Cute Ornamental Plants

Species : Pachira aquatica

Synonyms : Carolinea macrocarpa, Bombax macrocarpum, B. glabrum, P. macrocarpa, etc

Common names : Malabar chestnut, Guina chestnut, provision tree, saba nut, 發財樹, 美國花生, 瓜栗, etc

Family : Malvaceae

Species : Tillandsia usneoides

Synonyms : Dendropogon usneoides, Renealmia usenoides, T. crinite, T. Filiformis, T. trichoides, etc

Common names : Spanish moss

Family : Bromeliaceae

Species : Tillandsia bergeri

Family : Bromeliaceae

Species : Dischidia ruscifolia

Common names : million hearts, etc

Family : Apocynaceae

Parthenium hysterophorus

Parthenium hysterophorus is a species of flowering plant in the aster family, Asteraceae.   Originated from the American tropics, it is now spread all over the world.  It invades all disturbed land, including farms & plantation, pastures, roadsides, park and gardens in India, Australia, Africa and Asia.

Biology

P. hysterophorus is an annual plant of the Asteraceae family. It normally grows to 30-90 cm in height, but can grow up to 1.5-2.5 m.   It occurs in humid and subhumid tropics, capable to grow on a wide variety of soil types

Flower heads are both terminal and axillary, penduculate and slightly hairy; composed of many florets formed into small white capitula, 3-5 mm in diameter.  Each head consists of 5 -8 fertile ray florets and about 40 male florets.  First capitulum forms in the terminal leaf axil, with subsequent capitula occurring progressively down to stem on lateral branches arising from the axils of the lower leaves.  Thousands of inflorescences may be produced at the apex of the plant during the season.

  

Seeds are black, flattened, about 2 mm long.  A plant can produce about 15,000-25,000 seeds.  Seeds buried in soil can remain viable for at least 4-6 years.  Germination occurred at 10-25°C, over wide range of soil pH.  Germination rate is extremely high.

 

Flowering may begin as early as 4 weeks after germination.  Life circle is about 86 days under optimum conditions, up to 335 days under unfavourable conditions.

Physiological studies have shown that P. hysterophorus has a low photorespiratory activity and has the C3 photosynthetic pathway but with positive C4 tendencies.

Its wide adaptability, photo- and thermo-insensitivity, drought tolerance, strong competition, allelopathy, high seed production, longevity of seeds in soil, small and light seeds that are capable of long distance travel via wind, water, birds, vehicles, machinery, contribute to its rapid introduction worldwide.

Noxious Weed

Parthenium hysterophorus is a vigorous weed that colonises pastures and farms.  Its presence reduce the pasture and crop production, as well as threatening the local biodiversity.

The presence of P. hysterophorus pollen grains inhibits fruit set in tomato, brinjal, bean, etc.

It found its way to India in the 1950s via contaminated wheat imported from the USA.  Today, approximately 2million hectares of land in India have been infested with P. hysterophorus.

P. hysterophorus was introduced to Australia via the movement of military aircraft and machinery during WW2 and pasture seeds.   In Queensland, it is declared a Class 2 plant under the Land Protection (Pest and Stock Route Management) Act 2002.

Health Hazard

P. hysterophorus is linked with several health problems, both in human and domesticated animals.

Contact with P. hysterophorus causes dermatitis and allergic respiratory problems in humans and cattle, due to the presence of toxin parthenin. 

Livestock fed on grass mixed with its leaves too will develop deteriorated quality of milk and meat.

It also causes diarrhoea, severe popular erythematous eruptions, breathlessness and choking.

Benefit

P. hysterophorus is used in its native neotropics as herbal remedy for various intestinal and skin disorders.  It has potential medicinal properties for skin inflammation, rheumatic pain, diarrhoea, urinary tract infections, dysentery, malaria and neuralgia.

Compost produce from P. hysterophorus can lower weed population, possibly due to allelophatic compounds present in it.  The allelophatic substances may be used as insecticide, herbicide, fungicide and nematicide.

Removal of heavy metal and dye from the environment.

Control

Chemical control with glyphosate has found to be unsuccessful.  Paraquat is effective only when the plant is young.  Manual removal can only be done when the population is small.

 

Biological control by leaf-feeding beetle from Mexico, Zygograma bicolorata is reported to be able to defoliate and kill the plant.

SecretGarden @ Melaka

Azadirachta excelsa @  Christ Church

Peltophorum pterocarpum @ Dutch Square

 Plumeria rubra @ Makam Hang Kasturi

 

Phyllanthus emblica @ Muzium Sejarah & Ethnografi

ORY-X for Effective Control of Rhinoceros Beetle

E

The Star : Dangerous weed Mushrooming

Tuesday 9th December 2014

BY TASHNY SUKUMARAN

Deadly bloom: The dangerous weed with flowers growing wildly in Sidam, Kulim.

SUNGAI PETANI: It has been dubbed the “worst weed of the century”, destroying native flora and crops, causing rashes that can leave humans permanently scarred and damaging the intestines of animals that eat it.

Called Parthenium hysterophorus, it was first detected here in September last year in Ulu Yam, Selangor.

But the highly-allergenic plant has since been spotted in Perak, Kedah and Negri Sembilan, raising fears that it has spread throughout the country.

Initial accounts show that the plant has even resisted attempts to control it through weedkillers.

A species of flowering plant native to Mexico, it can cause severe skin disease and hayfever in humans.

It is also toxic to livestock such as goats and cows, causing fevers, ulcers, anorexia and intestinal damage, and can quickly replace native flora by releasing toxic substances, causing massive crop loss.

Similar in appearance to ulam raja, P. hysterophorus is classified as a dangerous pest under the Plant Quarantine Regulations 1981 and can quickly propagate.

According to Professor Dr S. M. Rezaul Karim of Universiti Malaysia Kelantan, this is because one plant, which can reach several feet in height, can produce hundreds of thousands of seeds during its four-week life cycle.

“The seeds can be dormant in the ground for up to 10 years, making it impossible to get rid of.”

In Sg Petani, some areas had been sprayed with herbicide, only to see fresh plants springing anew just days later.

“The weed spreads like wildfire. You can look at examples in other countries, such as Australia which spends millions of dollars yearly trying to control it,” said Dr Karim, who heads the university’s parthenium weed research group.

According to Dr Karim, P. hysterophorus not only competes with other plants for nutrients – it also releases chemicals which damage other plants.

Its effect on people, he said, was particularly worrying as it often grows by the roadside where the public can easily come into contact with it.

“We need to find out how many communities in Malaysia have been affected,” he said.

“In some nations, the rash can become so bad it leaves people permanently scarred. It can take three months for the symptoms to subside,” he said.

Checks by The Star during a recent field trip to Sungai Petani saw the weed growing as high as 1.2m (4 ft) in close proximity to restaurants, paddy fields, businesses and irrigation drains that allow the seeds to hitch a ride to other areas, thus propagating its spread.

According to DOA representatives, the area had been sprayed several times with weedkiller to no avail.

In a media release, the DOA listed several methods of controlling the weed, including destroying the weed in its early stages before it flowers and produces seeds, and curbing it in residential areas using salt water in a 1:4 ratio of salt to water.

The department believes that the weed arrived in Malaysia by way of seeds being carried through imported machinery or in fertiliser.

Among the known affected areas are Kinta, Hulu Perak, Selama, Perak Tengah, Manjung, Kuala Kangsar, Pokok Sena, Hulu Selangor, Kuala Muda, Kota Setar, Seremban and Kuala Pilah.

The DOA’s Plant Biosecurity Division has formed a technical committee on the control, containment and removal of P. hysterophorus that will come up with a standard containment operating procedure and work with state governments to identify and monitor problem areas as well as destroying existing weeds.

State agricultural officers have been briefed on how to deal with the problem while an exercise to identify places where the weed grows is already underway.

Desmodium triflorum

Desmodium triflorum

Synonym : Hedysarum triflorum, Meibomia triflora

Origin & Distribution 

Desmodium triflorum is native to ther Old World tropics and subtropics.   It is currently pantropical.

Environmental Significance

Capable to grow on wide range of soil, tolerant to draught and fire, highly resistant to grazing and mowing, thus very difficult to get rid of.

Considered invasive and notorious weed, especially for lawn.