broiler chickens. A total of 600 1-day-old Ross 308 male broiler chicks were randomly assigned to 6 treatments with 10 replications of 10 birds each per group in a completely randomised design. The 6 treatments were as follow: (1) basal diets with balanced ME content served as control (positive control, PC), (2) low-energy diet (negative control 1 [NC1]; ME content reduced by 70 kcal/kg compared with PC), (3) low-energy diet (negative control 2 [NC2]; ME content reduced by 140 kcal/kg compared with PC), (4) NC1 + 100 g/ton xylanase (NC1 + 100Xyl), (5) NC2 + 100 g/ton xylanase (NC2 + 100Xyl), and (6) NC1 + 50 g/ton xylanase (NC1 + 50Xyl). At the end of the experiment (35 days of age), the reduction of energy in the NC diets yielded lower live body weight (BW) and total body weight gain (BWG) (p ˂ 0.001); however, it significantly increased feed intake (p ˂ 0.05), leading to worst feed conversion ratio (FCR) and European production efficiency factor (EPEF) (p ˂ 0.01) than PC. There was non-significant variation in final BW, BWG, FCR, or EPEF between the PC group and the NC groups supplemented with Xyl. Carcass yield, gizzard, liver and, muscle relative weights were not influenced by dietary treatments; while broilers fed diet with low-energy diets with or without Xyl addition had lower abdominal fat (p ˂ 0.01) than PC. Furthermore, broilers fed on low-ME diets supplemented with Xyl showed a reduction in plasma total cholesterol (p ˂ 0.05) and low density lipoprotein (p ˂ 0.01) levels. Greater antibody titre against Newcastle disease (p ˂ 0.05) was recorded in the NC1 + 100Xyl and NC2 + 100Xyl groups. The addition of Xyl to low-energy diets significantly improved (p ˂ 0.05) fibre digestibility compared to the PC group. Moreover, enzyme supplementation increased muscle total lipids content and decreased muscle thiobarbituric acid retroactive substance content. In addition, enzyme supplementation increased gene expression related to growth and gene expression related to fatty acid synthesis. It was concluded that a low-ME diet might diminish broiler performance, whereas Xyl supplementation to low-ME diets beneficially affected growth performance, abdominal fat percentage, nutrient digestibility and immunity for broilers, and gene expressions related to growth and fatty acid synthesis in broiler chickens fed low-energy diets.

Transition to a market economy and chronic psychosocial stress in northern Laos: An exploratory study of urinary free cortisol in rural residents

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Abstract

Objectives

The indigenous population in northern Laos has experienced a transition from self-sufficiency to a market-oriented economy, which may have brought about unprecedented chronic psychosocial stress. This study examined the association between the transition to a market economy and urinary free cortisol (UFC) concentration as a stress biomarker among rural residents of three villages with different degrees of integration into the market economy.

Methods

An interview survey and urine sample collection were conducted in August 2018 and March 2019. We measured the UFC concentration in spot urine samples collected in the morning from participants aged 20–60 years (n = 168) using an enzyme-linked immunosorbent assay. Multiple linear regression analysis was performed to examine differences in UFC concentrations among villages by sex, with time of arrival for the survey, age, and body mass index included as covariates.

Results

The UFC concentration was higher in men living in the village with the highest degree of integration into the market economy than in those in the two villages with a lower dependence on cash, possibly linking increased stress levels with a change in employment type. This trend was not observed in women.

Conclusion

Socioeconomic changes incidental to a transition to a market economy may increase the stress levels of men in northern Laos.

Safety and effectiveness of lusutrombopag in patients who have chronic liver disease with thrombocytopenia and undergoing invasive procedures: Real‐world post‐marketing surveillance in Japan

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Abstract

Aim

Lustrombopag has been approved for the treatment of thrombocytopenia in patients with chronic liver diseases who are scheduled to undergo an invasive procedure. Here, we report the final results of a post-marketing surveillance assessing the safety and effectiveness of lusutrombopag in Japan.

Methods

This multicenter, prospective, real-world surveillance collected data from case report forms between October 2016 and May 2021. The observation period was 2 months after the first day of lusutrombopag treatment. Safety and effectiveness (proportion of patients avoiding preoperative platelet transfusion and responders who achieved platelet count increase from baseline) were assessed.

Results

The safety analysis set included 1033 (100.0%), 130 (12.6%), and 14 (1.4%) patients who received one or more, two or more, and three or more treatment cycle(s), and 482 (48.9%), 457 (46.3%), and 43 (4.4%) patients who were Child–Pugh class A, B, and C, respectively. The most common serious adverse drug reactions were portal vein thrombosis, pancytopenia, and white blood cell count decrease, reported in 14 (1.36%), three (0.29%), and two (0.19%) patients, respectively. The incidence of adverse drug reactions was not higher in patients with Child–Pugh class C or those undergoing retreatment cycles compared with other Child–Pugh classes or the first treatment cycle, respectively. During the observation period of the first treatment cycle, 94.7% (889/939) of patients avoided preoperative platelet transfusion and 82.8% (741/895) of the patients met the responder criteria.

Conclusions

This surveillance study further supports the safety and effectiveness of lusutrombopag in a broad range of patients with chronic liver diseases undergoing planned invasive procedures.

Clinical Trial Registration

JapicCTI-163432.

Improvement of weanling pigs immune status and metabolic condition using ultraweak light

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Abstract

Weaning stress is the most common issue in swine farms, which increases mortality and morbidity. The use of artificial light is an option for modifying the immune system and metabolic pathways. This study aimed to evaluate the influence of ultraweak light (Photonia) on growth performance, immune system and metabolism of weanling pigs, and the carry-over effect on the growth performance in postweanling growing stages. A total of 30 weaned pigs with an average initial body weight of 7.06 ± 0.11 kg (age: 21 days) were allotted two treatments (Control and Photonia) with 15 replicates. The pelleted form diets were prepared for pigs in three phases including phase 1 (Days 0–14), phase 2 (Days 15–28) and phase 3 (Days 29–48). The gain-to-feed ratio (G:F) of pigs was significantly greater in the Photonia treatment. On Day 28, a higher concentration of immunoglobin A (IgA) (p < 0.01) and IgG (p < 0.01) was observed in the Photonia pigs. On Day 48, the Photonia treatment showed a greater serum IgA (p < 0.01) and IgG (p < 0.05). The concentration of interleukin (IL)-6 was decreased (p < 0.05) in the Photonia treatment. At Day 48, the concentrations of tumour necrotic factor-α, IL-1β and IL-6 in serum were decreased (p < 0.05) in pigs in the Photonia treatment. Metabolic pathways analysis showed that the Photonia treatment increased the d-glutamine, d-glutamate, alanine, aspartate, glutamate and phenylalanine compared with the control treatment. In conclusion, the use of Photonia for weanling pigs is recommended due to improved G:F, immune status and activation of amino acids metabolic pathways including d-glutamine, d-glutamate, alanine, aspartate, glutamate and phenylalanine.