J.Biol. Control, 8 (2), 85-93, 1994

Studies on the Fauna of Sugarcane Ecosystem in Southern Peninsular India

S. EASWARAMOORTHY, H. DAVID, N.K. KURUP and G. SANTHALAKSHMI Division of Crop Protection Sugarcane Breeding Institute, Coimbatore - 641 007

ABSTRACT

Surveys conducted in three states of southern peninsular India revealed the occurrence of 57 species of belonging to 13 families of Araneae in the sugarcane ecosystem. Of these, only two species viz., greenalliae BlackwaH (Lycosidae) and Cyrtophora cicatrosa Stoliczka (Araneidae) were abundant, while six species were less abundant and 49 species were rare in occurrence. The spiders were found to colonize the sugarcane crop 40·45 days after planting. The population of the H.greenalliae which com­ prised more than 70% of the total population increased with age of the crop upto 180 days. There was no significant variation in the population of H.greenalliae in sugarcane cropped field and adjacent fallow land. The orb­ weaver spider C.cicatrosa started colonizing the crop 100 days after planting of the crop and its population increased upto 240 days. Population of H.greenalliae and that of all the species had negative association with maxi· mum temperature and rainfall and positive association with relative humidity. A reverse trend was noticed in C.cicatrosa. Soil and foliar application of insecticides recommended for the suppression of shoot borer, Chilo infuscatel­ Ius Snellen in the early stage of the crop growth did not exert any significant influence on the colonization of spiders. Among the five insecticides tested as foliar sprays at six month old crop, quinalphos, monocrotophos and endosul­ fan significantly reduced the spider population.

KEY WORDS: Sugarcane ecosystem, spiders, Hippasa greenalliae, Cyrtophora cicatrosa In India, sugarcane, a long duration field tic ides on colonization and popUlation build up crop is infested by a number of insect pest of spiders. species at different phases of its growth (David and Nandagopal, 1986). However, the physical MATERIALS AND METHODS characteristics of the crop limit the use of in­ Surveys were conducted at fortnightly in­ secticides once the canopy has closed (Fewkes tervals during 1988-91 at Sugarcane Breeding and Greathead, 1978). Consequently, the insec­ Institute, Coimbatore, Tamil Nadu. Additional ticide pressure is less in sugarcane. In India surveys were made at Kannur (Kerala) during only 2-3 per cent of the total insecticide con­ October and December 1989 and at Nellore sumption is on sugarcane (David, 1981). As a (Andhra Pradesh) during October 1990. During result, a large number of predators the survey, the plant and soil surfaces were are active in the sugarcane ecosystem (Eas­ examined carefully for the presence of spiders. waramoorthy et aI., 1988). But no systematic In addition, the plant whorls were also ex­ study has been carried out on the spider fauna amined. Only the adult spiders wcre collected inhabiting sugarcane fields. In the present in plastic tubes (lOx 2.5 cm) while the nymphs study, attempts were madc to detcrmine the were let free as they were not suitable for iden­ species complcxity of spiders, their seasonal tification. During the survey. searches were abundance and influence of weather, and insec- madc for a Juration of 4 man hours each time. Apart from this. at Coimbatorc, pit rail traps X6 EASWARAMOORTHY et al.

Table I. List of species of spiders encountered in sugarcane fields Family Species Status Habitat HUNTING SPIDERS Cluhionidac Cheiranthilltn daneili Takader Rare under stones, trashes and C. hilllalaWlflsis Gravely Rare in crevices C. lwlhillllaensis Tikader Less abundant Lyc()sidac '" Hippasu sp. Rare on the ground with or II. age/enoides Simon Rare without small webs fl. greenalliae Blackwall Abundant fl. pis(lurillll Blackwall Less abundant Lyco.w indagatrix Walckenaer Rare L. mackcl1ziei Gravely Rare L. malwiJalcshwarcllsis Tikader Rare L. tiSla Tikader Rare Pardosa birmanica Si mon Less abundant P. mysorensis Tikader and Mukerji Rare R. sumatrana Thorell Rare Oxyopidac Oxyopes ratnae Tikadcr Rare leaf spindle and lamina O. shweta Tikader Rare O. scmandae Tikader Rare Pecutia viridana Simon Rare P. latikae Tikader Rare Salticidae Marpissa sp. Rare leaves and leaf sheaths M. bengaiensis Tikader Rare lu. caleuttaensis Tikader Rare M. decorata Tikader Rare M. kalapani Tikader Less abundant Mymarahne sp. Rare Phidippus sp. Rare Phidippus bengalensis Tikader Rare P. indieus Tikader Rare P. pateli Tikader Rare P. punjabensis Tikader Rare Plexippus pateli Audouin Rare P.paykullii Audouin Rare AMBUSHING SPIDERS Thomisi'dae Thornisus projeetus Tikader Rare leaf spindle WEB-BUILDING SPIDERS Araneidae Argiope aemula Walckenaer Rare In large webs * A.anasuja Thorell Rare interconnecting the Cyrtophora cicatrosa Stoliczka Abundant leaves of adjacent plants Gasterocantha germinata Fabricius in the row or sometimes Less hetween rows sbundunt Spiders in sugarcane ecosystem 87

Table 1. (Contd.) Family Species Status Habitat G. hasseltii Koch Rare Gea corbetti Tikader Rare Leucauge decorata Blackwall Rare * L. pondai Tikader Rare L. tessallata Thorell Rare * * Neoscona rumpfi Thorell Rare N. theis Walckenaer Rare Theridiidae * Argyrodes sp. Rare in webs on the upper * A. projeles Tikader Rare portion of the plants Theridion tikaderi Patel Rare MISCELLANEOUS GROUPS Eresidae Stegodyphus pacipicus Pocock Rare S. sarasinorum Karch Rare Heteropodidae Olios sp. Rare O. obesulsus Pocock Rare Lys somanidae * Lyssamanes sp. Rare L. andamanellsis Tikader Rare Pholcidae Crossopriza [yoni Blackwall Rare * Pholcus phalallgioides Fuesslin Rare Pisauridae Euprosthellopes ellioti Cambridge Rare Tetragnathidae Tetragnatha Jletcheri Gravely Rare * Additional species collected from Kannur (Kerala) ** Additional species collected from Nellore (Andhra Pradesh) containing ethylene glycol were set on the observation. The plants in the entire quadrat ridges in sugarcane fields at a distance of 20 area and the soil surface were examined metres and the ground dwelling spiders that thoroughly during each observation for record­ were trapped and killed were collected on alter­ ing the spider population. Following the same nate days. The spiders were preserved in 70 per procedure, the population of H.greenalliae, the cent ethyl alcohol. The specimens were iden­ dominant species, was estimated in sugarcane tified by Dr.B.H. Patel, Professor and Head, field and adjoining fallow land during Novem­ Department of Zoology, Sir P.P. Institute of ber 1990 to March 1991. The data on spider Science, Bhavanagar, Gujarat, India. population collected during 1989-90 and 1990- 91 crop seasons were correlated with weather For studying the seasonal abundance of parameters like maximum temperature, mini­ spiders, sugarcane (variety CoC 671) was cul­ mum temperature, forenoon relative humidity, tivated in an area of 0.4 ha during the main afternoon relative humidity and rainfall that cropping season. Normal agronomic practices prevailed during the previous fortnight. were followed and no insecticide was applied. The field was divided into quadrats consisting Two field experiments were conducted of 5 rows of 6 meter length of sugarcane. during 1989-90 and 1990-91 crop seasons to During. each observation, spider population study the influence of insecticides on the initial was sampled in 5 quadrats, four on the four colonization and population build up of sides of the field and one at the centre. The spiders. Seven insecticides commoly recom­ sampling uni ts were changed randomly for each mended for the control of shoot borer, Chilo 88 EASWARAMOORTHY et al.

20~------~------'

oN 15 ------o F 8 P oI E R 8

45 80 75 90 105 20 35 50 85 80 95 210 25 40 65 70 85 300 15 30 AGE OF THE CROP IN DAYS

H.gTeenalllae -t- C.clcatroBB --- Other epeclea -a- Total population

, I Fig.l. Estimated population of spiders ('000) in one hectare of sugarcane field during 1989-90 crop season

injuscatellus Snellen, the most important pest Hoechst, Bombay) 0.0014 per cent W~~ made of sugarcane in peninsular India, were tested. on 35th day of planting. Observations were The experiments were carried out (variety recorded on the population of spiders form 45th CoC 671) during the main cropping season in day of planting upto 90th day during 1989-90, randomised block design (RBD) with eight and upto 135th day during 1990-91. treatments and three replications. Each plot measured 20 x 6 metres with an inter row spac­ During 1990-91 crop season the influence ing of 9.0 ems. Aldrin (aldrex 30 EC, NOCIL, of five foliar insecticides commonly recom­ Bombay) 1 kg a.Uha, and Lindane (Lindag 20 mended for the control of sucking pests -like EC, Coromandel Jndag, Madras) 1 kg a.i./ha scale insects, mealy bugs, leaf hopper and were applied at planting as soil treatment. Soil whiteflies on the popUlation of spiders was application of Sevidol (Carbaryl: Lindane 4:4; studied. The experiment (variety CoC 671) Sevidol 8G Rhone- Poulenc Agrochemicals, was conducted in RBDwith six treatments and Bombay), Chlorpyriphos lOG (Coromandel three replications. The plot size was 20 x 6 Jndag, Madras) and cartap hydrochloride metres. Malathion _(Corothion 50 EC, (Padan 4G, Coromandel Jndag, Madras) all at Coromandel Indag, Madras), dimethoate 1 kg a.i./ha and foliar application of endosulfan (Rogor 30 EC, Rallis India, Bombay), Endosul­ fan (Thiodan 35 EC, Excel Industries, Bom­ (Thiodan 35 EC, ExcelIndustries, Bombay) ~.1 per cent and decamethrin (Decis 2.8 EC, bay), monocrotophos (Corophos 40 EC, Coromandel Jndag, Madras), and quinalphos Table 2. Correlations between spider population and weather parameters during 1989-90 and 1990-91

Spider Max. Temp. Min.-:Jernp. Forenoon R..H. Afternoon R.H. Rainfall species 1989- 90-91 1989- 90-91 1989- 1989- 1989- 90 90 90 90-91 90 90-91 90 90-91 H. gree.na- NS NS NS NS Wae -.470* -.715* -.219 -.702* .871 * .507* -.087 .653* -.280 .057 C. cica NS NS NS NS NS trosa .821 * -.368 .330 -.482* -.896* .128 .896* .411 .791 * .013 All NS NS NS species -.536* -.719* -.205 -.715* .646* .513* -.400 .657* -.553* .053 Spiders in sugarcane ecosystem 89

10

N 8 0 0 F 6 S P I 4 0 E R S 2

..I IJ II II II -r 0 I .. 45 60 75 90 105 20 35 50 65 80 95 210 25 40 55 70 85 300 15 30 AGE OF THE CROP IN DAYS

_ H·l1reenalllae _ C.c/catrosa {Mkl Other species _ Total population

Fig.2. Estimated population of spiders ('000) in one hectare of sugarcane field during 1990-91 crop season (Ekalux 25 EC, Sandoz, Bombay) all at 0.1 per of 32 species of hunting spiders belonging to cent were applied at 6th month age of the crop. . Clubionidae, Lycosidae. Oxyopidae and Sal­ Observations on the spider population were ticidae; one species of ambushing spider made before the application of insecticides and belonging to Thomisidae; 14 species of web­ 2,7 and 15 days following the application. building spiders belonging to Araneidae and Theridiidae and 10 other miscellaneous The data on spider population were species (Table l) indicating the dominance of analysed (using analysis of variance) in fac­ hunting spiders. In an earlier study made at / torial randomised block design (Panse and Suk­ Gujarat, India, it was observed that 66.7 per hatme, 1967). cent of the spider population in the sugarcane ecosystem were hunting spiders (Anon. 1987). RESUL TS AND DISCUSSION In Louisiana also, hunting spiders formed the Surveys conducted in southern peninsular major group (Negm et al., 1969). In wheat India during 1988-91 revealed the occurrence Table 3. Influence of insecticides on colonization and build up of spider population during 1989 No. of spiders observed on day Insecticides 45 60 75 90 Mean Aldrin (30 EC) 1 kg aj.lha 1.0 2.0 2.3 4.3 2.4 Sevidol (8G) 1 kg aj.lha 1.7 1.0 2.7 4.3 2.4 Lindane (20 Ee) 1 kg a.i./ha 0.7 i.3 0.7 1.3 1.3 Endosulfan (35 Ee) 0.1% 1.0 1.3• 0.7 2.0 1.7 Chlorpyripho s (lOG) 1 kg a.i.lha 0.3 1.0 1.7 1.3 1.1 Padan (4G) 1 kg a. i.lha 2.7 1.7 0.7 2;7 1.9 Decamethrin (2.8 EC) 0.0014% 1.7 0.0 1.3 1.7 1.2 Untreated check 3.0 0.7 0.7 0.7 1.3 Mean 1.5 1.1 1.3 2.3 Between treatments N.S. Between periods C.D. = 0.8 (P=0.05) Treatment x peri od N.S. 90 EASWARAMOORTHY et af.

10 H i I G 8 R ~-.----.--- E I E I N 6 A L L 4 I A E 2

o NOV II DEC I DEC" JAN I JAN II FEB I FEB II MARl MONTH AND FORTNIGHT

_ SUGARCANE FIELD .. FALLOW LAND

Fig.3. Estimated population of H.greenalliae in ('000) in one hectare of sugarcane cultivated and fallow land fields in Canada, Iycosids were predominant the total collection and 39.4 per cent of the both in the field and field borders (Donae and hunting group of spiders (Anon., 1987). The Dondale, 1979). The surveys further revealed lycosid H.greenalliae accounted for more than that only two species, H. greenalliae 70 per cent of the collection at Coimbatore, (Lycosidae) and C. cicatrosa (Araneidae) were whereas in Gujarat, this species was not found abundant in sugarcane fields at Coimbatore. indicating wide variation in the species com­ Six species, two of Lycosidae, one each of plexity and diversity between agroclimatic Glubionidae, Oxyopidae, Salticidae and regions. The habitats of sugarcane field-dwell­ Araneidae occurred in less numbers. The ing spiders varied widely. The species of remaining 49 species were rarely encountered Clubionidae were generally found inside the in the sugarcane fields. The lycosids were leaf sheaths and leaf whorls. Different abundant and accounted for more than 70 per species of web-spinners constructed their cent of the spider population at Coimbatore. In web at different heights of the cane plant Gujarat, lycosids formed only 26.3 per cent of (Table1 ). Table 4. Influence of insecticides on colonization and build up of spider popUlation during 1990. No. of spiders observed on day Insecticides 75 90 105 120 135 Mean Aldrin (30 EC) r kg a.i.lha 0.7 1.0 9.7 8.0 8.3 5.5 Sevidol (8G) I kg a.i.lha 0.3 2.0 3.7 7.0 6.7 3.9 Lindane (20 EC) 1 kg a.i.lha 0.0 0.3 4.3 6.7 8.0 3.9 Endosulfan (35 EC) 0.1 % 0.0 1.3 4.3 7.7 7.3 4.1 Chlorpyriphos (lOG) 1 kg a.i.lha 0.0 0.3 3.0 9.0 7.7 4.0 Padan (4G) I kg a.i.lha 0.0 0.3 5.3 10.7 10.3 5.3 Oecamethrin (2.8 EC) 0.0014% 0.3 0.3 2.3 7.3 ] 0.7 4.2 Untreatli:d check 0.7 2.3 4.3 5.0 4.7 3.4 -.----~--~-----"----- Mean 0.3 l.0 4.6 7.7 g.O -~----- ~- -- ~- -~ ------~----- Between treatments: N.S. Between periods C.O. = 1.9 (P=O.05) Treatment x period N.S. Spiders in sugarcane ecosystem 91

Table 5. Influence of foliar application of insecticides on spider population

Pre- Per cent reduction I increase (+) in spider treatment population on day Insecticides spider Mean population 2 7 15 Malathion (50 EC) 0.1 % 40 40.0 25.0 2.5 22.5 Dimethoate (30 BC) 0.1 % 48 27.0 22.9 4.2 18.0 Endosulfan (35 Ee) 0.1% 47 44.7 34.0 23.4 34.0 Monocrotophos (40 EC) 0.1 % 41 80.5 70.7 53.7 68.2 Quinalphos (25 EC) 0.1 % 64 54.8 61.3 53.1 56.4 Untreated check 44 2.3 13.6 (+)25.0 (+)3.0 Mean 47.3 41.6 37.9 18.6 Between treatments C.D. = 3.6 (P = 0.05) Between periods C.D. = 3.3 (p=0.05) Treatment x period N.S. It was further confirmed that the wolf Interestingly, the population of H.greenal­ spider, H.greenalliae was the single dominant liae observed in a 9-12 month's old sugarcane species (Fig. 1 and 2). It accounted for an field and an adjoining land left fallow for one average of 70.5 per cent (range 25.0-98.9) of year did not differ significantly (Fig.3). spider population encountered during 1989-90 Similarly, the population of C.cicatrosa in the and 96.1 per cent (range 50.0 - 100.0) during sugarcane cropped area and fences in the field 1990-91. The orb-weaver spider, C. cicatrosa borders did not show much variation. Similar accounted for 29.0 and 1.6 per cent, while all results were obtained in rice fields and bund other species totalled only 0.5 and 2.3 per cent surveys. The most dominant species Lycosa of the population during the respective years. pseudoannulata Bosemberg colonized equally in rice fields and border areas(Nirmala, 1990). The spiders started colonizing the sugar­ According to Bardon and Litsinger (1981) cane fi~lds 40-45 days after planting when the grassy border areas harboured more spider sprouting of the crop was complete. Only hunt­ population than did the rice fields and field ing spiders and some miscellaneous groups bunds. were noticed upto 100 days of the crop. The web-building spiders started colonizing the The total spider population was found to be sugarcane fields after 100 days, when the negatively influenced by maximum tempera­ canopy became dense. The population of the ture, minimum temperature and rainfall. It spiders increased steadily upto 180 days and showed positive relationship with forenoon and thereafter it got fairly stablized. The population afternoon relative humidity (Table 2). The reached the peak of 19250 spiders per hectare trend was similar in the case of H. greenalliae. by 240 days during 1989-90 and 7920 spiders However, C. cicatrosa showed almost a reverse per hectare by 270 days during 1990-91 (Fig. 1 relationship. Its population was positi vely in­ & 2). Significantly less population of spiders fluenced by maximum temperature, afternoon especially the web- building ones observed relative humidity and rainfall. Many weather during 1990-91 may be attributed to the poor factors like temperature (Barnes and Barnes, crop growth. The initial cultural operations like 1954), relative humidity (Jones, 1941), sun­ field preparation, weeding, earthing-up, light (Pointing, 1965) and air-currents or winds manuring etc. may be the reasons for the delay (Cherrett, 1964) were known to influence the in the initial colonization of spiders in sugar­ spiders. Studies conducted in rice fields at cane fields from adjacent fallow lands and Coimbatore revealed that maximum tempera­ bunds. ture and afternoon relative humidity exhibited 92 EASWARAMOORTHYetat.

positive influence while forenoon relative nulata was poor even ten days after spraying. humidity and number of rainy days had nega­ Monocrotophos, another highly toxic chemical tive influence on the population of L. pseudo­ in the present study, was earlier found to be less annulata. However the population of toxic to Lycosa sp. (Chu et ai., ] 976 a,b). Tetragnatha javana Thorell in the same fields Oedothorax sp. (Chiu and Cheng, 1976) and L. was not influenced by weather conditions (Nir­ pseudoannulata (Salim and Heinrichs, 1985; mala, 1990). In the case of wolf spider H. Fabellar and Heinrichs, 1986). However, ac­ greenalliae which inhabits the soil surface, cording to Nirmala (1990) monocrotophos­ rainfall and subsequent flooding of the fields treated rice plots exhibited poor recolonization might have affected its population adversely, of L.pseudoannulata indicating high persist­ which may not be so in the case of orb-weaver ence of the insecticide. spider C. cicatrosa. However, the influence of The present survey conducted in southern weather factors on the population build up of peninsular India, revealed 57 species of sugar­ spiders needs further study. cane field-dwelling spiders. However, the The experiments conducted during 1989 ecosystem was dominated by H.greenalliae and 1990 revealed that soil and foliar applica­ throughout the crop growth period. According tion of insecticides in the early stages of crop to Cop pel and Mertins (1977), the hunting growth for the control of shoot borer C. infus­ spiders are aggressive and often remain in catellus did not adversely affect the coloniza­ specific habitats and if these coincide with the tion and population build up of spiders (Table habitat of a particular insect species, the results 3 and 4). During 1989 spiders started coloniz­ could be important in population suppression. ing the field by 45th day but during 1990 H. greenalliae inhabit around the basal portion colonization was noticed only in certain plots of the sugarcane shoot and this may have a by 75th day. As the insecticides were applied direct influence on the population of shoot well before the time by which the spiders borer C. infuscatellus in the early stage of the started colonizing the sugarcane fields, there crop growth as the young larvae are wind dis­ was no. significant influence of these insec­ persed and wander around the basal portion of ticides on colonization and build-up of spider the plants before settling at the first leaf sheath population. region. Cage experiments (Easwaramoorthy et a!., unpubl.) showed that the spiders could Foliar application of insecticides against reduce the infestation of the borer. In sucking pests at 180 days after planting af­ laboratory tests, the spiders fed readily on fected the spider population. The per cent various life stages of shoot borer and other reduction in the population was greatest on the sugarcane pests infesting the later stages of the second day after pesticide application. But by crop. However, the extent of control offered by 15th day, the spider started recolonizing the the spiders needs further study. plots as indicated by increase in the population. Monocrotophos and quinalphos were highly The dominant species, H. greenalliae is toxic to spiders. The per cent reduction in found to colonize the sugarcane field, fallow spider population was 80.5 and 54.8 on the land and field bunds equally. This may be second day in monocrotophos and quinalphos­ beneficial, as spiders harboured in fallow lands sprayed plots respectively (Table 5). Even on and bunds are not subjected to the toxic hazards the 15th day, the population reduction was 50 of pesticides and later they can invade and per cent indicating poor recolonization in these colonize the sugarcane fields. The population plots. In the rice ecosystem also, quinalphos build up of the spiders is not affected by the was considered to be highly toxic to spiders insecticides applied hefore their colonization. (Rajendran, J987; Nirmala, 1990) as the However, foliar application of insecticides recolonization of wolf spider L. pseucioan- after their colonization adversely affected the Spiders in sugarcane ecosystem 93 spider population. Recolonization is faster in DAVID, H. and NANDAGOPAL, V. 1986. Pests of plots applied with certain insecticides like sugarcane - Distribution, symptomatology of at­ tack and identification. In "Sugarcane Entomol­ dimethoate and malathion indicating the need ogy in India" (David, H., Easwaramoorthy, S. to screen pesticides for their selectivity to the and layanthi, R. eds.) Sugarcane Breeding In­ predators. stitute Pub!. Coimbatore, India. pp. 11-29. DOANE, J.F. and DONDALE, C.D. 1979. Seasonal ACKNOWLEDGEMENT captures of spiders (Araneae) in a wheat field and its grassy borders in Central The authors are thankful to Dr.K.Mohan Sanskatehewan. Can. Entomol., 111, 439-445. Naidu, Director, Sugarcane Breeding Institute, EASWARAMOORTHY, S., KURUP, N.K. and Coimba'tore, for providing all the necessary SANTHALAKSHMI, G. 1988. Arthropod facilities and to Dr.B.H. Patel, Professor and predators in sugarcane pest management. In "Biocontrol Technology for Sugarcane Pest Head, Department of Zoology, Shri P.P. In­ Management" (David, H., and Easwaramoorthy, stitute of Science, Bhavnagar, Gujarat, for the S. eds.) 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