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【Objective】The study aimed to clarify the value of microbial fertilizer in the production of Chinese chive, and screen the best scheme for combined application of microbial fertilizer with chemical fertilizer in the high quality and safe production of Chinese chive and control of Bradysia odoriphaga.【Method】Xuejiu 791 was taken as the research object, 8 treatments of microbial fertilizer combined with chemical fertilizer were set up, namely, the recommended amount of chemical fertilizer combined with 30%, 50%, 70%, 100% of the recommended amount of microbial fertilizer (T2~T5), and the recommended amount of microbial fertilizer combined with 70%, 50%, 30%, and 0% of the recommended amount of chemical fertilizer (T6~T9). The effects of different fertilization schemes on the yield and growth traits of Chinese chives was estimated by indoor single factor experiment to screen the better fertilization schemes; and the effects of above better fertilization schemes on the yield and quality of Chinese chives and the occurrence of B. odoriphaga were verified by field experiments.【Result】The indoor experiment showed that the growth traits of Chinese chives were significantly improved by microbial fertilizer, with plant height, stem diameter, maximum leaf width, plant weight per plant and number of fibrous root significantly increased. Among all the fertilization schemes, the best growth traits of Chinese chives were found in T5, T6, and T7 treatment, especially for plant height, which was 27.87, 27.59 and 28.84 cm, respectively, and significantly differed from that in other treatments. The weight per plant was 0.99, 0.93 and 0.94 g, respectively, which was significantly different from that in other treatments except T4 and T9. The growth traits of Chinese chives did not differ among T5, T6 and T7. Based on the above results and the economic point of view, T6 and T7 were judged to be the optimal fertilizer scheme. The result of field experiment showed that the application of T6 scheme of indoor experiment (FT6 treatment) significantly increased the plant weight, stem diameter, pseudostem length, plant height, maximum leaf width and number of fibrous root of Chinese chives in greenhouse by 29.41%, 1.70%, 12.19%, 7.58%, 17.23% and 40.60%, respectively, compared to the control (FT1). The application of T7 scheme of indoor experiment in field (FT7 treatment) significantly increased the weight per plant, stem diameter, pseudostem length, maximum leaf width and number of fibrous root of Chinese chives by 23.22%, 4.21%, 11.94%, 9.47% and 16.99%, respectively, compared to the control (FT1), but the increase amplitude of each growth character was less than that in FT6. The yield of Chinese chives in FT6 and FT7 treatment was significantly increased by 48.39% and 12.99%, respectively compared to FT1. The quality of Chinese chives in FT6 and FT7 treatment was significantly improved, soluble sugar content and soluble protein content were increased by 32.72%, 10.45% and 6.76%, 6.60%, respectively, compared to FT1. The growth traits of Chinese chives in FT6 were better than those in FT7. FT6 and FT7 treatment inhibited the occurrence of B. odoriphaga, and the inhibition rates were 50.15% and 22.16%, respectively, compared to the control.【Conclusion】Compared with the single application of chemical fertilizer, the combined application of microbial fertilizer and chemical fertilizer effectively improve the yield and quality of Chinese chive, and inhibit the occurrence of B. odoriphaga. The best recommended scheme was 70% of the recommended amount of fertilizer combined with 100% of the recommended amount of microbial fertilizer.

To explore the feasibility of adjusting the photoperiod to regulate the life parameters and predation ability of Harmonia axyridis Pallas in greenhouses during the winter, life tables were constructed for H. axyridis under the three following photoperiods: 9L:15D (light/dark), 12L:12D, and 16L:8D at 15 °C, an average greenhouse temperature during the winter when aphids severely damage vegetables. The effects of photoperiods on predation by this ladybird were tested in both laboratory and greenhouse settings. The results showed that increased illumination promoted the development and reproduction of H. axyridis; under medium and long photoperiods, the pre-adult periods were 3.61 days and 4.34 days shorter than that under the short photoperiod, respectively, and the fecundity increased by 1.78 and 2.41 times. Population parameters r, λ, and R0 increased as illumination time increased, whereas T decreased. Increased illumination also increased the predation by third- and fourth-instar larvae and adults. The amounts of predation by fourth-instar larvae and adults increased by 22.16% and 75.09% under the medium photoperiod, and those under the long photoperiod increased by 71.96% and 89.64%, respectively. The numbers of Myzus persicae Sulzer predated by H. axyridis under the long photoperiod were higher than those under the short photoperiod in a greenhouse, and the predation parameters were influenced.

Abstract Frankliniella occidentalis (Pergande) has become an important vegetable pest worldwide because of its economic damage to crop production. However, it is difficult to control due to its unique living habits. In this study, the eggs of F. occidentalis were used as the target to explore the ovicidal activity of spirotetramat on the thrips and its effect on hatching, development and formation. After the treatment of spirotetramat, the LC50 value descreased with increased egg age using egg dipping method, and showed the same trend as the leaf dipping method verified on living plants. Through ultra-depth-of-field microscopy, scanning electron microscopy and transmission electron microscopy, the egg shell and internal structures of F. occidentalis eggs were studied. Spirotetramat can destroy the egg shells of F. occidentalis, resulting in shrinkage of the egg surface, sunken pores, egg deformities, egg shell rupture and other phenomena. This allows spirotetramat to enter the egg and destroy the egg structure, making the egg internal structure flocculent, fuzzy and unevenly distributed, which affects embryonic development and causes the nymphs to die before hatching. Therefore, the prevention and control of F. occidentalis using spirotetramat before damage is caused to crops should have a better effect.

It has been found that 5-hydroxytryptamine (5-HT) modulates the feeding of some insects, and this phenomenon was found in Harmonia axyridis (Pallas) by our previous study. An understanding of the 5-HT system in this beetle is helpful for utilizing 5-HT to modulate its predation to improve biological control efficiency, especially in greenhouses in winter in north China. This is because 5-HT influences diapause in insects by modulating the synthesis and release of prothoracic hormone (PTTH) and, therefore, influences feeding. To elucidate the molecular basis of the H. axyridis 5-HT system, reverse-transcription polymerase chain reaction (RT-PCR), multiple sequence alignment, and phylogenetic tree construction were used to identify the 5-HT receptor in H. axyridis, and quantitative real-time PCR (qRT-PCR) was used to analyze the expression pattern of these receptor genes in different developmental stages and in the nervous system (brain + ventral nerve cord), digestive tract, pectoral muscles, and gonads of the adult ladybird. The results showed that four 5-HT receptors were identified in H. axyridis, named 5-HT1AHar, 5-HT1BHar, 5-HT2Har, and 5-HT7Har. The four receptors were expressed at high levels in the adult stage, especially in 2-day-old adults, with expression levels of 18.72-fold (male) and 14.21-fold (female) of that in eggs for 5-HT1A, 32.27-fold (male) and 83.58-fold (female) of that in eggs for 5-HT1B, 36.82-fold (male) and 119.35-fold (female) of that in eggs for 5-HT2, and 165.47-fold (male) and 115.59-fold (female) of that in eggs for 5-HT7. The level of expression decreased with the advance of day-age in adults. The levels of expression of 5-HT1BHar, 5-HT2Har, and 5-HT7Har were low at the egg, larval, and pupal stages, and 5-HT1AHar was not expressed in the larval stage. The four receptors were expressed in the nervous system, digestive tract, pectoral muscles, and male and female gonads. The 5-HT1AHar was expressed at a high level in the pectoral muscle (6.75-fold of that in the nervous system), 5-HT1BHar in male gonads (1.02-fold of that in the nervous system) and the nervous system, 5-HT2Har in male gonads (5.74-fold of that in the nervous system), and 5-HT7Har in the digestive tract (1.81-fold of that in the nervous system). The results of this study will lay a foundation for research on the function of the 5-HT receptor by RNA interference in the regulation of predation by H. axyridis.

Maternal effects of heat shock are reported for some species of insects, but little is known about such effects in the western flower thrips (WFT) Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). WFT is a pest of vegetables in greenhouses worldwide. It is susceptible to high temperatures in its natural environment and is controlled using heat treatment in China. WFT population growth is suppressed by a brief exposure to a high temperature of 40°C or 45°C in the laboratory. To explore the mechanism by which high temperatures suppress the growth of WFT populations, as well as the effects of multiple heat treatments on WFT, we recorded the duration of development and survival of immature WFT, and the sex ratio (female/male) and fecundity of F1, F2, F3 and F4 adult females that developed after a single heat shock, and those of F2 offspring after a double heat shock. We also recorded the longevity and ovarian structure of adult females of the treated generation (P) and their F1, F2 and F3 offspring after a single heat shock. In addition, we determined whether the effects of a heat shock on second instar nymphs and adults differed. The results indicate that exposure of the parental generation to 41°C or 45°C for 2 h significantly prolonged the duration of development, reduced survival of immature WFT and altered the sex ratio (female/male), longevity and fertility of their adult female offspring. The effects of a heat shock of 41°C persisted for two generations, whilst the effect of heat shock of 45°C persisted for three generations. In addition, double heat shocks had more pronounced effects than a single heat shock. Heat shock administered to second instar nymphs resulted in a decrease in the number of ovarioles, whilst a heat shock administered to adults resulted in ovariole deformity. The maternal effects of heat shock in terms of the biological parameters of WFT, structure and number of ovarioles, are critical in determining the suppression of the growth at high temperatures of WFT populations.

Lysine crotonylation (Kcr) is a newly discovered posttranslational modification (PTM), which has been studied at the proteomics level in a few species, with the study of Kcr in female fertility and in insect species is still lacking. Harmonia axyridis (Pallas) is a well-known beneficial insect used as a natural biological control agent against aphids in agriculture. Here, global Kcr identification in ovarian tissue of H. axyridis at diapause stage was performed to reveal potential roles for Kcr in H. axyridis ovarian cellular processes, female fertility and diapause regulation. In total, 3084 Kcr sites in 920 proteins were identified. Bioinformatic analyses revealed the distribution of these proteins in multiple subcellular localization categories and their involvement in diverse biological processes and metabolism pathways. Carbohydrate and energy metabolism related cellular processes including citric acid cycle, glycolysis and oxidative phosphorylation appeared be affected by Kcr modification. In addition, regulation of translation and protein biosynthesis may reflect Kcr involvement in diapause in H. axyridis, with Kcr affecting ribosome activities and amino acid metabolism. Moreover, Kcr modulation H. axyridis ovary development regulation may share some common mechanism with Kcr participation in some disease progression. These processes and pathways were uncovered under diapause stage, but possibly not enriched/specific for diapause stage due to limitations of qualitative proteomics experimental design. Our results informs on the potential for Kcr modifications to regulate female fertility and insect physiology.

The western flower thrips, Frankliniella occidentalis, is an aggressive agricultural insect pest causing significant damage to a wide range of fruit, vegetable, and ornamental crops. Beauveria bassiana is a broad-host-range entomopathogenic fungus capable of infecting and killing F. occidentalis. Infection of thrips by B. bassiana strain BbYT12 using a concentration of 1 × 108 conidia/mL resulted in 81.48% mortality in adults in 6 d (LT50 = 90 ± 15.1 h). Scanning electron microscopy of the infection process revealed preferential adhesion and germination of fungal spores to inter-segmental folds or grooves on the insect body surface with penetrating germlings and extended hyphae visualized during the initial stages of infection (6–24 h). Histological analyses showed the appearance of in vivo hyphal bodies in sagittal sections and the fat body as early as 24 h post-infection. Within 72 h, hyphal bodies and hyphae could be found throughout the infected organism including in the midgut, Malphigian tubules, alimentary canal, ovarioles (in females), and an extended hyphal network could be seen on insect cadavers (>72 h post-infection). Real-time RT-PCR analyses of the expression of select genes implicated in virulence including the Pr1 protease, beauvericin synthase, involved in the production of the secondary metabolite beauvericin, two cytochrome P450 monooxygenases implicated in cuticular hydrocarbon degradation, two multidrug efflux proteins, a perilipin involved in lipid storage, and the Hog1 MAP kinase and protein kinase A signaling factors revealed discrete patterns of infection-time dependent expression. These data provide basic insights into the process of B. bassiana infection of F. occidentalis.

Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a reliable technique for measuring and evaluating gene expression during variable biological processes. To facilitate gene expression studies, normalization of genes of interest relative to stable reference genes is crucial. The western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), the main vector of tomato spotted wilt virus (TSWV), is a destructive invasive species. In this study, the expression profiles of 11 candidate reference genes from nonviruliferous and viruliferous F. occidentalis were investigated. Five distinct algorithms, geNorm, NormFinder, BestKeeper, the ΔCt method, and RefFinder, were used to determine the performance of these genes. geNorm, NormFinder, BestKeeper, and RefFinder identified heat shock protein 70 (HSP70), heat shock protein 60 (HSP60), elongation factor 1 α, and ribosomal protein l32 (RPL32) as the most stable reference genes, and the ΔCt method identified HSP60, HSP70, RPL32, and heat shock protein 90 as the most stable reference genes. Additionally, two reference genes were sufficient for reliable normalization in nonviruliferous and viruliferous F. occidentalis. This work provides a foundation for investigating the molecular mechanisms of TSWV and F. occidentalis interactions.

Background: The Phosphate transporter 1 (PHT1) gene family has crucial roles in phosphate uptake, translocation, remobilization, and optimization of metabolic processes using of Pi. Gene duplications expand the size of gene families, and subfunctionalization of paralog gene pairs is a predominant tendency after gene duplications. To date, experimental evidence for the evolutionary relationships among different paralog gene pairs of a given gene family in soybean is limited. Results: All potential Phosphate transporter 1 genes in Glycine max L. (GmPHT1) were systematically analyzed using both bioinformatics and experimentation. The soybean PHT1 genes originated from four distinct ancestors prior to the Gamma WGT and formed 7 paralog gene pairs and a singleton gene. Six of the paralog gene pairs underwent subfunctionalization, and while GmPHT1;4 paralog gene experienced pseudogenization. Examination of long-term evolutionary changes, six GmPHT1 paralog gene pairs diverged at multiple levels, in aspects of spatio-temporal expression patterns and/or quanta, phosphates affinity properties, subcellular localization, and responses to phosphorus stress. Conclusions: These characterized divergences occurred in tissue- and/or development-specific modes, or conditional modes. Moreover, they have synergistically shaped the evolutionary rate of GmPHT1 family, as well as maintained phosphorus homeostasis at cells and in the whole plant. [ABSTRACT FROM AUTHOR]