~ 1742 ~ Journal of Pharmacognosy and Phytochemistry 2020; 9(1): 1742-1745 E-ISSN: 2278-4136 P-ISSN: 2349-8234 JPP 2020; 9(1): 1742-1745 Received: 08-11-2019 Accepted: 12-12-2019 Ajita Soren Ph.D., Research Scholar, Department of Entomology, Birsa Agricultural University, Kanke Ranchi, Jharkhand, India MK Chakravarty Senior Scientist Cum Associate Professor, Department of Entomology, Birsa Agricultural University, Kanke Ranchi, Jharkhand, India PK Singh Chief Scientist Cum University Professor and Chairman, Department of Entomology, Birsa Agricultural University, Kanke Ranchi, Jharkhand, India Binay Kumar Junior Scientist cum Assistant Professor, Department of Entomology Birsa Agricultural University, Kanke Ranchi, Jharkhand, India Alka Kumari Ph.D., Research Scholar, Department of Entomology, Birsa Agricultural University, Kanke Ranchi, Jharkhand, India Chitrangada Pandey M.Sc., Department of Entomology, Birsa Agricultural University, Kanke Ranchi, Jharkhand, India Sushila Tudu M.Sc., Department of Horticulture, Birsa Agricultural University, Kanke Ranchi, Jharkhand, India Corresponding Author: Alka Kumari Ph.D., Research Scholar, Department of Entomology, Birsa Agricultural University, Kanke Ranchi, Jharkhand, India Seasonal incidence of leafhopper ( Amrasca biguttula biguttula ) and its effect of abiotic factors on brinjal crop Ajita Soren, MK Chakravarty, PK Singh, Binay Kumar, Alka Kumari, Chitrangada Pandey and Sushila Tudu Abstract A field trial was conducted at the Commercial Horticulture Unit of Birsa Agricultural University, Kanke, and Ranchi during rabi season of 2016-2017 and 2017-2018, in order to monitor the incidence and abundance of leafhopper. The activity of leafhopper started soon after the transplanting. The serious activities were noticed from 34 th August 2016 to second January 2017. The highest leaf hopper number per leaf was found as (12.0/3 leaves) at maximum temperature and minimum temperature 24.6 O C and 4.8 o C, respectively. The correlation was found positive and highly significant (r= -0.666**) with maximum temperature (r= -0.666**) and (r = -0.536*) minimum temperature. The maximum relative humidity and minimum relative humidity was (r = 0.288) and (r = -0.096) respectively observed the positively non-significant and positively non-significant correlation with population of leafhopper. In the year 2017-18, the peak (11.6/ 3 leaves) activity of leafhoppers was recorded at 46 th SMW. The pest was active throughout the season with a fluctuation range of 0.0 to 11.6 aphid per three leaves. The abiotic factors together were able to explain up to the extent of 78-74 per cent population dynamics fluctuation in leafhopper. Keywords: Solanum melongena, seasonal incidence, leafhopper, abiotic factors Introduction Brinjal, (Solanum melongena L.) is an important vegetable crop can be grown throughout the year on a wide range of soil and climatic conditions. Not only is a high yielding vegetable, brinjal also a high remunerative crop. There are various names of this crop in different parts of the world, some of which are as follows eggplant, guinea squash, aubergine, baingan etc. It is native of Indian sub-continent, with India as the probable centre of origin (Gleddie et al., 1986) [5] . Due to its versatility in use in Indian food, brinjal is often described as the ‘King of vegetables’ (Choudhary and Gaur, 2009) [4] . Nayar et al. (1976) [9] listed 53 insects attacking on brinjal. According to Mote, 1981 [8] ; Tripathy, et al. (1997) [10] in brinjal Leucinodes orbonalis is considered as the most serious pest all over the world. Atwal, A.S. (1976) [1] reported the abundance of L. orbonalis during monsoon periods. L. orbonalis was observed throughout the year on the brinjal crops (Mehta et al., 1980) [6] . The experiment was conducted to study the incidence and abundance of leafhopper in brinjal. Materials and Methods This field experiment was conducted to study the response of different entries/genotypes of little millet against leafhopper and the crop was grown without application of insecticide either in soil or as seed treatment. This was done to allow the natural population of leafhopper on crop. The experiment was done in two successive years i.e. 2016-17 and 2017-18. 21 varieties of brinjal were taken for this experiment i.e. Pusa Kranti (OP), Round Green Katedar, KUR BR-112(op), Brinjal green Round, Green long(op), F1 Hybrid PK-133, Green long F1 Hybrid, F1 Kusuma, F1 Hybrid KBRH-PK, F1 Hybrid Rajkiran, Brinjal-Sinduri F1 Hybrid, F1 Pratima, F1 Hybrid KBRH-Blue Magic, Brinjal Green Long, F1 Hybrid Super Chhaya, Swarna Pratibha palandu, Hybrid JK 8031, Swarna Shyamali Palandu, F1 Hybrid utkal Hybrid F1 Mali-128 and F1 Hybrid Brinjal No. 704. Seeds were sown in plots of 5m×2m at the Commercial Horticulture Unit with 60cm row to row and 60cm plant to plant spacing. The experiment was laid out in randomized block design with three replications. Meteorological data on temperature, rainfall, no of rainy days, relative humidity, wind speed and sun shine hours were obtained weekly, in both the years, from the meteorological observatory maintained in the Department of Agricultural Physics and Climatology, Birsa Agricultural