Insect Sci. Applic. Vol. 12, No. 4, pp. 347-359, 1991 0191-9040/91 $3.00 + 0.00 Printed in Kenya. All rights reserved © 1991 ICIPE—ICIPE Science Press STATUS OF BIOLOGICAL CONTROL OF PARTHENIUM HYSTEROPHORUS L. IN INDIA: A REVIEW J. SRIKANTH and N. A. PUSHPALATHA Department of Entomology, University of Agricultural Sciences, G. K. V. K. Campus Bangalore 560 065, India (Received 15 August 1989; revised 7 May 1990) Abstract—Biological control efforts on Parthenium hysterophorus L. (Asteraceae) in India have gained momentum after the limitations of other methods were realized. Native surveys revealed a large number of insects, but none of them was host specific. Although the introduced beetle Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) has established at the sites of initial releases, its real impact on the weed and performance in different parts of the country need further evaluation. Fungal pathogens of the weed hold promise for classical as well as microherbicidal control. The use of parthenium phyllody MLO as a biocontrol agent requires establishment of host and vector specificity. Mycotoxins are a potential group of herbicides on which serious studies are yet to begin. Studies on control of the weed through interference and allelopathy by Cassia uniflora Mill. (= C. sericea Sw.) (Leguminosae) have produced promising results. Toxic leachates of C. uniflora and autotoxic principles of the weed deserve attention. Integrated biocontrol strategies envisaged for wastelands using introduced insects and pathogens, allelopathic plants, and agroecosystems using native pathogens, mycotoxins and autotoxic principles, will help combat this apparently invincible weed. Key Words: Parthenium hysterophorus, biological control, Zygogramma bicolorata, mycotoxins, allelopathy, Cassia uniflora Resume*—Les efforts contrdle biologique sur Parthenium hysterophorus L. (Asteraceae) en Inde se sont accel6res des qu'on s'est rendu compte des limites des autres methodes. Des recherches locales ont revele un grand nombre d'insectes mais aucune d'el les n'etaient un note splcifique. Malgre que le coleoptere Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) recemment introduit se soit etabli sur des sites ou on l'a initialement e~leve~, son impact reel sur I'ivraie et le resultat obtenu dans d'autres regions du pays necessite une plus ample evaluation. Les microbes pathogenes fongaux de I'ivraie donnent une lueur d'espoir tant pour le contrdle classique que pour le contrdle microherbicidal. L'utilisation de la phyllodie du parthenium MLO comme agent biocontrole exige la connaissance de la specificity de l'hdte et du vecteur. Les mycotoxins sont un groupe potentiel d'herbicides sur lesquels on doit commencer des etudes serieuses. Les etudes sur le contrdle des mauvaises herbes au moyen d'interference et d'allelopathie par la plante Cassia uniflora Mill. (= C. sericea Sw.) (Leguminosae) ont donne1 des resultats prometteurs. Les extraits toxiques du C. uniflora et des principes autotoxiques de mauvaises herbes merite une attention particuliere. Les strategies inte'gre'es du biocontrole envisagees pour des terres en friche en utilisant des insectes et des pathogenes introduits, des plantes alleiopathiques, et, peur des agro- ecosystemes, ('utilisation des pathogenes indigenes, des principes mycotoxins et autotoxiques aideront a combattre cette mauvaise herbe apparemment invincible. 347 348 J. SRIKANTH and N. A. PUSHPALATHA INTRODUCTION employment of polyphagous insects, mycotoxins and MLO diseases, to the more serious efforts Very few weeds in India have generated as much made to import and release exotic natural enemies alarm and concern among the scientific for classical biological control. community and common man as the weed Parthenium hysterophorus L. (Asteraceae). Insects and mites Native to Mexico, the weed, within the last 100 years, has found its way to Africa, Australia and An examination of the list of insects and mites Asia, and currently enjoys worldwide distribution reported on this weed in India (Table 1) reveals (Haseler, 1976; Towers et al., 1977). Although it many of them to be polyphagous pests of was first noticed in India in the year 1956 (Rao, agricultural crops. Although many were noticed 1956), its actual date of entry into the country was as sporadic occurrences causing minor damage, a traced back to 1810 by Bennett et al. (1978) and few occurred in serious proportions often killing confirmed by Maiti (1983). Also popularly called the plant. broom-bush, carrot weed, congress grass, white Amongst the four species of scale insects top, etc., its spread to different parts of the country found attacking the stems and branches, has been very rapid. According to Krishnamurthy Parasaissetia nigra (Nietn.) and Saissetia coffeae et al. (1976), about 2 M ha of land is covered by (Wlk.) caused wilting of parthenium plants in the this weed in the country. However, the weed glasshouse, while P. nigra often killed groups of remained in obscurity for about a decade after its the weed in the field (Kumar et al., 1979). discovery and rose to prominence only after its Similarly, the lantana scale, Orthezia insignis hazardous effects on the lives of people reached Browne, attacked the stem, leaves and flowers of intolerable levels. The interference of this weed in the weed in dense colonies in summer, resulting in agriculture (Vartak, 1968; Kanchan and the wilting and drying of a few plants (Srikanth et Jayachandra, 1976) and animal health al., 1988a). (Narasimhan et al., 1977) has been well Adults and nymphs of the membracid demonstrated. Its distribution, chemistry, hazards Leptocentrus taurus F. attacked the main stem, and control have been extensively reviewed petioles and bases of midribs of about 20% of the (Krishnamurthy et al., 1977; Towers et al., 1977; more than 1000 plants examined (Thangavelu, Basak, 1984; Parihar and Kanodia, 1986; Joshi, 1980). 1990). Several species of mealy bugs were reported Although several methods have been proposed on this weed. Ferrisia virgata (Ckll.) attacked for the suppression of this weed, each has its own especially the roots of young plants which wilted disadvantages (Joshi, 1989). For instance, and dried (Char et al., 1975). Potted plants of the mowing the weed as soon as it flowers, though weed when infested with Planococcus sp. wilted preventing seed production, results in rapid within a week without producing a single seed regeneration of new shoots necessitating repeated (Hegde and Patil, 1979). Similarly, Icerya operations (Gupta and Sharma, 1977). seychellarum (Westw.) killed the weed in the Mechanical uprooting is constrained by the glasshouse, whereas F. virgata when reared and development of dermatitis in workers engaged in released on isolated patches of the weed failed to the operation (Krishnamurthy et al., 1977). kill the latter (Kumar et al., 1979). Chemical control, though effective, is temporary Larvae of the beetle Oberea sp., and grubs and and needs repeated application, besides having adults of the scolytid Hypothenemus eruditus problems of residues, selectivity and cost of (Westw.) were found boring into the stems application. Moreover, it is rather impossible to causing wilting and death of the plants. As many adopt these methods in vast stretches of as 15-20 adults of the latter were seen in a single wasteland. These disadvantages prompt us to plant besides many grubs, and up to 75% of the include biological methods as a component of plants were bored in some areas (Kumar et al., parthenium control programme. In the present 1979). Adults of the flea beetle Luperomorpha paper we review the status of biological control of vittata Duvivier caused characteristic P. hysterophorus in India and discuss its future in skeletonized spots on leaves by scraping the light of several available and potential tools for epidermis. They also fed on stems by scraping the integrated biological control programme. epidermis and scooping the cortex portion The studies made so far in this regard ranged (Srikanth et al., 1991).Larvae of Spilosoma from surveys conducted for natural enemies and obliqua Wlk. voraciously fed on leaves and main Biological control of Parthenium hysterophorus L. 349 Table 1. Insects and mites recorded on P. -hysterophorus in India Order Family Species Reference Heteroptera Pentatomidae Chrysocoris stollii (Wolff) Kumar et al. (1979) Dolycoris indicus Stal Kumar et al. (1979) Homoptera Aphididae Aphis gossypii Glov. Rajendran (1976), Krishnamurthy et al. (1977), Kumar et al. (1979), Raodeo and Tayade (1979), Keshwal (1982) Aphis spiraecola Patch Rajendran (1976) Cicadellidae Aconurella sp. Mathur (1989) Batracomorphus angustatus (Osborn) Ravi (1983), Mathur (1989) Batracomorphus indicus (Lethierry) Mathur (1989) Empoasca sp. Mathur (1989) Empoasca devastans Distant Padmanabhan (1982) Exitianus indicus (Distant) Mathur (1989) Hecalus arcuatus (Motschulsky) Mathur (1989) Hishimonus phycitis (Distant) Padmanabhan (1982), Mathur (1989) Leofa sp. Mathur (1989) Orosius albicinctus Distant Keshwal (1982), Anantha Murthy (1984), Mathur (1989) Thaia sp. Mathur (1989) Coccidae Ceroplastes sp. Kumar etal. (1979) Coccus longulus (Dgl.) Kumar etal. (1979) Parasaissetia nigra (Nietn.) Kumar etal. (1979) Saissetia coffeae (Wlk.) Kumar etal. (1979) Margarodidae Icerya seychellarum (Westw.) Kumar etal. (1979) Membracidae Coccosterphus minutus (F.) Kumar et al.( 1979) . Leptocentrus taurus F. Thangavelu (1980) Oxyrhachis tarandus (F.) Kumar etal. (1979) Telingana campbelli