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Tree of Heaven (Ailanthus altissima (Mill.) Swingle) is a tree native to China which has invaded disturbed areas in many regions worldwide. Its presence endangers natural ecosystems by displacing native species, modifying habitats, changing community structures, and affecting ecosystem processes. Its invasive nature is enhanced by its high ability to reproduce both vegetatively through root regrowth and sexually through seeds. Seeds, which are wind dispersed, are the main mechanism by which this species reaches new habitats. When they germinate and develop the root system, roots emit new shoots that contribute to a rapid increase in the tree density and the subsequent expansion of the population nearby. The contradictory results about the ecological requirements for seeds to germinate and their degree of dormancy and longevity indicate the complexity and difficulty of understanding the mechanisms that govern the biology and adaptability of this plant. The management of this weed aims at its eradication, with programs based on herbicide applications carried out by injecting the active ingredient directly to the trunk. But, not many active ingredients have shown total control, so new ones should be tested in order to increase the range of available herbicides. During the last few decades, some biological agents have been identified, but their efficacy in controlling the tree and their safety for the local flora have not yet been determined. A correct management strategy should take into account all these aspects in order to contain the expansion of this species and, ultimately, allow its eradication. [ABSTRACT FROM AUTHOR]

Tetrapanax papyrifer, the rice‐paper plant, is an evergreen shrub and is traditionally used as a herbal medicine in China. In October 2021, a serious leaf spot disease was extensively observed on T. papyrifer in Guizhou, China. Given the limited information available about the aetiology of this disease, isolations were performed, the morphological characteristics and multi‐locus phylogenetic analysis of the fungus associated with the disease were described, and the pathogenicity tests and Koch's postulates were completed. To our knowledge, this is the first report of leaf spot on T. papyrifer caused by Alternaria tenuissima in China. Among 11 fungicides tested, 10% difenoconazole WDG had the best inhibition effect in vitro with EC50 values at 0.1 μg mL−1. This study provides new information for the identification and chemical control of Alternaria leaf spot of T. papyrifer. [ABSTRACT FROM AUTHOR]

This paper elaborates the occurrence factors and damage characteristics of Tetranychus urticae Koch in China, and emphatically summarizes three main control strategies of T. urticae, namely agricultural control, chemical control and biological control, as well as research progress in its resistance mechanisms. The problems existing in controlling T. urticae and its resistance management strategies are put forward, to provide a theoretical basis for the resistance management and comprehensive control of T. urticae. [ABSTRACT FROM AUTHOR]

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The bean flower thrips, Megalurothrips usitatus (Bagnall) is an economically important insect pest of cowpea, Vigna unguiculata (L.) Walp in south China. Spinetoram is a newly available commercial active ingredient in the spinosyn mode of action group of insecticides that has been recommended for thrips management in China. In this study, the toxicity and efficacy of spinetoram for controlling M. usitatus were evaluated and compared to six other conventional insecticides. In addition, the synergistic effects of adjuvants (Silwet 806, Silwet 618, AgroSpred 910, and AgroSpred Prime) mixed with spinetoram for thrips control on cowpea were evaluated in both the laboratory and the field. Results of this study showed that spinetoram had higher toxicity and field efficacy of M. usitatus than other tested insecticides. A significant increase in efficacy was observed when spinetoram was applied at a recommended rate of 0.67 ml/L, mixed with Silwets (806 and 618) at the rate of 0.5 ml/L. Reductions of 50% and 40% in thrips infestation in the field over treatments without adjuvants were observed 3- and 7-days posttreatments, respectively. However, no significant reduction of M. usitatus was recorded when spinetoram was mixed with AgroSpreds (910 and Prime). Furthermore, no significant differences were found in thrips infestation between spinetoram sprayed alone at the rate of 0.67 ml/L and a reduced rate of spinetoram (0.45 ml/L) mixed with Silwets (806 and 618). The current research shows that Silwets mixed with spinetoram has a synergistic effect in the management of thrips. [ABSTRACT FROM AUTHOR]

Culm rhomboid rot is a new disease of Moso bamboo (Phyllostachys edulis) and mainly occurs on Moso bamboo grown at an altitude above 800 m. The typical symptoms start with black spots and irregular shapes, which expand vertically into an elongated, fusiform, or rhomboid shape up to 15 cm in length. Eleven fungal isolates were isolated from infected tissue, and the isolate BBB1 was confirmed as the pathogen following Koch's postulates in vitro and in vivo. Regarding morphology, BBB1 was identified as Arthrinium sp.–conidia single-celled, brown to dark, smooth, globose to subglobose, with an equatorial slit, 5.0–9.3 × 3.1–7.3 μm in size. The conidiophores were reduced to conidiogenous cells, pale brown to dark, smooth, and ampulliform. Phylogenetic analysis based on ITS-TEF1-α-TUB2 concatenate sequences identified BBB1 as A. arundinis. Furthermore, the sensitivity of the pathogen against six common fungicides was investigated with mycelial growth assays. Prochloraz exhibited the most potent inhibition with an EC50 value of 0.019 mg/L; another effective fungicide was difenoconazole, with an EC50 value of 0.195 mg/L. This is the first report of A. arundinis causing culm rhomboid rot of Moso bamboo in China; the results provide a basis for managing Moso bamboo culm rhomboid rot. [ABSTRACT FROM AUTHOR]

There is increasing concern about the toxic effects of chemical pesticides on human health and the environment. Many alternatives, however, are viewed as impracticable or inefficient for agricultural needs. Here, a sustainable, environmentally friendly strategy was designed for the control of major rice insect pests (i.e. Nilaparvata lugens, Cnaphalocrocis medinalis and Chilo suppressalis) with minimal impact on natural enemies via selection of a specific entomopathogenic fungal strain for use as a biological control agent. In large-scale multiyear field applications, Metarhizium anisopliae CQMa421 was shown to act as effectively as chemical pesticides for pest control. Rice pest control applications in all major rice-producing provinces in China covering > 6000 hectares, performed over a period of 8 years (2011–2018), showed equal rice harvest yields between the use of the fungal pathogen versus chemical pesticides. More importantly, the use of the specific fungal pathogen isolated by this strategy resulted in an increase in beneficial insects and other animals. These long-term field evaluation data and large-scale application results demonstrated the feasibility of shifting from chemical dependency to more nuanced approaches for pest control for maintaining agricultural productivity while protecting natural enemies. With this strategy, new specific fungal strains can also be isolated to control the main pests of other crops. [ABSTRACT FROM AUTHOR]

Gray mold, caused by Botryfis cinerea. is a devastating disease that causes significant yield losses in various economically important plants. Fungicide application is one of the main strategies for management of gray mol however, B. cinerea has developed resistance to various groups of fungicide. In China, benzimidazole - dicarboximide - and quinone outside inhibitor-resistant populations of B. cinerea have become dominant. Substitute mutations in fungicide target genes are responsible for resistance in B. cinerea. Based on known resistance mechanisms, molecular methods including loop-mediated isothermal amplification have been developed for rapid detection of resistant isolates of B. cinerea. Because B. cinerea is able to quickly develop resistance to various fungicides, various integrated strategies have been implemented in the last decade, including biological and agricultural practices, to manage fungicide resistance in B. cinerea. [ABSTRACT FROM AUTHOR]

White clover ( Trifolium repens L.) is an excellent quality forage legume species with superior planting efficiency, which reduces the cost of artificial weeding and nitrogen fertilizer inputs, and has feeding and economic value. However, from June to September 2022, severe stem rot affected the yield and quality of white clover crops in Harbin, Heilongjiang Province, China. The aim of this study was to identify the causative agents of the disease. Overall, Colletotrichum truncatum (6 isolates) and C. destructivum (10 isolates) were obtained from rotten white clover stems and identified based on morpho-molecular characteristics and phylogenetic analyses. Pathogenicity tests of the isolates revealed that C. destructivum had a higher pathogenicity to white clover than C. truncatum . In addition, all isolates were highly pathogenic to broad bean, fodder soybean, soybean, pak choi, and chickpea, were pathogenic to mint, and did not infect corn, wheat, or cilantro. C. destructivum and C. truncatum isolates were very sensitive to tebuconazole and pyraclostrobin, with EC 50 values of 0.54 to 0.70 μg/ml and 0.42 to 0.62 μg/ml, respectively, efficacies ranging between 93.2 to 94.9% and 90.2 to 95.2% at 600 μg/ml and 450 μg/ml, respectively, and EC 90 values of 1.88 to 13.36 μg/ml and 1.32 to 23.39 μg/ml, respectively. Therefore, intercropping of host and nonhost plants and chemicals can be considered to control stem rot in white clover. These results provide a basis for controlling C. destructivum and C. truncatum in white clover in China., Competing Interests: The author(s) declare no conflict of interest.

Chinese fir is an extremely important economic tree species in southern China. In recent years, 74.5% of Chinese fir saplings suffered from shoot blight in Shunchang County, Nanping City, Fujian Province, China. Seventeen isolates were collected from rotten shoots, and their pathogenicity was confirmed following Koch's postulates. The five pathogenic isolates were identified as belonging to the genus Bipolaris based on morphological characteristics, including septate and geniculate conidiophores, smooth to slightly verruculose conidiogenous nodes, dematiaceous phragmospore conidia, oblong or fusiform conidia, and slightly protruding or truncate hilum on conidia, but the number of pseudosepta (3 to 11, mostly 5 to 8) and the size of conidia ([22.81 to 116.13] × [9.16 to 26.58] μm) are different from those of the known species of Bipolaris . A phylogenetic analysis based on ITS, GAPDH , and Tef1-α sequences determined that the five strains belong to a new species of Bipolaris , and the name Bipolaris fujianensis sp. nov. is proposed. The fungicide sensitivity of the pathogen strain Cfsb3 was further evaluated using eight fungicides. Flusilazole, difenoconazole, tebuconazole, and propiconazole exhibited high toxicity to Cfsb3, and the effective concentration inhibiting 50% (EC 50 ) of mycelial growth was 0.08, 0.20, 0.34, and 0.36 μg/ml, respectively, for these four fungicides. Flusilazole, difenoconazole, and iprodione inhibited B. fujianensis by 100% on detached Chinese fir shoots at their recommended concentrations, but azoxystrobin and thiram were ineffective. In conclusion, this study reported an emerging pathogen of Chinese fir sapling shoot blight and proposed triazole and dicarboximide fungicides for disease control., Competing Interests: The author(s) declare no conflict of interest.

Chinese herbal medicine is the strategic resource and the basis for the development of traditional Chinese medicine. Dendrobium officinale, “8 famous Chinese herbal medicine” and other Chinese herbal medicinal materials production in Zhejiang play an important position in China. With the rapid development in recent years, the pest damage, the pesticide pollution and residue due to improper use have become risks to the quality and safety of Chinese herbal medicines. Since the relative researches focused on the description of pest’s symptoms and field trails of control were a little later and fewer. And the basic researches were very weak. There was few registered pesticides for the farmers. And nearly no standards of pesticide residues and the safe usage procedures of pesticides were provided. The corresponding resistance research was rare. Therefore, that there were many works need to be done for the scientific application of pesticides. This review summarized the status of chemical control on the pests of characteristic Chinese herbal medicines in Zhejiang Province in the past 20 years, including aspects such as systematical identification of the pests, assay pesticides in laboratory and fields, residues and resistance. According to the weaknesses and major problems, we proposed that the basic researches of pests control and quality safety, the screening of new pesticides, pesticides registration and relative standards, pesticides resistance monitoring and management, the research and promotion of comprehensive management technology, safe application of pesticides should be strengthened and accelerated in order to supply theoretical basis and technological supports for the pests control of Chinese herb and to provide references for chemical control of pests on other small crops. [ABSTRACT FROM AUTHOR]

Weed occurrence and damage in public green lawn of Suzhou urban area was assessed using five-grade weed visual survey method. The occurrence and damage of weeds in public green lawn of Suzhou City was very common. There were totally 67 species of weeds in green lawn, with the density of 6.5 plant /m², the relative abundance of 7.6% , the relative coverage of 10.3% , the relative height and the occurrence frequency of 100%, and the overall damage level of weeds was above the forth level. There were 14 species of major weeds causing damage, and 15 species of weeds were found to pose regional damage. Haloxyfop-R-methyl or Ping'an-14 could be applied to control grassy weeds in clover lawns, with the herbicidal effect above 90%. MCPA, fluroxypyr, or clopyralid could be administrated alone to control broadleaf weeds in Cynodon dactylon or Festuca elata lawn, with the herbicidal effect above 85%. Since the weed species in weed communities of lawn were different, the types of herbicides should be targeted, or SD additives could be added to improve the herbicidal effect. [ABSTRACT FROM AUTHOR]

Leaf blight caused by Stemphylium solani is a major fungal disease of garlic (Allium sativum) in central China where it has caused severe crop losses during the winter growing season from the end of autumn to the middle of spring. Epidemiology, cultivar resistance, and chemical controls were investigated during the 2006 to 2008 growing seasons in Dangyang County to improve disease control methods. Disease severity monitoring revealed that the activity of S. solani was variable between growing seasons, and this may have been due to weather conditions. Disease severity was positively correlated with increasing temperatures, but no consistent relationship was found between total rainfall and disease. Additionally, the study demonstrated that conidia and mycelium of S. solani could survive in garlic debris for long periods and serve as the primary inoculum source for the subsequent season. Relatively few of the commonly grown cultivars had high levels of resistance to leaf blight. Garlic cultivars 'Qingganruanye', 'Ruanruanye' and 'Zixuan-2' were among the most resistant, but except for 'Zixuan-2', did not produce sufficient harvestable bolts as would be desirable for the local market. All fungicide treatments applied to cloves used as planting material seemed to promote seedling emergence, but significant effects (P = 0.05) were observed only with fludioxonil (0.05 g kg-1) and thiram (1.25 g kg-1). Fungicide applications in the field were effective in controlling leaf blight, and flusilazole (50 g ha-1), flusilazole plus famoxadone (50 g plus 104 g ha-1) or mancozeb (350 g ha-1) had the highest efficacy in reducing leaf blight severity. [ABSTRACT FROM AUTHOR]

Abstract: The paper determines what might be the factors beneath the limited or reduced effectiveness being observed in China. The analysis is based on the data collected for several years from many locations in the Yangtze River Valley Varietal Experiment Network. All varieties declared to be Bt-cotton were confirmed to have the Bt-gene, the expression of which was assessed in three ways: through the analysis of Bt-protein production and through indoor and outdoor bioassays. Gene expression varied substantially between varieties and between years for the few varieties which were tested in two subsequent years. The Bt-cotton varieties being sown cannot control bollworms totally and this led to spray chemicals regardless of the real infestation level. Farmers are hence paying high prices for varieties which are not totally resistant to bollworms and pest control costs are not reduced to the extent that they might expect, lowering the profitability of cotton production. [Copyright &y& Elsevier]

More than 200 species of weeds are infesting main crop fields in China, among which approximately 30 species are major weeds causing great crop yield losses. About 35.8 million hectares of crop fields are heavily infested by weeds and the annual reduction of crop yields is 12.3–16.5% (weighted average). Along with rural economic development, approximately 50% of the main crop fields undergo herbicide application. Chemical weed control has changed cultural practices to save weeding labor in rice, wheat, maize, soybeans and cotton. At the same time, continuous use of the same herbicides has caused weed shift problems and weed resistance to herbicides. Consequently, integrated weed management in main crops is being developed. [ABSTRACT FROM AUTHOR]

The fungicide fludioxonil is one of the most effective single-site fungicides available for managing flower blight caused by Botrytis cinerea on fruit and ornamental crops. Although low and moderate levels of resistance to fludioxonil have been reported in the pathogen across the United States and Europe, high resistance has been reported only from greenhouses in China. In this study, two B. cinerea isolates with high resistance (half maximal effective concentration >100 µg/ml) to fludioxonil were detected on ornamental calibrachoa flowers grown in a greenhouse. These isolates exhibited stable resistance for >20 generations, produced symptoms on calibrachoa flowers sprayed with label rates of fludioxonil, and displayed in vitro fitness penalties with decreased mycelial growth ( P < 0.0001) and sporulation ( P < 0.0001) compared with sensitive isolates. Highly resistant isolates were identified as MDR1h, containing the ΔL/V497 deletion in mrr1 . However, resistance levels and in vitro fitness parameter characteristics were not consistent with this phenotype. One isolate contained the mutation L267V between HAMP domains 1 and 2 of the Bos-1 gene, and both isolates exhibited high osmotic sensitivity and reduced glycerol accumulation in the presence of fludioxonil, indicating that high resistance of these isolates may be associated with the high-osmolarity glycerol mitogen-activated protein kinase pathway.

Gray mold, caused by Botrytis cinerea , is a devastating disease that causes significant yield losses in various economically important plants. Fungicide application is one of the main strategies for management of gray mold; however, B. cinerea has developed resistance to various groups of fungicide. In China, benzimidazole-, dicarboximide-, and quinone outside inhibitor-resistant populations of B. cinerea have become dominant. Substitute mutations in fungicide target genes are responsible for resistance in B. cinerea . Based on known resistance mechanisms, molecular methods including loop-mediated isothermal amplification have been developed for rapid detection of resistant isolates of B. cinerea. Because B. cinerea is able to quickly develop resistance to various fungicides, various integrated strategies have been implemented in the last decade, including biological and agricultural practices, to manage fungicide resistance in B. cinerea .

The field experiment was conducted at two farms at Jiusan in Heihe (the fourth accumulated temperature zone) and at Lindian County of Daqing (the second accumulated temperature zone), both sites located in Heilongjiang Province, China. With soybean Kenfeng 41 as the test material, uniconazole (S 3307 , 50 mg·L -1 ) and 2-N, N- diethylamino ethyl caproate (DTA-6, 50 mg·L -1 ) were sprayed on leaves in the early flowering period of soybean. Through grey correlation analysis, the main factors affecting soybean yield were examined, and the differences of the light and heat utilization efficiency and soybean yield in two ecological conditions were compared. The regulation effects of chemical control technology on the light and heat utilization efficiency of soybean were explored. The results showed that the total surface radiation and ≥10 ℃ effective accumulated temperature were the main factors affecting soybean yield in both areas compared with rainfall and sunshine hours. The light and heat utilization efficiency from sowing to flowering period was significantly positively correlated with dry matter accumulation, and that from flowering to podding period was significantly positively correlated with dry matter accumulation per plant. There was a significant positive correlation between yield and dry matter accumulation, grain number per plant, grain mass per plant and 100-grain mass at seedling stage to podding stage. S 3307 and DTA-6 could significantly improve light and heat utilization efficiency and soybean yield in both areas. S 3307 showed the better regulation function to impact the light and heat utilization efficiency and yield than DTA-6 in both sites. In the two ecological areas of Jiusan and Lindian, spraying S 3307 increased light utilization efficiency by 13.6% and 17.1%, and increased heat utilization efficiency by 14.1% and 17.2%, respectively. The yield by spraying S 3307 was increased by 14.1% and 17.3% separately in Jiusan and Lindian. Therefore, it is the effective way to enhance resources utilization and achieve high-yield by using the reasonable chemical control technology.