Effect of Starvation on the Biochemical Moieties and ...

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Starvation has an adverse effect on survival of third instar grubs of Leucopholis lepidophora. Bl. Third instar grubs when starved for 45 days it causes loss in ...
J.Shivaji Univ.(Science & Technoiogy)39,(2004-2005),41-45

Effect of S t a r v a t i o n on the Biochemical Moieties and Haemolymph Constituents of Third Instar Grubs of Leucopholis Lepidophota Bl (Coleoptera:Scarabaeidae) G. P. B H A W A N E 1 , S.B. PATIL 2 , D. S. NIKAM 3 AND S. R. W A G H 4 ABSTRACT: Starvation has an adverse effect on survival of third instar grubs of Leucopholis lepidophora Bl. Third instar grubs when starved for 45 days it causes loss in body weight upto 2 1 % . Bjochemical moieties like total sugars, glucose, proteins and lipids get considerably reduced "by 26%, 49%, 24% and 83% respectively due to starvation. The total haemocile count (THC) of starved grubs increased from ISSO/mm^ of haemoloymph to 3850/mm^ of haemolymph. The cationic composition of haemolymph also get affected due to starvation. The Na* ion concentration get increased by 13% and composition of cations like K+, C a + , M g ' get decreased by 28%, 22% and 14% respectively during starvation. The haemolymph total sugar, glucose and protein content in starved grubs also reduced by 79%, 100% and 63% respectively.

INTRODUCTION : Starvation Is one of the type of environmental stress that insects may be exposed during their growth and development. Sensitivity of an insect to starvation may be used as a measure of the nutrient energy stored during it's feeding period. Those insects will survive starvation best, that have large amounts of energy stored or have a low energy requirement over and extended period. Life expectancy of starved adult beeetles is known to be affected by age and sex (Ducoff e/.a/.,1970) and by temperature (Simwat & Chahat, 1969). The role of starvation as an aspect of nutritional disease (House, 1963; Shapiro, 1965) have done extensive work on the effects of starvation on lepidopteran larvae, Galleria mellonella. Effect of starvation on the weight loss, percent dry weight, total haemolymph solids, total proteins, total haemocytes, total glucose and trehalase were studied in the tobacco hornworm Manduca sexta by Dahlman, 1973 (a and b) and in Locusfa by Mwangi and Goldswirthy,(1977) and by Justum et.al. (1975). Considerable information has been collected on haemolymph constituents and their concentration In many insects (Wyatt, 1961). Development fluctuation of metabolites and enzymes has been extensively examined in several species (Hudson, 1966; Crompton & Birt, 1967; Schmidt and Mathur, 1967; Tripati and Dixon, 1968). The total haemocyte count (THC) 1'

Corresponding Author.

1 Departmant of Zoology, Shivaji University, Kolhapur - 416 004.(Maharashtra) 2 Department of Zoology, Hutatma Rajguru Mahavidyalaya, Rajgurunagar, Dist. Pune, (Maharashtra) 3 Department of Zoology, D.A.B.N. College, Chikhali, Dist. Sangli. (IWaharashtra) 4 Department of Zoology, New Arts, Commerce and Science College, Pamer, Dist - Ahmednagar, (Maharashtra)-414 302.

get significantly increased due to starvation in Leptinotarsa (Aryy et.al., 1948) and in Prodenia (Rosenberger & Jones, 1960). JUe fpssorial grubs of Leucopholis lepidophora 61. have assumed the status of serious polyphagous pest darnaging roots of various crop, it damages the sugarcane which being the major crop in tlie fields situated on the banks of Kumbhi-Kasari and other rivers of south western parts of the Kolhapur District oi Maharashtra, India. Monoculture of sugarcane provide the perennial source of food and other essential condition for the multiplication and spread of pest. Our personal observation indicates that these grubs are hardy to the rehydration in the field as well a^ under laboratory condition (Disale et.al.. 1943). These grubs are hardy to the temporary condition of depletion of food for a period of 3 months in the field and the same is experienced under laboratory condilion. Therefore, it has been decided to study the effects of starvation on the biochemical moieties and haemolymph constitutents of third instar grubs of Leucopholis lepidophora E\.

MATERIAL AND METHODS : Third instar grubs of Leucopholis lepidophora Bl. were collected from the infested sugarcane fields o( Sangrool of Kolhapur District, Maharashtra, India in the month of November. The grubs collected from the particular field were of same age and having more or less similar weight. The grubs were brought to the laboratory and maintained in the earthen pots filled with adequately moistened soil (about 25% moisture) obtained from the same field. The grubs were previded with roots of paddy and potato as a food. Two groups, each containing 15 grubs were kept in separate earthern pots. The earthern pots containing adequately moistened soil about 25% serves as a control and the food is regularly supplied to them served as control. The • earthen pots containing moistenedsoil and the grubs were subjected to starvation for a period of 45 days served as experimental group. After 45 days of starvation the average weight of control and experimental starved larvae were taken (or the determination of loss in body • weight. For the determination of body total reducing sugar and proteins 5 larvae were horriogenized in 1 N NaOH after removing the rectal content. The homogenate was centrifuged at 2000 rpm tor 10 minutes. The supernatant was used for the determination of total body proteins by using Biuret's reagent (Gornell et.al., 1949) and by using 3, 5 dinitrosalicilic acid reagent (Bernfield, 1955) was used for the determination of total reducing sugars. For the determination of glucose homogenates of 3 control and 3 starved grubs were prepared in the distilled water separately centrifuged at 2000 rpm for 10 minutes. The supernatant were used to determine the glucose content by using glucose peroxidase reagent from Span Diagnostic Limited. For the determination of total lipids of control and starved grubs Folch's mixture {Folch et.ai, 1957) was used for the extraction and (Barnes and Blackstock, 1973) method was used for the quantitative determination of lipids. Above methods were also used for estimation of total sugar, glucose and protein from haemolymph of starved and control grubs. The total haembcyte counts of the control and starved grubs were made with the help of Neubauer's haemocytometer by using 2% versene ringer as a dilution fluid (Resenberger and Jones, 1960. Writing, 1966, More & Sonawane, 1987). For determining calionic composition of Na*, K*, Ca++, mg*+ the haemolymph from control and starved grubs was obtained spectrophotometric analysis of cations were made as per (Hyatt and fylarshall, 1977) and the concentration of cations was determined by using Perkin-Elmer automic absorption spectrophotometer.

RESULTS AND DISCUSSION : Third tnstar grubs exposed to starvation for 45 days can survive upto 3 months with 5% mortality In the last stage of experiment (personal observation). The observation of the effect of starvation for 45 days on the body Vi^eight loss, total reducing sugars, glucose, proteins, lipids, total haemocyte dbunt (THC) and cationic composition are given in table 1. The result indicate that when 3'''' instar grubs were starved for 45 days it causes loss in body weight upto 2 1 % . Starvation also cause reduction in biochemical moieties like body reducing sugars by • 26%, glucose by 49%, proteins by 24% and lipids by 83%. The lolal haemocyte count (THC) in the starved grubs was considerably increased from 1850. mm^ of haemolymph to 3850/ mm^ of haemolymph. The cationic composition of haemolymph also gel affected due to starvation. The Na* get increased by 13%. The composition of cations like K*, Ca** and Mg** get decreased by 26%, 22% and 14% respectively during starvation. The haemolymph total sugar, glucose and protein in starved grubs also reduced by 79%, 100% and 63% respectively. Genera) observafion due to starvation on the physical appearance and anatomy of grubs during the course of starvation includes slight collapsed alimentary canal, malpighian (ubules filled with white granules of uric acid. Similar type of weight loss upto 48% due to starvation for 12 days in Manduca sexta larvae was reported by (Dahlman 1973a). In the present study there was a loss in body weight upto 21 % for 45 days. The biochemical moieties like total body reducing sugars and glucose get reduced by 26% and 49% respectively due to 45 days starvation of the grubs. Similar results were reported by earlier workers due to starvation in Locusta migratoria (Goldsworthy, 1969; Justum et.si, 1975. Mwangi and Goldsworthy, 1977; • Lim and Lee, 1981). The deprivation of food has been shown to elevate the level of total haemolymph lipid due to 5 day starvation Indicating decrease in the level of total body lipids (Justum et.ai. 1975; Mwangi and Goldsworthy, 1977; Hill and Goldsworthy, 1970; Lim and Lee, 1981). In 3'" instar grubs of Leucopholis /epidophora there is drastic loss in body lipids by 83%. It has also been suggested by Hill and Goldsworthy, (1970) that during starvation fat body glycogen is utilized before fat body lipid as an energy source in the 5'^ Instar larvae of Locusta migratoria. During prolonged period of starvation the ultimate source of energy substrate is tissue proteins in the final phase due to which there is a considerable reduction of total body proteins upto 24% in the 45 days starved grubs. Observation on, the similar line were also made by Lim and Lee;-{1981), in the grasshopper Oxyajaponica. They have reported 90% reduction of fat body proteins in 18 day old female starved for 4 days. Due to the exhaustion of most of metabolites from the haemolymph, (Table 1) during starvation the haemolymph In these grubs is less viscous and it also shows the overall decrease of cationic composition, (Table 1). Increase in Wood volume in welfed control Locusta was reported by Mwangi & Goldsworthy, (1977). This increase in blood volume can be accounted for the decrease in cationic composition. Similar conditions probably existed in the starved grubs of Leucophlis lepidophora in the present study because the blood volume is not determined or the exogenous cations obtained by the insect are stopped due to starvation. In the present study increase of total haemocyte count (THC) from 1 SSO/mm^ of haemolymph to 3850/mm^ of haemolymph was observed due to starvation. Similar observations were made by Jones decrease in total haemocyte count due to starvation in the larvae of Bombyxmon. The haemolymph total sugar, glucose and protein in starved grubs also get reduced by 79%, 100% and 63% respectively. Thus the prolonged starvation of the present work suggest that when the fossorial grubs were forced to starvation, show overall adverse effect on the tissue and haemolymph metabolites, haemolymph cationic decrease and total haemocyte

count (THC) increase. However, there is not direct evidence on the basis of which suggestion can be made about the ulilizalion ot these melabolities in the generation of energy.

ACKNOWLEDGEMENT : Author's are thanl^ful to the Prof, and Head, Department of'Zoology, Shivaji University, Kolhapur, for providing facilities.

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Arvy, L. Ivl., Gabe M. & J. Lhoste., Bull. Biol. Fr. Belg. 82 (1948) 37-60

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Barnes. H. & Biackstocl