玉米种质对腐霉茎腐病和镰孢茎腐病抗性鉴定与评价

【目的】 系统评价新疆玉米种质资源对玉米茎腐病优势病原菌的抗性水平,为玉米抗茎腐病遗传育种及防治提供科学依据。【方法】 采用田间人工土壤埋接法,对62份玉米种质资源进行抗肿囊腐霉(P. inflatum)茎腐病水平鉴定,鉴定及评价100份玉米种质资源的抗镰孢茎腐病水平。【结果】 62份种质资源抗肿囊腐霉(P. inflatum)茎腐病达到高抗(HR)7份,占比11.29%,抗(R)、中抗(MR)、感(S)、高感(MS)材料分别为5份、18份、5份和27份,依次占比8%、29%、8%和24%。100份种质资源抗镰孢茎腐病鉴定与评价则筛选出高抗(HR)、抗(R)、中抗(MR)、感(S)、高感(MS)材料分别为14份、16份、37份、15份和18份。病株率与株高、穗长、穗粗呈极显著负相关,高杆穗粗的玉米品种具有良好的抗病基础。而干穗重、粒重、百粒重与病株率呈显著或极显著负相关,病株率对产量指标具有极大的影响。21KBL054抽雄期、吐丝期、散粉期受影响程度较小,分别推迟2、2和4 d,21KBL096受影响程度严重,抽雄期、吐丝期、散粉期则分别推迟13、12和8 d。21KBL058病株平均株高(224.80cm)、穗位(83.09 cm)较对照相比分别增长(22.15%、51.76%),而处于同一抗性水平的21KBL045病株平均株高、穗位为186.50和72.64 cm,较对照相比增幅仅为(-0.40%、3.04%)受影响程度较小。【结论】 筛选出21KBL096、21KBL030、21KBL033等优异抗病性且田间性状稳定的抗病品种。

Identification and Evaluation of Maize Germplasm Resistance to Pythium Stem Rot and Fusarium Stem Rot

【Objective】 To systematically evaluate the resistance level of Xinjiang maize germplasm resources to dominant pathogens of corn stalk rot in the hope of providing scientific basis for genetic breeding and scientific control of corn stalk rot resistance.【Methods】 The level of resistance to P. inflatum stem rot of 62 maize germplasm resources and 100 maize germplasm resources to Fusarium stem rot were identified and evaluated by field artificial soil embedding method.【Results】 In 2020, 62 maize germplasm resources were identified for resistance to P. inflatum stem rot by field artificial soil embedding method. Seven highly resistant materials were identified, accounting for 11.29%, and 5, 18, 5 and 27 resistant, moderately resistant, susceptible and highly susceptible materials accounted for 8%, 29%, 8% and 24%, respectively. In 2021, 100 maize germplasm resources were artificially inoculated with F. Verticillioides to identify and evaluate its resistance to fusarium stem rot. 14, 16, 37, 15 and 18 highly resistant, moderate resistant, susceptible and highly susceptible materials were screened out, respectively. In addition, the correlation coefficients between plant rate and plant height, ear length and ear diameter were -0.333^**, -0.388^** and -0.283^**, respectively, indicating that maize varieties with high stalk and ear thickness had a good basis for disease resistance. The correlation coefficients between dry ear weight, grain weight, 100 grain weight and the disease plant rate were -0.203^*, -0.222^*, -0.379^**, respectively, showing significant or extremely significant negative correlation, indicating that the disease plant rate had a great influence on the yield index. The analysis of the effect of stem rot on the field characters of different maize varieties showed that the tasseling stage, silking stage and powder dispersing stage of 21KBL054 were less affected and delayed by 2, 2 and 4 days respectively, while 21KBL096 was seriously affected, and the tasseling stage, silking stage and powder dispersing stage were delayed by 13, 12 and 8 days respectively. The average plant height and ear position of 21KBL058 strains were 224.80cm and 83.09cm, respectively, increased by 22.15% and 51.76% compared with the control. The average plant height and ear position of 21KBL045 strains at the same resistance level were 186.50cm and 72.64 cm, respectively, which increased only by -0.40% and 3.04% compared with the control.【Conclusion】 In conclusion, a number of disease-resistant varieties with excellent disease resistance and stable field characters are comprehensively screened, such as 21KBL096, 21KBL030 and 21KBL033.