In this study, lambda-cyhalothrin (LC) loaded polyurea microcapsules (MCs) with different particle sizes were fabricated.  All of the MCs showed varying degrees of physical collapse, which was more obvious among those with smaller particle sizes.  MCs with particle sizes of 1.38 μm (MC-S), 5.13 μm (MC-M) and 10.05 μm (MC-L) had shell thicknesses of 39.6, 50.3 and 150.1 nm, respectively.  MCs with smaller particles tended to have significantly faster release profiles, and the MC-S group had much higher bioactivity against Agrotis ipsilon and better foliar affinity on the peanut leaves (indicated by rainfastness) than MC-M and MC-L.  All of the MCs exhibited light-enhanced release profiles and had much slower degradation compared with the emulsifiable concentrate (EC) group, among which MC-L had the slowest degradation.  To generate MCs with both favorable quick efficacy and long-lasting efficacy, binary mixtures of MC-S, MC-M and MC-L were produced by mixing them in pairs at ratios of 2:1, 1:1 and 1:2.  The mixture of MC-S:MC-L at 1:2 showed the best comprehensive efficacy in the peanut foliar spray scenario among the nine tested combinations, and its effective duration was three times longer than that of EC.  Overall, the precise combination of MCs with different particle sizes can regulate the efficacy of pesticide control and serve as a strategy for the better utilization of pesticides.

The study aimed to evaluate the application of silage fermentation in storing vine tea residue.  Dynamic of fermentation-related product, chemical component and bacterial community of silage with or without Lactobacillus plantarum F1 inoculant were analyzed.  The results showed that F1 treatment had a significant (P<0.05) impact on the lactic acid and ammoniacal nitrogen concentrations and pH value.  Total phenols were well preserved in both treatments.  After 30 days of ensiling, L. plantarum occupied the majority of Lactobacillus genus (more than 95%) in all silage samples.  Spearman revealed a positive (P<0.01) correlation between lactic acid content and Lactobacillus.  Overall, ensiling vine tea residue with L. plantarum can effectively preserve the nutritional attributes and total phenols, which offers a new insight into utilizing vine tea residue.

The efficacies of biological and conventional chemical insecticides against two major insect pests of alfalfa (aphids and thrips) were compared in three sites across China’s alfalfa belt.  In addition, the persistence of the residues of chemical insecticides in alfalfa and their influence on the quality of alfalfa hay were examined.  Efficacy varied among the different biological and chemical insecticides.  The chemical insecticides were significantly more effective than biopesticides in a short time-frame.  The efficacy period of biopesticides was significantly longer than that of chemical insecticides, and the corrected mortality rate of aphids in all regions was above 50% at 14 days after application.  The analysis of pesticide residues showed that the residual doses of all the pesticides were within the allowed ranges after the safe period.  The acid detergent fiber and neutral detergent fiber contents in alfalfa hay were higher and the protein content was lower in chemical insecticide treatments than in biopesticide treatments in Hebei.  The relative feeding value of alfalfa hay treated with Metarhizium anisopliae IPP330189 was the highest among the treatments.  Compared with chemical insecticides, the yield of alfalfa hay was higher in the biopesticides treatments.  Biopesticides show a stronger control effect on insect populations and also a better improvement in the quality of alfalfa hay than chemical insecticides.  This study provides a basis for exploring and developing a comprehensive control regime for alfalfa insect pests in the different alfalfa-growing regions in China, and for reducing chemical insecticide usage and improving forage quality.

The present study modified potato protein and flour with tyrosinase to promote the diversification of potato staple foods.  The results indicated that tyrosinase treatment markedly altered the secondary structure of proteins.  After tyrosinase treatment, the maximum decomposition temperature of potato protein and flour increased from 322.32 to 332.40°C and from 294.24 to 299.61°C, respectively.  Tyrosinase treatment remarkably reduced the pasting viscosity of potato flour, that is, the peak viscosity, through reducing viscosity, breakdown, final viscosity, and setback by 32.50, 60.98, 13.04, 68.24, and 74.31%, respectively.  In contrast, tyrosinase treatment increased the shear resistance and hardness of the protein and flour gels; the maximum stress values of the protein and flour gels increased from 1.48 to 10.1% and from 6.87 to 14.8%, respectively.  Furthermore, tyrosinase treatment promoted viscoelastic properties and structural stability of potato protein and flour.  These results may provide an important foundation for the development of novel potato staple foods.

Somatic embryogenesis (SE) is an effective approach of in vitro regeneration that depends on plant cell totipotency. However, largely unknown of molecular mechanisms of SE in woody plants such as Chinese chestnut (Castanea mollissima Blume), limits the development of the woody plant industry. Here, we report the MADS-box transcription factor CmAGL11 in Chinese chestnut. CmAGL11 transcripts specifically accumulated in the globular embryo. Overexpression of CmAGL11 in chestnut callus enhanced its SE capacity, and the development of somatic embryos occurred significantly faster than in the control. RNA-seq results showed that CmAGL11 affects the expression of several genes related to the gibberellin, auxin, and ethylene pathways. Moreover, the analysis of DNA methylation status indicated that the promoter methylation plays a role in regulation of CmAGL11 expression during SE. Our results demonstrated that CmAGL11 plays an important role in the SE process in Chinese chestnut, possibly by regulating gibberellin, auxin, and ethylene pathways. It will help establish an efficient platform to accelerate genetic improvement and germplasm innovation in Chinese chestnut.

Having an estimated production of 388 million tons in 2017 (FAO 2019), potato is one of the world’s most important food crops, along with rice, wheat, and maize.  Potato plants can adapt to different agricultural environments and are widely grown over many latitudes and elevations (Douches et al. 2004).  In addition to its consumption in Europe, North America and countries of the former Soviet Union, potato is now also popularized in Africa and Asia, especially in the developing countries including China and India.  Since 2015, China has been boosting potato production to become the fourth major crop produced in the country following rice, wheat and maize (Zhang et al. 2017; Xu et al. 2019).  And developing potato as the staple food was also included by Ministry of Agriculture and Rural Affairs of China in its important agenda.  Further improvement of potato production globally could promote the sustainable development of agriculture and safeguard world’s food security in the near future.
Insect pests are one of the major constraints to commercial production of potato in the world.  For over
8 000 years since its domestication in the central Andes, the potato has been plagued by a number of serious insect pests (Radcliffe 1982).  These include some of the most prolific and adaptable species known to human.  If left uncontrolled, the insect pests can completely destroy the affected crops.  With the rapid development of international trade, many insect herbivores of crops have spread across the continents along with agricultural products, and soon outbroke and became serious pests in their colonized areas (Carrillo et al. 2019).  To deal with the potato insect pest problems, currently several issues remain to be solved: (1) Know these insect pests.  A deep decoding of the biology and ecology of the potato insect pests is the basis for developing counter-measures to them.  (2) Know how the insects come and where they will go.  Figuring out the spreading of the invasive insects of potato can help achieve a better prevention and slow down their damage risks.  (3) Know their helpers during the harm to crops.  The co-occurrence of insects and plant pathogens in potato fields requires the raveling of how they interacts.  (4) Know the integrative management strategies.  Insect management in commercial potato production is heavily reliant on synthetic backlash and causing environmental pollution, and thus new strategies are needed to achieve a more ecological control of these pests. 
As guest editors, we are pleased to present 12 papers about the biology, ecology and management of major insect pests damaging on the potato crop in this special focus of the Journal of Integrative Agriculture.  We hope to improve our understanding of insect pests of potato and provide guidance for countries facing the IPM of those pests worldwide.  The 12 papers are organized into the following four sections.
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It is generally known that the culture for mycoplasma is time-consuming and a variety of nutrients are needed in the culture medium.  This brings a lot of difficulties to mycoplasma research and application, including Mycoplasma mycoides subsp. capri (Mmc).  Furthermore, little research on the characteristics of Mmc metabolism has been reported.  In this study, Mmc PG3 strain cultures were investigated for dynamic gene expression.  Culture samples were harvested during logarithmic phase (PG3-1), stationary phase (PG3-2), decline phase (PG3-3) and late decline phase (PG3-4).  Twelve RNA samples (three replicates for each of the four growth stages considered) from these cultures were collected and sequenced.  Paired comparison between consecutive growth phases in the four growth stages showed 45 significant differentially expressed genes (P<0.01) were linked to PG3 metabolism.  The enzymes these genes coded were mainly involved in ATP synthase, pyrimidine metabolism, nicotinate and nicotinamide metabolism, arginine and proline metabolism.  Among these, cytidylate kinase, fructose 1,6-bisphosphate aldolases Class II, nicotinate-nucleotide adenylyltransferase and dihydrolipoamide dehydrogenase play a key role in Mmc metabolism.  These results provide a baseline to build our understanding of the metabolic pathway of Mmc.  

The potato tuberworm Phthorimaea operculella Zeller, is one of the most important potato pests worldwide including China.  Several reports indicate that P. operculella could be controlled biologically by the use of beneficial fungus such as Beauveria bassiana (Bals.-Criv) Vuill.  However, limited information is available under growing conditions in China.  Thus, this study evaluated the sub-lethal effects of B. bassiana on the offspring of P. operculella by the age-stage, two-sex life table.  First instar larva of P. operculella were treated with 1×10⁷ conidia mL–1 of the fungus, and several biological parameters were evaluated.  The fecundity, duration of the egg stage, all larval stages, pre-adult stage, and total pre-oviposition period, were significantly shorter than the control treatment.  Offspring of treated parents, presented a net reproductive rate and mean generation time of 17.43 per day and 24.98 days, respectively, compared to 65.79 per day and 26.51 days for the untreated ones.  This study provides basic information to help understanding the potential long-term effects of entomopathogenic fungi on P. operculella.

    The western flower thrips, Frankliniella occidentalis, is one of the most destructive sucking pests of vegetables, fruits and ornamental crops in China. Spinosad is one of the most commonly used insecticides to manage thrips. To assess the incidence of spinosad resistance in F. occidentalis field populations in eastern China, survival rates for 24 different populations were compared with those of a susceptible laboratory strain. All populations showed significantly higher resistance to spinosad compared with the control as determined by comparing median lethal concentrations. Two populations from Shouguang and Liaocheng in Shandong Province were classified as having moderate and high levels of resistance to spinosad with a mean resistance ratio of 17.0 and 89.2, respectively. Our research indicates a widespread reduction in spinosad efficacy for controlling F. occidentalis field populations, and that resistance management strategies should be implemented as soon as practicable, to reduce the potential of progressive resistance development and loss of efficacy.

Infectious bursal disease virus (IBDV) is responsible for the highly contagious infectious bursal disease of chickens. Further understanding the gene-function is necessary to design the tailored vaccine. The amino acid residue 279, located on strand PF of VP2, is one of the three residues that have been reported to be involved in cell-tropism but with some inconsistency. In this study, to further clarify the amino acids involved in the cell tropism of IBDV, a series of mutations about residue 279 were introduced into the VP2 of vvIBDV Gx strain. With the reverse genetic system, we found single mutation of D279N, double mutations of D279N/A284T or Q253H/D279N were not enough to adapt IBDV to chicken embryo fibroblast (CEF) cell. To evaluate whether residue 279 could influence the replication and virulence of IBDV, the virus rGxHT-279 with three mutations (Q253H/D279N/A284T) was rescued and evaluated. Results showed that the mutation of residue 279 in VP2 had no efficient effects on both the replication efficiency in vitro and the virulence to SPF chickens of IBDV. In summary, the results demonstrated that residue 279 of VP2 did not contribute efficiently to cell tropism, replication efficiency, and virulence of IBDV at least in some strains. These findings provided further information for understanding the gene function of IBDV.

The entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin and predatory mite Neoseiulus barkeri Hughes are effective biological control agents of Frankliniella occidentalis Pergande (Thysanoptera: Thripidae), one of the most important pests of ornamentals and vegetables world-wide. Combined application of both may enhance control efficiency. The functional response for N. barkeri on the first instar larvae of western flower thrips which were infected by B. bassiana for 12 and 24 h in the laboratory ((25±1)°C, (70±5)% RH, L:D=16 h:8 h) was determined. The virulence of B. bassiana against the second instar and pupae of the thrips attacked by N. barkeri were also tested. The results showed that N. barkeri exhibited a Holling type II functional response on treated thrips. After having been treated with the fungus for 12 h and then offered to the predator, thrips were more vulnerable to be killed by N. barkeri. The second instar larvae and pupae of the thrips which had been attacked by predatory mites were markedly more susceptible to B. bassiana infection than normal thrips; the cumulative corrected mortality of B. bassiana of the second instar and pupae which were attacked by N. barkeri were 57 and 94%, respectively, compared to 35 and 80% in controls on the day 8. These findings highlight the potential use of B. bassiana in combination with N. barkeri to control F. occidentalis.

This study investigated effects of dietary fibre and grit on growth performance, gastrointestinal tract (GIT) development, serum indexes and grit retention of Sichuan white goslings in China. The experiment was a 3×2 factorial design consisting of dietary crude fibre (CF) at 2.0, 4.0 and 6.0% levels by adding grass meal and with or without grit supplementation. A total of 720 1-d-old male goslings were randomly allocated into 36 pens of 20 goslings/pen (n=6 pens/treatment). At 21 d of age, GIT, blood samples and grit in gizzards were collected. Body weight (BW), empty BW (without GIT), average daily gain (ADG) and average daily feed intake (ADFI) were affected by CF levels and the medium (4.0%) had the highest value. Adding grit improved BW, empty BW, ADG and ADFI. CF affected relative weight or length of proventriculus, gizzard and duodenum. Increasing CF levels decreased jejunum villus height and affected caecal crypt depth and villus height to crypt depth ratio. Higher CF levels decreased serum triglyceride. Adding grit increased relative weight of abdominal fat. Grit addition increased grit weight in gizzard and the ratio of grit in 0.45-1 and 1-2 mm while decreasing the ratio of grit <0.45 and 2-3 mm. In conclusion, moderate CF level and grit addition increased performance of goslings without interaction. Dietary CF levels affected the development of upper GIT and serum triglyceride. Grit needed by goslings should be less than 2 mm. Goslings’ gizzard would accumulate grit from feed when other grit could not be acquired.

Thrips are among the most important agricultural pests globally because of the damage inflicted by their oviposition,feeding, and ability to transmit plant viruses. Because of their invasiveness, a number of pest species are common to both China and the United States and present significant challenges to growers of a wide range of crops in both countries. Among the pest thrips common to both countries are four of the major global thrips pests, Frankliniella occidentalis (Pergande), Scirtothrips dorsalis Hood, Thrips palmi Karny, and Thrips tabaci Lindeman. This review addresses characteristics that enable thrips to be such damaging pests and how biological attributes of thrips create challenges for their management. Despite these challenges, a number of successful management tactics have been developed for various cropping systems. We discuss some of these tactics that have been developed,including the use of cultural controls, biological controls, and judicious use of insecticides that do not disrupt overall pest management programs. The exchange of this type of information will help to facilitate management of pest thrips, especially in regions where species have recently invaded. A prime example is F. occidentalis, the western flower thrips, which is native to the United States, but has recently invaded China. Therefore, management tactics developed in the United States can be adapted to China. Because further success in management of thrips requires a thorough understanding of thrips ecology, we discuss areas of future research and emphasize the importance of collaboration among different countries to enhance our overall understanding of the biology and ecology of thrips and to improve management programs for these widespread pests.