Seed and Root Exudations in Relation to Rhizoctonia Damping-off of Various Crops

Abstract

The relation between plant exudates and soil-borne diseases is a challenging problem in the field of plant pathology. Barton (1) and other workers (2,3,4,5,67,8,9,10,13,) indicated that exudates from roots or other plant parts are attractive to parasitic organisms, or inductive to a growth response of pathogens that aids the infection process. Schroth and Snyder (11) proved that amino acids and sugars of bean exudates favorably influenced germination and growth of chiamydospores of Fusarium solani f. phaseoli in soil. 植物根或其他部位之分泌物已被確認可引誘寄生性生物之發生，促進植物病原菌之生長，並有助於侵染之完成。木研究以19種對Rhizoctonia solani不同感病程度之作物，以濾紙法測定其種子和根分泌物中含有氨基酸類及低醣類之多寡和分沁部位，比較各種作物種子和限分泌物培養病原菌後對菌絲生長之影響，並與栽植各種作物後土壤內菌絲密度之實際增減情形對照觀察，以資進一步瞭解種子和根分泌物對各種作物發生Rhizoctionia腰折病之關係。