Characterization and screening of cotton(Gossypium hirsutum L.)germplasm for leafhopper(Amrasca biguttula biguttula(Ishida))resistance

Background Cotton(Gossypium hirsutum L.)is one of the most significant fibre and cash crops and plays an important role in Indian industrial and agricultural economies.However,over the years quantity and quality have been hampered by the pest leafhopper.Leafhopper alone has been shown to cause yield losses of up to 40%.In this study,screening and evaluation were performed to identify and categorize 100 cotton genotypes along with 5 checks as resistant,moderately resistant,sensitive and highly sensitive to leafhoppers.Results A total of hundred genotypes were evaluated along with five checks for leafhopper resistance.Based on the screening results,a total of 19 genotypes were resistant to leafhoppers,which was on par with the findings of the check KC 3.The contents of total soluble sugar,total soluble protein,and total free amino acids were significantly positively correlated with the mean grade,whereas total phenols content and trichome density were significantly negatively correlated with the susceptibility grade.However,based on screening and biochemical analysis,the genotypes KC 2,JR-23,Samaru-26-T,D 4,TCH 1728,RS 253,and B-61-1862 exhibited high resistance to leafhopper.Conclusion According to the findings of this study,choosing genotypes with high total phenolics content together with high trichome density and low contents of total soluble sugar,total soluble protein,and free amino acids may aid in the development of resistant genotypes.

Screening of drought resistance indices and evaluation of drought resistance in cotton(Gossypium hirsutum L.)

Sixteen cotton cultivars widely planted in China were sowed under five different drought concentrations(0,2.5,5,7.5,and 10%)using PEG6000 to screen the indices of drought resistance identification and explore the drought resistance of different cotton cultivars.Eighteen physiological indices including root,stem,and leaf water contents(RWC,SWC,and LWC),net photosynthetic rate(Pn),the maximum photochemical quantum yield(Fv/Fm),the actual photochemical quantum yield(ΦPSII),non-photochemical quenching coefficient(NPQ),leaf water potential(LWP),osmotic potential(Ψs),leaf relative conductivity(REC),leaf proline content(Pro),leaf and root soluble protein contents(LSPC and RSPC),leaf and root malondialdehyde(MDA)contents(LMDA and RMDA),root superoxide dismutase,peroxidase,and catalase activities(RSOD,RPOD,and RCAT)were measured.Results indicated the 18 physiological indices can be converted into five or six independent comprehensive indices by principal component analysis,and nine typical indices(Fv/Fm,SWC,LWP,Pro,LMDA,RSPC,RMDA,RSOD,and RCAT)screened out by a stepwise regression method could be utilized to evaluate the drought resistance.Moreover,the 16 cotton cultivars were divided into four types:drought sensitive,drought weak sensitive,moderate drought resistant,and drought resistant types.The resistance ability of two selected cotton cultivars(drought resistant cultivar,Dexiamian 1;drought sensitive cultivar,Yuzaomian 9110)with contrasting drought sensitivities were further verified by pot experiment.Results showed that the responses of final cotton biomass,yield,and yield composition to drought were significantly different between the two cultivars.In conclusion,drought resistant cultivar Dexiamian 1 and drought sensitive cultivar Yuzaomian 9110 were screened through hydroponics experiment,which can be used as ideal experimental materials to study the mechanism of different cotton cultivars with contrasting drought sensitivities in response to drought stress.

Differential Expression of Whitebacked Planthopper Resistance in the japonica/indica Doubled Haploid Rice Population under Field Evaluation and Seedbox Screening Test

Whitebacked planthopper (WBPH) -resistance in a japonica / indica doubled haploid (DH) rice population established from a cross between WBPH-resistant japonica Chun]iang 06 and susceptible indica TN1, was comparatively evaluated through a field experiment based on the WBPH immigrant density and standardized seedbox screening test (SSST). All the susceptible DH lines in the field experiment behaved accordingly in SSST. However, 35 of resistant 66 lines (53%) in the field, were categorized to susceptible groups in SSST. Likewise, there were no significant differences in WBPH immigrant densities among 70 DH lines that were highly resistant to susceptible in SSST. The results revealed that SSST could not evaluate properly WBPH resistance in the DH lines. Four QTLs for WBPH-resistance phenotyped by the immigrant density were detected on chromosomes 2, 3, 4, and 11. Of them, the QTL on chromosome 4 was the most effective (LOD 21.8, variance 78%). Five QTLs associated with seedling mortality were mapped on chromosomes 2, 3, 4, 5 and 6. In addition to the QTL (LOD 10.5, variance 68%) on chromosome 4, there was another major QTL (LOD 12.7, variance 71%) located on chromosome 5, which was SSST-specific but might be irrespective of the WBPH resistance traits.

Generation of a series of mutant lines resistant to imidazolinone by screening an EMS-based mutant library in common wheat

The breeding of herbicide-resistant wheat varieties has helped control weeds in wheat fields economically and effectively.Imidazolinone (IMI) herbicides are popular as they have low toxicity in mammals,are effective at small doses,and exhibit broad-spectrum herbicidal action in the field.Therefore,the isolation and genetic and molecular characterization of IMI-resistant wheat mutants will enhance weed management in wheat fields.In the present study,352 IMI-resistant plants were isolated by genetic screening from a mutant pool prepared by EMS-based random mutagenesis.Cloning of the mutated genes from the IMI-resistant plants indicated that ten taals alleles had been isolated,and mutation in one of three Ta ALS homolog genes conferred IMI resistance,and such a mutation is a dominant trait.Further analysis showed that taals-d exhibited the greatest IMI resistance,whereas taals-b exhibited the weakest resistance to IMI among three homologous taals mutants.In terms of IMI resistance,the taals triple mutant was stronger than the taals double mutants,and the taals double mutants were stronger than the single mutants,indicating a dose-dependent effect of the Ta ALS mutation on IMI resistance in wheat.Biochemical analysis indicated that the mutation in Ta ALS increased the tolerance of Ta ALS to inhibition by IMI.Our work details the genetic and molecular characterization of als wheat mutants,provides a foundation for understanding IMI resistance and breeding wheat varieties with herbicide resistance,and indicates that genetic screening using a mutagenized pool is an effective and important means of breeding crops with additional desired agricultural traits.

In vitro Screening of Fusarium Wilt-resistant Germplasm Resources of Red Edible Seed Watermelon( Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao)

[ Objective] This study aimed to establish an appropriate technology system for in vitro screening of Fuzarium wilt-resistant germplasm resources of red edible seed watermelon and obtain variants resistant to fusaric acid, thus providing resistant materials for breeding Fusarium wilt-resistant red edible seed watermel- on. [ Method] Using Zhongxin No. 1 red edible seed watermelon advemitious buds as screening materials and fusaric acid （FA） as a stress agent, in vitro screen- ing of Fusarium wilt-resistant red edible seed watermelon clonal variants and identification of Fusarium wilt-resistance of the germplasm resources of red edible seed watermelon were performed. [ Result] The results showed that the appropriate FA for in vitro screening of Fusarium wilt-resistant red edible seed watermelon vari- ants was 15 mg/L. In vitro screening system for Fusarium wilt-resistant red edible seed watermelon variants was established preliminarily and FA-resistant regenera- ted plants were obtained. Among the 36 germplasm resources of red edible seed watermelon, there were 2 highly resistant materials, 6 moderately resistant materi- als, 11 slightly resistant materials and 17 highly susceptible materials. [ Conclusion] This study confirmed preliminarily that in vitro screening method is effective for obtaining resistant materials of red edible seed watermelon.

Screening of Tomato Resources Resistant to Tomato Gray Mold

This study was conducted to screen tomato resources resistant to gray mold for the first time by in-vitro stem inoculation method.The results showed that Solanum habrochaites T2-07-316 was highly resistant to gray mold,and had the relative stem infection rate and relative stem rot expansion rate of 0 on the 6^(th) day after inoculation.There were also other seven transgenic common tomato materials which showed higher resistance to gray mold,with a relative stem infection rate in the range of 15.00%-38.33% and a relative stem rot expansion rate in the range of 10.22%-23.57%.Among them,T2-07-337 had the best resistance.

Field Screening of Lesotho and South African Wheat Cultivars for Russian Wheat Aphid Resistance

Russian wheat aphid (Diuraphis noxia) is an international wheat pest and was first recorded in South Africa in 1978 in the Bethlehem area in the Eastern Free State. Le-sotho lies adjacent to one of the largest wheat producing areas in South Africa, the Eastern Free State, where winter wheat and facultative types are cultivated under dry land conditions. Wheat (Triticum aestivum L.) is an important crop adapted to all agro-ecological zones of Lesotho. Russian wheat aphid may have a significant impact on wheat yield. No monitoring or pest control is being done in Lesotho and at this stage there is very little information on the Russian wheat aphid resistance of wheat culti-vars cultivated in Lesotho. In view of this it is important to monitor the distribution of Russian wheat aphid biotypes in Lesotho and determine the level of Russian wheat aphid resistance in local Lesotho wheat cultivars. Two local Lesotho wheat cultivars, Bolane and Makalaote were screened together with South African cultivars Elands, Matlabas, Senqu, PAN3379, PAN3118 and SST387, in the glasshouse against all four known biotypes that occur in South Africa. All these cultivars were also planted in 5 m plots in the field at two localities Leribe and Roma in the lowlands of Lesotho. These cultivars were screened in the field for Russian wheat aphid resistance. The predomi-nant Russian wheat aphid biotypes in these areas were also determined. The Lesotho cultivar, Bolane had resistance against RWASA2 in the glasshouse, while Makalaote did not have any Russian wheat aphid resistance in either the glasshouse or field screenings. To contribute to food security an increasing wheat yield potential is a high priority. Russian wheat aphid has been included in the list of important international cereal pests. Russian wheat aphid adapts to changing environments and taking their ecology, distribution, virulence patterns, and variability into account is important in minimizing the gap between actual and attainable yields. Current management prac-tices for winter wheat in South Africa include the use of resistant cultivars, which is the most economical management strategy for Russian wheat aphid. Introducing Russian wheat aphid resistant cultivars in Lesotho will improve overall yield and as a result food security. This will also result in lower Russian wheat aphid pest pressure in the adjacent wheat production areas in the Eastern Free State, South Africa.

Cassava Anthracnose Disease and Varietal Screening for Resistance in Akwa Ibom State of Nigeria

Cassava （Manihot esculenta Crantz） production in Akwa Ibom State is limited by cassava anthracnose disease （CAD） which causes enormous losses in planting materials. Survey of the disease was conducted in the wet and dry seasons in six major cassava-growing areas （Essien Udim, Ikono, Itu, Nsit Atai, Oruk Anam and Uyo） of the State to determine the incidence and severity of the disease. Ten commonly grown cassava varieties were then screened in the greenhouse by inoculating each variety with the spore suspension of virulent isolate of the cassava anthracnose pathogen. Disease severity was assessed using size of lesions on the inoculated plants and defoliation caused by the infection. Results of the survey showed that Nsit Atai is a high infection area for CAD. It recorded the highest disease incidence and severity in both the wet season （36.59% and 3.52） and dry season （9.26% and 2.20）, respectively. The mean disease incidence （24.10%） and severity （3.23） for the six study areas were higher in the wet season indicating the importance of this season in the occurrence of CAD. Results of the screening test showed that TMS 98/30572 was resistant to the disease. The small lesion size （5.00 mm） observed in this variety would ensure less stem disruption and timely delivery of resources to the actively growing points. The low defoliation （5,65%） observed in the same variety would enhance the photosynthetic capacity of the plant. Therefore, TMS 98/30572 may be recommended to cassava farmers in Akwa Ibom State.

Screening and evaluation for soybean resistance to Phakopsora pachyrhyzi in Glycine soja

Soybean rust caused by Phakopsora pachyrhizy is an important disease of soybean, and yield losses are very common in humid growing regions. Most commercial cultivars are susceptible and the disease is usually managed with fungicides. Resistance breeding is the most effective in controlling the disease. In this study, detached - leaf assay and greenhouse inoculation were used to screen 200 Glycine soja accessions for resistance to Phakopsora pachyrhizi in China. Most of the accessions were susceptible, and W8214 was the only accession that demonstrated RB resistance to Phakopsora pachyrhizy. The further repeated tests confirmed the resistance in W8214.

基于大数据挖掘下多重耐药菌风险评估的研究价值

目的 基于大数据构建多重耐药菌感染的风险预测模型,并对其应用价值进行评估。方法 收集2018年1月至2022年12月于新疆医科大学第五附属医院诊治的405例患者,根据是否发生多重耐药菌(multidrug-resistant organisms,MDRO)感染分为非MDRO组(n=324)和MDRO组(n=81),比较并分析各指标与MDRO发生风险的相关性。构建大数据风险预测模型,分析各指标重要性,验证其准确性。结果 MDRO组合并糖尿病、原发肺部感染的患者比例,机械通气、广谱抗菌药物使用时间及降钙素原水平显著高于非MDRO组,而血红蛋白、白蛋白水平显著低于非MDRO组(均P <0.05);相关性分析显示,合并糖尿病、原发肺部感染等因素与MDRO风险的相关性较高,且合并糖尿病与原发肺部感染及联合使用抗生素等指标间相关性较高;大数据模型示抗生素使用时间、吞咽功能障碍等因素重要性较高,而血红蛋白及白蛋白重要性较低;大数据模型预测MDRO发生风险的AUC显著高于Logistic回归模型(Z=2.415,P=0.016),两种预测模型的训练集预测准确率差异无统计学意义(P>0.05);但测试集大数据模型预测准确率、敏感度及特异度均显著高于Logistic回归模型(χ^(2)=9.062,5.385,4.267;均P<0.05)。结论 合并糖尿病、原发肺部感染及联合使用抗生素等因素与MDRO发生风险具有一定相关性,基于MDRO危险因素指标的大数据模型对MDRO发生风险具有较高预测价值。

水稻品种恶苗病抗性评价与筛选

为了探讨黑龙江省南部稻区水稻品种对恶苗病的抗性级别及水稻恶苗病田间发病情况,筛选水稻恶苗病抗性品种,采用芽期人工接种的方法,调查分析了60份常规粳稻田间恶苗病发病率。结果表明:不同水稻品种恶苗病田间发生程度不同,水稻恶苗病发病率范围为0.8%~39.9%,平均发病率14.6%,筛选到1个高抗水稻品种,26个抗性水稻品种,抗性品种共占73.3%,总体抗感比为11:4,黑龙江省南部水稻品种对恶苗病抗性存在品种间差异,生产上应该提倡种植抗性强的品种以防止病害发生,本研究为病害绿色防控以及水稻恶苗抗病育种提供一定依据。

成人肠道CRE定植病例医院感染发病率的Meta分析

目的系统评价成人肠道耐碳青霉烯类肠杆菌目细菌(CRE)定植病例医院感染发病率,为CRE医院感染的预防和控制提供参考依据。方法计算机检索Embase、Cochrane、PubMed、Web of Science、CNKI、万方、维普、中国生物医学文献数据库(CBM)8个数据库自建库至2023年6月CRE肠道定植病例医院感染发病率的相关文献,应用Stata 17.0软件进行Meta分析,采用敏感性分析评价研究结果的稳定性,采用Egger’s检验评价发表偏倚。结果共纳入16篇文献,其中英文11篇,中文5篇,总样本量2151例患者。Meta分析结果显示,成人肠道CRE定植病例医院感染发病率为23.1%(95%CI:14.8%~32.5%)。以不同研究设计类型、发表年份,以及研究调查的地域、科室和感染部位分组因素进行亚组分析,亚组间的合并效应量比较,差异均无统计学意义(均P>0.05)。在CRE定植发展为医院感染中,耐碳青霉烯类肺炎克雷伯菌(CRKP)占比96.0%(95%CI:86.8%~100%),定植病例中血流感染发病率为18.2%(95%CI:10.3%~27.6%)。CRE定植病例30天病死率为32.6%(95%CI:20.5%~45.9%),CRE感染病例30天病死率为36.9%(95%CI:16.0%~60.2%)。结论近年来CRE定植病例医院感染发病率较高,需对高危科室进行主动筛查和重点干预,以降低CRE定植病例医院感染发病率。

杨叶枯病病原菌生物学特性、防治药剂筛选及杨树抗病性评价

为防治杨树叶枯病,利用单因素试验,对中荷64杨(P.×euramericana cv.‘N3016’)上分离获得的链格孢菌(Alternaria alternata)进行了生物学特性及室内防治药剂筛选研究,并开展了不同品种杨树抗叶枯病综合评价。结果表明:链格孢菌菌丝生长的适宜培养基为马铃薯蔗糖琼脂培养基,适宜碳源为玉米粉,适宜氮源为酵母提取物,适宜培养温度范围为25~30℃,适宜pH为8,光照条件对菌丝生长影响不大,致死温度为52℃。采用生长速率法进行室内防治药剂筛选,结果显示,选用的5种生物制剂防治效果优于2种化学药剂,各药剂抑制作用排序从大到小依次为哈茨木霉(3亿菌落/g)、枯草芽孢杆菌(100亿芽孢/g)、质量分数为10%的多抗霉素、质量分数为3%的中生菌素、质量分数为2%的宁南霉素、质量分数为50%的多菌灵、质量分数为75%的百菌清,将哈茨木霉(3亿菌落/g)和枯草芽孢杆菌(100亿芽孢/g)作为防治链格孢菌的适宜药剂。选用7个黑杨派品种杨树,利用模糊数学隶属度函数法,开展了杨树抗叶枯病综合评价,确定中荷64杨为高感品种,中辽1号杨和欧美杨177为中感品种,渤丰1号杨、渤丰3号杨、辽育3号杨和欧美杨111为高抗品种。

36份藜麦种质资源苗期耐盐碱性评价与筛选

为探究不同藜麦种质苗期耐盐碱性差异,本研究对36份藜麦种质苗期用150 mmol/L盐碱浓度(NaCl∶NaHCO_(3)=4∶1)进行胁迫处理,对株高、叶面积和叶片相对含水量等11个指标进行了测定,采用主成分分析等多种统计方法,筛选出适宜山西地区生长的藜麦种质。结果表明,盐碱胁迫下,藜麦种质各类指标相互之间均存在一定程度的关联;本试验中共提取5个主成分因子,方差累积贡献率为74.947%,可以代替11个指标的绝大部分信息,显示盐碱胁迫下藜麦苗期的抗盐碱特性,并且计算出耐盐碱性综合评价D值,并基于D值进行聚类分析,将36份种质资源分为四个大类,包括高耐盐碱种质5份、耐盐碱种质14份、弱耐盐种质11份、盐碱敏感种质共6份。

耐寒、抗旱、优质中晚熟甘蓝品种筛选试验

为筛选出适宜在六盘山区种植的耐寒、抗旱的优质甘蓝品种,对13个甘蓝品种开展了比较试验,结果表明:所有参试品种均未发生抽薹开花和茎秆升高现象,圆球型甘蓝品种京甘103在品质方面除硝酸盐含量较高外,其他品质表现优异,可溶性固形物含量、可溶性糖含量、净菜率分别达9.17%、5.92%、65.07%,均显著高于其他圆球型甘蓝品种,MDA(丙二醛)含量较低,为0.43μmol/g,虽然产量低,但品质较优、口感脆嫩、外形美观,深受消费者喜欢;平头型甘蓝品种中甘107生长势强,不易裂球,可溶性糖含量、维生素C含量高,分别达5.32%、9.68 mg/kg,显著高于其他平头型甘蓝品种,且MDA和POD(过氧化物酶)含量较低,SOD(超氧化物歧化酶)和CAT(过氧化氢酶)的活性较高,整体抗逆性优于其他品种;平头型甘蓝品种晚丰光合能力较强,SPAD值最高为60.18,显著高于其他圆球型甘蓝品种,抗病性强,可溶性固形物、净菜率、脯氨酸含量高,分别为9.2%、61.14%、0.123%,667 m^(2)产量最高,为3518.43 kg。综上所述,京甘103、中甘107和晚丰适宜在六盘山区大面积示范推广种植。虽然紫甘蓝欧梅罗和普来米罗的长势较其他品种差,但是品质优异,营养价值高,可作为鲜食品种进行推广种植。

Evaluation and screening for resistance of some varieties(lines)to major diseases and insect pests of rice

During 1984-1988,2,231 varieties(lines)from International Rice Testing Program(IRTP)were evaluated and screened for resistance to riceblast(Bl),bacterial blight(BB),sheath blight

抗黄曲霉侵染与产毒的花生品种筛选

花生是我国重要的经济作物和油料作物,易被黄曲霉侵染。黄曲霉产生的黄曲霉毒素具有强毒性和强致癌性,严重威胁花生食品安全和人体健康,不利于花生产业健康发展。为了筛选抗黄曲霉侵染与产毒的花生品种,本研究采用孢子菌悬液侵染法,以37个花生品种的籽仁为试验材料,利用黄曲霉侵染指数和黄曲霉毒素B_(1)(AFB_(1))含量分析比较各品种的抗侵染性。结果显示,37个花生品种籽仁的黄曲霉侵染指数分布范围为11.00%~80.33%,筛选出中抗黄曲霉侵染品种13个,中感黄曲霉侵染品种19个,感黄曲霉侵染品种4个和高感黄曲霉侵染品种1个,未筛选出高抗品种。AFB_(1)检测结果表明,黄曲霉毒素B_(1)含量最低的3个花生品种为花育23号、花育616和花育9121。相关性分析结果表明黄曲霉侵染指数与AFB_(1)含量呈显著正相关。

羊肉中腐败菌的分离鉴定及致腐能力研究

为筛选腐败能力强的菌株,本研究从托盘和真空包装羊肉4℃贮藏期间的均质液中分离腐败菌并对其进行鉴定,利用羊肉汁、脱脂牛奶和三丁酸甘油酯3种培养基评估分离菌株在体外对羊肉、蛋白质和脂质的降解能力,从而确定目标菌株并进一步分析其耐药基因图谱。结果表明,托盘包装中共纯化出191株菌株,主要菌属包括假单胞菌、不动杆菌和寡养单胞菌;真空包装中共纯化出72株菌株,主要菌属包括乳杆菌、乳球菌、肉杆菌、沙雷氏菌和哈夫尼亚菌。根据体外腐败能力测定结果,从每种包装中确定3株菌株作为后续研究的目标菌株,并根据基因组相似性计算结果确定种名,托盘包装中的目标菌株为MN10(副乳假单胞菌)、MN21(不动杆菌新菌种)和EF8(嗜麦芽窄食单胞菌),真空包装中的目标菌株为VMR17(清酒乳杆菌)、VF12(变形斑沙雷氏菌)和VE13(变形哈夫尼亚菌)。耐药性基因结果表明,含量较高的抗生素基因为大环内酯类抗生素、四环素类抗生素、氟喹诺酮抗生素、吖啶染料、亚胺培南类抗生素和氨基糖苷类抗生素。该研究为后续生鲜肉的靶向抑菌和腐败菌的腐败机理探究提供了研究基础。

基于压裂力筛选油菜抗裂角优异种质资源

油菜成熟后角果易开裂,导致收获损失率高,限制了产业的高质量发展。筛选抗裂角优异种质资源,对于培育抗裂角宜机收的油菜新品种具有重要意义。为了提高油菜抗裂角资源的筛选效率,本研究基于200份变异丰富的甘蓝型油菜种质资源,系统比较压裂法与随机碰撞法的鉴定结果,提出了一种基于压裂力的抗裂角高效鉴定方法。研究发现,基于随机碰撞法的抗裂角指数与基于压裂法的裂角力之间显著正相关,且压裂法比随机碰撞法重复性更好、效率更高、稳定性更强。基于抗裂角指数和裂角力之间的相关关系,制定了基于压裂力的抗性分级标准,最终基于压裂力筛选出5份高抗裂角的甘蓝型油菜优异种质资源。相关结果为进一步培育优质的油菜抗裂种质资源提供了高效的鉴定方法和重要的基因资源。

甜瓜抗枯萎病资源筛选及抗病生理指标相关性分析

为明确黑龙江地区甜瓜枯萎病生理小种,探究枯萎病胁迫下甜瓜生理指标变化,完善甜瓜枯萎病抗病评价体系,利用表型鉴定结合分子标记辅助选择(MAS,marker-assisted selection)对24份甜瓜资源进行抗病筛选。结果表明,黑龙江省尖孢镰刀菌甜瓜专化型Fm-1为1号生理小种。分子标记辅助选择共筛选出抗病资源15份,感病资源9份,具有较高的筛选效率。其中野生型资源1314抗性最强,发病率仅为10%;栽培种22-152的感病程度最高。利用筛选的两个抗性极端材料在幼苗期接种病原菌并于根部取样,测定抗病生理指标并进行相关性分析。结果表明,枯萎病胁迫下的抗病和感病材料生理指标响应差异显著,过氧化氢酶(CAT)、苯丙氨酸解氨酶(PAL)、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性与发病率呈极显著负相关;丙二醛含量和相对电导率与发病率呈极显著正相关。综上,利用功能性分子标记可在早期实现精准筛选甜瓜抗枯萎病品种,相对电导率和CAT及PAL活性可作为抗枯萎病评价的首选指标。