INTRODUCTION:

The sugarcane is a thick, tall, perennial grass which tillers, at the base, to produce a stem of 3-4m height. It is cultivated as store a high concentration of sucrose in the stem. The insect Pyrilla, has recently become an endemic pest and is posing a great problems in the sugar industry. Pyrilla perpusilla is major insect feed on the cell-sap, that extensively affects its production (Kumar and Yadav, 2006). The pest remains active during plantation to harvesting with 3-4 numbers of generations with optimum activity in rainy season and survives on several crops during winter (Shah and Saleem, 2002).

Pyrilla perpusilla is being attacked by several parasitoids in tropical climate. The predators as Tetratichus pyrillae (Crawford), Oenocyrtus spp. Lastrodrymus spp. and Metarhizium spp. regulating the pest population (Dhaliwal and Baina 1983; Verma and Singh 1987). Ecto-parasitoid Epiricania melanolenca (Lepidoptus, Epipyropidea) was existing in India as the effeive parasitoid of sugarcane leafhopper. This parasitoid with several species exploited to similar control in various weather conditions.

METHODS AND MATERIALS:

In the experiment, sixty sugarcane leaves were selected randomly to sugarcane leafhopper infestation. The infested Pyrilla showed white scars on dorsal parts and pleaural abdmonal region respectively. Then percentage parasitism by Epiricania melanoleuca was estimated with formula given by Mishkat and Khalid (2007) as –

No. of Parasitized nymphs and Adult

Percent parasitization (%) = –––––––––––––––––––––––––––––

Total No. of nymphs and adult x 100

RESULTS AND OBSERVATIONS:

Parasitization of P. Perpusilla by the Epriricania melanoleuca (Fletcher):

The parasitization of sugarcane leafhopper by Epiricania melanoleuca revealed that this parasitoid was active from September to January. Observation was performed on P. perpusilla in 60 sugarcane leaves during experimentation infestation. The ectoparasitoid was first appeared (0.23 cocoons/leaf) in last September when Pyrilla existed as 7.47 and 0.83 per leaf of sugarcane were observed. Parasitoid population gradually increased up to October as 16.60nymphs and 1.03 adults were noticed with 0mm rainfall, 32.40°C and 21.87°C temperatures, 84.50% relative humidity 0.94km/hour wind velocity and 8.61hours/day as photoperiod (Table 1).

Table 1. Nymphal and Adult parasitization by Epiricania melanoleuca (Fletcher) on Sugarcane leafhopper under field conditions during 2014-2015.

Time	Population of Pyrilla Perpusilla		*E. melanoleuca* Cocoon/Leaf Population	Percentage Parasitization
	Average Nymph/ Leaf	Average Adult/ Leaf	*E. melanoleuca* Cocoon/Leaf Population	Nymph of Pyrilla	Adult of Pyrilla
Sept 30	7.47	0.83	0.23	0.00	0.00
Oct 15	16.60	1.03	1.87	2.11	28.93
Oct 30	7.67	1.00	0.40	32.60	11.67
Nov 15	6.07	0.37	0.33	16.53	31.67
Nov 30	3.13	1.03	0.20	24.77	20.00
Dec 15	3.53	0.47	0.50	35.21	2.33
Dec 30	1.87	0.67	0.27	18.99	16.67
Jan 15	1.10	0.33	0.17	18.21	10.00

Thereafter the insect population gradually reaching 1.10 nymphs and 0.33 adults/leaf and parasitoid population as 0.17 cocoons/leaf during early January. The nymphs, adults and parasitoid population ranged from 1.10 to 16.60, 0.33 to .03 and 0.17 to 1.87 numbers/ leaf during last September to early January respectively. Parasitoid population entered in October. The nymphal parasitization of P. Perpusilla by parasitoid ranged from 2.11-35.21 percent and maximum 35.21% was noticed with 0mm rainfall, 30.43°C and 14.30°C temperatures, 69.07% relative humidity, 15.9km/h wind velocity and 8.15hours/day as photoperiod hours prevailed at early December respectively.

Figure 1: Nymphal and Adult parasitization by Epiricania melanoleuca on Sugarcane Leafhopper during study period.

However, the adult Pyrilla. parasitized by E. melanoleuca ranged from 2.33-31.67% with highest 31.67% prevailed in early November (Fig. 1). At the appearance of the E. melanoleuca no parasitization was observed on last September. The parasitization was first observed in early October with 31.04% increased as 48.2% in November and then gradually decreased in the early January with 28.21% respectively.

DISCUSSIONS:

It was experienced that parasitoid suppress the Pyrilla population as potential bio-control agent. The Ectoparasitoid E. melanoleuca was enters in last September and gradually increased in early spring season than goes fall down in December to January at Gopalganj region. Variation in parasitoid resulted perhaps due to spatial differences. Chaudhary, et al., (1990) reported that Epiricania melanoleuca suppressed parasite population. The heavy parasitism as 12.5 to 24.6% was noticed. Prasad et al (1988) concluded that parasitoid effectively suppressed the pyrilla population during July. Joshi and Sharma (1992) investigated the ectoparasitoid on sugarcane crop. The peak parasitism has observed in October as 47.9% which further decline in December.

Pawar, et al., (2002) reported effectiveness of parasitoid on P. perpusilla. The insect initially appeared in June-July. Mishkat and Khalid (2007) found that P. perpusilla population reached top during November whereas parasitoid peak during September and similar findings were found by Rajak (2007) who explained that E. melonoleuca successfully controls the parasite.

Kumar, et al., (2008) observed peak infestation on per leaf of pyrilla as 6.67, 22.67 and 18.00 on 30th July, 30th and 15th August respectively. The peak value of parasioid/leaf were 8.00, 27.33 and 18.67 on 30th September, 30th October and 15th November respectively. More similarly, Pandey, et al., (2008) recorded parasite and parasitoid population and reported insect colony as 89.50/ leaf in June due to maximum temperature low humidity and slow multiplication of parasitoid. The insect has limited in July due to adequate parasitoid in fields.

REFERENCES:

1. Chaudhary JP, Kaushik SK, Singh R and Mrig KK (1987): Role of natural enemies in the suppression of sugarcane leaf hopper Pyrilla perpusilla Walker. FAO Plant Protection Bulletin 35: 15-19.

2. Chhillar BS and Madan YP (1992): Biological Control of Sugarcane Leafhopper, Pyrilla Perpsilla Walker, Indian Sugar, 42(9): 691-694.

3. Dhaliwal ZS and Bains SS (1983): A laboratory technique for rearing sugarcane leaf hopper Pyrilla perpusilla (W alker). Uttar Pradesh Journal of Zoology 3: 164-165.

4. Pandey G, Pandey MN, Mishra VK, Singh S, Singh DN and Singh SB (2008): Studies on the Effect of Eco-friendly Bio-agent E. melanoleuca for the Control of Sugarcane Pyrilla in Eastern UP, Indian Agriculatural Research Article 23(2): 91-95.

5. Pawar, A.D. (1987): Biological control of sugarcane pests in India. Plant Protection Bulletin 39: 1-6.

6. Prasad J, R Singh and Pawar AD (1988): Augmentation of Epiricania melanoleuca for the Control of Pyrilla Perpusilla in Western UP, Plant Protection Bulletin, Ind. 40(1): 29-31.

7. Rana ZA, Mahmood MM and Hashmi AA (2002): Population Dynamics of Pyrilla and Its Parase E. melonoleuca Fletcher at Faislabad, Pakistan, Journal of Agricultural Research, 17(3): 267-272.

8. Varma A and Singh K (1987): Metarhizium anisophiae (Metschikoff) Sorokin in the Management of Pyrilla Perpusilla Walker, The Sugarcane Leafhopper, Entomologist News Letter (No. 18), pp. 12.

Received on 26.11.2020 Modified on 28.11.2020

Research J. Science and Tech. 2020; 12(4):299-301.

DOI: 10.5958/2349-2988.2020.00042.X