תפריט נגישות
ניגודיות עדינהניגודיות גבוהה
מונוכרום
הדגשת קישורים
חסימת אנימציה
פונט קריא
סגור
איפוס הגדרות נגישות
להורדת מודול נגישות חינם תפריט נגישותניגודיות עדינהניגודיות גבוההמונוכרוםהדגשת קישוריםחסימת אנימציהפונט קריאסגוראיפוס הגדרות נגישותלהורדת מודול נגישות חינםR. Perl-Treves
Plant responses to herbivore attacks are complex, and include a variety of defense mechanisms. This study was focused on the interaction of the broad mite Polyphagotarsonemus latus (Acari: Tarsonemidae) and cucumber plants. We examined the effect of broad mite (BM) on plant morphology and growth patterns by monitoring total plant height, number of and size of leaves and internodes, over a 4-week infestation period. BM caused a substantial effect on growth and development of cucumber, with a significant decrease in all parameters measured. An attempt was made to identify possible signaling pathways that mediate plant responses to BM. Using Northern analysis, we tested the expression of genes known to be a part of the defense signaling pathways: beta-glucanase (BGL2) is part of the salicylic acid (SA)-dependent pathway; LOXI and LOX2, two cucumber lipoxygenase isoforms, represent the jasmonic acid (JA) pathway. A member of the ACC oxidase family, ACO1, represents ethylene synthesis. We compared gene expression between plants infested with BM and two control groups: untreated plants and plants that were mechanically wounded. Results indicate that BGL2, LOXI and LOX2 are induced by mite feeding, increasing between 24 and 72 h post-infestation, and subsequently decreasing. Wounding did not induce these transcripts, except for a slight induction of LOX1. ACO1, on the other hand, shows a rather uniform expression pattern. These results suggest that BM causes an induction of both the SA and JA pathways. However, it is still not known whether this response is local or both local and systemic and how the ability of plants to express these defense pathways affects their susceptibility to BM. (P)
R. Perl-Treves
Plant responses to herbivore attacks are complex, and include a variety of defense mechanisms. This study was focused on the interaction of the broad mite Polyphagotarsonemus latus (Acari: Tarsonemidae) and cucumber plants. We examined the effect of broad mite (BM) on plant morphology and growth patterns by monitoring total plant height, number of and size of leaves and internodes, over a 4-week infestation period. BM caused a substantial effect on growth and development of cucumber, with a significant decrease in all parameters measured. An attempt was made to identify possible signaling pathways that mediate plant responses to BM. Using Northern analysis, we tested the expression of genes known to be a part of the defense signaling pathways: beta-glucanase (BGL2) is part of the salicylic acid (SA)-dependent pathway; LOXI and LOX2, two cucumber lipoxygenase isoforms, represent the jasmonic acid (JA) pathway. A member of the ACC oxidase family, ACO1, represents ethylene synthesis. We compared gene expression between plants infested with BM and two control groups: untreated plants and plants that were mechanically wounded. Results indicate that BGL2, LOXI and LOX2 are induced by mite feeding, increasing between 24 and 72 h post-infestation, and subsequently decreasing. Wounding did not induce these transcripts, except for a slight induction of LOX1. ACO1, on the other hand, shows a rather uniform expression pattern. These results suggest that BM causes an induction of both the SA and JA pathways. However, it is still not known whether this response is local or both local and systemic and how the ability of plants to express these defense pathways affects their susceptibility to BM. (P)
