Failure of haustorial development as a factor in slow growth and development of Puccinia hordei in partially resistant barley seedlings

摘要: Observations on six barley lines differing for partial resistance, at 44 h and 6·5 days after inoculation with Puccinia hordei, indicated that a proportion of colonies fail to form haustoria, the failing being related level resistance. Following formation first hauslorium, rate further haustoria was reduced some time in high levels Failed haustorium quantified by determining number induced papillae. When reach certain size, host-colony interaction appears change abruptly towards compatibility, since hyphae formed from then induce fewer papillae than before. Indications were found differences resistance between epidermal mesophyll cells. Differences size phase development both within connected degree wall appositions (papillae formation) around point entry into leaf. The results are likely have importance understanding mechanisms determine basic compatibility.