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Although CRISPR/Cas9 has been widely used in insect gene editing, the need for the microinjection of preblastoderm embryos can preclude the technique being used in insect species with eggs that are small, have hard shells, and/or are difficult to collect and maintain outside of their normal environment. Such is the case with Sogatella furcifera, the white‐backed planthopper (WBPH), a significant pest of Oryza sativa (rice) that oviposits inside rice stems. Egg extraction from the stem runs the risk of mechanical damage and hatching is heavily influenced by the micro‐environment of the rice stem. To bypass these issues, we targeted embryos prior to oviposition via direct parental (DIPA)‐CRISPR, in which Cas9 and single‐guide RNAs (sgRNAs) for the WBPH eye pigment gene tryptophan 2,3‐dioxygenase were injected into the hemocoel of adult females. Females at varying numbers of days posteclosion were evaluated to determine at what stage their oocyte might be most capable of taking up the gene‐editing components. An evaluation of the offspring indicated that the highest G0 gene‐edited efficacy (56.7%) occurred in females injected 2 d posteclosion, and that those mutations were heritably transmitted to the G1 generation. This study demonstrates the potential utility of DIPA‐CRISPR for future gene‐editing studies in non‐model insect species and can facilitate the development of novel pest management applications. [ABSTRACT FROM AUTHOR]

Plants are threatened by a wide variety of herbivorous insect assaults, and display a variety of inherent and induced defenses that shield them against herbivore attacks. Looking at the massive damage caused by the white-backed planthopper (WBPH), Sogatella furcifera, we undertook a study to identify and functionally annotate OsWRKY and OsNAC transcription factors (TFs) in rice, especially their involvement in WBPH stress. OsWRKY and OsNAC TFs are involved in various developmental processes and responses to biotic and abiotic stresses. However, no comprehensive reports are available on the specific phycological functions of most of the OsWRKY and OsNAC genes in rice during WBPH infestation. The current study aimed to comprehensively explore the OsWRKY and OsNAC genes by analyzing their phylogenetic relationships, subcellular localizations, exon–intron arrangements, conserved motif identities, chromosomal allocations, interaction networks and differential gene expressions during stress conditions. Comparative phylogenetic trees of 101 OsWRKY with 72 AtWRKY genes, and 121 OsNAC with 110 AtNAC genes were constructed to study relationships among these TFs across species. Phylogenetic relationships classified OsWRKY and OsNAC into eight and nine clades, respectively. Most TFs in the same clade had similar genomic features that represented similar functions, and had a high degree of co-expression. Some OsWRKYs (Os09g0417800 (OsWRKY62), Os11g0117600 (OsWRKY50), Os11g0117400 (OsWRKY104) and OsNACs (Os05g0442700, Os12g0630800, Os01g0862800 and Os12g0156100)) showed significantly higher expressions under WBPH infestation, based on transcriptome datasets. This study provides valuable information and clues about predicting the potential roles of OsWRKYs and OsNACs in rice, by combining their genome-wide characterization, expression profiling, protein–protein interactions and gene expressions under WBPH stress. These findings may require additional investigation to understand their metabolic and expression processes, and to develop rice cultivars that are resistant to WBPH. [ABSTRACT FROM AUTHOR]

Whitebacked Planthopper is a sucking phloem sap insect which can greatly affect quality of the grain and yield losses. Determination of the resistance and susceptibility to WBPH is very important to accurate QTL analysis. The main objective of the study was to examine the level of resistance to determine optimum screening time using 120 doubled haploid lines. CNDH populations were developed from anther culture of F1, which was derived after a crossing WBPH, Sogatella furcifera resistance 'Cheongcheong' and susceptible 'Nagdong' lines. The genetic map with average 9.6 CM between markers was constructed from 120 CNDH populations, which included 217 SSR markers. Four QTLs were detected at different time and points based on the rate of seedling mortality after WBPH infestation. The markers were found to be comprehensive in identification of genotype and phenotype at coincident rate of 95% 14 days after infestation. These markers are efficiently very useful for MAS and develop new varieties in rice breeding program. [ABSTRACT FROM AUTHOR]

During rice cultivation, brown planthopper (BPH, Nilaparvata lugens Stal.) and white-backed planthopper (WBPH, Sogatella furcifera) infestations cause decreased yield and rice quality. In this study, we attempted to develop multi-resistance plants and increase the marker-assisted selection (MAS) efficiency. The frequency of callus induction in 95 F doubled haploid lines (DHLs) derived from JSNDH13 (BPH resistance)/CNDH32 (WBPH resistance) ranged from 3.8 to 15.2 %. The plant regeneration rates varied from 2.9 to 39.3 %. Selected 75 DH plants were used to compare the results of WBPH bioassay and DNA marker reaction. The DHL bioassay showed continuous gene distribution and resistance score ranged from 0.5 to 9.0 (mean, 4.2). The broad-sense heritability for WBPH resistance was 51.7 %. The DHLs from the cross of JSNDH13/CNDH32 were segregated into 39 resistant (R):36 susceptible (S) to WBPH, i.e., 1 RR:SS. For the bioassay and MAS, RM11669 with WBPH resistance was selected. Genetically, the use of resistant cultivars, MAS, and DH breeding has proven to be environment friendly, efficient, and economical. This study confirmed the genetic basis for MAS to improve WBPH resistance in DHLs of WBPH/BPH resistant rice plants. [ABSTRACT FROM AUTHOR]

All ecofriendly alternative to chemical pesticides is biopesticides, which encompasses a broad array of microbial pesticides, biochemicals derived from micro-organisms and other natural sources, and processes involving the genetic incorporation of DNA into agricultural commodities that confer protection against pest damage. The field studies were carried out for effectiveness of insecticides and biopesticides against White backed Plant Hopper on rice in rewa region. Study of insect pest complex was done from 2006-07 to 2007- 08. The observations were made regarding the grain yield monocrotophos was the most efficient insecticide where as among biopescides wanis was the best. [ABSTRACT FROM AUTHOR]