Bibliography & Biology Outline of Galinsoga spp.

 

Prepared by: David Kagima, April 2000

 

 

 

 

 

 

 

Galinsoga spp.

 

Asteraceae - Sunflower Family

(G.parviflora, G. ciliata, G. quadriradiata)

 

Common names - Gallant soldier (E), Shaggy soldier (E), Quick weed (E), Water weed (E), Macdonaldi (E), Kang’ei (Kikuyu), Msekeseke (Kiswahili).

 

 

 

Biology Outline

 

Introduction

(Distribution and Habitat)

Galisoga is an annual herb found in most temperate and subtropical regions of the world as a weed of many crops and waste land. In Africa, its distribution is wide spread, ranging from 0-2000m above sea level (Terry & Michieka 1987). It is known to have been growing in the Bartram botanical garden in Philadelphia in 1836, and the earliest recorded naturalized populations in the US were not far from Philadelphia, in Baltimore, eastern Pennsylvania, and New York, suggesting that it may have escaped from there (Shontz and Shontz 1970). In Nebraska (US), it is scattered throughout and it is most common in the eastern one-half in shady and wet areas of fields, gardens, farm yards, waste places and lawns (Stubbendieck et al. 1995). As the map below shows, the species is now present in all parts of New England (US). The weed is native to Central and South America, but due to human activity has spread far from its original range to become “a cosmopolitan weed” (Gleasen & Cronquist 1991). Galinsoga has names related with speed and violence! Gallant soldier, Quick weed, Water weed, Msekeseke (a kiswahili word that means ‘fast’), Kang’ei (a Kikuyu word that means ‘one who hacks/chops off heads’). And in Ohio (US), like “water”, it spreads everywhere. These names clearly indicate that the weed is difficult to manage.

 

Click on map to view

MAP!

 

1)   Seed

 

1.1) Seed Production

 Galinsoga has a fruit that is an achene, angled or flat , black slightly hairy and about 1.5mm long. Propagation is by seed (Terry and Michieka 1987). Seeds are enclosed in an achene and  are small, measuring 1.5mm long (Stubbendieck et al. 1995). A plant 8-9 weeks old can produce 3000 flower heads and over 7000 viable seeds. Galinsoga can produce as much as 125 million seeds per acre (Rutgers Coop Ext. 1999). Usami (1976) working in Japan estimated that one plant of G. parviflora in its life-time produces a total of 400,000 seeds.

 

1.2) Dispersion

The plant may be spread about by several means. The small, lightweight seeds (technically fruits) can be blown short distances by the wind, and are covered with short stiff hairs which help them cling to the fur of animals or the clothing of humans. They can also be transported in soil. Early records of the species in the US were concentrated in and around cities, while for a time the plant remained relatively rare in rural areas, suggesting that long distance dispersal was accomplished mostly through the activities of humans, as an inadvertent consequence of travel and commerce (Shontz  and Shontz 1970).

Galinsoga can spread one mile in 10 years and became naturalized in England 150 years after introduction into the Kew Botanical Garden (Rutgers Coop Ext. 1999). 

 

1.3) Seed Dormancy & Beed Bank

Seeds are not dormant and can germinate immediately upon contact with warm moist soil. Temperatures of 50-90 degrees F are best for germination. Galinsoga is called gallant soldier and quick weed because seeds start to germinate on their way to the ground so that several generations are possible each growing season (Rutgers Coop Ext. 1999).

As its seeds lack dormancy (Ivany and Sweet 1973), seedling recruitment takes place whenever temperature and moisture conditions become favorable (Usami 1976). The weed maintains itself by seed which over-winters on or under the surface of the soil (Warwick and Sweet 1983). Sown on the soil surface and grown in natural light, 73% germination was reported after 1 week and 86% germination after 7 weeks (Warwick 1983). Ivany and Sweet 1973 observed that  seedling emergence for G. parviflora occurred in May and June. Ivany (1971) examined the effect of soil depth and found that emergence decreased from 98% for seed sown on soil surface to 56% at 0.25 cm, with no germination for seed buried at a depth of 1.0 cm. Studies by Kahl and Ashley (1977) indicated a very positive germination response to light in G. quadriradiata. In the light the germination range was 94-98% compared to

1-15%  germination in the dark.

 

2) Development

 

2.1) Architecture, size & phenalogic stage

Galinsoga  is a forb and an abundant seed-producing summer annual with hairy leaves and stems. At seedling stage, it produces club-shaped cotyledons with slightly indented tip. The stem below the cotyledon ( hypocotyl) is very short, green, becoming maroon with age. Young leaves are opposite, triangular with slightly toothed margins, and covered with hairs. It has a shallow fibrous root system. The stem is erect, branched, grows up to 60cm high and is slightly hairy. Leaves are opposite, up to 6cm long and 4cm wide, simple, ovate and slightly hairy. Three distinct veins mark the leaf, converging at the base and the margin is shallowly toothed. The inflorescence is flower heads 5-8mm in diameter on stalks 12-25mm long. The leafy inflorescence is regularly branched at the stem apex and from upper leaf axils. Flower heads consist of many yellow tubular florets, and 4-5 white 3-lobed ray florets sorrounded by membranous bracts. Fruit is an achene and propagation is by seed (Terry and Michieka 1987).

PICTURES!

 

  seedlings showing cotyledons  

                  

 

 

 

         

 leaves opposite oval to triangular

 

 

                            

 stems erect reaching 2ft high

 

 

                            

 fruit a brown to black achene

 

                  

 many flowers produced from terminal stems

 

 

3) Interspecific Interaction

 

3.1) Competition

Galinsoga is highly competitive and quickly spreads and becomes dominant in a field (Univ. of Conn. Ext. 2000). A study by Rai and Tripathi (1984) indicated that at higher altitude, G. ciliata was more successful as indicated by its higher population density, longer life of its first and second cohorts and greater biomass production in crop fields. Seedling recruitment and survivorship of cohorts were significantly influenced by mode of cultivation, crop type and altitude. The growth of the weed was affected by altitude and crop type as indicated by its poor performance in radish field at lower altitude than at higher altitude (Rai and Tripathi 1984).

Due to their susceptibility to competition, these weeds are rarely present in established grasslands or other dense crop stands (Babu 1969). Reduction in yield of vegetables from competition depends on crop, with little or no losses with competitive crops. Studies in Connecticut and New York by Ashley (1972), and Senesac and Minotti (1979), respectively reported losses of 50% in yield of snap beans. Stilwell and Sweet (19750 reported 10% reduction in yield of cabbage. Vine growth of tomato was reduced by 23% in plots heavily infested with Galinsoga (Warwick and Sweet 1983).  

 

3.2) Predators and Parasites

Galinsoga serve as alternate host for many insects, viruses and nematodes which affect crop species (Warwick and Sweet 1983) .The weed takes hold like a wild fire. It grows among lower growing crops and can transmit mosaic virus to them. Galinsoga Mosaic virus was first reported in Galinsoga parviflora from Queensland, Australia, where it spreads (Behncken 1970). Virions are found in all parts of the host plant in the cytoplasm. Inclusions and multivesicular bodies are present in infected cells. Chlorotic or necrotic local lesions, systemic mosaic and leaf malformation are common symptoms in Galinsoga parviflora. The virus is transmitted without a vector through soil (mechanical innoculation). It is neither transmitted by contact between plants nor by seed. It spreads to susceptible crop families such as Amaranthaceae, Chenopodaceae, Compositae, Leguminasae, solanaceae and umbelliferae (Behncken 1970).

 Galinsoga parviflora  is a resorvoir for wilt virus that attacks tomatoes and for cucumber mosaic virus, curly top virus and aster yellow yellow viruses all of which infect many crops species (Batra 1979). Studies by Batra (1979) showed that Galinsoga harbored 122 species of insects and one mite as either phytophages or pollinators and 22 species of insect pests of crops in maryland and Guatemala. The galinsogas also serve as hasts for a number of nematodes species which affect crops. These include the northern root.knot nematode, chitwood, bulb nematode, root nematodes and sugarbeet eelworm (Bendixen et al 1979)

 

4) Intraspecific Interaction

 In a given sowing pattern, seed germination of both galinsoga parviflora and G. ciliata declined with increase in sowing density. Density-induced reduction in seed output was observed at high densities. Galinsoga ciliata could tolerate greater density stress than G. parviflora. The effect of various physical factors was exaggerated at high population densities which showed that the severity of intraspecific competition coupled with environmental constraints operating at different stages of the life cycle contributes a great deal to the population regulation of these weeds (Rai and Tripathi 1983).

 

5)  Reproduction

 

5.1) Flowering, growth and development

The biology or life cycle of Galinsoga makes it a successful weed. The plant can complete its life cycle (produce seeds) in as little as 50 days. The weed begins to produce flowers as early as the sixth or seventh node. Each flower head contains an average of 24 viable seeds. Galinsoga continues to flower throughout summer until frost. It is a significant problem because of its continuous flower habit, ability to germinate late in the season avoiding late cultivation, the great number of viable seeds produced and lack of dormancy (Rutgers Coop Ext. 1999). Within a given crop cycle, several cohorts of seedling emerge at different time intervals (Rai and Tripathi 1984). Studies by Ivany and Sweet (1973) indicated that both species of galinsoga had large increases in plant height and weight with longer photoperiod (16-h). Both Galinsoga parviflora and

G. quadriradiata produce by cross- and self-fertilization (Canne 1977). Ivany (1971) and Usami (1976) have described three to four generations per growing season in populations from New York state and Japan, respectively.

 

5.2) Genetic variation

One case of suspected intergeneric hybridization involving Galinsoga quadriradiata

(n = 16) and Sabazia sarmentosa Less. Var. Sarmentosa (n = 24) has been described from Mexico by canne (1977). Putative hybrids are morphologically intermediate and apparently sterile. Gopinathan and Babu (1982) have described a triploid hybrid (3n = 24) between G. parviflora ( 2n = 16) and G. quadriradiata (2n = 32) from an area of India where the two species co-occur. The hybrid was characterized by 0% pollen viability and the presence of morphological featrues of both species.

 

 

6) Weed Management

 

6.1)Chemical

Galinsoga is best controlled when in early bloom to prevent seed production. It is an annual weed that is a perennial problem for many growers. The weed can produce great number of viable seeds, lacks seed dormancy and shoots cut during hoeing or cultivation can root rapidly even in semi-moist soils. Herbicides that provide good control are Tillam, Atrazine, Goal, Karmex, lasso, Lorox, Sencor, Lexone, Gramoxone, Lentagran, Bladex, Dual and Command (Rutgers Coop Ext. 1999). Other chemicals include alachlor, cyanazine, dynoseb, linulon, metolachlor and paraquat (Romanowski and Fulmer 1974; Ivany 1976; Mc-Laughlin and Sweet 1974; Mohammed and Sweet 1974, 1976; Hartfield et al. 1978; Hughes and Sweet 1978).

 

6.2) Non-chemical

It is advised that if you do not have Galinsoga, prevent it! In Connecticut, it is invading farms on which it has not been previously seen. Fields are scouted in early June, especially edges. If seen, vegetable growers, particularly in the Connecticut River Valley are advised to use hand hoeing or other measures to eliminate it. Crop rotation is also encouraged. The weed is a problem in cole crops, peppers and squashes. Rotation with corn and tomatoes is good in which herbicides are available to give good weed control. also these crops have enough height to them to discourage the weed. To avoid spreading it, equipment must be cleaned after working in infected fields. Eradication is another weed management program for highly infested fields. A summer cover crop of Sudan grass and sorghum can be used to suppress the weed. Galinsoga seeds are relatively short-lived in the soil, and so if plants are prevented from going to seed for several years, this nasty weed could be greatly reduced in numbers if not eliminated. Repeated discing of the field ensures that it stays weed free all season (Univ. of Conn. Ext. 2000). Black plastic mulch is a good control in intensive agriculture production or in home horticulture (Sweet 1978).

         

7) Usage and properties

The young stems and leaves of quickweed can be cooked and eaten as greens. The weed is none poisoning (Stubbendieck et al. 1995). In Java, the leaves of the two species are eaten by humans (Batra 1979).

 

8) Other topics

Soil texture and soil moisture play a role in regulating population growth in Galinsoga. A study by Rai and Tripathi 1983 showed that an increased proportion of sand in soil resulted in higher seed production. Also, a  substantial decrease in seeds and dry matter was observed at low moisture level. Sudies conducted by Ivany (1971) showed that Galinsoga spp. prefer high levels of N, P and K.

 

 

Bibliography

 

 

Introduction

 

Gleason, H. A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and adjacent Canada, 2nd edition. New York, The New York Botanical Garden.

 

Rich, W. P. 1900. Some New Acquaintances. Rhodora 2;203-205.

 

Rich, W. P. 1902. Preliminary Lists of New England Plants. IX. Polygonaceae. Rhodora4:203-206.

 

Shontz, N. N. and J. P. Shontz. 1970. Galinsoga ciliata (Compositae): its arrival and spread in the Northeastern United States. Rhodora 72:386-391.

 

Terry, P. J., and R. W. Michieka. 1987. Common Weeds of East Africa. Food and Agriculture Organization of the United Nation, 00100 Rome, Italy.

 

1) Seed

 

Seed production

Cavers P. B. 1983. Seed demography. Canadian Journal of Botany 61, 3578-90.

 

Fenner M. 1985. Seed ecology. London, UK: Chapman  and Hall.

 

Hawthorn W. R. and P. B. Curves. 1976. Population dynamics of the perrenial herbs, Plantago major L. and P. rugelli Denec. Journal of Ecology 64 : 511 -27.

 

Misra J., H. N. Pandey, R. S. Tripathi, and U. K. Sahoo. 1992. Weed population dynamics under jhum (slash and burn agriculture) and terrace cultivation in Norther India. Agriculture Ecosystem and Environment 41 : 285-95.

 

Rutgers Cooperative Extension. 1999. Cook College, 88 Lipman Drive, New Brunswick, NJ 08901-8525.

 

Stubbendieck J., G. Y. Friisoe., M. R. Bolick. 1995. Weeds of Nebraska and the Great Plains. Nebraska Department of Agriculture. PO Box 94756. Lincoln, Nebraska-Lincoln.

 

Usami . 1976. Ecological studies on weeds in Mulberry fields. 2. Auto-ecology of Galinsoga parviflora Cav. Weed Res. (Japan) 21 : 76-80.

 

Yadav A. S. And R. S. Tripathi. 1981. Population dynamics of the ruderal weed Eupatorium odoratum and its natural regulation. Oikos 36 : 355-61.

 

Seed survival and seed embryo

 

Black M. 1969. Light controlled germination of seeds. Dormancy and Survival. Symposium of society for Experimental Biology 23:193-218.

 

Borthwick H. A., S. H. B. Hendricks, E. H. Tools 1954. Action of light of lettuce seed germination. Botanical Gazzete 115-205.

 

Eddleman L. E. and J. T. Romo. 1988. Spotted knapweed germination response to stratification, temperature and water stress. Canadian Journal of Botany 66 : 653-57.

 

Egly G. H. 1990. High temperature effects on germination and survival of weed seeds in soil. Weed Science 38 :429-35

 

Ferndex Quintanilla C.,  J. L. Gonzalez Andujar, and A. P. Appleby. 1990. Characterization of the germination and emergence response to temperature and soil moisture of Avena fatua and A. sterelis. Weed Research 30 : 289-95.

 

Howell. N. 1981. The effect of seed size and relative emergence time on fitness in a natural population of Impatiens capensis Mecrb. (Balsaminaceae). Am. Midl. Nat. 105 : 312-320.

 

Inouye R. S. 1980. Density-dependent germination response by seeds of desert annuals. Oecologia (Berl.) 46 : 235-238.

 

Ivany J. A. and R. D. Sweet 1973. Germination, growth, development and control of Galinsoga. Weed Sci. 21 : 41-45.

 

Roberts H. A., and M. E. Rickets. 1979. Quantitative relationships between the weed flora after cultivation and the seed population in the soil. Weed Research 19, 269-75.

 

Roberts H. A., and P. M. Feast. 1970. Seasonal distribution of emergence in some annual weeds. Experimental Horticulture 21, 36-41.

 

Ross M. A. and Harper J. L. 1972. Occupation of biological space during seedling establishment. J. Ecol. 60 : 77-88.

 

Waite S. And Hutchings M. J. 1978. The effects of sowing density, salinity and substrate upon the germination of seeds of Plantago coronopus L. New Phytol. 81 : 341-348.

 

Dispersion

 

Cousens R., and M. Mortimer. 1995. Dynamics of Weed Populations. Cambridge University Press, Cambridge.

 

Crawley M. J., P. H. Harvey and A. Purvis. 1996. Comparative ecology of the native and alien floras of the British Isles. Phil. Trans. R. Soc. B 351, 1251-1259.

 

Forcella F., J. T. Wood and S. P. Dillon. 1986. Characteristics distinguishing invasive weeds within Echium (Buglos). Weed Res. 26, 351-364.

 

Fryer G. 1991. Biological invasions in the tropics: Hypothesis versus reality. In: Ecology of Biological Invasion in the Tropics. International Scientific Publications, New Delhi.

 

Kokwaro J. O. 1994. Flowering Plant Families of East Africa. An introduction to plant taxonomy. East African Educational Publishers, Nairobi.

 

Macdonald I. A. W., F. J. Kruger and A. A. Ferrar. 1986. The Ecology and Management of Biological Invasions in Southern Africa. Oxford University Press, Oxford.

 

Misra J., H. N. Pandey, R. S. Tripathi and U. K. Sahoo. 1992. Weed population dynamics under ‘jhum’ (slash and burn agriculture) and terrace cultivation in north-east India. Agriculture Ecosystems and Environment 41, 285-95.

 

Pysek P. 1995. Recent trends in studies on plant invasions. In: Plant Invasions - General Aspects and Special Problems. SPB Academic Publishing, Amsterdam.

 

Rapoport E. H. 1991. Tropical versus temperate weeds: a glance into the present and future. In: Ecology of Biological Invasion in the Tropics. International

Scientific Publications, New Delhi.

 

Rutgers Cooperative Extension. 1999. Cook College, 88 Lipman Drive, New Brunswick, NJ 08901-8525.

 

Saxena K. G. 1991. Biological invasions in the Indian sub-continent: review of invasions by plants. Ecology of Biological Invasions in the Tropics. International Scientific Publications, New Delhi. 

 

Shontz N. N. and J. P. Shontz. 1970. Galinsoga ciliata (Compositae): its arrival and spread in the Northeastern United States. Rhodora 72:386-391.

Singh P. 1976. Lantana weed and Lantana Lace bug. Indian For. 102, 474-476.

 

Sokal R. R., and F. J. Rohlf. 1981. Biometry. Freeman, New York.

 

Stadler J., G. Mungai, and R. Brandl. 1998. Weed invasion in East Africa: insights from herbarium records. African Journal of Ecology, Vol. 36, pp 15-22.

 

Usami Y. 1976. Ecological studies on weeds on mulberry fields. 2. Autoecology of Galinsoga parviflora. Cav. Weed Res. Japan 21(2); 76-80.

 

Seed Dormancy & Seed Bank

 

14-16 Sept, 1988, Dijon, France, pp. 71-80.

 

Ball D. A. and S. D. Miller 1989. A comparison of techniques for estimation of arable soil seed banks and their relation ship to weed flora. Weed Research 29, 365-73.

 

Ballard L. A. T. 1958. Studies of Dormancy in the seeds of subterranean clover (Trifolium subterranean L.) Breaking of dormancy by CO2 and by activated carbon. Aust J. Biol. Sci. 2 : 246-260.

 

Baskin J. M. and C. C. Baskin. 1990. The role of light and alternating temperatures on germination of polygonum aviculare seeds exhumed on various dates. Weed Research 30 : 397-401.

 

Benjamin L. R. 1990. Variation in time of seedling emergence within populations: A feature that determines individual growth and development. Advances in Agronomy 44 : 1-25.

 

Harper J. L. 1957. The ecological significance of dormancy and its importance in weed control. Proceedings of 4th International Conference on Plant Protection, Hamburg,

 

Hayashi I., J. V. Pancho and S. S. Sastroutomo. 1978. Preliminary report on the buried seeds of floating Islands and bottom of Lake Rawa Pening, Central Java. Japanese Journal of Ecology 28, 325-33.

 

Ivany J. A. 1971. Galinsoga ciliata and Galinsoga parviflora : Germination, growth, development and control. Ph.D. Thesis, Cornell University. 164 pp.

 

Ivany J. A. and R. D. Sweet 1973. Germination, growth, development and control of Galinsoga. Weed Sci. 21 : 41-45.

 

Ivany J. A. and R. D. Sweet. 1973. Germination, growth, development and control of Galinsoga. Weed Science 21:41-5.

 

Khal D. J. and R. A. Ashley 1977. The effect of light on Galinsoga ciliata achene germination. Proc. Northeast. Weed Sci. Soc. 31 :141-143.

 

 Khal D. J. and R. A. Ashley 1979. Responses of tomato and galinsoga to water stress. Proc. Northeast. Weed Sci. Soc. 33 : 119.

 

Kropac Z. 1966. Estimation of weed seeds in arable soil. Pedobiologia 6, 105-28.

 

Malone C. R. 1967. A rapid method for enumeration of viable seeds in soil. Weeds 15, 381-2.

 

Moss S. R. 1988. Influence of cultivations on the vertical distribution of weed seeds in soil. 8th International Symposium on the Biology, Ecology and Systematics of Weeds,

 

Rai J. P. N. and Tripathi R. S. 1982. Adaptive significance of seed reserves in ray achenes  of Galinsoga parviflora Cav. Experentia38  804-5.

 

Roberts H. A. 1962. Studies on the weeds of vegetable crops. Effect of six years of cropping on the weed seeds in the soil. Journal of Ecology 50, 803-13.

 

Roberts H. A. 1970. Viable weed seeds in cultivated soils. Report of National Vegetable Research Station for 1969, pp. 25-38.

 

Roberts H. A. 1981. Seed banks in soil. Annals of Applied Biology 6, 1-55.

 

Roberts H. A., and P. A. Dawkins. 1967. Effect of cultivation on the numbers of viable weed seeds in soil. Weed Research 7, 290-301.

 

Rutgers Cooperative Extension. 1999. Cook College, 88 Lipman Drive, New Brunswick, NJ 08901-8525.

 

Thompson K., and J. P. Grime. 1979. Seasonal variation in the seed banks of herbaceous species in ten contrasting habitats. Journal of Ecology 67, 893-921.

 

Usami Y. 1976. Ecological studies on weeds in Mulberry fields. 2. Autecology of Galinsoga parviflora Cav. Weed Research 21: 76-80.

Vol. 1, pp. 415-20.

 

Warwick S. I. and R. D. Sweet. 1983. The biology of Canadian weeds. 58. Galinsoga parviflora and G. quadriradiata (= G. ciliata). Can. J. Plant Sci. 63 : 695-709.

 

Yadav A. S., and R. S. Tripathi. 1982. A study on seed population dynamics of three weedy species of Eupatorium. Weed Research 22, 69-76.   

 

2) Development

 

Architecture, Size and Phenalogic Stage

 

Ivany J. A., and R. D. Sweet. 1973. Germination, growth, development and control of Galinsoga. Weed Sci. 21: 41-5.

 

Stubbendieck J., G. Y. Friisoe., M. R. Bolick. 1995. Weeds of Nebraska and the Great Plains. Nebraska Department of Agriculture. PO Box 94756. Lincoln, Nebraska-Lincoln.

 

Terry, P. J., and R. W. Michieka. 1987. Common Weeds of East Africa. Food and Agriculture Organization of the United Nation, 00100 Rome, Italy.

 

 

3) Interspecific Interaction

 

Competition

 

Akhtar N., H. H. Naqui and F. Hussain. 1978. Biochemical inhibition (allelopathy0 exhibited by Cenchrus ciliaris and Chrysopogan aucheri. Pakistan J. For., 28:194-200.

 

Ashley R. A. 1972. Effect of competition and control of Galinsoga ciliata (Raf.) Blake in snap beans. Proc. Northeast. Weed Contr. Conf. 26 : 338-341.

 

Babu C. R. 1969. Galinsoga ciliata (Raf.) Blake (Asteraceae) - a species new to India. Bull. Bot. Surv. India. 11 :184-185.

 

Ford E. D. 1975. Competition and stand structure in some even-aged plant monocultures. J. Ecol. 63 ; 311-333.

 

Harper J. L. 1961. Approaches to the study of plant competition. Symp. Soc. Exp. Biol. 15 : 1-39.

 

Palmblad I. G. 1968. Competition in experimental populations of weeds with emphasis on the regulation of population size. Ecology, 49 : 26-34.

 

Rai J. P. N. and Tripathi R. S. 1984. Population dynamics of  different seedling cohorts of two co-existing annual weeds, Galinsoga ciliata and G. parviflora, on two contrasting sites. Acta, Oecologia Plantaram 5 : 357-68.

 

Senesac A. F. and P. L. Minotti. 1979. Competition between red kidney beans and annual broadleaf weeds. Proc. Northeast, Weed Sci Soc. 33 : 108 (Abstr.)

 

Shwar C. 1976. Changes in weed flora in intensive potato cropping. Nachrichtenbl. Pflanzenschutz. D. D. R. 30: 25-9.

 

Stilwell E. K. and R. D. Sweet 1975. Galinsoga ciliata and Galinsoga parviflora control in cabbage and brocolli. Proc. Northeast. Weed Control Conf. 29 : 239-243.

 

University of Connecticut - IPM Extension. 2000. Http://www.cla.lib.ct.us/canr/ces/ipm/weeds/htms/galnsoga.htm

 

Vengris, J. 1953. Weed populations as related to certain cultivated crops in Connecticut River Valley, Mass. Weeds 2: 125-34.

 

Predators and Parasites

 

Aristeguieta L. 1964. Flora de venezuela X, pp. 659.

 

Babu C. R. 1969. Galinsoga Ciliata Blake (Asteraceae) - a species new to India. Bull. Bot. Surv. India 11, 1&2: 184-5.

 

Batra S. W. T. 1979. Insects associated with weeds of the Northeastern United States: Quickweeds,  and G. parviflora (compositae). Environ. Entomol. 8 : 1078-1082.

 

Behncken, G. M. 1970. Aust. J. Biol. Sci. 23;497.

 

Behncken, G. M., Francki, RIB. and A. J. Gibbs. 1982. CMI/AAB Descr. Pl. Viruses No. 252, pp 4.

 

Bendixen L. E. Reynolds, D. A. and R. M. Riedel. 1979. An annotated bibliography of weeds as reservoirs for organisms affecting crops. I. Nematodes. Ohio Agricultural Research and Development Center Res. Bulletin 1109. 64 pp.

 

Bruckart W. L., and J. W. Lorbeer. 1976. Cucumber mosaic virus in weed hosts near commercial fields of lettuce and celery. Phytopathology 66: 253-9.

 

Carter W. 1962. Insects in Relation to Plant Diseases. J. Wiley Publ. N. Y., pp 705.

 

Hatta, T. and Francki, RIB. 1981. J. Ultrastruct. Res. 74:116.

 

Herbert D. A. 1939. Plant viruses in Queensland. Univ. Queensland Papers Dept. Biol. 1; 1-4.

 

Miller P. R., F. Weiss and M. J. Obrien. 1960. Index of plant diseases in the United States. USDA Agric. Handb. No.165: pp 531.

 

Mulligan G. A. and P. G. Kevan. 1973. Color, brightness and other floral characteristics attracting insects to the blossoms of some Canadian weeds. Can. J. Bot. 51; 1939-52.

 

Plekhanova T. I., V. A. Bandyukova and G. A. Mikhailova. 1977. Flavonoids of Galinsoga parviflora  Khim. Prirod. Soedinenii. 6: 862.

 

Rai J. P. N. and Tripathi R. S. 1985. Effect of herbivory by the slug, Mariaella dussumieri and certain insects on growth and competitive success for two sympatric annual weeds. Agriculture ecosystems and Environment 13 : 125-37.

 

Shukla, D. D., G. J. Shanks, D. S. Teakle, and G. M. Behncken 1979. Aust.J. Biol. Sci. 32:267.

 

Skotnicki, A. and A. J. Gibbs. 1981. Australas. Pl. Path. 10:27.

 

Warwick S. I. and R. D. Sweet. 1983. The biology of Canadian weeds. 58. Galinsoga parviflora and G. quadriradiata (= G. ciliata). Can. J. Plant Sci. 63 : 695-709.

 

4) Intraspecific Interaction

Rai J. P. N. and R. S. Tripathi. 1983. Population regulation of Galinsoga ciliata and g. parviflora. Weed Research. 23 : 151-163.

 

Williams R. d. and B. F. Ingber. 1977. The effect of intraspecific competition on the growth and development of Johnson grass under greenhouse conditions. Weed Sci. 25 : 293-297.

 

5) Reproduction

 

Flowering, growth and development

 

Ballare C. L.,  A. L. Scopel, C. L. Chersa and Sanchez R. A. 1987. The demaography of Datura ferox (L.) in soybean crops. Weed Research 27 : 91-102.

 

Bazzaz F. A. and R. W. Carlson. 1979. Photosynthetic contribution of flowers and seeds to reproductive effort of an annual colonizer. New Phytol. 82 : 223-232.

 

Canne J. M. 1977. A revision of the genus Galinsoga (Compositae : Heliantheceae). Rhodora 79 : 319-389.

 

Ivany J. A. 1971. Galinsoga ciliata and Galinsoga parviflora : Germination, growth, development and control. Ph.D. Thesis, Cornell University. 164 pp.

 

Ivany J. A. and R. D. Sweet 1973. Germination, growth, development and control of Galinsoga. Weed Sci. 21 : 41-45.

 

Linhart Y. B. 1976. Density-dependant seed germination strategies in colonizing versus non-colonizing plant species. J. Ecol. 64 : 375-380.

 

 Linhart Y. B. and R. A Pickett. 1973. Physiological factors associated with density-dependent seed germination in Boisduvalia glabella  (Onagraceae). Z. Pfianzenphysiol. 70 : 367 - 370.

 

Pandey H. N. and S. K. Dubey. 1989. Growth and population dynamics of an exotic weed Parthenium hysterophorus. L. proceedings of Indian Academy of Sciences (Plant Sciences) 99 : 51-8.

 

Rai J. P. N. and Tripathi R. S. 1983. Population regulation of Galinsoga ciliata and G. parviflora : effects of sowing pattern, population density and soil moisture and texture. Weed Research 23 : 151-63.

 

Rai J. P. N. and Tripathi R. S. 1984. Population dynamics of  different seedling cohorts of two co-existing annual weeds, Galinsoga ciliata and G. parviflora, on two contrasting sites. Acta, Oecologia Plantaram 5 : 357-68.

 

Rutgers Cooperative Extension. 1999. Cook College, 88 Lipman Drive, New Brunswick, NJ 08901-8525.

 

Schwaegerle K. E. and D. A. Levin. 1990. Environmental effects on growth and fruit production in Phlox drummondi. Joiurnal of Ecology 78 : 15-26.

 

Terry P. J., and R. W. Michieka. 1987. Common Weeds of East Africa. Food and Agriculture Organization of the United Nation, 00100 Rome, Italy.

 

Usami Y. 1976. Ecological studies on weeds in Mulberry fields. 2. Autecology of Galinsoga parviflora Cav. Weed Research 21: 76-80.

 

Warwick S. I. and R. D. Sweet. 1983. The biology of Canadian weeds. 58. Galinsoga parviflora and G. quadriradiata (= G. ciliata). Can. J. Plant Sci. 63 : 695-709.

 

6) Weed management

 

6.1) Chemical control

 

Belinda R. R., R. W. Wallace and G. L. Jordan. 1997. English pea (Pisum sativum) tolerance to paraquat and paraquat plus bentazon. Weed Technol. 11:39-44.

 

Beste. C. E. 1973. Evaluation of herbicides in no-till planted cucumbers, tomatoes, and lima beans. Northeast. Proc. Weed Sci. Soc. 7:232-239.

 

Bhowmik P. C. and E. N. McGlew. 1986. Effects of oxyfluorfen as a pretransplant treatment on weed control and cabbage yield. J. Am. Soc. Hort. Sci. 111;686-689.

 

Campbell W. F. and J. L. Anderson. 1980. Effects of no-tillage and herbicides on carrot and onion seed production. Hort. Sci. 5:662-664.

 

Chi-Chu, W. C., Shing-Shing, and T. Jiuun-Shyong. 1975 Experiments on single and mixed application of herbicides in grain sorghum. Mem. Coll. Agric. Nat. Taiwan Univ. 16: 1-14.

 

Coolman R. M. and G. D. Hoyt. 1993. The effects of reduced tillage on the soil environment. Hortic. Technol. 3:143-145.

 

Danielson L. L., W. B. Ennis, D. L. Klingman, W. C. shaw, F. L. Timmons, J. E. Jernigan, J. R. Paulling, and P. E. Strickler. 1965. A survey of extent and cost of weed control and specific weed problems. USDA Crops Res. Bull., ARS 34-23-1: pp 78.

 

Fernald, G. 1970. Gray’s Manual of Botany. D. van Nostrad Co.,N. Y., pp 1632.

 

Frankton C. and G. A. Mulligan. 1970. Weeds of Canada. Can. Dep. Agric. Publ. 948: pp 217. 

 

Hartfield H. H., D. T. Warholic and R. D. Sweet. 1978. Dinitroaniline toxicity of Galinsoga, ragweed, and several crops. Proc. Northeast. Weed Sci. Soc 32 : 141-150.

 

Hughes B. J. and R. D. Sweet. 1978. Weed science results. Vegetable crops department, Cornell University.

 

Ivany J. A. 1971. Galinsoga ciliata and Galinsoga parviflora : Germination, growth, development and control. Ph.D. Thesis, Cornell University. 164 pp.

 

Jansen L. L., L. L. Danielson, w. B. Ennis, P. A. Frank, J. T. Holstun, D. L. Klingman, J. R. Paulling, R. a Wearne and A. S. Fox. 1972. Extent and cost of weed control with herbicides and an evaluation of important weeds 1968. USDA-ARS Publication H-1:

 

McLaughlin M. and R. D. Sweet 1974. Weed Science results. Vegetable crops department, Cornell University.

 

Mohammed E. S. and R. D. Sweet. 1976. Weed science results. Vegetable crops department, Cornell University.

 

Romanowski R. R. and H. D. Fulmer 1971. Research results and suggested control of Cincinnati weed (galinsoga spp.) in vegetable crops. Veg. Crops mimeo 71-72. Horticulture Department, Perdue university.

 

Rutgers Cooperative Extension. 1999. Cook College, 88 Lipman Drive, New Brunswick, NJ 08901-8525.

 

Sanok W. J., G. w. Selleck and j. f. Creighton. 1979. Evaluation of herbicides for weed control in onions. Proc. Northeast Weed Sci. Soc. 33:154-156.

 

Sanok, W. J. and G. W. Sellek. 1978. Herbicide candidates for weed control in onions. Proc. Northeast Weed Sci. Soc. 32:134-136.

 

Stilwell E. K., and R. D. Sweet 1975. Galinsoga control in cabbage and broccoli. Proc. Northeast. Weed Sci. Soc: 239-43.

 

6.2) Non-chemical control

 

Bellinder R. R. 1990. Alternative weed control programs for snap beans. Proc. Northeast. Weed Sci. Soc. 44:69.

 

Bellinder R. R. 1995. Snap Bean Growers Weed Management Survey. pp 5.    

 

Doss B. D., J. L. Turner and C. E. Evans. 1981. Influence of tillage, nitrogen, and rye cover crop on growth and yield of tomatoes. J. Am. Soc. Hort. Sci. 106:95-97.

 

Hoyt G. D. 1984. The effect of cover crops in strip-till vegetable and tobacco production. Proc. Soil Sci. Soc. North Carolina 27:10-20.

 

Hoyt G. d. 1993. Conservation tillage for Burley Tobacco Information. N. C. Cooperative Extension Publication. AG 376.

 

Ivany J. A. and R. D. Sweet. 1973. Germination, growth, development and control of Galinsoga. Weed Science 21:41-5.

 

McKeown A. W., R. F. Cerkkauskas, and J. W. Porter. 1988. Influence of strip tillage on yield, diseases and nematodes of tomatoes. J. Am. Soc. Hort. Sci. 113:328-331.

 

Mullins C. A., R. A. Straw and D. L. Coffey. 1988. Production of snap beans s affected by soil tillage method row spacing. J. Am. Soc. Hort. Sci. 113:667-669.

 

Peterson K. L., H. J. Mack and D. E. Booster. 1986. Effect of tillage on sweet corn development and yield. J. Am. Hort. 111:39-42.

 

Standifer L. C. and C. E. Beste. 1985. Weed control method for vegetable production with limited tillage. Weed Sci. Soc. Am. Monogr. No. 2. pp 93-100.

 

Tessore C. M., W. E. Chappell, R. D. Morse and C. R. O’Dell. 1981. No-till fall vegetable experiments. The Vegetable Growers News (VPI) 35:2-3.

 

University of Connecticut - IPM Extension. 2000. Http://www.cla.lib.ct.us/canr/ces/ipm/weeds/htms/galnsoga.htm

 

Wilhoit J. H., R. D. Morse and D. H. Vaughan. 1990. Strip-tillage production of summer cabbage using high residue levels. Appl. Agric. Res. 5:338-342.

 

7) Usage and properties

 

Batra S. W. T. 1979. Insects associated with weeds of the Northeastern United States: Quickweeds,  and G. parviflora (compositae). Environ. Entomol. 8 : 1078-1082

 

Stubbendieck J., G. Y. Friisoe., M. R. Bolick. 1995. Weeds of Nebraska and the Great Plains. Nebraska Department of Agriculture. PO Box 94756. Lincoln, Nebraska-Lincoln.

 

8) Genetic Studies

Canne J. M. 1977. A revision of the genus Galinsoga (Compositae : Heliantheceae). Rhodora 79 : 319-389.

 

Gopinathan M. C. and C. R. Babu. 1982. Cytogenetics of Galinsoga parviflora Cav. and G. ciliata (Raf.) Blake and their natural hybrids (Asteraceae). New Phytol. 91 ; 531-539. 

 

9) Other Topics

 

Harper J. L. 1977. The population Biology of Plants. Academic Press, London and New York.

 

Ivany J. A. 1971. Galinsoga ciliata and Galinsoga parviflora : Germination, growth, development and control. Ph.D. Thesis, Cornell University. 164 pp.

 

Ivany J. A. 1975. Today’s weed: Galinsoga. Weeds Today 6 : 22.

 

Misra R. 1968. Ecology Work Book, pp 332-33. Oxford and IBH, New Delhi.

 

Rai J. P. N. and R. S. Tripathi. 1983. Population regulation of Galinsoga ciliata and g. parviflora. Weed Research. 23 : 151-163.

 

White J. and J. L. Harper 1970. Correlated changes in plant size and number in plant populations. J. Ecol. 58 : 467-485.

 

Yoda K.,  J. Kira, H. Ogawa and K. Hozumi. 1963. Self-thinning in over-crowded pure stands under cultivated and natural conditions. J. Biol. Osaka City Univ. 14 : 107-129.

 

Zar J. H. 1974. Biostatistical analysis. Prentice Hall of International Inc., New Jersey.