More than 12,000 plant species(ca.10%of flowering plants)exude latex when their tissues are injured.Latex is produced and stored in specialized cells named“laticifers”.Laticifers form a tubing system composed of row...More than 12,000 plant species(ca.10%of flowering plants)exude latex when their tissues are injured.Latex is produced and stored in specialized cells named“laticifers”.Laticifers form a tubing system composed of rows of elongated cells that branch and create an internal network encompassing the entire plant.Laticifers constitute a recent evolutionary achievement in ecophysiological adaptation to specific natural environments;however,their fitness benefit to the plant still remains to be proven.The identification of Euphorbia lathyris mutants(pil mutants)deficient in laticifer cells or latex metabolism,and therefore compromised in latex production,allowed us to test the importance of laticifers in pest resistance.We provided genetic evidence indicating that laticifers represent a cellular adaptation for an essential defense strategy to fend off arthropod herbivores with different feeding habits,such as Spodoptera exigua and Tetranychus urticae.In marked contrast,we also discovered that a lack of laticifer cells causes complete resistance to the fungal pathogen Botrytis cinerea.Thereafter,a latex-derived factor required for conidia germination on the leaf surface was identified.This factor promoted disease susceptibility enhancement even in the non-latex-bearing plant Arabidopsis.We speculate on the role of laticifers in the coevolutionary arms race between plants and their enemies.展开更多
Predatory mites of the Phytoseiidae family are considered one of the most important groups of natural enemies used in biological control.The behavioral patterns of arthropods can differ greatly daily and seasonally;ho...Predatory mites of the Phytoseiidae family are considered one of the most important groups of natural enemies used in biological control.The behavioral patterns of arthropods can differ greatly daily and seasonally;however,there is a lack of literature related to Phytoseiidae diel and seasonal predation patterns.The predatory activity of three phytoseiid species (two Tetranychidae-specialists,Phytoseiuluspersimilis and Neoseiulus californicus,and one omnivore,Euseius stipulatus)that occur naturally in Spanish citrus orchards was observed under laboratory conditions in winter and summer.The temperature and photoperiod of the climatic chamber where the mites were reared did not change during the experiment.Our study demonstrates that phytoseiids can exhibit diel and seasonal predatory patterns when feeding on Tetranychus urticae (Acari:Tetranychidae).Neoseiulus californicus was revealed to be a nocturnal predator in summer but diurnal in winter.In contrast,P.persimilis activity was maximal during the daytime,and E.stipulatus showed no clear daily predation patterns.The predatory patterns described in this study should be taken into account when designing laboratory studies and also in field samplings,especially when applying molecular techniques to unveil trophic relationships.展开更多
基金supported by a grant from the Agencia Estatal de Investigaciòn(AEI),Spain(RTI2018-098501-B-I00).
文摘More than 12,000 plant species(ca.10%of flowering plants)exude latex when their tissues are injured.Latex is produced and stored in specialized cells named“laticifers”.Laticifers form a tubing system composed of rows of elongated cells that branch and create an internal network encompassing the entire plant.Laticifers constitute a recent evolutionary achievement in ecophysiological adaptation to specific natural environments;however,their fitness benefit to the plant still remains to be proven.The identification of Euphorbia lathyris mutants(pil mutants)deficient in laticifer cells or latex metabolism,and therefore compromised in latex production,allowed us to test the importance of laticifers in pest resistance.We provided genetic evidence indicating that laticifers represent a cellular adaptation for an essential defense strategy to fend off arthropod herbivores with different feeding habits,such as Spodoptera exigua and Tetranychus urticae.In marked contrast,we also discovered that a lack of laticifer cells causes complete resistance to the fungal pathogen Botrytis cinerea.Thereafter,a latex-derived factor required for conidia germination on the leaf surface was identified.This factor promoted disease susceptibility enhancement even in the non-latex-bearing plant Arabidopsis.We speculate on the role of laticifers in the coevolutionary arms race between plants and their enemies.
文摘Predatory mites of the Phytoseiidae family are considered one of the most important groups of natural enemies used in biological control.The behavioral patterns of arthropods can differ greatly daily and seasonally;however,there is a lack of literature related to Phytoseiidae diel and seasonal predation patterns.The predatory activity of three phytoseiid species (two Tetranychidae-specialists,Phytoseiuluspersimilis and Neoseiulus californicus,and one omnivore,Euseius stipulatus)that occur naturally in Spanish citrus orchards was observed under laboratory conditions in winter and summer.The temperature and photoperiod of the climatic chamber where the mites were reared did not change during the experiment.Our study demonstrates that phytoseiids can exhibit diel and seasonal predatory patterns when feeding on Tetranychus urticae (Acari:Tetranychidae).Neoseiulus californicus was revealed to be a nocturnal predator in summer but diurnal in winter.In contrast,P.persimilis activity was maximal during the daytime,and E.stipulatus showed no clear daily predation patterns.The predatory patterns described in this study should be taken into account when designing laboratory studies and also in field samplings,especially when applying molecular techniques to unveil trophic relationships.
