Commelina diffusa
(spreading dayflower)

Pictures

Top of page

Identity

Top of page

Preferred Scientific Name

• Commelina diffusa Burm. f. (1768)

Preferred Common Name

• spreading dayflower

Other Scientific Names

• Commelina agraria Kunth (1843)
• Commelina aquatica J.K.Morton (1956)
• Commelina communis Benth., non L. (1849)
• Commelina longicaulis Jacq.
• Commelina nudiflora auct. non L.

International Common Names

• English: dayflower; french weed; pond grass; water grass
• Spanish: Babosilla; Canutillo; Tripa de pollo
• French: curage; herbe de l'eau

Local Common Names

• Bangladesh: manaina
• Cuba: canutillo
• Indonesia: brangbangan
• Japan: Shimatsuyukusa
• Philippines: alibangon
• Thailand: phak-prap

EPPO code

• COMDI (Commelina diffusa)

Taxonomic Tree

Top of page

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Monocotyledonae
•                     Order: Commelinales
•                         Family: Commelinaceae
•                             Genus: Commelina
•                                 Species: Commelina diffusa

Notes on Taxonomy and Nomenclature

Top of page C. diffusa is occasionally known by the synonyms C. nudiflora or C. communis, but these names have each been used by different authors for more than one taxon and are incorrect when applied to C. diffusa.

Description

Top of page C. diffusa is a smooth and sparsely hairy annual or perennial herb with creeping stems ascending above and branching below. It easily roots at the nodes and reproduces vegetatively and by seeds. The weed is always an annual in temperate countries while being an annual or perennial in tropical and subtropical countries, depending on moisture availability.

Distinguishing features include the long, open spathe with an acute apex, the lanceolate to broadly lanceolate leaves and seeds which are finely reticulated and ridged on one side (Holm et al., 1977); it is not geocarpic. The stem can be up to 100 cm long. The leaves are lanceolate to broadly lanceolate, 4-6 cm long, and gradually acute to acuminate. It has bracts subtending the flower (spathe), which are broad, rounded or shallow heart-shaped at the base and gradually tapering above to a rather acute apex 2-3 cm long, 1.5-2 cm wide when unfolded. There are hairs on the margins of the leaves. Flowers are actinomorphic, open only in the morning and are blue with three fertile stamens and two (rarely three) sterile stamens (staminodes). There are three free petals. The fruit is a three-celled capsule with five seeds and is 4-5 mm long. Seeds are dark brown reticulate-ribbed, ridged on one side and finely reticulated and 2-3 mm long.

Distribution

Top of page C. diffusa is found throughout the tropics of America, Africa, Asia and the Pacific, also in the subtropics in the southern part of the USA, South America, Australia and south Asian islands (Holm et al., 1977).

Distribution Table

Top of page

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Habitat

Top of page C. diffusa is a pantropical (and to some extent subtropical) weed, occurring mainly in open, moist habitats, including rice paddies. It is able to withstand saturated conditions and temporary flooding. C. diffusa is common as a weed in cultivated land, field borders, wet pasture lands, roadsides, gardens and waste places.

Host Plants and Other Plants Affected

Top of page

Growth Stages

Top of page Seedling stage, Vegetative growing stage

Biology and Ecology

Top of page C. diffusa is a perennial weed in tropical and subtropical lowlands and an annual weed in temperate countries (Holm et al., 1977). When growing in rice and other lowland crops the weed may be almost subaquatic. C. diffusa can withstand flooding and readily infests cultivated lands, roadsides, pastures and wastelands. C. diffusa is primarily a problem in young crops during the first 2-5 weeks, but it can also be a problem in mature crops due to its sprawling behaviour.

Seeds of C. diffusa which have been buried in the soil and removed at different periods showed cyclic changes in dormancy in Japan (Watanabe and Horokwa, 1975) while Nakayama (1977) showed that seedlings began to emerge at temperatures below 10°C and reached peak emergence at 10-15°C. The rate of growth and sprawling leads to rapid establishment of the weed when it infests crops. Generally the species is very persistent.

Natural enemies

Top of page

Notes on Natural Enemies

Top of page Puccinia spp. and Kordyana celebensis have been found to be natural enemies of C. diffusa.

Impact

Top of page C. diffusa is reported as a principal weed of bananas in Mexico and Hawaii; of beans, oranges, lemons, grapes, apricots, coffee and cotton in Mexico; of papaya in Hawaii; of sugarcane in Puerto Rico and sorghum in Thailand. It is also a weed in maize and vegetables in Mexico; bananas, papayas, and pineapples in the Philippines; rice in Colombia; sugarcane in Mexico and Trinidad; taro and pastures in Hawaii and coffee in Costa Rica (Holm et al., 1977). C. diffusa is also a very important weed of soyabeans in several states of the USA (Smith, 1974; Lawrence and Habetz, 1976; Baker, 1977). C. benghalensis is also present in maize in Central America (Aleman and Nieto, 1971), rice in Mexico (Alvarado and Nieto, 1971) and Costa Rica (Sancho et al., 1971) and in wheat and potatoes in Guatemala (Castillo et al., 1971a, b). C. diffusa is reported as a troublesome weed in Japan in forest nurseries (Manabe and Ishii, 1972) and citrus orchards (Takahashi et al., 1977). It is an important weed of wheat, oats, barley and soyabeans in Russia (Shcherbakova, 1974). It is difficult to control in cocoa plantations in Cameroon (Paviot, 1977) though reports from Africa are few.

C. diffusa is rated as one of the most important weeds in rice in Texas and competes vigorously for nutrients and light with that crop (Daniel, 1974). It was found to be infesting 55% of the rice area in Texas (Palmer, 1972) and increasing at a rate of 10% annually.

It is an alternative host of Cuscuta filiformis and C. sandwichiana (Raabe, 1965) and of the root-knot nematode Meloidogyne incognita (Valdez, 1968). Dhingra and Silva (1978) found a correlation between C. diffusa development and four species of fungi in Brazil.

Uses List

Top of page

General

• Ornamental

Similarities to Other Species/Conditions

Top of page Confusion can occur with a number of other weedy Commelina species, but the following combination of characters may be used to separate C. diffusa from most of them: all three petals blue, leaves narrowly elliptical (length 3-4 times width), spathe elongated, open, seeds shallowly reticulated, no stolons.

The commonest other species, C. benghalensis, has the spathe sealed along two edges to form a triangular pocket; it also has broader leaves (length 2-3 times width), stolons with underground flowers, and leaf sheaths with reddish-brown-tipped hairs.

C. forskalaei also has stolons, rough seeds, spathe sealed and leaves wavy-edged (Ivens, 1967; Holm et al., 1977; Drummond, 1984).

Two other species occurring commonly in South Asia, C. sikkimensis and C. caroliniana (=C. hasskarlii) are closely similar to C. diffusa, differing mainly in the seeds: those of C. sikkimensis being deeply pitted and those of C. caroliniana quite smooth (Noltie, 1994).

C. communis, widespread in North America and some other areas, and C. latifolia, common in Ethiopia, each have the lower petal white or very pale, not blue.

Prevention and Control

Top of page Cultural Control

C. diffusa is very difficult to control manually as the stolons are cut into small pieces which easily regenerate. The weed should be removed from the field and then desiccated for more than 2 weeks. Most of the smallholder farmers in Asia and Africa use handhoeing, handpulling and use of animal-drawn cultivators.

Chemical Control

Control using herbicides is variable depending on the herbicide, accuracy of leaf coverage and environmental conditions. As reviewed by Wilson (1981), many standard herbicides have relatively low activity on species of Commelina: these include 2,4-D, propanil, butachlor, trifluralin and pendimethalin. Herbicides with good activity on C. diffusa in rice include bentazone, molinate, oxyfluorfen and bifenox. Propanil alone gives poor control but combinations with the first three and others such as 2,4-D, thiobencarb, oxadiazon and pendimethalin have given good results. In soyabeans, bentazone and metribuzin can both be effective. In plantation crops, paraquat is not always effective, but mixture with diuron is often advocated. Glyphosate is effective, but additives or mixtures may be needed for good results at moderate doses. Best results are always likely to be achieved when the weed is small. Prodiamine has been effective in ornamental fern beds (Stamp, 1993).

Biological Control

There have not been any attempts to use biological control against Commelina spp. and the possibilities have not been explored. However, Waterhouse (1994) notes that although Commelina spp. are believed to be of Old World origin, it is curious that there are no records of agromyzid leaf miners, except from the Americas, and therefore tropical and subtropical areas of the Americas may be promising sources of candidate biological control agents.

References

Top of page

Alvarado MJ, 1971. Evaluation of several herbicide mixuters at different times in paddy rice in the Culiacan Valley, Sinaloa, Mexico. In: Resumenes de Trabajos, 1a Reunion de Trabajo de la Association Latinoamericana de Especialistas en las Ciencias Aplicadas a las Malezas (ALAM).

Alwmman RF; Neito HJ, 1971. Weed control in maize in the Torluca Valley, Mexico. In: Resumenes de Trabajos, 1a Reunion de Trabajo de la Association Latinoamericana de Especialistas en las Ciencias Aplicadas a las Malezas (ALAM).

Baker JB, 1977. Rice weed control studies (a preliminary report). 68th Annual Progress Report Rice Experiment Station, Crowley, Louisiana, 1976., 82-96

Brenan JPM, 1968. Commelinaceae. In: Flora of West Tropical Africa. Volume 3, Part 1 (Ed. by Hutchinson, J. & Dalziel, J.M.), Second Edition (Ed. by F.N. Hepper), pp. 22-50. London, UK: Crown Agents.

Budd GD; Thomas PEL; Allison JCS, 1979. Vegetation regeneration, depth of germination and seed dormancy in Commelina benghalensis L. Rhodesia Journal of Agricultural Research, 17(2):151-154

Castillo JM; Garcia JG; Rodriquez CF, 1971b. Evaluation of herbicides in potato (Solanum tuberosum) in Guatemala. In: Resumes de Trabajos, 1a Reunion de Trabajo de la Asociacion de la Associacion Latinoamericana de Especialistas en las Ciencias Aplicadas a las Malezes (ALARM).

Castillo M; Garcia JG; Rodriquez F, 1971a. Herbicide evaluation in wheat in Guatemala. In: Resumenes de Trabajos, 1a Reunion de Trabajo de la Asociacion Latinoamericana de Especialistas en las Ciencias Aplicadas a las Malezas (ALARM).

Ciba Geigy, 1982. Monocot Weeds 3. Basel, Switzerland: Ciba Geigy Ltd.

Daniel JW, 1974. Basagran for dayflower control in rice. Proceedings 27th Annual Meeting Southern Weed Science Society., 125.

Dhingra OD; Silva JFda, 1978. Effect of weed control on the internally seed borne fungi in soybean seeds. Plant Disease Reporter, 62(6):513-516

Drummond RB, 1984. Arable weeds of Zimbabwe. A guide to the recognition of more important arable weeds of crops. Harare, Zimbabwe: Agricultural Research Trust.

Holm LG; Pancho JV; Herberger JP; Plucknett DL, 1979. A geographical atlas of world weeds. New York, USA: John Wiley and Sons, 391 pp.

Holm LG; Plucknett DL; Pancho JV; Herberger JP, 1977. The World's Worst Weeds. Distribution and Biology. Honolulu, Hawaii, USA: University Press of Hawaii.

Ivens GW, 1967. East African Weeds and their Control. Nairobi, Kenya: Oxford University Press.

Lawrence RM Jr; Habetz R, 1976. Soybean herbicide experiments (a preliminary report). 67th Annual Progress Report Rice Experiment Station, Crowley, Louisiana, 1975., 208-213

Lorenzi H, 1982. Weeds of Brazil, terrestrial and aquatic, parasitic, poisonous and medicinal. (Plantas daninhas de Brasil, terrestres, aquaticas, parasitas, toxicas e medicinais.) Nova Odessa, Brazil: H. Lorenzi, 425 pp.

Manabe T; Ishii K, 1972. Weed control in the forest nursery with CFNP (MO-500). Weed Research, Japan, No. 13:22-25

Nakayama K, 1977. Weed control in upland farming of Japan. JARQ [Japanese Agricultural Research Quarterly], 11(2):84-88

Noltie HJ, 1994. Flora of Bhutan. Volume 3 Part 1. Edinburgh, Scotland: Royal Botanic Gardens.

Oviedo Prieto R; Herrera Oliver P; Caluff MG, et al. , 2012. National list of invasive and potentially invasive plants in the Republic of Cuba - 2011. (Lista nacional de especies de plantas invasoras y potencialmente invasoras en la República de Cuba - 2011). Bissea: Boletín sobre Conservación de Plantas del Jardín Botánico Nacional de Cuba, 6(Special Issue 1):22-96.

Paviot J, 1977. A new herbicide trial in a cacao plantation at the Station de Nkoemvone. Cafe Cacao The, 21(1):41-46

Pritchard GH, 1971. Weed control in Arabica coffee in the central highlands of New Guinea. In: Proceedings 3rd Conference of the Asian-Paccific Weed Science Society, Kuala Lumpur No. 14.

Raabe R, 1965. Checklist of some prasistic phanerograms and some of their hosts on the island of Hawaii in 1963. Plant Disease Reporter, 49(7):583-585.

Sancho EC; Chavarria PL; Garcia JG, 1971. Herbicide trials in rice in Costa Rica. Resumenes de tabajos, 1a Reunion de Trabajo de la Associacion Latinoamericana de Especialistas en las Ciencias Aplicads a las Malezes (ALARM).

Smith RJ Jr, 1974. Herbicide combinations for weed control. Rice Journal, 77(7):31-32

Stamps RH, 1993. Prodiamine suppresses spreading dayflower (Commelina diffusa) facilitating hand-weeding in leatherleaf fern (Rumohra adiantiformis) ground beds. Journal of Environmental Horticulture, 11(2):93-95

Stroud A; Parker C, 1989. A Weed Identification Guide for Ethiopia. Rome, Italy: Food and Agriculture Organization.

Takahashi K; Sakai Y; Harada Y; Hirose K, 1977. Effect of ten years' application with bromacil in citrus (Satsuma mandarin) orchard. 1. Effects of bromacil on annual variations of weed species and population. Weed Research, Japan, 22(4):198-202

Watanabe Y; Hirokawa F, 1975. Ecological studies on the germination and emergence of annual weeds. 4. Seasonal changes in dormancy status of viable seeds in cultivated and uncultivated soil. Weed Research, Japan, 19:20-24.

Waterhouse DF, 1993. The Major Arthropod Pests and Weeds of Agriculture in Southeast Asia. ACIAR Monograph No. 21. Canberra, Australia: Australian Centre for International Agricultural Research, 141 pp.

Wilson AK, 1981. Commelinaceae - a review of the distribution, biology and control of the important weeds belonging to this family. Tropical Pest Management, 27(3):405-418

Distribution Maps

Top of page