Int.J.Curr.Microbiol.App.Sci (2017) 6(8): 3006-3015 International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 6 Number 8 (2017) pp. 3006-3015 Journal homepage: http://www.ijcmas.com Original Research Article https://doi.org/10.20546/ijcmas.2017.608.360 Population Dynamics of Pink Stem Borer on Maize Crop and its Correlation with Prevailing Abiotic Parameters Sonali Deole*, V.K. Dubey and D.K. Rana Department of Entomology, Indira Gandhi Krishi Vishwavidyalaya, Raipur, Chhattisgarh-492012, India *Corresponding author ABSTRACT Population dynamics studies of pink stem borer was carried out during spring seasons of the year 2013-14 and 2014-15 at the Research cum Instructional Farm, IGKV, Raipur (C.G.). Larval population increased gradually and reached to a peak K e yw or ds th of 13.81 and 18.56 larvae /plant in 56 days (12 SMW) and 49 days (11th SMW) Maize, Pink stem in spring season during 2013-14 and 2014-15, respectively. The maximum adult th borer, Population population was trapped during fourth week of March (13 SMW) and third week of March (12th SMW), when the mean maximum29.7 ºC and 36.4ºC and minimum Dynamics, Weather temperatures were16.4and 19.4ºC and with mean relative humidities of 67 and Parameters . 47.5 per cent during the years 2013-14 and 2014-15, respectively. The interactions Article Info between the larval population and weather parameters revealed non-significant correlation. The interactions between the adult population and weather parameters Accepted: during spring 2013 and 2014 revealed negative and significant and non-significant 23 June 2017 correlation with maximum temperature (r = - 0.6519 and - 0.4964), negative and Available Online: significant correlation with minimum temperature (r = - 0.682 and r = - 0.566) 10 August 2017 while the interactions with morning and evening relative humidity was positive as well as significant with morning relative humidity (r = 0.610 and 0.649) but non- significant with evening relative humidity, respectively. Introduction Maize (Zea mays L.) or corn is a grass of the pests of minor importance are now assuming family Poaceae grown primarily for its kernel. major status. The scenario with respect to Maize is composed of 71.5 per cent starch, insect pests of this crop has changed a lot in 1.9 per cent protein, 4.8 per cent fat and 1.4 the recent past owing to increased area under per cent ash (Rathore, 2001). In Chhattisgarh, single cross hybrids and monocropping maize occupies an area of 242.52 thousand ha practiced by the farmers using indiscriminate with an average productivity of 1935 kg/ha quantity of insecticides and chemical (Anonymous, 2015). fertilizers. Insects attack maize throughout the cropping cycle and during storage, resulting The replacement of traditional local cultivars in as little as 10% to complete loss with the commercial varieties and hybrids led (Bergvinson et al., 2002). During the winter to expansion of arthropod pest complex as season pink borer with more extensive 3006 Int.J.Curr.Microbiol.App.Sci (2017) 6(8): 3006-3015 coverage, may cause damage up to 78.9% to recorded through light trap. The collections the crop. It is a pertinent point to note that were made throughout the crop season. productivity of maize in peninsular India is Number of pink stem borer, weekly catches higher than the northern states, and that of was correlated with the abiotic factors. winter maize (3.22 t/ha) is higher than the Meteorological data were received from rainy season maize (1.74 t/ha). Thus, to Department of Agro meteorology, IGKV, stabilize the maize production effective Raipur and were utilized for correlations and control of pink borer is of immense regression studies viz. the cumulative and importance (Santosh et al., 2012). Changing individual effects of temperature and relative climatic scenario with modern cultivation humidity on population buildup of S. inferens. practices in rice crop made pink stem borer to The influence of abiotic factors on the achieve pest status in many rice growing occurrence of pink stem borer of maize was regions of India (Sampath et al., 2014). The statistically analyzed by subjecting the occurrence of pink stem borer in relation to number of insects per plant and weather data weather parameters provides information on to simple correlation and multilinear the initiation and extent of damage which is regression analysis (Gomez and Gomez, useful for the effective management and 1994). formulation of IPM strategies on maize. Results and Discussion Materials and Methods The initial occurrence of S. inferens during A plot size of 200 m2 with sugar - 75 popular spring season 2013-14 was observed during hybrid was raised and maintained without the first week of February (6th SMW) i.e., at insecticide application to study the occurrence 14 days after germination with a mean of major insect pests on maize in relation to population of 3.82 larvae/plant. The average abiotic factors viz., maximum temperature, maximum and minimum temperatures minimum temperature, relative humidity prevailing during the initial infestation were (morning and evening).The spring maize crop 28.8 0C and 11.4 0C, respectively. While, the was sown on 22-01-2013 and 23-01-2014 average morning and evening relative following standard agronomical practices. humidity were 84 and 31 per cent The incidence of pink stem borer were respectively. The pest population increased recorded soon after noticing the initial gradually and reached to a peak on 12th SMW infestation and continued up to the maturity of i.e., 56 days after germination with a mean the crop at weekly intervals throughout the population of 13.81 larvae /plant. The average growing season. maximum and minimum temperatures prevailed during this period were 36.4 0C and The occurrence of maize pink stem borer, S. 20.2 0C, respectively and the average morning inferens, was observed by destructive and evening relative humidity were 66 and 22 sampling of 25 randomly selected plants at per cent, respectively. Thereafter, the pest five different locations @ five plants at each population was more or less uniform up to location of plot. Then the stems were split 14th SMW i.e., tasseling stage of the crop with open to count the number of larvae of 11.81 larvae/ plant, when the average Sesamia inferens at seven days interval maximum and minimum temperatures ranged starting from seven days after germination till between 38.1 0C to 38.7 0C and 22.7 0C to harvest of the crop. The seasonal population 21.5 0C, respectively and the average morning fluctuations of maize pink stem borer moth and evening relative humidity were ranged 3007 Int.J.Curr.Microbiol.App.Sci (2017) 6(8): 3006-3015 between 62 to 58 and 17 to 28 per cent, minimum temperatures prevailed during this respectively. The pest population declined period were 33.3 0C and 19.5 0C, respectively gradually with the rise in maximum and and the average morning and evening relative minimum temperatures and reached to a humidity were 89 and 38 per cent, minimum (1.00 larvae per plant) by 19th respectively. Thereafter, the pest population SMW, when the average maximum and was more or less uniform up to fourteenth minimum temperatures were 43.6 0C and 27.2 standard week (14th SMW) i.e., tasseling stage 0C and the average morning and evening of the crop with 10.67 larvae/ plant, when the relative humidity were 48 and 17 per cent, average maximum and minimum respectively (Figs. 1 and 2). temperatures ranged between 38.4ºC and 39.5ºC and 22.2ºC and 22.0ºC, respectively The adult moth appeared for the first time in and the average morning and evening relative the light trap during 5th SMW (19 adults) humidity were ranged between 67 and 59 and when the mean maximum and minimum 24 and 17 per cent, respectively. temperatures (28.8 and 11.4ºC) and the average morning and evening relative The pest population declined gradually with humidity were 84 and 31 per cent, the rise in maximum and minimum respectively. Maximum traps (44 adults / temperatures and reached to a minimum 1.67 week) were observed during 11th SMW, larvae/ plant by 18th SMW, when the average when, average maximum and minimum maximum and minimum temperatures were temperature (29.7 ºC and 16.4 ºC) and the 40.1ºC to 25.6ºC and the average morning and average morning and, evening relative evening relative humidity were 53 and 23 per humidity were 87 and 47 per cent, cent, respectively. respectively. After 15th SMW, number of adults decreased gradually to 2 pink borer During 2014-15 the pink stem borer adults moths/ week in 18th SMW when the were recorded throughout during growing maximum and minimum temperature (43.1 season in the light trap. Maximum adults (39 and 27.6ºC) and the average morning and adults /week) were trapped during 12th SMW, evening relative humidity were 51 and 21 per when average maximum and minimum cent, respectively. temperatures (36.4 and 19.4 ºC) and average morning and evening relative humidity were Similarly, during the second year of study i.e. 74 and 21 per cent, respectively. After 14th 2014-15, the pink stem borer larvae presence SMW, number of adults decreased gradually on the maize crop was noted in the first week to 1 pink borer moth/week in 19th SMW, of February (6th SMW) i.e., at 14 days after when the maximum and minimum germination with a weekly mean population temperature (38.1 and 26.0ºC) and the of 4.16 larvae/ plant. The average maximum average morning and evening relative and minimum temperatures prevailed during humidities were 59 and 27 per cent, the initial infestation were 31.7 0C and 14.8 respectively.