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Category: Botany

Understanding the Venus flytrap through mathematical modelling

Venus flytrap is a carnivorous plant that catches its prey mostly insects and arachnids through snap-trap movement. It has a trapping structure that is triggered by tiny hairs in the inner surface of the plant leaves.  When insect crawling along, the plant trigger to close only if it caught a live insects worthy of consumption. This unique trapping mechanism drawn attention to scientific interest and called it “one of the most wonderful in the world”. However, only recently that snap-trap closure mechanism of the Venus flytrap fully understood. On the other hand it is also been studied the trade-off investment in snap-trap structures and its energetic benefits. But a little information has been established about prey selection and why the traps allow prey to escape. This paper provides the first mathematical cost-benefit model for carnivory in the Venus flytrap and understanding its ecology.


3 Stages of Venus flytrap prey captures and digestion

Venus flytrap captures and digests its prey into three stages.  Firstly, trap is open and the lobe stand at approximately right angle to each other waiting for prey to enter. In this stage when prey moves across the trap it generates stimuli a receptor potential then action potential. Secondly, after the signal for closure the trap shut and enters in a semi-closed state. It will remain semi closed until further mechanical stimuli to make sure that live prey has been caught. Thirdly, while the prey is struggling inside the trap it will further stimulate and cause the lobes to close tighter. In fully closed state the trap has essentially transformed into a stomach and start digesting.


The investigation reveals that Venus flytrap non- prey sources such as raindrops or wind caused trap closure. This mechanism is triggered once every two days and the trap wait for more than a month for a meal. However, bigger insect around 29mm will trap fully but smaller size less than 14.2mm can escape eventually. This carnivore plant is prey selective wherein the average size of prey is 20mm. Meaning, it utilizes 68.9% of its maximum potential. Moreover, optimal trap allows 76.8% of captured prey to escape indicating that Venus flytrap is highly selective in prey capture.


Indeed, the ecology of Venus flytrap is not understood well that is why investigating capturing and digestion of prey is important. This research provides the building blocks on modelling its ecological mechanism which could incorporate various stages of trap. Since the plant is highly adaptive to its habitat the traps grow quickly.


Source: Prepared by Joan Tura from Journal of Theoretical Biology

Volume 444, 7 May 2018, Pages 1-10

Light Induces Petal Color Change in Quisqualis indica

Quisqualis indica is a spectacular vine that has yellow-green lance shaped leaves distributed mostly in tropical Asia. It is a perennial plant that normally grows in, low woods, riverside, rain forest and roadside. Yet, it can also be cultivated as ornamental plants because of its stunning flowers and mesmerizing fragrance at blooming. The flower of Quisqualis indica varies in three colors based on the flower age.  In which it started to blooms from white color petals then gradually darkens into pink then red as it reaches maturity. Moreover, the change of color in the flower is due to its potential role in attracting pollinators under cultivation conditions. However, the factors affecting these changes remain unknown. Therefore, the aim of this particular research is to determine some relevant factors affecting floral change color of Quisqualis indica.


Floral color change of Quisqualis indica

There were different parameters used in the study including pH, temperature, ethylene and light. It reveals that Quisqualis indica petal color changes reveals significantly in light rather than pH, temperature and ethylene. Wherein, it does not undergo color changes under dark condition regardless of temperature conditions. Light induced anthocyanin a gene that is responsible for color change in response to light. Thus, it implies that anthocyanin biosynthesis is regulated at the level of transcription in the presence of light.


Moreover, the pH value of Quisqualis indica over floral ontogeny did not influence the petal color change. Also flowers sprayed with ethylene did not reveals significant change suggesting that floral color change is not mediated with ethylene. On the other hand, the temperature of Quisqualis indica under 20–30 °C for four different light treatments did not change. In which at 15 °C or 35 °C the flowers did not open when exposed to constant temperature. Besides throughout the experimental period regardless of temperatures, floral color remains white.


Indeed, light is the primary factor that affects floral color change of Quisqualis indica rather than pH, ethylene and temperature. However buds and petals are sensitive to light yet flowers response highly to light than buds. But the final petal color is not expressed if only buds exposed to light which means that light during flowering period induce the final transcription.


Source: Prepared by Joan Tura from Plant Diversity 

Volume 40, Issue 1, February 2018, Pages 28-34

Anti-ulcerative colitis activity of Calotropis procera Linn

Calotropis procera Linn (Swallow wort) is a wild plant, highly branched perennial shrub that belongs to the family of Asclepiadaceae. It is believed  as medicinal plants that can be found in tropics growing on sandy and alkaline soils. Calotropis procera contains chemicals that have been used for antifungal, anticancer and insecticidal activity. It also exhibits antipyretic, anti-inflammatory, gastroprotective and antioxidant. The researcher on this study believed that Calotropis procera used as medicine in ulcerative colitis a bowel disease. The symptoms of disease is an inflammation of inner lining of the colon that caused bloody diarrhea, pus and abdominal cramping.


Effect on ulcerative colitis

Extracts of Calotropis procera were assess using rats to test its potentials as anti-ulcerative colitis. Results reveal that inflammatory indices improve better for five days after the introduction of the disease. Oral administration of Calotropis procera confers a relevant development of the disease signifying a possible treatment for ulcerative colitis. The extract of Calotropis procera contains low level of toxicity which means that other vital organs is not affected. Therefore, it is consider safe to intake orally as medicinal supplement for ulcerative colitis.


Related studies about Calotropis procera also have a positive results as anti-inflammatory because it contains useful chemicals and phytochemicals. On the other hand ulcerative colitis develops overtime and can be unbearable that sometimes leads to life threatening complications. Though, treatment is needed to lessen the signs and symptoms of the disease.


Overall, Calotropis procera has a potential to lessen the inflammation of ulcerative colitis and other diseases. Mostly the disease begins during adolescence and the severity of the inflammation changes over time. Relapses and remission also happens that last for months or years. Indeed ,Calotropis procera subsides the symptoms of ulcerative colitis and minimized the side effects to other vital systems.


Source: Prepared by Joan Tura from Saudi Pharmaceutical Journal

Volume 26, Issue 1, January 2018, Pages 75-78



Why Are There So Many Kinds of Plants?

Welcome to guest blogger, USF Botany Professor Fred Essig

Estimates vary, but there are about 300,000 named species of plants, with more being discovered daily.  There may ultimately be as many as 500,000, if and when all are catalogued. Some botanists include some 10,000 species of red and green algae in such estimates, but others include only the land plants. Either way, it’s a lot. (more…)