YBX1 inhibits mitochondrial-mediated apoptosis in ischemic heart through the PI3K/AKT signaling pathway

Background:Myocardial infarction(MI)is associated with higher morbidity and mortality in the world,especially in cold weather.YBX1 is an RNA-binding protein that is required for pathological growth of cardiomyocyte by regulating cell growth and protein synthesis.But YBX1,as an individual RNA-binding protein,regulates cardiomyocytes through signaling cascades during myocardial infarction remain largely unexplored.Methods:In vivo,the mouse MI model was induced by ligating the left anterior descending coronary artery(LAD),and randomly divided into sham operation group,MI group,MI+YBX1 knockdown/overexpression group and MI+negative control(NC)group.The protective effect of YBX1 was verified by echocardiography and triphenyltetrazolium chloride staining.In vitro,mitochondrial-dependent apoptosis was investigated by using CCK8,TUNEL staining,reactive oxygen species(ROS)staining and JC-1 staining in hypoxic neonatal mouse cardiomyocytes(NMCMs).Results:YBX1 expression of cardiomyocytes was downregulated in a mouse model and a cellular model on the ischemic condition.Compared to mice induced by MI,YBX1 overexpression mediated by adeno-associated virus serotype 9(AAV9)vector reduced the infarcted size and improved cardiac function.Knockdown of endogenous YBX1 by shRNA partially aggravated ischemia-induced cardiac dysfunction.In hypoxic cardiomyocytes,YBX1 overexpression decreased lactic dehydrogenase(LDH)release,increased cell viability,and inhibited apoptosis by affecting the expression of apoptosis related proteins,while knockdown of endogenous YBX1 by siRNA had the opposite effect.Overexpression of YBX1 restored mitochondrial dysfunction in hypoxic NMCMs by increasing mitochondrial membrane potential and ATP content and decreasing ROS.In hypoxic NMCMs,YBX1 overexpression increased the expression of phosphorylated phosphatidylinositol 3 kinase(PI3K)/AKT,and the anti-apoptosis effect of YBX1 was eliminated t by LY294002,PI3K/AKT inhibitor.Conclusion:YBX1 protected the heart from ischemic damage by inhibiting the mitochondrial-dependent apoptosis through PI3K/AKT pathway.It is anticipated that YBX1 may serve as a novel therapeutic target for MI.

Notum protects against myocardial infarction-induced heart dysfunction by alleviating cardiac fibrosis

Background and Objective:Cardiac fibrosis is a pathological reparative process that follows myocardial infarctionand is associated with compromised cardiac systolic and reduced cardiac compliance.The Wnt signaling pathway is closely implicated in organ fibrosis,and Notum,a highly conserved secreted inhibitor,modulates Wnt signaling.The objective of this study was to explore the role and mechanism of Notum in cardiac fibrosis.Methods:A mouse model of cardiac remodeling was established through left coronary artery ligation surgery,with the addition of Notum injection following myocardial infarction surgery.The protective effect of Notum on myocardial infarction was assessed by evaluating cardiac function,including survival rate,echocardiographic assessment,and cardiac contraction analyses.Inflammatory cell necrosis and infiltration were confirmed through H&E and Masson staining.The expression of fibrosis-related genes andβ-catenin pathway markers was detected using Western blot quantificational RT-PCR(qRT-PCR).Additionally,EdU,wound healing,and immunofluorescence staining analyses were performed to detect the effect of Notum's in transforming growth factor beta-1(TGF-β1)induced myofibroblast transformation.Results:The administration of Notum treatment resulted in enhanced survival rates,improved cardiac function,and decreased necrosis and infiltration of inflammatory cells in mice subjected to left coronary artery ligation.Furthermore,Notum effectively impeded the senescence of cardiac fibroblasts and hindered their pathological transformation into cardiac fibroblasts.Additionally,it significantly reduced collagen production and attenuated the activation of the Wnt/β-catenin pathway.Our preliminary investigations successfully demonstrated the therapeutic potential of Notum in both fibroblasts in vitro and in a mouse model of myocardial infarction-induced cardiac fibrosis in vivo.Conclusion:Notum inhibition of the Wnt/β-catenin signaling pathway and cardiac fibroblast senescence ultimately hampers the onset of cardiac fibrosis.Our findings suggest that Notum could represent a new therapeutic strategy for the treatment of cardiac fibrosis.

Establishment and Application of Prevention and Control Techniques of New Sugarcane White Leaf Disease

Aiming at the basic and key technical problems in prevention and control of sugarcane white leaf disease(SCWL),this study systematically overcame key technical bottleneck of prevention and control of new SCWL after 10 years of collaborative research,and achieved several innovative achievements.SCWL phytoplasmas newly recorded in China and the new subgroup of SCWL phytoplasmas(16SrXI-D)were discovered for the first time in Yunnan,and the whole genome analysis of the epidemic subgroup was completed.The main transmission source of SCWL pathogens has been identified as infected seed canes,and Tettigoniella viridis and Clovia conifer were newly discovered as vectors for virus transmission.The disease resistance of 25 main varieties was identified,and 10 control varieties were selected.The prevention and control strategy of"emphasizing early warning,strictly carrying out quarantine,blocking the vectors and controlling residual plants"was put forward,and a comprehensive prevention technique was established through integration of various techniques,and standardized technical regulations were formulated for demonstration application.The promotion and application of these achievements have realized scientific prevention and control of SCWL,effectively curbed the spread of SCWL,and ensured the safety of sugarcane producing areas in China,achieving great economic,social and ecological benefits and providing technical support for high-quality development,loss reduction and efficiency improvement of China's sugar industry.

Efficacy of High-efficiency Formula Pesticides for Controlling Sesamia inferens Walker and Ceratovacuna lanigera Zehntner

[Objectives]This study was conducted to screen high-efficiency formula pesticides and precise and efficient application techniques for the prevention and control of Sesamia inferens Walker and Ceratovacuna lanigera Zehntner.[Methods]Field efficacy trials were conducted using different combinations of 70%directed enhanced thiamethoxam seed treatment dispersible powder and 46%monosultap·Bacillus thuringiensis wettable powder.[Results]70%directed enhanced thiamethoxam ZF 450 g/hm^(2)+46%monosultap·B.thuringiensis WP 2250 g/hm^(2)had good control effects on both S.inferens and C.lanigera,so it was an ideal high-efficiency formula pesticide for controlling sugarcane S.inferens and C.lanigera.From January to May,combining with new plant or perennial root cultivation management,70%directed enhanced thiamethoxam ZF 450 g/hm^(2)can be evenly spread on sugarcane ditches and sugarcane stumps after being well mixed with fertilizers applied per hectare,and covered with soil in a timely manner,and during the peak incubation period of the first and second generation of S.inferens eggs from March to May,46%monosultap·B.thuringiensis WP 2250 g/hm^(2)was sprayed to the leaf surface in the mixture with water 675 kg with an electric backpack or a motorized sprayer.In such a way,the control efficacy on dead heart seedlings could reach over 89.8%,and that on C.lanigera could reach 100%.Meanwhile,it could effectively and concurrently control thrips,and the increases in yield and sugar content could reach 29310 kg/hm^(2)and 5.9 percentage points,respectively.[Conclusions]The promotion and application of the formula pesticide could achieve precise application and control of sugarcane pests,and improvement of sugarcane quality and planting efficiency,and help promote green prevention and control of sugarcane diseases and pests and the sustained high-quality development of the sugar industry.

Establishment and Application of Identification Methods for Resistance to Sugarcane White Leaf Disease(SCWL)

[Objectives]This study was conducted to establish simple, efficient, stable, standardized and practical identification methods for sugarcane resistance to white leaf disease(SCWL), and promote the breeding for sugarcane resistance to SCWL. [Methods]The identification technology of sugarcane resistance to SCWL was systematically studied and explored from the aspects of sugarcane material treatment and planting, inoculation liquid preparation, inoculation method, disease investigation, grading standard formulation, etc., and two sets of simple, efficient, stable, standardized and practical accurate identification methods for sugarcane resistance to SCWL were created for the first time, namely, the seed cane coating inoculation method and the stem-cutting inoculation method at the growth stage. The seed cane coating inoculation method includes the steps of directly screening SCWL phytoplasma, extracting juice from cane and adding 10 times of sterile water to prepare an inoculation liquid, spraying seed cane on plastic film to keep moisture, planting the inoculated materials in barrels in an insect-proof greenhouse for cultivation, investigating the incidence rate 30 d after inoculation, and evaluating the disease resistance according to the 1-5 level standard. The method of stem-cutting inoculation includes the steps of directly screening sugarcane stems carrying SCWL phytoplasma and adding 10 times of sterile water to prepare an inoculation liquid, cultivating the identification materials in an insect-proof greenhouse, dropping 100 μl of the inoculation liquid into each root incision with a pipette gun at the age of 6 months, investigating the incidence rate 20 d after planting, and evaluating the disease resistance according to the 1-5 level standard. [Results] The two methods are similar to the natural transmission method. After inoculation, SCML occurred significantly, with high sensitivity and good reproducibility. The results of resistance identification were consistent with those of natural disease in the field. Through the two inoculation methods and field natural disease investigation, the resistance of 10 main cultivars to SCML was identified, which was true and reliable. [Conclusions] This study can provide standard varieties for identification of SCML resistance in the future.

Investigation on Outbreak of Sesamia inferens and Smut in Cane-growing Regions of Yunnan Province

[Objectives]This study was conducted to clarify the outbreak and disaster characteristics of Sesamia inferens Walker and smut in cane-growing regions in the low-latitude plateau of Yunnan Province,where there is continuous high temperature and drought in spring and summer.[Methods]A systematic investigation and analysis was conducted on different varieties in different types of fields in 16 cane-growing regions with outbreak of S.inferens and smut in Yunnan from 2019 to 2021.[Results]The outbreak of S.inferens and smut in cane-growing regions in the low-latitude plateau of Yunnan Province resulted in an average percent of dry hearts in the range of 17.3%-56.3%,and as high as 84.0%in severe cases.70%thiamethoxam seed treatment dispersible powder and clothianidin or thiamethoxam fertilizer granules were ineffective against S.inferens,while 10%monosultap·thiamethoxam or 10%clothianidin·monosultap granules had a significant control efficacy on S.inferens.The average diseased plant rate ranged from 14.8%to 89.7%in susceptible varieties with smut,and was as high as 100%in severe cases.ROC 1,Yuetang 93-159,Yuetang 00-236,and Liucheng 05-136 had strong resistance,with an average diseased plant rate of 0-5.5%and the highest rate of 7.6%.S.inferens and smut both broke out in cane-growing regions with an altitude below 1200 m.It is recommended to pay attention to disease and pest monitoring in cane-growing regions with an altitude below 1200 m,and combine it with the management of new plants and ratoon plants to effectively prevent and control the first and second generation of S.inferens-infested seedlings from March to May.It is also recommended to strengthen the promotion and application of excellent disease-resistant varieties,so as to achieve a reasonable distribution of varieties and fundamentally control the outbreak and epidemic of sugarcane smut.[Conclusions]This study provides a basis for the effective prevention and control of catastrophic S.inferens and smut caused by extreme climate.

Geostatistical Analysis of Spatial Distribution and Dynamics of Dead Heart of Sugarcane Seedlings Caused by Borer

Dead heart of sugarcane is an important symptom caused by borer attack. In the present study, the spatial distribution and dynamics of dead heart of sugarcane in the field were investigated based on geostatistical analysis, and semivariograms were computed in four separate directions(0°, 45°, 90° and 135°) and fitted with various theoretical models to determine the best fitted one. The Ordinary Kriging was used to interpolate spatial data. The results revealed that the density of dead hearts of sugarcane increased in a single-peak pattern, and the degree of spatial aggregation and random variation both decreased with the increase in the density of dead heart. In addition, dead heart of sugarcane caused by borer exhibited spatial aggregation.With the increase in the density of dead heart, the degree of spatial aggregation decreased, while the correlation increased. Kriging interpolation indicated that the correlation between the spatial patches was weak in early seedling stage, and became strong in middle and late seedling stage.

Occurrence and Epidemic Dynamics and Accurate Prevention and Control of Important Sugarcane Pests and Diseases in the Sugarcane Areas of Yunnan

Based on investigation and research, according to the current actual production of sugarcane, the occurrence dynamics and outbreak causes of important pests and diseases that seriously affect sugarcane production were summarized, and accurate and efficient green prevention and control technology was put forward according to the occurrence and damage characteristics of important pests and diseases, such as strengthening sugarcane introduction and quarantine, breeding and selecting varieties resistant to diseases and pests, promoting the use of detoxified healthy seedlings vigorously, applying lamp trapping technology on a large scale, scientifically guiding and promoting biological prevention and control technology, practically promoting the precise and efficient application of slow-release long- acting and low toxic pesticides, strengthening field management, spraying pesticides in time at the early stage of a disease, and doing a good job of monitoring and emergency prevention and control of sudden pests.

Unmanned Aerial Vehicle Control of Major Sugarcane Diseases and Pests in Low Latitude Plateau

This research was aimed at the defects in traditional artificial spraying control method and the problems such as the difficulty in pesticides applying,labor shortage and low operating efficiency in the middle and late stage of sugarcane high stalk crops.The aerial pesticide application technology for sugarcane main diseases and pests was systematically developed and demonstrated from the aspects of aircraft type choice,selection of special pesticides and auxiliaries,integration of pesticides and equipment,field operation,technical specifications,and large-scale application organization mode.The UAV model and flight technical parameters suitable for the sugarcane planting area in low-latitude plateau were analyzed,and the optimal agent formulation combination and application technology of the UAV flight control were screened out,and the UAV flight control was applied to the major sugarcane pests and diseases control in the low-latitude plateau in large scale(UAV flight control was popularized and applied to 15 527 hm 2 in 2018).The research results provided mature whole-process technical support for the normalization of the application of the UVA flight control of major sugarcane pests and diseases.The UAV control technology for major sugarcane pests and diseases had the advantages of ultra-low pesticides applying dosage and high operating efficiency,and could effectively solve the problems such as the difficulty in pesticides applying,labor shortage and low operating efficiency in the middle late growth stage of high stalk crops.This technology successfully opened up a simple,efficient and new way for the effective control of major sugarcane pests and diseases,and practically accelerated the process of integrated control and prevention of sugarcane pests and diseases.In addition,this technology had an extremely significant effect on reducing the loss of sugarcane farmers and enterprises caused by the epidemic and outbreak of sugarcane pests and diseases,increasing sugarcane yield and sugar content.At the same time,this technology played an important role in realizing the whole-process precise control of sugarcane pests and diseases,improving the quality and increasing the efficiency of sugarcane,and guaranteeing the national sugar safety.

Research Progress and Prospect of Sugarcane Smut

Sugarcane smut disease( Ustilago scitaminea Sydow) is an important fungal disease worldwide,which seriously affects yield and quality of sugarcane and threatens the stability and development of sugarcane industry. This paper reviewed disease occurrence,damage,pathogen,symptoms,genetic diversity and detection methods of sugarcane smut,response of sugarcane to sugarcane smut stress and control measures of sugarcane smut. The in-depth research of sugarcane smut was also prospected,aiming to provide theoretical reference and scientific basis for the effective control of sugarcane smut.

Control Effect of Slow-release, Long-acting and Multi-functional New Pesticides on Sugarcane Borders and Woolly Aphids

In order to select the long-acting,low toxic,low-risk and multi-functional new pesticides for the control of sugarcane borders and woolly aphids and precise and efficient application technology,the control effect of 10% monosultap · thiamethoxam granular formulation and 1% Bt · clothianidin granular formulation on sugarcane borders and woolly aphids were studied.The results showed that 10% monosultap·thiamethoxam GR and 1% Bt·clothianidin GR had good control effects on sugarcane borders and woolly aphids.They were ideal slow-release,long-acting,low toxic and multi-functional new pesticides used to control sugarcane borders and woolly aphids.They could be used alternately with other pesticides to delay the emergence and development of pest resistance to pesticides.The best dosage of the two pesticides in the field was 45 kg/hm^2.They could be mixed with fertilizer( 1200-1800 kg/hm^2),scattered in sugarcane ditches or at the base of sugarcane plants,and covered with soil or film from January to July.The control effect on dead heart seedlings damaged by borers could be up to above 79.2%,and the control effect on sugarcane woolly aphids could reach more than 98.8%.In comparison with the control group,the actual yield and sugar content of sugarcane increased by above 41 555 kg/hm^2 and 6.5% respectively.The application of slow-release,long-acting,strong systemic and multi-functional new agents with fertilizer around roots is convenient,precise and efficient,labor-saving,time-saving and environmentally friendly,and is worthy of being widely applied in sugarcane areas.

Control Effects of a New Sex Pheromone Trap and Biological Agents on Sesamia inferens Walker and Argyroploce schistaceana (Snellen)

This study was conducted to explore and seek high-efficiency and safe green control techniques on sugarcane borers,promote green control of diseases and pests of sugarcane and build a resource-conserving,environmentally friendly and sustainable governance system of diseases and pests of sugarcane.A new sex pheromone trap of sugarcane borers,abamectin· Bacillus thuringiensis (Bt) and tebufenozide were selected and applied in field trials.The use of the new sex pheromone trap of sugarcane borers (6 traps/hm 2) in combination with 0.05% abamectin·10 billion active gemmae/g B.thuringiensis (Bt) WP (1.8 kg/hm 2) or new sex pheromone trap of sugarcane borers (6 traps/hm 2) in combination with 200 g/L tebufenozide SC (1.5 L/hm 2) were the best in the sugarcane production.New sex pheromone trap of sugarcane borers should be installed in early march,and biological agents were mixed with water 900 kg per hectare and sprayed evenly sugarcane plants at the beginning of April.Their control effects of dead heart rate and bored stalk rate could be more than 69.98% and 49.09%,respectively,which were superior to that of the control pesticide 3.6% bisultap GR (90 kg/hm 2).The results showed that new sex pheromone trap of sugarcane borers in combination with abamectin· B.thuringiensis (Bt) or tebufenozide was the optimum mode of green control techniques on sugarcane borers.When it was alternately or coordinately used with other technology,it could delay the emergence and development of drug resistance,and it was worthy of widespread popularization and application in sugarcane area.

Dynamic Monitoring and Control Measures of Spodoptera frugiperda(J.E.Smmith) in Low Latitude Plateau Sugarcane Areas

Spodoptera frugiperda (J.E.Smmith) is one of the major migratory pests warned by the Food and Agriculture Organization (FAO).It has been successfully invaded sugarcane and corn in Jinggu,Longchuan,Gengma,Menghai,Yingjiang,Lancang of Yunan Province,China.In view of the great variety of hosts,wide range of habitats and strong migration ability,S.frugiperda has the potential of causing catastrophic threats to sugarcane production.In this paper,we made a systematic introduction to the morphological and biological characteristics of S.frugiperda,analyzed its occurrence situations and occurrence trends in Yunnan of China and other countries around the world,and proposed the control strategies and measures of ecological regulation and control,natural enemies protection and utilization,biological control,pesticide control and adults trapping based on the outbreak characteristics of S.frugiperda and the actual sugarcane production in low latitude plateau areas.

Integration and Application of Comprehensive Prevention and Control Technology for Sugarcane Borers in Low Latitude Plateau of China

Aimed at the difficult problem of prevention and control of disastrous sugarcane borers in low latitude plateau of China,this research systematically overcame the bottleneck of comprehensive prevention and control of sugarcane bores after 10 years of collaborative research,and formed a number of core product technologies,which promoted the green and high-quality development of the sugarcane industry and achieved the following innovative results.In this study,the species,population structure and damage characteristics of disastrous sugarcane borers in low latitude plateau were clarified for the first time,which provided a scientific basis for the formulation of technology and application of comprehensive prevention and control.The monitoring technology system and early warning monitoring network were constructed for the monitoring of borer population in low latitude plateau sugarcane area,which realized the accurate monitoring of the population dynamics of sugarcane bores and provided technical support for comprehensive prevention and control.The flight spraying technology by unmanned aerial vehicle(UAV)was developed for bores in the low latitude plateau cane area,and it has been successfully applied in a large area,thereby opening up a new way of light,simple and efficient for effective control of borers.The scale application of lamp trapping and sexual attracting to kill adult insects technology promoted the advancement of green control technology of bores.Integration was made to the comprehensive control techniques like UAV flight control,biological agents,physical and chemical inducement and control,and sexual attractant trapping in the low latitude plateau sugarcane area,and standardized technical regulations have been formulated,which significantly improved the overall prevention and control effect of large areas.The technologies for the comprehensive prevention and control of sugarcane borers have been popularized and applied in 8 major sugarcane producing states(cities)in low altitude plateau of Yunnan over the years,which has controlled the damage and showed remarkable control effect.In 2017-2018,the integrated control technology was popularized and applied to a total of 2.78×10^5 hm^2(1.33×10^4 hm^2 of UAV flight control)of area,which recovered a total of 3.666×10^6 t of sugarcane losses,increasing 4.69×10^5 t of sugar with the sales increase of 3.979 billion yuan,added profits of 1.251 billion yuan and the taxes increase of 188 million yuan.The research results show that the technology has high technical integration,strong practicability,high degree of transformation,significant economic,social and ecological benefits,which provide technical supports for the sustainable development,loss reduction and efficiency increase of the sugarcane industry in the low-latitude plateau sugarcane region,and make significant contributions to the economic development of ethnic minorities in the border-stricken areas and the increase of farmers income and poverty alleviation.

Research on Variation of Sugarcane Red Rot (Colletotrichum falcatum Went) and Sugarcane Disease Resistance

Sugarcane red rot caused by Colletotrichum falcatum Went is one of the important fungal diseases causing significant losses to sugarcane production,commonly known as "cancer" of sugarcane.It has risen from a minor disease to a major disease,resulting in the death of sugarcane in Lincang,Menglian and Shiping sugarcane areas in Yunnan Province.Due to the frequent variation of this pathogen,it is difficult to control,the pesticide control effect is not ideal at present,and there is still no effective and radical cure measures.The research on the variation of C.falcatum and sugarcane disease resistance is the only way to achieve the sustainable control of sugarcane disease.This paper mainly reviewed the genetic variation on the morphological,pathogenic and molecular variation of C.falcatum,and rapid molecular detection methods,and sugarcane disease resistance research in combination with the latest research at home and abroad.An outlook for further research on sugarcane red rot in the future was also given,to provide a theoretical basis for the research and control of sugarcane red rot in China.

Occurrence Dynamics and Control of 6 Sugarcane Pests with Potential Threats

In recent years,with the adjustment of agricultural structure,the change of planting system,the continuous cropping phenomenon and the abnormal climate and environment have provided favorable conditions for the spread,reproduction and survival of sugarcane pests.The pest species that are harmful to sugarcane have increased,which pose potential threats to sugar cane production.Therefore,the occurrence dynamics and control of 6 sugarcane pests with potential threats were studied in order to prospectively grasp the dynamics of sugarcane pests,scientifically and effectively prevent and control sugarcane pests,and ensure the safety of sugarcane production.

Detection and Identification of Sugarcane Pokkah Boeng Pathogens of Main Sugarcane Varieties in Yunnan Province

[Objectives]This study was conducted to identify the pathogen species and dominant species of sugarcane pokkah boeng in main varieties in Yunnan sugarcane areas,so as to promote the healthy and sustainable development of sugarcane industry.[Methods]Specific primers Fv-F3/Fv-R3 and Fp-F4/Fp-R4 were designed based on the ribosomal DNA non-internal transcribed spacer(rDNA-ITS)gene sequences of Fusarium verticillioides and Fusarium proliferarum,the main pathogens of sugarcane pokkah boeng,and 117 typical sugarcane pokkah boeng samples collected from main varieties in different sugarcane areas of Yunnan Province were detected and analyzed by PCR.[Results]Among the 117 sugarcane pokkah boeng samples,112 samples were detected with F.verticillioides with a positive detection rate of 95.7%;103 samples were detected with F.proliferarum with a positive detection rate of 88%;103 samples were infected by F.verticillioides+F.proliferarum,and the compound infection rate was 88%;and the two pathogens were not detected in 5 samples,which might be sugarcane pokkah boeng caused by other species.PCR amplification products of 23 F.verticillioides positive samples and 19 F.proliferarum positive samples from different sugarcane varieties in different sugarcane areas were sequenced.The BLAST alignment results showed that the sequences of the 23 amplification products of F.verticillioides shared 99.45%-100.00%homology with F.verticillioides(GenBank accession number:KU508286),and the sequences of the 19 amplification products of F.proliferarum shared 99.26%-100.00%homology with the sequence of F.proliferarum(GenBank accession number:MK252904).Part of the F.verticillioids and 11 F.proliferarum sequences were selected to construct a phylogenetic tree,and the phylogenetic analysis showed that they belonged to the F.verticillioids group and F.proliferarum group,respectively.The results showed that F.verticillioides and F.proliferarum were the main pathogens causing sugarcane pokkah boeng of the main sugarcane varieties in Yunnan,and there was a common phenomenon of compound infection.F.verticillioides was the dominant species in Pu er,Lincang,Honghe and Yuxi sugarcane areas,but the detection rate of F.proliferarum was also high,and there were other species.In the future,the discovery of resistant germplasm resources and breeding of resistant varieties should be carried out aiming at these two pathogens of sugarcane pokkah boeng.[Conclusions]The study provides technical support for rapid identification of sugarcane pokkah boeng pathogens,and scientific basis for breeding resistant varieties and scientific disease prevention and control.

Pathogen Identification and Phylogenetic Analysis of Sugarcane Rust in Plateau Areas at Low Latitudes

[Objectives]This study was conducted to clarify the species,occurrence and distribution characteristics of sugarcane rust pathogens in low-latitude plateau sugarcane rust areas of Yunnan Province and the phylogenetic relationship between the pathogens and that between them and other rust fungi of the genus Puccinia.[Methods]Fifty seven sugarcane rust samples collected from the sugarcane areas of Baoshan,Lincang,Menghai,Menglian,Ximeng,Lancang and Wenshan in Yunnan were subjected to molecular identification.[Results]The four sugarcane rust samples from Haiyin1 hao in Menghai,Yunnan Province belonged to orange rust of sugarcane,and the pathogen was Puccinia kuehnii Butler.;and other 53 samples of sugarcane rust belonged to brown rust of sugarcane,and the pathogen was Puccinia melanocephala Syd.et P.Syd.The rDNA sequences of other rust fungi from the genus Puccinia were downloaded from GenBank and used for the construction of an NJ tree for systematic evolution analysis together with the sequences obtained in this study.The results showed that the four P.kuehnii sequences obtained in this study were clustered with Puccinia polysora(GenBank accession number:GU058024)into one group,and they were close genetically;the 53 P.melanocephala sequences were clustered with P.nakanishikii(GenBank accession number:GU058002),P.rufipes(GenBank accession number:AJ296545),Aecidium deutziae(GenBank accession number:KU309317)and P.coronata(GenBank accession number:DQ354526)into one group,and they had a close genetic relationship;and the genetic relationship of the two species of sugarcane rust fungi identified in this study was relatively distant.[Conclusions]This study provides a scientific basis for sugarcane rust epidemic prediction,disease resistance breeding,and precise prevention and control.

Evaluation of the Effect of High-efficiency Compound Formulations on the Prevention and Control of Sugarcane Brown Stripe

[Objectives]This study was conducted to screen high-efficiency compound formulations and precise application technologies for the prevention and control of sugarcane brown stripe disease.[Methods]Carbendazim,benomyl,chlorothalonil,azoxystrobin,pyraclostrobine and difenoconazole·azoxystrobin were selected for field efficacy tests.[Results]Three formulations,(50%carbendazim WP 1500 g+75%chlorothalonil WP 1500 g+potassium dihydrogen phosphate 2400 g+agricultural synergist 300 ml)/hm^(2),(50%benomyl WP 1500 g+75%chlorothalonil WP 1500 g+potassium dihydrogen phosphate 2400 g+agricultural synergist 300 ml)/hm^(2) and(25%pyraclostrobin 600 ml+potassium dihydrogen phosphate 2400 g+agricultural synergist 300 ml)/hm^(2) had good control effects on sugarcane brown stripe disease,and showed disease index below 14.02 and control efficacy above 84.41%.The three formulations are ideal high-efficiency compound formulations for the prevention and control of sugarcane brown stripe disease.They can be sprayed manually and by unmanned aerial vehicles on the foliar surface from July to August,once every 7 to 10 d,continuously for 2 times.[Conclusions]This study provides new technical support for accurate and efficient prevention and control of sugarcane brown stripe disease.

Evaluation of the Effects of High-efficiency Compound Formulations on the Prevention and Control of Sugarcane Brown Rust

[Objectives]This study was conducted to screen high-efficiency compound formulations and precise application technologies for the prevention and control of sugarcane brown rust. [Methods] Zineb, dinconazole, mancozeb, azoxystrobin, pyraclostrobin, difenoconazole·azoxystrobin, chlorothalonil and carbendazim were selected for field efficacy tests. [Results] Four formulations,(65% zineb WP 1 500 g+75% chlorothalonil WP 1 500 g+potassium dihydrogen phosphate 2 400 g+agricultural synergist 300 ml)/hm^(2),(12.5% dinconazole WP 1 500 g +75% chlorothalonil WP 1 500 g+potassium dihydrogen phosphate 2 400 g+agricultural synergist 300 ml)/hm^(2),(80% mancozeb WP 1 500 g+75% chlorothalonil WP 1 500 g+potassium dihydrogen phosphate 2 400 g+agricultural synergist 300 ml)/hm^(2) and(30% difenoconazole·azoxystrobin SC 900 ml+potassium dihydrogen phosphate 2 400 g+agricultural synergist 300 ml) had good control efficacy on sugarcane brown rust, and showed disease indexes all below 18.79 and control efficacy over 80.53%. The four formulations are ideal high-efficiency compound formulations for the prevention and control of sugarcane brown rust. They can be sprayed manually and by unmanned aerial vehicles on the foliar surface from July to August, once every 7 to 10 d, continuously for 2 times. [Conclusions] This study provides new technical support for accurate and efficient prevention and control of sugarcane rust.