Pacific Island Ecosystems at Risk (PIER)


Portulaca grandiflora


RISK ASSESSMENT RESULTS: High risk, score: 9


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments

Portulaca grandiflora Hook. Family - Portulacaceae Common Names(s) - eleven-o'clock, Mexican-rose, moss-rose, onze-horas, Portulakröschen, pourpier à grandes fleurs, rose-moss, sunplant. Synonym(s) -

Answer

Score

1.01

Is the species highly domesticated?

y=-3, n=0

n

0

1.02

Has the species become naturalized where grown?

y=1, n=-1

1.03

Does the species have weedy races?

y=-1, n=-1

2.01

Species suited to tropical or subtropical climate(s) (0-low; 1-intermediate; 2-high) – If island is primarily wet habitat, then substitute “wet tropical” for “tropical or subtropical”

See Append 2

2

2.02

Quality of climate match data (0-low; 1-intermediate; 2-high) see appendix 2

2

2.03

Broad climate suitability (environmental versatility)

y=1, n=0

y

1

2.04

Native or naturalized in regions with tropical or subtropical climates

y=1, n=0

y

1

2.05

Does the species have a history of repeated introductions outside its natural range?

y=-2, ?=-1, n=0

y

3.01

Naturalized beyond native range y = 1*multiplier (see Append 2), n= question 2.05

y

2

3.02

Garden/amenity/disturbance weed y = 1*multiplier (see Append 2)

n=0

3.03

Agricultural/forestry/horticultural weed y = 2*multiplier (see Append 2)

n=0

n

0

3.04

Environmental weed y = 2*multiplier (see Append 2)

n=0

n

0

3.05

Congeneric weed y = 1*multiplier (see Append 2)

n=0

y

2

4.01

Produces spines, thorns or burrs

y=1, n=0

n

0

4.02

Allelopathic

y=1, n=0

4.03

Parasitic

y=1, n=0

n

0

4.04

Unpalatable to grazing animals

y=1, n=-1

4.05

Toxic to animals

y=1, n=0

n

0

4.06

Host for recognized pests and pathogens

y=1, n=0

n

0

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

n

0

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

n

0

4.09

Is a shade tolerant plant at some stage of its life cycle

y=1, n=0

n

0

4.10

Tolerates a wide range of soil conditions (or limestone conditions if not a volcanic island)

y=1, n=0

y

1

4.11

Climbing or smothering growth habit

y=1, n=0

n

0

4.12

Forms dense thickets

y=1, n=0

n

0

5.01

Aquatic

y=5, n=0

n

0

5.02

Grass

y=1, n=0

n

0

5.03

Nitrogen fixing woody plant

y=1, n=0

n

0

5.04

Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers)

y=1, n=0

n

0

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

0

6.02

Produces viable seed.

y=1, n=-1

y

1

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

y

1

6.05

Requires specialist pollinators

y=-1, n=0

n

0

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

y

1

6.07

Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1

See left

1

1

7.01

Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas)

y=1, n=-1

y

1

7.02

Propagules dispersed intentionally by people

y=1, n=-1

y

1

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

n

-1

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

-1

7.05

Propagules water dispersed

y=1, n=-1

n

-1

7.06

Propagules bird dispersed

y=1, n=-1

n

-1

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

n

-1

7.08

Propagules survive passage through the gut

y=1, n=-1

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

y

1

8.02

Evidence that a persistent propagule bank is formed (>1 yr)

y=1, n=-1

8.03

Well controlled by herbicides

y=-1, n=1

8.04

Tolerates, or benefits from, mutilation, cultivation, or fire

y=1, n=-1

8.05

Effective natural enemies present locally (e.g. introduced biocontrol agents)

y=-1, n=1

Total score:

9

Supporting data:

Notes

Source

1.01

No evidence.

 

1.02

1.03

2.01

(1) Native to: Argentina, Paraguay, Uruguay. (2) "Portulaca L. is primarily a tropical and subtropical herbaceous genus of South America, extending into Central America, including the Caribbean Islands, and into North America."

(1) http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?29451 [Cited 2009 December 4]. (2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

2.02

(1) Native to: Argentina, Paraguay, Uruguay. (2) "Portulaca L. is primarily a tropical and subtropical herbaceous genus of South America, extending into Central America, including the Caribbean Islands, and into North America."

(1) http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?29451 [Cited 2009 December 4]. (2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

2.03

(1) USDA zones 5-11.

(1) http://www.floridata.com/ref/p/port_gra.cfm [Cited 2009 December 7].

2.04

(1) Native to: Argentina, Paraguay, Uruguay. (2) "Portulaca L. is primarily a tropical and subtropical herbaceous genus of South America, extending into Central America, including the Caribbean Islands, and into North America."

(1) http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?29451 [Cited 2009 December 4]. (2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

2.05

(1) In this survey to identify the characteristics and habitats of non-native plant species, Portulaca grandiflora was found to be a component of the non-native flora in Chonju, Korea. (2) Portulaca grandiflora has just recently naturalized in mixed deciduous forest in Ithica, New York. (3) Naturalized in Europe.

(1) Zerbe, S., Choi, I.-K., Kowarik, I., 2004. Characteristics and habitats of non-native plant species in the city of Chonju, southern Korea. Ecological Research 19, 91-98. (2) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44. (3) http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200007019 [Cited 2009 December 4].

3.01

(1) Portulaca grandiflora has just recently naturalized in mixed deciduous forest in Ithica, New York. (2) Naturalized in Europe.

(1) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44. (2) http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200007019 [Cited 2009 December 4].

3.02

(1) Portulaca grandiflora is naturalized in gardens and has escaped to roadsides and waste places. Studies of seed surfaces from specimens representing 100 years of collections with distribution over the United States show remarkable consistency in seed morphology. Tubercles may extend onto the lateral surface, where they are widely scattered. Only one specimen was found with no tubercles at all.

(1) http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200007019 [Cited 2009 December 4].

3.03

(1) No evidence.

(1) http://www.hear.org/gcw/species/portulaca_grandiflora/ [Cited 2009 December 7].

3.04

(1) No evidence.

(1) http://www.hear.org/gcw/species/portulaca_grandiflora/ [Cited 2009 December 7].

3.05

(1) "Portulaca oleracea is a weed of arable land found throughout the United States and according to Coquillant (1951), is the eighth most common plant on earth."

(1) Zimmerman, C.A., 1976. Growth Characteristics of Weediness in Portulaca Oleracea L. Ecology 57, 964-974.

4.01

(1) No spines, thorns or burrs. (2) P. grandiflora. Prostrate to suberect annual, with branches to 30 cm long, and conspicuous trichomes at the nodes. Leaves terete to hemispherical, linear to lanceolate, 5-30 mm long and 1-5 mm wide, apex acute or subacute. Involucral leaves 8-9 (14). Open flowers 25-55 mm wide; petals pink to purple or yellow to bronze, 15-25 mm long; stamens more than 40; stigmatic branches 5-8. Capsules ovoid, 4-6.5 mm in diameter. Seeds gray-black, sometimes iridescent, flattened, round or elongate, 0.75-1 mm long, the surface tuberculate and stellate. (n=5,9) Late spring-fall

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu. (2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

4.02

Unknown

4.03

(1) Not parasitic.

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu.

4.04

(1) In this study on seed dispersal by white-tailed deer, one seed of Portulaca grandiflora germinated after passing through a deer's digestive tract. (2) Resistant to deer. (3) Deer resistant.

(1) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44. (2) http://davesgarden.com/guides/pf/go/133858/ [Cited 2009 December 4]. (3) http://www.mcdonnellnursery.com/images/download/deer_resist_plants.pdf [Cited 2009 December 7].

4.05

(1) No evidence of toxicity found in PubMed. (2) No evidence of toxicity found in ToxNet.

(1) http://www.ncbi.nlm.nih.gov/sites/entrez [Cited 2009 December 7]. (2) http://toxnet.nlm.nih.gov/cgi-bin/sis/search [Cited 2009 December 7].

4.06

(1) Portulaca grandiflora is relatively pest-free and is only occasionally bothered by mealy bugs.

(1) http://hort.ifas.ufl.edu/shrubs/PORGRAA.PDF [Cited 2009 December 7].

4.07

(1) The leaves, roots and seeds are edible. (2) No evidence of toxicity found in PubMed. (3) No evidence of toxicity found in ToxNet.

(1) http://www.pfaf.org/database/plants.php?Portulaca+grandiflora [Cited 2009 December 4]. (2) http://www.ncbi.nlm.nih.gov/sites/entrez [Cited 2009 December 7]. (3) http://toxnet.nlm.nih.gov/cgi-bin/sis/search [Cited 2009 December 7].

4.08

(1) Herbaceous. (2) P. grandiflora. Prostrate to suberect annual, with branches to 30 cm long, and conspicuous trichomes at the nodes. Leaves terete to hemispherical, linear to lanceolate, 5-30 mm long and 1-5 mm wide, apex acute or subacute. Involucral leaves 8-9 (14). Open flowers 25-55 mm wide; petals pink to purple or yellow to bronze, 15-25 mm long; stamens more than 40; stigmatic branches 5-8. Capsules ovoid, 4-6.5 mm in diameter. Seeds gray-black, sometimes iridescent, flattened, round or elongate, 0.75-1 mm long, the surface tuberculate and stellate. (n=5,9) Late spring-fall

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu. (2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

4.09

(1) Can not grow in the shade. (2) Seeds need light to germinate.

(1) http://www.pfaf.org/database/plants.php?Portulaca+grandiflora [Cited 2009 December 4]. (2) http://www.green-seeds.com/pdf/seed_starters.pdf [Cited 2009 December 4].

4.10

(1) "The plant prefers light (sandy) and medium (loamy) soils, requires well-drained soil and can grow in nutritionally poor soil. The plant prefers acid, neutral and basic (alkaline) soils." (2) Grows well in poor, sandy or gravelly soils.

(1) http://www.pfaf.org/database/plants.php?Portulaca+grandiflora [Cited 2009 December 4]. (2) http://www.floridata.com/ref/p/port_gra.cfm [Cited 2009 December 7].

4.11

(1) Succulent herb; stems usually prostrate or scrambling. (2) P. grandiflora. Prostrate to suberect annual, with branches to 30 cm long, and conspicuous trichomes at the nodes. Leaves terete to hemispherical, linear to lanceolate, 5-30 mm long and 1-5 mm wide, apex acute or subacute. Involucral leaves 8-9 (14). Open flowers 25-55 mm wide; petals pink to purple or yellow to bronze, 15-25 mm long; stamens more than 40; stigmatic branches 5-8. Capsules ovoid, 4-6.5 mm in diameter. Seeds gray-black, sometimes iridescent, flattened, round or elongate, 0.75-1 mm long, the surface tuberculate and stellate. (n=5,9) Late spring-fall

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu.(2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

4.12

(1) Succulent herb; stems usually prostrate or scrambling. (2) P. grandiflora. Prostrate to suberect annual, with branches to 30 cm long, and conspicuous trichomes at the nodes. Leaves terete to hemispherical, linear to lanceolate, 5-30 mm long and 1-5 mm wide, apex acute or subacute. Involucral leaves 8-9 (14). Open flowers 25-55 mm wide; petals pink to purple or yellow to bronze, 15-25 mm long; stamens more than 40; stigmatic branches 5-8. Capsules ovoid, 4-6.5 mm in diameter. Seeds gray-black, sometimes iridescent, flattened, round or elongate, 0.75-1 mm long, the surface tuberculate and stellate. (n=5,9) Late spring-fall

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu.(2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

5.01

(1) Succulent herb; stems usually prostrate or scrambling. (2) P. grandiflora. Prostrate to suberect annual, with branches to 30 cm long, and conspicuous trichomes at the nodes. Leaves terete to hemispherical, linear to lanceolate, 5-30 mm long and 1-5 mm wide, apex acute or subacute. Involucral leaves 8-9 (14). Open flowers 25-55 mm wide; petals pink to purple or yellow to bronze, 15-25 mm long; stamens more than 40; stigmatic branches 5-8. Capsules ovoid, 4-6.5 mm in diameter. Seeds gray-black, sometimes iridescent, flattened, round or elongate, 0.75-1 mm long, the surface tuberculate and stellate. (n=5,9) Late spring-fall

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu.(2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

5.02

(1) Succulent herb; stems usually prostrate or scrambling. (2) P. grandiflora. Prostrate to suberect annual, with branches to 30 cm long, and conspicuous trichomes at the nodes. Leaves terete to hemispherical, linear to lanceolate, 5-30 mm long and 1-5 mm wide, apex acute or subacute. Involucral leaves 8-9 (14). Open flowers 25-55 mm wide; petals pink to purple or yellow to bronze, 15-25 mm long; stamens more than 40; stigmatic branches 5-8. Capsules ovoid, 4-6.5 mm in diameter. Seeds gray-black, sometimes iridescent, flattened, round or elongate, 0.75-1 mm long, the surface tuberculate and stellate. (n=5,9) Late spring-fall

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu.(2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

5.03

(1) Succulent herb; stems usually prostrate or scrambling. (2) P. grandiflora. Prostrate to suberect annual, with branches to 30 cm long, and conspicuous trichomes at the nodes. Leaves terete to hemispherical, linear to lanceolate, 5-30 mm long and 1-5 mm wide, apex acute or subacute. Involucral leaves 8-9 (14). Open flowers 25-55 mm wide; petals pink to purple or yellow to bronze, 15-25 mm long; stamens more than 40; stigmatic branches 5-8. Capsules ovoid, 4-6.5 mm in diameter. Seeds gray-black, sometimes iridescent, flattened, round or elongate, 0.75-1 mm long, the surface tuberculate and stellate. (n=5,9) Late spring-fall

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu.(2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

5.04

(1) Succulent herb; stems usually prostrate or scrambling. (2) P. grandiflora. Prostrate to suberect annual, with branches to 30 cm long, and conspicuous trichomes at the nodes. Leaves terete to hemispherical, linear to lanceolate, 5-30 mm long and 1-5 mm wide, apex acute or subacute. Involucral leaves 8-9 (14). Open flowers 25-55 mm wide; petals pink to purple or yellow to bronze, 15-25 mm long; stamens more than 40; stigmatic branches 5-8. Capsules ovoid, 4-6.5 mm in diameter. Seeds gray-black, sometimes iridescent, flattened, round or elongate, 0.75-1 mm long, the surface tuberculate and stellate. (n=5,9) Late spring-fall

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu.(2) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104.

6.01

No evidence.

 

6.02

(1) Propagated by seed. (2) Propagate by seed. They are tiny as dust.

(1) http://www.pfaf.org/database/plants.php?Portulaca+grandiflora [Cited 2009 December 4]. (2) http://www.floridata.com/ref/p/port_gra.cfm [Cited 2009 December 7].

6.03

Unknown

6.04

(1) The flowers of Portulaca grandiflora are only "open for one day and then usually only for a few hours when the weather is sunny. On over cast days the flowers do not fully open. The flowers self-pollinate when they fail to open." (2) Self-fertile.

(1) Matthews, J.F., Levins, P.A., 1985. The Genus Portulaca in the Southeastern United States. Castanea 50, 96-104. (2) http://www.pfaf.org/database/plants.php?Portulaca+grandiflora [Cited 2009 December 4].

6.05

(1) Pollinated by insects. (2) The flowers of Portulaca grandiflora are unspecialized in terms of its requirements for insect pollinators. Almost any small insect can effect pollination e.g. beetles, butterflies and ants.

(1) http://www.pfaf.org/database/plants.php?Portulaca+grandiflora [Cited 2009 December 4]. (2) Nyananyo, B.L., 1986. Notes on the Reproductive Biology of Portulaca L. (Portulacaceae) in Nigeria. Folia Geobotanica & Phytotaxonomica 21, 431-434.

6.06

(1) Portulaca grandiflora can root from the stem nodes when they make contact with the soil.

(1) Nyananyo, B.L., 1986. Notes on the Reproductive Biology of Portulaca L. (Portulacaceae) in Nigeria. Folia Geobotanica & Phytotaxonomica 21, 431-434.

6.07

(1) Dies after first frost; readily reseeds itself.

(1) http://hort.ifas.ufl.edu/shrubs/PORGRAA.PDF [Cited 2009 December 7].

7.01

(1) Fruit a dehiscent capsule. (2) Portulaca grandiflora has seeds that just fall from the capsule. (3) Portulaca grandiflora is naturalized in gardens and has escaped to roadsides and waste places.

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu. (2) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200007019 [Cited 2009 December 4].

7.02

(1) Swallowtail gardens has Portulaca grandiflora seeds. (2) John and Jacq's garden have seeds available. [seeds may be of cultivars].

(1) http://www.swallowtailgardenseeds.com/annuals/portulaca.html [Cited 2009 December 7]. (2) http://www.jaycjayc.com/portulaca-grandiflora-annual-succulent/ [Cited 2009 December 7].

7.03

No evidence of produce contamination.

7.04

(1) Fruit a dehiscent capsule. (2) Portulaca grandiflora has seeds that just fall from the capsule. [no adaptation for wind dispersal]

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu. (2) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44.

7.05

(1) Fruit a dehiscent capsule. (2) Portulaca grandiflora has seeds that just fall from the capsule. [no adaptation for water dispersal]

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu. (2) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44.

7.06

(1) Fruit a dehiscent capsule. (2) Portulaca grandiflora has seeds that just fall from the capsule. [no adaptation for bird dispersal]

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu. (2) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44.

7.07

(1) Fruit a dehiscent capsule. (2) Portulaca grandiflora has seeds that just fall from the capsule. [no adaptation for external attachment]

(1) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu. (2) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44.

7.08

(1) In this study on seed dispersal by white-tailed deer, one seed of Portulaca grandiflora germinated after passing through a deer's digestive tract.

(1) Myers, J.A., Vellend, M., Gardescu, S., Marks, P.L., 2004. Seed dispersal by white-tailed deer: implications for long-distance dispersal, invasion, and migration of plants in eastern North America. Oecologia 139, 35-44.

8.01

(1) "Normally Portulaca grandiflora capsules contain 200 or more seeds." [cultivar description] (2) Capsules of Portulaca grandiflora cv.(P. "ulupalakua") contained a mean of 27.3 seeds per capsule. (3) Seeds minute.

(1) Zimmerman, C.A. 1977. A comparison of breeding systems and seed physiologies in three species of Portulaca L. Ecology. 58 (4):860-868. (2) Kim, I., Carr, G.D. 1990. Reproductive biology and uniform cultur of Portulaca in Hawaii. Pacific Science. 44 (2):123-129. (3) Staples, G.S.H., D.R., 2005. A Tropical Garden Flora. Bishop Museum Press, Honolulu.

8.02

(1) Viability trials of the original seed lots at 6-month intervals over the 2 1/2 year study demonstrated constancy of P. oleracea seeds. During this period P. grandiflora (a cultivar) seeds showed a significant difference between the first and last trial as geminability dropped 28% (65% to 47%).

(1) Zimmerman, C.A. 1977. A comparison of breeding systems and seed physiologies in three species of Portulaca L. Ecology. 58 (4):860-868.

8.03

Unknown (1) " Based on the results of this study alachlor, napropamide and trifluralin caused no injury to portulaca while chloropropham resulted in some reduction in plant dry weights but no significant reduction in plant quality."

(1) Hensley, D.L., Gibbons, F. D. 1985. Tolerance of some garden flowers to selected preemergence herbicides. Transactions of the Kansas Academy of Science. 88 (3-4): 146-153.

8.04

Unknown (1) Portulaca grandiflora can root from the stem nodes when they make contact with the soil.

(1) Nyananyo, B.L., 1986. Notes on the Reproductive Biology of Portulaca L. (Portulacaceae) in Nigeria. Folia Geobotanica & Phytotaxonomica 21, 431-434.

8.05

Unknown


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