International Journal of Advances in Science Engineering and Technology, ISSN: 2321-9009, Vol-5, Iss-3, Spl. Issue-2 Sep.-2017 http://iraj.in INVASIVE SPECIES MICRANTHA AN ENVIRONMENTAL THREAT, ITS CONTROL WITH REFERENCE TO ERI SILK WORM

MAINU DEVI

Department of Zoology, Diphu Govt. College Affiliation : Assam University, silchar, Assam, E-mail: [email protected].

Abstract: Biological invasion is one of the three most difficult environmental problem in the world. The control of invasive species is one of the most urgent challenges in ecology today. kunth ex H.B.K. is one of the 100 world’s worst alien species and pose a serious threat to biodiversity and ecosystem. Mikania has been shown to have allelopathic properties that can inhibit the growth of . Mechanical control method of Mikania are labour intensive, expensive and not effective in longer term. Efforts has been made to use biological control mechanism to sustainably manage Mikania. According to the information provided by the Silk worm rearers Mikania micrantha is used by a sizable Eri Silk rearers in Karbi Anglong District of Assam, India for want of host plants , particularly at the latter larval stages when the larva starts to eat voraciously. In this paper the nutrient contents of Mikania micrantha and the impact of feeding Mikania micranhta and Ricinus communis ( The primary food ) on silk quality parameter (denier, tenacity, elongation at break and defective cocoon) of eri silk worm, Samia ricini Donovan have been investigated. Significantly finer denier (1.786±0.070), higher breaking strength or tenacity (3.590±0.150) and lower percentage of elongation at break (24.029±1.557) were recorded in the larvae fed with Mikania leave from III instar till maturity. No defective cocoons were recorded in any case under the laboratory condition conducted under investigation. The equality parameters in Mikania micrantha and Ricinus communis examined by student t- test subscribes the view that moisture (70.90%), ash (12.54%),Calcium (1.63%), and phosphorus (0.57), are significantly higher in Mikania micrantha while the percentage of nitrogen (3.64%), crude protein (22.86%), and crude carbohydrate (33.27%) on dry weight basis in Mikania micrantha did not differ significantly with Ricinus communis (nitrogen : 3.66% ; protein : 22.85% and carbohydrate: 34.30%). Thus Mikania micrantha a commonly available weed all over can be commercially exploited for better growth, development and silk yield of Samia ricini Donovan. Exploitation of Mikania micrantha to this end would also help in controlling its spread to new regions and conserve biodiversity.

Key Words: Mikania micrantha, Invasive species, Biodiversity, Biological control, Samia ricini.

I. INTRODUCTION reproduces from broken stem fragments. Waterhouse and Mitchell (1998), reported that Mikania Biological invasion is one of the major threats to micrantha interferes with soil nitrification process native Biodiversity and Ecosystem. Mikania and also reduces the carrying capacity of pastaur. micrantha ex H.B.K. (Fig1a), commonly known as In Australia Mikania has been declared a class 1 Bitter Vine, a perennial weed of the Order , weed in Queensland under the Rural Land Family , has been listed as one of the 100 Protection Act. Mikania has also been worst invasive alien species in the world (Lowe et consistently ranked amongst the top three worst al.2001). It is known for its vigorous and rampant weed by member countries of the Secretariat of growth grows best where fertility , organic matters the Pacific community (SPC). Mikania causes a , moisture, humidity are all high. It is known by major menace in natural forests, agricultural different names in different parts of the world; systems specially tea , rubber and other plantation American rope, Chinese creeper and Mile-a-minute in crop in North East and Southwest India (Sankaran English ;Japani Habi in India; Chinesischer and Sreenivasan, 2001). Mikania debris Sommerefeu in German ; Liane americaine in French incorporated into soil was also shown to inhibit ; Ovaova in Fijian etc. It occurs in agricultural areas, germination and seedling growth in some crops. coastland, natural forests, shrubs lands, urban areas, According Pacific Island Ecosystem at Risk wetlands etc. Once established M. micrantha can (PIER) information much of the works on Mikania have a major impact on natural ecosystems, in has been carried out on its eradication and particular forest communities (Fig1b). This species biological control. Various Bio-control projects can smother native vegetation, eventually killing against this weed have been carried out since many plants including trees, decreasing 2002 by the National Agricultural Research biodiversity. A native of Central and South Institute (NARI) and Cocoa Research Institute. America, Maxico and it was Studies on Mikania has been shown to have introduced into India after the II World War to allelopathic properties i.e. releases chemicals that camouflage airfields and is one of the most can inhibit the growth of plants. Li-ying, Guang- widespread and problematic weeds in the Pacific Yan, Chen, Peng and Li- Flanglan (2007), while region. The seeds are dispersed by wind or in studied on energetic cost of Mikania micrantha leaves clothing or hair of animals. Vegetatively it observed that a variety of secondary metabolites like

Invasive Species Mikania Micrantha An Environmental Threat, Its Control With Reference To Eri Silk Worm

7 International Journal of Advances in Science Engineering and Technology, ISSN: 2321-9009, Vol-5, Iss-3, Spl. Issue-2 Sep.-2017 http://iraj.in Phenolics, Flavonoids, Alkaloids and Terpens can be II. MATERIALS AND METHODS released by volatilization, lixiviation of aerial parts and decomposition of plant debris in the soil. The 2.1) Nutrient contents of Mikania micrantha. investigatory works of Singh and Benchamin (2002) The healthy leaves of Mikania micrantha were on various botanicals suggest that many secondary collected from in and around of Diphu town and after metabolites such as phenolics, Glycocides, Alkaloids, estimating the moisture contents using electronic Terpenoids, etc. that occur in plants exhibiting moisture analyzer (Startorius, model MA35) the leaf variation in quality as well as quantity operating as samples are shade dried for three days. The dried specific olfactory and gustatory stimuali. It is further samples were transferred to hot air oven at 70ºC until established that the weed plants such as Cassia tora, constant weight was obtained. The samples were Lantana camara, Clerodendron inermae, Tribulus ground into fine powder and preserved in butter paper terrestris, etc. release these metabolites and are being bags for chemical analysis according to the following tried to increase the silk and egg production in method. Mulberry silk worm Bombyx mori as well as Eri silk worm, Samia cynthia ricini Bois. At lower Total nitrogen was estimated by Microkjeldahl concentrations these secondary metabolites increase method. ; Crude protein was derived using the factor the larval and cocoon characters and thereby silk %N X 6.25;Total carbohydrate was estimated using yield in both eri and mulberry silkworm ( Mane and the method of Dubios et al., (1956); Crude fat was Patil, 2000). These metabolites have stimulatory determined from an oven dried sample using a effect on protein synthesis in the silk gland during Soxhlet extraction apparatus (AOAC, 1970); Ash was larval period , thus leading to the increased silk determined by the AOAC, 1970 method; output in Eri and Mulberry silkworm . The leaves of Phosphorous content was determined weed plant Mikania micrantha had been found to Spectrophotometrically using UV VIS have significant effect on qualititave parameters of eri Spectrophotometer 118; Iron content was determined silk worm, Samia ricini Donovan while feeding the by Spectrophotometrically using UV VIS Eri silk worm castor leaves fortified with its extracts Spectrophotometer 118; Calcium content was (Devi , M., 2010). Keeping all this in view the determined according to AOAC, 1970. present study has been undertaken to know the nutrient contents of the invasive splecies Mikania All the estimation was done on dry weight basis in micrantha and the effect of its feeding on quality triplicate and the mean was recorded and compared parameter (Denier, Tenacity, Elongations and with analyzed data of nutrient contents of castor Defective Cocoon percentage) of silk fibre of Eri leaves. Silkworm Samia ricini Donovan. 2.2) Silk Quality of Eri Silk worm Fresh disease free layings (dfls) of Eri silkworm were reared in the laboratory at temperature 22 ± 3 and 78 ± 4% RH. The egg incubation and rearing were undertaken as per the recommended method of Choudhury (1982 ). Four experimental treatments were developed with different food plants of Mikania micrantha and Ricinus communis ; Experimental tr-I- (Host plant Mikania micrantha); Experimental tr- II ( Host plant Ricinus communis from I to IV instar larvae. The V instar larvae fed with Ricinus communis and M. micrantha in Fig 1b. Mikania micrantha decreasing equal proportion) ; Experimental tr-III ( Host plant plant Ricinus communis from I to II instar larvae. III instar larvae fed with Mikania micrantha till maturity). Experimental tr-IV( Host plant Ricinus communis considered as control). The Physical characteristics of silk fibre such as Denier, Tenacity, Elongations and Defective cocoon percentage were calculated and subjected to statistical analysis.

III. RESULTS AND DISCUSSIONS

The equality parameters in Mikania micrantha and Ricinus communis examined by student t- test is presented in Table1and Fig 2 subscribes the view that Fig 1a: The invasive plant Mikania micrantha.Biodiversity of Natural forest. moisture (70.90%), ash (12.54%),Calcium (1.63%),

Invasive Species Mikania Micrantha An Environmental Threat, Its Control With Reference To Eri Silk Worm

8 International Journal of Advances in Science Engineering and Technology, ISSN: 2321-9009, Vol-5, Iss-3, Spl. Issue-2 Sep.-2017 http://iraj.in and phosphorus (0.57), are significantly higher in moisture a primary determining factor, influencing Mikania micrantha ( P<0.01),while the percentage of the other biochemical nutrients affects the growth of nitrogen (3.64%), crude protein (22.86%), and crude silkworm larvae (Narayanaprakash et. al. 1985 ). carbohydrate (33.27%) on dry weight basis in Eri silkworm reared on Mikania micrantha, Ricinus Mikania micrantha did not differ significantly with communis and their combination have profound Ricinus communis (nitrogen : 3.66% ; protein : effect on the silk quality parameter (Denier, Tenacity 22.85% and carbohydrate: 34.30%) or they were and Elongation at break). Significantly finer denier statistically at par. Thus, it is evident that the nutrient (1.786±0.070), higher breaking strength or tenacity contents of weed plant Mikania micrantha and (3.590±0.150) and lower percentage of elongation at Ricinus communis, the primary food plant of Eri silk break (24.029±1.557) were recorded in the larvae fed worm are identical.In the present investigation of with Mikania leave from III instar till maturity as biochemical study on Mikania leaves revealed the shown in Table 2. Finer silk fibres have higher occurrence of quite a significant concentration of breaking strength and lower percentage elongation at major and micronutrients which could have break (Rajkhowa, 2000). It is also established fact accelerated the growth and development of Eri silk that lower the single cocoon filament denier, better is moth and thereby the silk output. It is very well the quality of cocoons (Vasumathi, 2000). A lower established fact that the moisture plays a very denier implies finer silk filament and hence is more important role in the development of silkworm. Leaf desirable. Table 1: Nutrient contents of Mikania micrantha and Ricinus Communis.

**Significant at P (<0.01) ; NS : Not Significant

Table-2 Silk quality parameter of eri silkworm Samia ricini Donovan reared on Mikania micrantha, Ricinus communis and their combination.

Invasive Species Mikania Micrantha An Environmental Threat, Its Control With Reference To Eri Silk Worm

9 International Journal of Advances in Science Engineering and Technology, ISSN: 2321-9009, Vol-5, Iss-3, Spl. Issue-2 Sep.-2017 http://iraj.in

The finer silk filament may be attributed to the [3] [3] E.IIzuka, ‘Physical properties of silk thread from increased protein synthesis particularly the fibrion cocoons of various wild silk-moth including domestic silkmoth’. Int. J. wild silkmoth & silk. 5 : 266-269, 2000. synthesis in the posterior silk gland of Eri Silk Worm [4] [4] G.H. Santosh kumar, Rajasekhargouda and Mane, which in turn influences the fibre fineness. These ‘Effect of dusting some plant products on quantitative and findings are in conformity with the findings of qualitative characters of Mulberry silk’. Bull. Acad. Ser 4(1) Santoshkumar, Rajashekharagouda and Mane (2000), 75-77,2000. [5] [5] J.R. Mane, G.M.. Patil, ‘Effect of botanicals having IGR who obtained lowest denier produced by the activity on growth & development and economic Eri Silk silkworm fed with mulberry leaves dusted with weed worm, Samia Cynthia ricini boisd’. International Journal of plant Lantana camara. Further, in the present wild silkmoth and silk, 5 : 200-203,2000. investigation no defective cocoons in any case under [6] [6] K.Singh, Chaoba and K.V. Benchamin , ‘A Bibliography on ericulture. Central Muga and Eri Research laboratory condition were noticed which further & Training Institute, Jorhat, Assam. Eri Silk worm, Samia proved better quality of cocoons, hence, better quality Cynthia ricini boisd’. International Journal of wild silkmoth of silk fibre produced by Eri silkworm at different and silk, 5 : 200-203,2000. treatments. [7] [7] K.V.Sankaran, M.A. Sreenivasan, ‘Status of Mikania infestation in the western ghat’. In: K.V.Shankaran, S.T. Murphy, H.C. Evans, eds. ‘Allien weeds in moist tropical CONCLUSION zones, bans and benefits’, Kerela Peechi, India. Kerela Forest Research Institute. Pp.67-76,2001. The above observations have indicated that foliar [8] [8] Li-ying, N.Guang-Yan, B.M Chen and S.L. Peng, ‘Energetic cost of leaf construction in the invasive weed constituents of Mikania micrantha have a strong Mikania micrantha H.B.K. and its co-occurring species’. bearing on quality of silk fibre of Eri silkworm and Botanical studies, 48 : 331-338,2007. thus, it can be exploited for increasing the silk [9] [9]. M. Devi, ‘An Investigation on growth development and production commercially. As the mechanical control yield of silkworm Samia ricini reared on Castor and Japanese weed in Karbi Anglong District’. Ph.D. Thesis, method of Mikania are labour intensive, expensive Gauhati University, Assam (India),2010. and not effective in longer term the biological control [10] [10] R. Narayanaprakash, K. Periaswami and S. mechanism can help in controlling its spread to new Radhakrishnan,, ‘ Effect of dietary water content on food regions and conserve biodiversity. utilization and silk production in Bombyx mori L. (Lepidoptera : Bombycidae)’. Ind. J. Seric. 24 : 12-17,1985. [11] [11] R. Rajkhowa , ‘Structure property correlation of non- REFERENCES mulberry and mulberry silk fibre’. International J. of Wild Silkmoth. Vol. 5: pp 287-298,2000. [1] [1] B.V. Vasumathi, ‘An analytical study of the silk reeling operation in Karnataka’, Ph.D. Thesis, Indian Institute of [12] [12] S. Lowe, M.Brown, S.Boudjelas, and M. De Poorter, Science, Bangalore, 2000. ‘100 of World’s Worst Invasive Alien Species: A selection [2] ]2] B.M. Waterhouse, A.A. Mitchell, ‘Nothern Australia from the Global Invasive Species’ Database. The Invasive Quarantine Strategy : weeds target list’. Second edition. Species Specialist Group (ISSG) 12PP,2001. Australian Quarantine & Inspection Service, Miscellaneous [13] [13] S. N.Chaudhury, Eri Silk Industry, published by Publication NO.6/98,1998. Directorate of Sericulture& Weaving, Govt. of Assam, pp. 16-114, 1982. 

Invasive Species Mikania Micrantha An Environmental Threat, Its Control With Reference To Eri Silk Worm

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