Researchers at Clemson University are bet into newfangled ways to see Asteraceae petal blight , a fungal disease that do pinch and bar to appear on the petals of certain flowers , making them unsellable . Their project seeks to minimize petal blight by finding the most common causal organisms , name them , and discovering the most in effect strategies to battle them . One class into their project , they give an update on their work , and their plans for the next year .
By Dr. Julia L. Kerrigan , Clemson University
Our undertaking was create in reply to growers in the track blossom manufacture , in particular those in the Bogota , Colombia area , who look economical losses due to the occurrence of petal blight . oftentimes , specks and streaks appear on ray florets of Asteraceae flowers ( gerbera , sunflower , chrysanthemum ) , render them unsalable . Growers have cover that Itersonilia sp . has been the most common causal agent , but this diagnosis is based on symptoms , which can be easy flurry with other causal organisms . The goal of this inquiry is to derogate petal blight by identify the common causal organism , help their designation , and generating effective fungicide program scheme .
Specific target , based on questions raised by industriousness grower , that we are currently address as part of the labor are to :
• Determine if theItersoniliathat impress momma , gerbera daisy , and sunflower is all the same coinage or if a unique species or strain infect each host species .
• Differentiate symptom from specie ofBotrytis , Stemphyllium , andAlternariafor identification by staff in the glasshouse .
The development of right geomorphologic and molecular recognition of the microorganisms will be utile to avoid misdiagnosis and ok - melodic phrase disease management practices . These orotund grower have splendid research teams and facilities , with the capableness to identify organisms with both microscopy and fundamental DNA sequencing methods . exact pathogen identification , knowledge of the disease cps , and appropriate fungicide testing and app will better control methods .
This past year , we obtained a amount of approximately 150 pounds of weakened flowers from three growers in the Bogotá , Colombia area . Samples included a variety of cultivars of gerbera , sunflower , and chrysanthemum , in addition to hydrangea . These were post in reaction to growers scouting and noticing symptom and our handiness to process them . From these samples , photographs of the symptom were ingest and cultivar were observe . Fungi were isolated using a brief rinse in 70 % ethyl alcohol and piss to remove possible saprotrophic organisms , and samples were plat on malt extract nutrient agar and corn meal agar-agar curb antibiotic . just about 80 stark cultures are being uphold .
For molecular recognition , 30 representative cultures were select . deoxyribonucleic acid was extracted from these , and amplification of the inner canned spacer region ( ITS1 , ITS4 ) was performed for DNA fingerprinting . We are sequence extra regions , starting with the declamatory subunit ribosomal RNA gene , to fortify or clarify identification . For the saki of report correct selective information , the identifications of these isolates are not being reported until they are confirmed with almost 100 % consensus through one or multiple succession .
We have an effective system of rules for march flower sample to immortalise symptoms and sequester associated fungi and we are ready to march our next time of year of samples . The information we are generating will be of use to growers throughout the country and potentially wherever environmental conditions are favorable for the pathogen . Our finish is to characterize symptoms with specific pathogen . We will continue to characterize symptom and identify kingdom Fungi involve until we can unite the two together . We calculate forward to share the issue of our work with the diligence .
