生物诱导剂和杀菌剂对新疆红枣黑斑病抗性的影响

Effects of Biological Inducers and Fungicides on Black Spot Disease Resistance of Xinjiang Jujube

为筛选红枣黑斑病生物防控的有效药剂,以新疆红枣骏枣为供试对象进行田间试验,分别以生物诱导剂水杨酸(SA)、茉莉酸甲酯(MeJA)以及生物源杀菌剂木霉源纳米硒(TSNP)为供试药剂,戊唑醇(WZ)为对照化学杀菌剂,清水(CK)为空白对照,测定不同药剂处理红枣果实的自然发病率及采后红枣果实的营养品质指标,并测定枣果全红期接种链格孢菌(Alternaria alternata)后不同时间抗病相关酶活性和酶基因表达量。结果表明,MeJA和TSNP处理红枣果实对黑斑病的防效最好,发病率分别较CK降低76.16%和85.50%。药剂处理提高了采后枣果的部分营养品质,其中TSNP处理枣果氨基酸总量较CK提高0.59%,SA处理枣果果糖和葡萄糖含量分别提高16.73%和18.27%,WZ处理枣果葡萄糖含量提高19.38%,MeJA处理红枣果实中天门冬氨酸(Asp)和组氨酸(His)含量分别较CK提高13.81%和24.56%。药剂处理枣果接种链格孢菌后,抗病性相关酶活性也有所提高,其中,SA处理接种后第3天,超氧化物歧化酶(SOD)活性最高,是CK的6.56倍;TSNP处理接种后第5天,SOD活性最高,是CK的2.51倍,接种后第7天,多酚氧化酶(PPO)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)、苯丙氨酸解氨酶(PAL)活性分别是CK的14.00、1.37、1.37、1.10倍;MeJA处理接种后第7天,过氧化物酶(POD)、PPO活性分别是CK的1.14、13.75倍。与此同时,抗病相关酶基因表达量也发生变化,MeJA处理接种后第3天,枣果PAL基因相对表达量最高,比CK上调了63.19%,接种后第5天,CAT基因相对表达量比CK上调55.43%,接种后第7天,SOD基因相对表达量比CK上调了60.00%;TSNP处理接种后第3天,CAT基因相对表达量最高,比CK上调了72.45%,接种后第7天,PAL基因相对表达量最高,比CK上调了79.06%;SA处理接种后第5天,SOD基因相对表达量最高,比CK上调了36.96%。综上,不同生物诱导剂和杀菌剂对新疆红枣营养成分和抗病性有不同程度的影响,其中,MeJA和TSNP整体效果最佳,可以作为红枣黑斑病生物防控的有效药剂。

To select effective agents for the biological control of black spot disease,for Jun jujube(Zizyphus jujuba Mill.cv.Junzao)in Xinjiang,different inducers and fungicides were tested in this study.Among them,salicylic acid(SA) and methyl jasmonate(MeJA) belonged to biological inducers,Trichoderma harzianum-derived selenium nanoparticles(TSNP) belonged to biogenic fungicide,tebuconazole(WZ)was used as the contrast chemical fungicide and water was used as the blank control(CK).Black spot incidence rate and nutritional quality of jujube fruit after harvested in all the treatments were determined.The activity and gene expression of disease-resistance related enzymes were investigated at different time after being inoculated with Alternaria alternata.Results showed that MeJA and TSNP had the best control effect on black spot disease in jujube fruits,and the incidence rates were76.16% and 85.50% lower than CK,respectively.Inducers and fungicides treatments could improve the nutritional quality of jujube fruit to some extent,for example,the total amino acid content in TSNP treatment was increased by 0.59%,the fructose and glucose contents in SA treatment were increased by16.73% and 18.27%,respectively,the glucose content in WZ treatment was increased by 19.38%,and the contents of aspartate(Asp)and histidine(His)in MeJA treatment were increased by 13.81% and24.56%,respectively.The activities of disease-resistance related enzymes in jujube fruit in various agent treatments were also increased after being inoculated with Alternaria alternata at different days.On the3rd day after being inoculated,the activity of superoxide dismutase(SOD)in SA treatment was the highest,which was 6.56 times that in CK.On the 5th day after being inoculated,the activity of SOD in TSNP treatment was the highest,which was 2.51 times that in CK.And also in TSNP treatment,on the7th day after being inoculated,the activities of polyphenol oxidase(PPO),catalase(CAT),ascorbiate peroxidase(APX)and phenylalnine ammonialyase(PAL)were 14.00,1.37,1.37 and 1.10 times those in CK,respectively.In MeJA treatment,on the 7th day after being inoculated,the activities of peroxidase(POD)and PPO were 1.14 and 13.75 times those in CK,respectively.At the same time,the expression of disease-resistance related enzyme genes also changed.In MeJA treatment,the gene expression level of PAL was highest on the 3rd day,which was 63.19% higher than CK;the gene expression level of CAT was highest on the 5th day,which was 55.43% higher than CK;the gene expression level of SOD was highest on the 7th day,which was 60.00% higher than CK.In TSNP treatment,the gene expression of CAT was highest on the 3rd day,which was up-regulated by 72.45% compared with CK;and the gene expression of PAL was the highest on the 7th day,which was up-regulated by 79.06% compared with CK.In SA treatment,the SOD gene expression of jujube fruit was highest on the 5th day,which was up-regulated by 36.96% compared with CK.In conclusion,different biological inducers and fungicides have different influence on the nutritional composition and black spot disease resistance of Xinjiang jujube.Among them,MeJA and TSNP have the best overall effect,and could be used as effective agents for biological control of black spot disease.