Presentation Type

Poster

Keywords

resin, Rhus ovata, dieback, drought, resin production, chaparral, Santa Monica Mountains

Department

Biology

Major

Biology

Abstract

Resin production in stems of woody plants is generated from resin canal secretions and is thought to play a significant role in protection from fungal infection and spread. This may be one of several factors associated with fungal infection and fungal induced dieback in plants during severe water stress or drought. We set out to determine if reduction in resin production in a chaparral shrub, Sugar Bush (Rhus ovata), was associated with severe drought in southern California. We hypothesized that dehydrated R. ovata would produce less resin than hydrated plants. Our null hypothesis was that there is no significant difference in resin production between dehydrated and hydrated plants. We designated two study sites to test this, one hydrated and one dehydrated, and used a Scholander-Hammel Pressure Chamber to measure both water potential of stem tissue and to collect xylem resin in vials weighted on an analytical balance to estimate resin production. Results showed greater resin production in hydrated stems at predawn than in dehydrated stems. The same trend held at midday but was not significantly different between hydrated and dehydrated plants. Through this research, we were able to determine one of the ways water stress affects R. ovata, and that the reduction in the amount of resin duct flow is a direct result of the drought the plants have been experiencing over the past few years in the Santa Monica Mountains. As California’s climate changes to become drier and hotter, it is likely that native species will produce less resin during summer drought and thus be less protected from the infection and spread of fungal disease.

Resin production in stems of woody plants is generated from resin canal secretions and is thought to play a significant role in protection from fungal infection and spread. This may be one of several factors associated with fungal infection and fungal induced dieback in plants during severe water stress or drought. We set out to determine if reduction in resin production in a chaparral shrub, Sugar Bush (Rhus ovata), was associated with severe drought in southern California. We hypothesized that dehydrated R. ovata would produce less resin than hydrated plants. Our null hypothesis was that there is no significant difference in resin production between dehydrated and hydrated plants. We designated two study sites to test this, one hydrated and one dehydrated, and used a Scholander-Hammel Pressure Chamber to measure both water potential of stem tissue and to collect xylem resin in vials weighted on an analytical balance to estimate resin production. Results showed greater resin production in hydrated stems at predawn than in dehydrated stems. The same trend held at midday but was not significantly different between hydrated and dehydrated plants. Through this research, we were able to determine one of the ways water stress affects R. ovata, and that the reduction in the amount of resin duct flow is a direct result of the drought the plants have been experiencing over the past few years in the Santa Monica Mountains. As California’s climate changes to become drier and hotter, it is likely that native species will produce less resin during summer drought and thus be less protected from the infection and spread of fungal disease.

Faculty Mentor

Stephen Davis

Location

Waves Cafeteria

Start Date

24-3-2017 2:00 PM

End Date

24-3-2017 3:00 PM

Share

COinS
 
Mar 24th, 2:00 PM Mar 24th, 3:00 PM

Effect of Drought on Resin Production in Woody Stems of Rhus ovata

Waves Cafeteria

Resin production in stems of woody plants is generated from resin canal secretions and is thought to play a significant role in protection from fungal infection and spread. This may be one of several factors associated with fungal infection and fungal induced dieback in plants during severe water stress or drought. We set out to determine if reduction in resin production in a chaparral shrub, Sugar Bush (Rhus ovata), was associated with severe drought in southern California. We hypothesized that dehydrated R. ovata would produce less resin than hydrated plants. Our null hypothesis was that there is no significant difference in resin production between dehydrated and hydrated plants. We designated two study sites to test this, one hydrated and one dehydrated, and used a Scholander-Hammel Pressure Chamber to measure both water potential of stem tissue and to collect xylem resin in vials weighted on an analytical balance to estimate resin production. Results showed greater resin production in hydrated stems at predawn than in dehydrated stems. The same trend held at midday but was not significantly different between hydrated and dehydrated plants. Through this research, we were able to determine one of the ways water stress affects R. ovata, and that the reduction in the amount of resin duct flow is a direct result of the drought the plants have been experiencing over the past few years in the Santa Monica Mountains. As California’s climate changes to become drier and hotter, it is likely that native species will produce less resin during summer drought and thus be less protected from the infection and spread of fungal disease.

Resin production in stems of woody plants is generated from resin canal secretions and is thought to play a significant role in protection from fungal infection and spread. This may be one of several factors associated with fungal infection and fungal induced dieback in plants during severe water stress or drought. We set out to determine if reduction in resin production in a chaparral shrub, Sugar Bush (Rhus ovata), was associated with severe drought in southern California. We hypothesized that dehydrated R. ovata would produce less resin than hydrated plants. Our null hypothesis was that there is no significant difference in resin production between dehydrated and hydrated plants. We designated two study sites to test this, one hydrated and one dehydrated, and used a Scholander-Hammel Pressure Chamber to measure both water potential of stem tissue and to collect xylem resin in vials weighted on an analytical balance to estimate resin production. Results showed greater resin production in hydrated stems at predawn than in dehydrated stems. The same trend held at midday but was not significantly different between hydrated and dehydrated plants. Through this research, we were able to determine one of the ways water stress affects R. ovata, and that the reduction in the amount of resin duct flow is a direct result of the drought the plants have been experiencing over the past few years in the Santa Monica Mountains. As California’s climate changes to become drier and hotter, it is likely that native species will produce less resin during summer drought and thus be less protected from the infection and spread of fungal disease.