Nonhost resistance: Self-inflicted DNA damage by fungal DNase accumulation is a major factor in terminating fungal growth in the pea-Fusarium solani f.sp phaseoli interaction

作者：Hadwiger Lee A^*

来源：Physiological and Molecular Plant Pathology, 2015, 92: 79-87.

DOI：10.1016/j.pmpp.2015.08.003

• Nonhost resistance
• Fungal DNase
• DNA damage
• Phytoalexin
• PR genes
• Self-inhibition of spore germination
• Signaling
• Pea
• Fusarium
• Universal effector

Pea endocarp tissue generates a total nonhost resistance response against inappropriate pathogens such as the bean pathogen, Fusarium solani f. sp. phaseoli (Fsph) within 6 h. An array of plant components induced include: Pisatin (a phytoalexin), defensins, PR genes and hydrolytic enzymes in the non-host resistance response. This nonhost resistance response is similar but swifter than the responses induced by the compatible true pathogen, F. solani f. sp. pisi (Fspi). It was previously noted that a DNase released by both fungi is involved in induction of these resistance responses within pea endocarp tissue. This report demonstrates the cytological damage that occurs within nuclear DNA of both compatible and incompatible fungi when in contact with pea endocarp tissue and in the presence of DNase activity. The severity of damage to the bean pathogen exceeds that of the pea pathogen and requires only 2 h of contact with the pea tissue to develop. This accumulation of DNA damage is proposed to be the ultimate termination factor in this and other non-host resistance reactions. An updated DNase signaling scheme of the nonhost resistance of pea is presented.

• 出版日期2015-10