Studies on white grub infesting different crop ecosystems and their management in sugarcane and soybean crops
Loading...
Date
2022-09
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
G.B. Pant University of Agriculture and Technology, Pantnagar, District Udham Singh Nagar, Uttarakhand. PIN - 263145
Abstract
The present investigation, entitled “Studies on white grub infesting different crop ecosystems and their management in sugarcane and soybean crops” was carried out during 2019- 20 and 2020 -21 at N.E. Borlaug Crop Research Center at G. B. Pant University of Agriculture and Technology, Pantnagar (U. S. Nagar), Krishi Vigyan Kendra, Majhera (Nainital) and Dharampur (Bareilly). The survey was conducted in various locations in the months of August, October and December in Uttarakhand and Uttar Pradesh to assess the infestation of white grubs in different crop ecosystems. Three horticulture crops (guava, mango, litchi) and two field crops were selected for the study. Result revealed that there was highest population density/m2 was recorded in sugarcane, followed by litchi and the least population was recorded from chilli fields during 2019 and 2020. Monitoring host preference of Holotrichia nagpurensis (Khan and Ghai) on various hosts like neem (Azadirachta indica), guava (Psidium guajava), jackfruit (Artocarpus heterophyllus), mango (Mangifera indica), Ficus microcarpa nitida, Ficus nitida variegata, Ficus benjamina, jamun (Syzygium cumini) and bakane (Melia azedarach) revealed that maximum number of beetles was recorded Ficus microcarpa nitida, followed by Neem, Ficus nitida variegata, jackfruit and jamun, while least number of beetle were recorded from mango, guava, bakane and Ficus benjamina. Multiple comparisons of feeding preferences among all hosts revealed that Ficus microcarpa nitida is the most significant preferred host plant for H. nagpurensis (Khan and Ghai) during the two consecutive year of study. The biology of H. nagpurensis was studied in vitro which showed the average life cycle completed in 276.82 days. The egg, grub and pupal period lasted for 14.25, 190.38 and 29.75 days, respectively, during 2020-21. On the basis of data collected from different light traps facilitated with different type of light source bulb revealed that significantly highest number of white grub was recorded in black light trap (7801 and 5038), followed by mercury light trap (5302 and 3832), LED white light trap (2298 and 1643) and LED blue light trap (963 and 785), while the lowest number of white grub beetles was recorded in incandescent light trap (587 and 523) during 2019 and 2020, respectively. Regarding the variation in white grub species, black light trap and mercury light trap had maximum number of
species variation i.e. 24 species was recorded followed by the LED white light trap (21 species), incandescent light trap (13 species) and the LED blue light trap with 9 species. Study revealed that black light trap is the most effective for white grub collection as a component of pest management. Evaluation of various insecticides for the management of white grub in sugarcane and soybean revealed that all the treatments were found to be significantly superior over control. Fipronil 40% + Imidacloprid 40% WG applied @ 300g a.i./ha was the most effective treatments followed by the Clothianidin 50WDG applied @ 120g a.i./ha in reducing the plant damage due to white grubs. The plot treated with Emamectin benzoate 5 SG applied @ 12.5 g a.i./ha was found least effective treatment, but significantly superior over control in reducing the plant damage due to white grubs during 2019 and 2020.