Effect of elevated carbon dioxide on biology and morphometric parameters of yellow stem borer, Scirpophaga incertulas infesting rice (Oryza sativa)

An experiment was conducted at Research Farm, National Rice Research Institute, Cuttack, Odisha, India to quantify the effect of elevated carbon dioxide (CO2) concentrations on the biology and morphometric parameters of yellow stem borer (Scirpophaga incertulas, Pyralidae, Lepidoptera). Yellow stem borer is one of the major pest of rice in the whole rice growing regions of South East Asia. The effect of three carbon dioxide concentrations i.e. 410 ppm (ambient), 550 ppm and 700 ppm on the duration of the developmental period as well as morphometric parameters of each stage of the lifecycle of the pest was analysed. It was found that, there was an increase in the duration of the developmental period of each stage of life cycle as the concentration of CO2 increases. However, the life span of the adult moth was significantly lower under the elevated CO2 concentrations when compared with ambient CO2 concentration. Morphometric parameters viz., mean length, width and weight of each larval instar, pupa and adult were found to be significantly higher in elevated concentrations of CO2 as compared to ambient concentration.

Resistance of rice accessions against rice yellow stem borer, Scirpophaga incertulas (Walker) under greenhouse and field conditions

Sixteen rice accessions were screened under greenhouse condition and field condition against yellow stem borer (YSB) during 2014-15. Six wild accessions were screened against YSB under green house condition only. In green house condition, the accessions viz., Oryza minuta, O. nivara, IR 20, IET 23710 and IET 23715 recorded the score of 3 (moderately resistant) at both phases. Under field condition, the variety TKM 6 recorded score 1 (resistant) based on dead heart and white ear damage followed by IR 20, IET 23710 and IET 23715, which recorded the score of 3 (moderately resistant) for both dead heart and white ear damage. Both under field and green house condition, IR 20, IET 23710 and IET 23715 showed moderate resistance to yellow stem borer.

The Draft Genome of Yellow Stem Borer, an Agriculturally Important Pest, Provides Molecular Insights into Its Biology, Development and Specificity Towards Rice for Infestation

Yellow stem borer (YSB), Scirpophaga incertulas (Walker) (Lepidoptera: Crambidae), a major monophagous insect pest of rice, causes significant yield losses. The rice–YSB interaction is very dynamic, making it difficult for management. The development of resistant lines has been unsuccessful as there are no effective resistant sources in the germplasm. Genome information is necessary for a better understanding of interaction with rice in terms of its recognition, response, and infestation mechanism. The draft genome of YSB is predicted to have 46,057 genes with an estimated size of 308 Mb, being correlated with the flow cytometry analysis. The existence of complex metabolic mechanisms and genes related to specific behavior was identified, being conditioned by a higher level of regulation. We deciphered the possible visual, olfactory, and gustatory mechanisms responsible for its evolution as a monophagous pest. Comparative genomic analysis revealed that YSB is unique in the way it has evolved. The obvious presence of high-immunity-related genes, well-developed RNAi machinery, and diverse effectors provides a means for developing genomic tools for its management. The identified 21,696 SSR markers can be utilized for diversity analysis of populations across the rice-growing regions. We present the first draft genome of YSB. The information emanated paves a way for biologists to design novel pest management strategies as well as for the industry to design new classes of safer and specific insecticide molecules.

Komposisi Spesies Penggerek Batang Padi dan Parasitoid Telurnya pada Ketinggian Tempat yang Berbeda

Composition of Rice Stem Borer Species and Their Egg Parasitoids at Different Altitudes. Rice stem borer is one of the main pest of rice plants that always percolating and attack plants in the field. The pests can result in damage to plants and lost of the grain from season to season. The aim of this research is to know composition and dominance rice stem borer species and role of their eggs parasitoid at an altitude of different places. Research is done by survey based on the height of different altitude in rice plants two weeks after cropping up until eleven weeks after planting. Research conducted from April until August 2019 in rice field that belonging to farmers at Subak Cemagi Let, Cemagi Village and Subak Teba, Mengwi village, Badung regency, Bali province. Subak Cemagi Let are at an altitude of 15 meters above sea level whereas Subak Teba are at an altitude of 300 meters above sea level. Identification of Rice stem borer larvae and their eggs parasitoid done in Pest Laboratory, Agriculture Faculty of Udayana University. Found three species rice stem borer in the height 15 mdpl namely Scirpophaga incertulas; Sesamia inferens dan Chilo suppressalis, whereas in the height 300 mdpl found four species namely Scirpophaga incertulas, Sesamia inferens, Chilo suppressalis, dan Chilo polychrysus. S. incertulas was the most dominant at the two different altitude. Three species of eggs parasitoid that have role to suppress the development of rice stem borer at the different altitude namely Tetrastichus schoenobii, Telenomus rowani dan Trichogramma japonicum. T. schoenobii was the most dominant to suppress rice stem borer populations.

Diversity Of Insect Pests In Rice Plant (Oryza Sativa L) in The Rice Fields Of South Kualuh District, North Labuhanbatu

Eradicating rice pests in South Kualuh is difficult to do optimally, because most farmers do not understand the types of pests that attack their rice plants. The objective of this study was to obtain information about the type of pest insects in rice plants and to find out the diversity index of insect pests in rice plants. This research was conducted using trap method and collection of insects was done using a insect net. Observation data was analised using Shanon Wiener (H) diversity / diversity index. The result showed 13 types of pest insects which belongs to 10 families. That is Tettigonia sp.(Linnaeus, 1758), Sogatella furcifera (Horváth, 1899), Nephotettix virescens (Distant, 1908), Cofana spectra (Distant, 1908), Atractomorpha crenulata (Fabricius, 1793), Erotides sp.(Laporte, 1836), Leptocorisa acuta (Thunberg, 1783), Aulacophora indica (Gmelin, 1790), Chrysochus cobaltinus (LeConte, 1857), Silba capsicarum (McAlpine, 1956), Hercostomus germanus (Wiedemann, 1817), Cnaphalocrosis medinalis (Guenée, 1854), Scirpophaga incertulas (Walker, 1863). The diversity index of rice pest insects was categorized as moderate with a value of 2,35 and a dominance index of 0,108. This value indicates that the distribution of species is evenly distributed so that no insect species dominates in the area.