普通小麦八个品种对赤霉病抗扩展性的双列杂交分析

本文用8个对赤霉病不同抗性的普通小麦双列杂交的试验结果,分析了病小穗数的配合力、遗传力、性状相关及扩展速度等。小麦对赤霉病的抗性主要是由基因加性效应所决定的,非加性效应虽有一定的影响,但不显著。抗赤霉病性的遗传力较低,受环境的影响较大。病小穗数与有效小穗数和小穗密度的表现型和基因型呈正相关,与株高、穗长、无效小穗数和穗粒数呈微弱负相关,对赤霉病抗性与上述性状在遗传上似无明显的关系。高感品种福龙选的潜育期最长(9.2天),高抗品种望水白的最短(5.3天),其余的差异不大(6.2～6.9天)。高抗品种的赤霉病扩展速度较慢,高感品种的较快。

A DIALLEL CROSS ANALYSIS OF SPREADING RESISTANCE TO SCAB (Gibberella zeae(Schw) Petch) WITH 8 VARIETIES OF WHEAT ( Triticum aestivum L.)

D Aiallel cress with 8 varieties of wheat (T.aestivum L.)which had different resistance to scab (Gibberella zeae (Schw.) Petch) was tested.Combining ability of diseased spikelets,eritability,correlations of characters and spreading rate of disease were analysed.There-cults showed that varietal resistance to scab was determined by additive effect of genes was.not very important.Heritability for scab resistant was rather low and affected by environ mental factors.It was also demonstrated that in number of diseased spikelets to effective spikelets and to spikelet density there existed positive correlation between phenotypeand genotype.There was weak negative correlation of phenotype and genotype between diseasedpikelet number and plant height,panicle lenght,noneffective spikelet number and grain number.There was significant correlation between the characters mentioned above and varie-tal resistance to scab.The incubation periods of the highly susceptible variety-Fulon Shen and highly resistant variety-Wan Shube were the longest and the shortest,respectively.The incubation periods of the other varieties were between 6.2 to 6.9 days.The sprading rates.of highly resistant varieties and highly susceptible varieties for scab were slower and faster respectively