Gall Midge Resistance Research Articles

Molecular Confirmation for Gall Midge (Biotype 3) Resistance in Phenotypically Resistant Rice Genotypes Using Functional Markers

This study performed molecular screening of rice genotypes, which showed no gall infestation in field conditions at the Regional Agricultural Research Station (RARS), Jagtial, during rabi, 2021-22. using functional markers such as “gm3del3” for the gm3 gene, “LRR del” for the Gm4 gene, and “PRP” for the Gm8 gene, six genotypes were analyzed. WGL-1145 contained all three resistance genes (gm3, Gm4, and Gm8). Additionally, three genotypes namely WGL-1147, WGL-1127, and Kakai had the Gm4 and Gm8 genes, while RP-5332-54-11-8-2-13 had only Gm8 and IR72476-B-P-9-3-1-1 possessed only gm3. These findings contribute to developing new rice varieties with resistance to gall midge, which can improve crop yields and food security in affected regions. Some promising rice varieties may be used as donors in breeding programs aimed at creating pyramided lines with durable gall midge resistance.

Monitoring of Virulence of Gall Midge (Orseolia oryzae Wood-mason) Population on Rice

A study was conducted for two years during 2022 and 2023 at Regional Agricultural Research Station, Warangal, Telangana, India to know the virulence of gall midge on rice varieties with known gall midge resistant genes at Warangal. During both the years i.e., 2022 and 2023, the virulence of gall midge was low in Aganni followed by Akshayadhan, W1263 and Purple. The gall midge virulence was very low and similar in Aganni and Akshayadhan which reveals the efficacy of gall midge resistance genes i.e., Gm4 and Gm8 against gall midge biotype 4M at Warangal. Since Purple variety does not have any gall midge resistant genes, gall midge virulence was highest on Purple variety. The study revealed that, gall midge genes viz., Gm4 and Gm8 are holding good for resistance against gall midge biotype 4M in both the years of study. However, a close monitoring of the virulence pattern in endemic areas is important for deployment of effective genes in developing resistant varieties.

Genetic Validation of Promising Warangal Rice Cultures for Gall Midge Resistance Using Functional Markers

Genetic Validation of Promising Warangal Rice Cultures for Gall Midge Resistance Using Functional Markers

Genetic Enhancement of Blast and Bacterial Leaf Blight Resistance in Rice Variety CO 51 through Marker-Assisted Selection

The increased use of chemicals in rice farming poses significant issues regarding the emergence of pesticide/fungicide resistance and environmental sustainability concerns. This study was aimed at the genetic improvement of blast, bacterial leaf blight (BB) and gall midge resistance in a popular rice variety CO 51 which already harbours a blast resistance gene Pi54. Efforts were made to pyramid an additional blast resistance gene Pi9 along with two BB resistance genes (xa13 and Xa21) and two gall midge resistance genes (Gm1 and Gm4) into an elite rice variety CO 51 to enhance the resistance level to biotic stresses. The superior lines were selected using functional markers conferring resistance to blast (NBS4 and Pi54MAS linked to Pi9 and Pi54 genes, respectively) and BB [(xa13Prom (xa13) and pTA248 (Xa21)] and SSR markers linked to Gm1 (RM1328) and Gm4 (RM22550) for phenotypic screening and agronomic evaluation. The genotyping and phenotyping of F6 and BC2F6 progenies of CO 51 X 562-4, for agronomic traits and resistance to BB and blast, identified ten superior progenies in F6 and five superior progenies in BC2F6. The breeding lines harbouring both xa13+Xa21 exhibited high levels of resistance to BB (score ≤ 1 cm) and Pi9+Pi54 exhibited strong resistance to blast (score ≤ 2). Identified lines can be evaluated further for varietal improvement or utilised as genetic stocks in breeding programs.

Genetic Analysis of Quantitative Traits, Gall Midge and Brown Spot Tolerance in Rice (Oryza sativa L.) Genotypes under Irrigated Ecosystem

Gall midge and brown spot of rice are a fungal disease that affect both seedlings and mature plants. To investigate resistance of rice to this disease twenty nine rice cultures were evaluated under irrigated ecosystem at Regional Agricultural Research Station, Jagtial during kharif, 2020. High heritable estimates were observed for all the 8 traits studied. High estimates of heritability was recorded for important yield attributes viz., days to 50% flowering (91.4, 11.24), plant height (77.8, 9.53), 1000-grain weight (98.4, 54.5), number of grains per panicle (78.3, 40.18) and grain yield (98.7, 33.87) indicated that these traits were under the control of additive genes. Significantly positive correlations were recorded with plant height, Number of productive tillers per plant and 1000 seed weight at both genotypic and phenotypic levels, the results clearly indicated that long duration genotypes with more height and bolder grains contribute for more grain yield. Among the eight traits studied, 1000 grain weight contributed highest (67.8%) towards total divergence followed by days to 50% flowering (11.5%), number of grains per panicle (6.06) and Galls midge incidence percentage (6.06%). Genotypes, JGL 38957 of cluster II, JGL 38950 of cluster III, JGL 38935 of cluster IV and JGL 38921 of Cluster VII could be the best source to develop brown spot, gall midge resistance and high yielding rice varieties.

Marker‐trait association analysis for gall midge (Orseolia oryzae) resistance in a diverse rice population

AbstractDamage caused by insect herbivores, notably Asian rice gall midge, Orseolia oryzae is more prevalent in the rice‐growing belts of India's southern and north‐eastern states. As a prelude to resistant cultivar development, the identification of genomic regions for resistance in the source population is crucial. In the present investigation, 202 rice genotypes were phenotyped and assayed with genomic markers reported for gall midge resistance. Positive skewness and platykurtic distribution of response scores suggested the inheritance of gall midge resistance in the study population. The marker gm3del3 contributed the most genetic variation, followed by RM28574 and marker RM22709 explained minimal variation. A marker‐trait association analysis with a single marker‐trait linear regression approach was performed to discover gall midge resistant genomic region/genes. The marker RM17480 on chromosome 4 reported to be linked with gm3 gene was found significantly associated with the gall midge resistance genomic region with allelic effects in a negative direction favouring resistance reaction. The allelic effects of significantly associated markers were correlated significantly with the phenotypic variation of gall midge damage scores. Genes identified in the vicinity of this marker contribute to stress response reactions in rice plants. The 200 bp allele of the marker was associated with susceptibility, while the 250 bp allele was associated with resistance expression. This allelic association with trait variation suggests the importance of associated marker for utilisation in marker‐assisted selection programmes to incorporate resistance alleles into elite rice genotypes.

Identification of New Sources of Resistance to Rice Gall Midge Biotype 3 (GMB 3) Prevailing in Jagtial, Telangana, India

Aim: To screen different rice entries against rice gall midge, (Orseolia oryzae) biotype 3 under field conditions.
 Place and Duration of Study: A total of 84 rice germplasm lines along with resistant and susceptible checks were evaluated against rice the gall midge, (Orseolia oryzae) biotype 3. These studies were conducted during Kharif season (2021) under field conditions at the Regional Agricultural Research Station (RARS), Jagtial.
 Methodology: Data on the total number of plants and plants with silver shoots including the number of silver shoots per plant were also recorded on 30 and 50 days after transplantation. Gall midge incidence as silver shoot scored according to the standard evaluation system, International Rice Research Institute (IRRI) for gall midge [1].
 Results: Six entries viz., KAKAI, SINNA SIVAPPU, PTB-12, WGL-1145, WGL-1147 and WGL-1127 had shown high resistant (score 0) to gall midge. Four entries viz., IR72476-B-P-9-3-1-1, RP-5332-54-11-8-2-13, WGL-1143 and SUDD HONDARAWALA were found resistant (score 1) against gall midge.
 Conclusion: The entries KAKAI, SINNA SIVAPPU, PTB-12, WGL-1145, WGL-1147 and WGL-1127 exhibited the high resistance against gall midge. Hence, they can be developed as varieties or can be used in breeding programme as a source of gall midge resistance.

Genetic analysis and fine mapping of the gall midge resistance gene Gm5 in rice (Oryza sativa L.).

The rice gall midge resistance gene, Gm5, confers remarkable antibiosis and is located in the same region on chromosome 12 in three different rice varieties. Fine mapping narrowed this region to a 49-kb segment and identified two candidate genes showing remarkableresponse to GM infestation. The Asian rice gall midge (GM; Orseolia oryzae; Diptera: Cecidomyiidae) invades rice shoots and forms galls, adversely affecting plant growth and yield production. Thus, the development of resistant varieties through the identification, mapping, and application of GM resistance genes is considered the most efficient strategy for managing this insect. Here, a GM resistance survey of F2 populations derived from intercrosses between resistant rice varieties 'ARC5984,' '570011,' and 'ARC5833' indicated that the resistance gene Gm5 was located on the same chromosomal region in the three varieties. For the initial mapping, three independent F2 mapping populations were developed for the three resistant varieties, and the Gm5 gene was consistently mapped to the same chromosomal region near marker 12M22.6. Fine mapping, which was conducted using the BC1F2 and BC2F2 populations derived from the 9311/ARC5984 cross, narrowed the Gm5 gene region to a 49-kb segment flanked by the markers Z57 and Z64. In the final mapped region, we detected 10 candidate genes, of which six were analyzed for their relative expression. Consequently, two of these genes, Os12g36830 and Os12g36880, showed significantly higher expression in GM-resistant plants than in GM-susceptible plants at 24 and 72h after GM infestation. Finally, the PCR amplification of markers 12M22.5 and 12M22.6 yielded clear single bands, and these markers were effectively applied for the marker-assisted selection (MAS) of the Gm5 gene. With the developed MAS markers, the fine mapping of this resistance gene will facilitate its map-based cloning and incorporation into insect-resistant rice varieties through breeding.

Characterization and application of a gall midge resistance gene (Gm6) from Oryza sativa 'Kangwenqingzhan'.

The resistance gene Gm6 was mapped and characterized using near-isogenic and pyramided lines, followed by marker-assisted selection to develop lines with resistance to both gall midge and brown planthopper. The Asian rice gall midge (GM; Orseolia oryzae; Diptera: Cecidomyiidae) is a major destructive pest affecting rice cultivation regions. The characterization of GM-resistance genes and the breeding of resistant varieties are together considered the most efficient strategy for managing this insect. Here, the Gm6 resistance gene derived from the Kangwenqingzhan (KW) variety was found to be located on the long arm of chromosome 4 using the F2 population of 9311/KW. The region was narrowed to a 90-kb segment flanked by the markers YW91 and YW3-4 using backcrossing populations. Based on no-choice feeding and host choice tests, GM development and growth in near-isogenic lines (NILs) were severely restricted compared to that in the 9311 control. On day 8, the average GM body length was 0.69mm and 0.56mm on NILs and 9311, respectively, and the differences were more significant at later time points. However, GM insects exhibited no host preference between NILs and 9311, and there was normal egg hatching on the resistant plants. We developed pyramided lines carrying BPH27, BPH36, and Gm6 by crossing and backcrossing with marker-assisted selection. These lines were similar to the KW parent in terms of agronomic traits while also exhibiting high resistance to brown planthopper (BPH) and GM. The present mapping and characterization of Gm6 will facilitate map-based cloning of this important resistance gene and its application in the breeding of insect-resistant rice varieties.

Morphological and Biochemcal basis of Gall Midge Lasioptera bryoniae (Schiner) resistance in Bitter gourd

Twenty-two germplasms of Bitter gourd (Momordica charantia) was screened for their resistance against bitter gourd gall midge Lasioptera bryoniae. Total number of maggots/gall was correlated with length and width of the gall. Gall midge infestation indicated that IC 582449 was resistant with the gall index of 35.86 as compared to susceptible germplasm of IC 582411 with gall index of 437.22. The resistant and susceptible germplasms were subjected to biochemical analysis. Biochemical parameters viz., total phenol, total sugars, total protein, total amino acid, total chlorophyll; nucleic acids viz., Total DNA, Total RNA and peroxidase activity were analysed for both infested and uninfected plants. Results showed that gall index is the one of the reliable factors to confer the resistance in gall midge resistance. Whereas in biochemical parameters total phenols and total sugars are the resistance conferring factors against the gall midge in bitter gourd.

Map-based cloning and validation of a gall midge resistance gene, Gm8, encoding a proline-rich protein in the rice variety Aganni.

The Asian rice gall midge (ARGM), Orseolia oryzae is an important insect pest causing an annual yield loss of about US$ 80million in India. Till now 11 R genes and seven biotypes of the pest have been characterized and reported. The indica rice variety Aganni, a landrace from the state of Kerala, is known to carry the gall midge resistance gene Gm8 with HR-type of resistance. This gene has been fine mapped within 0.43Mb region with the flanking markers RM22685 and RM22709. We identified 63 possible candidate genes through in silico analysis in the reference Nipponbare rice genome between 7.5 and 9.5Mb region. One of the markers targeting the proline rich protein (PRP) gene (LOC_Os08g15080) showed polymorphism between the parents and also exhibited complete co-segregation with the trait in 426 F10 RIL populations. Functional validation of this gene through RT-PCR in contrasting parents and Pre-NILs (near isogenic lines) revealed that this is an early responsive gene with rapid induction at 24h after gall midge infestation (hai) followed by subsequent reduction in the expression levels at late hours. Validation of this gene in five gall midge resistant rice varieties carrying different resistance genes revealed that the induction was unique to Aganni rice carrying Gm8 gene. Further, cloning and sequencing of the alleles of this gene including promoter region from TN1 (susceptible parent) and Aganni (resistant parent) revealed 153 nucleotide substitution, four amino acid substitutions and three mutations at putative cis-acting elements in TN1 when compared to Aganni. In addition, we also developed a functional marker (PRP-del) for detection of the gene for use in marker-assisted introgression of Gm8.

English

English

Expression Profiles of Key Genes Involved in Rice Gall Midge Interactions Reveal Diversity in Resistance Pathways

Resistance against the Asian rice gall midge, Orseolia oryzae (Wood-Mason), is conferred by any one of the 11 major genes identified so far. Resistance conferred by these genes may or may not involve a hypersensitive reaction (HR). Three of these gall midge resistance genes have been already cloned. In this study, expression of 20 key genes, identified based on our earlier studies, in 12 rice genotypes was profiled through quantitative real time (RT)-PCR at two time points. Results highlighted diversity in resistance pathways either involving reactive oxygen species (ROS)-hypersensitive reaction (HR) salicylic acid-mediated systemic acquired resistance or strong suppression of ROS-HR at initial stage itself. Some of the susceptible test genotypes derived from crosses between gall midge resistant and susceptible parents expressed trace activity of these genes even during compatible interaction.

Marker-assisted selection for biotic stress (Bacterial leaf blight and gall midge) tolerance in Bc4F4 generation of rice (Oryza sativa L.)

Bacterial blight (BB) of rice caused by the pathogen Xanthomonas oryzae pv. oryzae and the insect gall midge (GM) (Orseolia oryzae) are two major limitations of rice production. The present study was carried out to improve CO 43 a popular variety of Tamil Nadu for BB and GM resistance through marker assisted backcross breeding. Two sets of genes Xa21 and xa13 for bacterial blight resistance and Gm1 and Gm4 for gall midge resistance were used for this study. A total of 95 plants in BC4F4 generation were genotyped with SSR markers RM1328, RM22550, xa13 prom and pTA248 for the genes Gm1, Gm4, xa13 and Xa21 respectively. Artificial screening for bacterial blight screening was conducted in glass house condition and gall midge screening was conducted in the field condition. The lines selected for bacterial blight and gall midge resistance genes recorded a high level of resistance than the recurrent parent CO43.

Evaluation of rice pre-breeding lines for gall midge resistance

Evaluation of rice pre-breeding lines for gall midge resistance

Marker-assisted pyramiding of bacterial blight and gall midge resistance genes into RPHR-1005, the restorer line of the popular rice hybrid DRRH-3

Bacterial blight (BB) of rice caused by the pathogen Xanthomonas oryzae pv. oryzae and the insect gall midge (GM) (Orseolia oryzae) are two major constraints of rice production. The present study was carried out to improve RPHR-1005, a stable restorer line of the fine-grain-type rice hybrid DRRH-3, for BB and GM resistance through marker-assisted backcross breeding (MABB). Two major GM resistance genes, Gm4 and Gm8, and a major BB resistance gene, Xa21, were selected as target genes for transfer to RPHR-1005. Two sets of backcrosses were carried out to combine either Xa21 + Gm4 or Xa21+ Gm8 into RPHR-1005 using breeding lines in the genetic background of ISM possessing either Gm4 or Gm8 along with Xa21. Foreground selection was performed for Xa21, Gm4, Gm8, and the major fertility restorer genes Rf3 and Rf4 using gene-specific markers, while 61 polymorphic simple sequence repeat (SSR) markers were used for background selection and marker-assisted backcrossing was continued until BC2 generation. A promising homozygous backcross-derived plant at the BC2F2 generation possessing Xa21 + Gm4, and another possessing Xa21 + Gm8, were intercrossed to stack the target resistance genes. At ICF 4 (inter-crossed F4) , three promising lines possessing the three target resistance genes in a homozygous condition along with fine-grain type, complete fertility restoration, and better panicle exsertion than RPHR-1005 have been identified. Among these, a single line, # RPIC-16-65-125, showed better yield, was highly resistant to BB and GM, was of medium–slender grain type, and had complete fertility restoration along with better panicle exsertion and taller plant type than RPHR-1005. This is the first report of combining resistance against BB and GM in the genetic background of a hybrid rice parental line.

QTL Mapping in Three Rice Populations Uncovers Major Genomic Regions Associated with African Rice Gall Midge Resistance.

African rice gall midge (AfRGM) is one of the most destructive pests of irrigated and lowland African ecologies. This study aimed to identify the quantitative trait loci (QTL) associated with AfRGM pest incidence and resistance in three independent bi-parental rice populations (ITA306xBW348-1, ITA306xTOG7106 and ITA306xTOS14519), and to conduct meta QTL (mQTL) analysis to explore whether any genomic regions are conserved across different genetic backgrounds. Composite interval mapping (CIM) conducted on the three populations independently uncovered a total of 28 QTLs associated with pest incidence (12) and pest severity (16). The number of QTLs per population associated with AfRGM resistance varied from three in the ITA306xBW348-1 population to eight in the ITA306xTOG7106 population. Each QTL individually explained 1.3 to 34.1% of the phenotypic variance. The major genomic region for AfRGM resistance had a LOD score and R2 of 60.0 and 34.1% respectively, and mapped at 111 cM on chromosome 4 (qAfrGM4) in the ITA306xTOS14519 population. The meta-analysis reduced the number of QTLs from 28 to 17 mQTLs, each explaining 1.3 to 24.5% of phenotypic variance, and narrowed the confidence intervals by 2.2 cM. There was only one minor effect mQTL on chromosome 1 that was common in the TOS14519 and TOG7106 genetic backgrounds; all other mQTLs were background specific. We are currently fine-mapping and validating the major effect genomic region on chromosome 4 (qAfRGM4). This is the first report in mapping the genomic regions associated with the AfRGM resistance, and will be highly useful for rice breeders.

Genet ic Variability and Divergence Studies for Gall Midge Resistance and Yield Components in Rice (Oryza sativa L.)

Eighteen rice genotypes were evaluated for studying genetic parameters and genetic divergence for yield contributing characters and gall midge resistance at Regional Agricultural Research Station, Jagtial, Telangana. Analysis of variance revealed the presence of significant variability in experimental material for all the traits under study. Heritability estimates and genetic advance values indicated that percent of galls, effective bearing tillers plant−1, 1000 grain weight and number of grains panicle−1 were predominantly governed by additive genes which could be improved through proper selection in desirable direction, whereas, non additive genes played dominant role in the inheritance of days to 50% flowering, plant height and panicle length which could be improved through heterosis breeding. Mahalanobis D2 analysis distributed 18 genotypes into three clusters with cluster I containing maximum number of genotypes (14). Maximum inter cluster distance (10.48) was observed between cluster II and cluster III indicating wider genetic diversity, hence, crosses involving parents belonging to these clusters likely to produce wide variability and transgressive segregants with high heterotic effects. Genotypes JGL 19607, JGL 21820, JGL 3844 (cluster II) and JGL 23745 (cluster III) exhibited least gall midge incidence which could be utilized as parents in developing gall midge resistance genotypes. 1000 grain weight and days to 50% flowering were contributed maximum (75.16%) to the total divergence which could be given due importance during hybridization and selection in segregating populations.

Analysis of SSH library of rice variety Aganni reveals candidate gall midge resistance genes.

The Asian rice gall midge, Orseolia oryzae, is a serious insect pest causing extensive yield loss. Interaction between the gall midge and rice genotypes is known to be on a gene-for-gene basis. Here, we report molecular basis of HR- (hypersensitive reaction-negative) type of resistance in Aganni (an indica rice variety possessing gall midge resistance gene Gm8) through the construction and analysis of a suppressive subtraction hybridization (SSH) cDNA library. In all, 2,800 positive clones were sequenced and analyzed. The high-quality ESTs were assembled into 448 non-redundant gene sequences. Homology search with the NCBI databases, using BlastX and BlastN, revealed that 73% of the clones showed homology to genes with known function and majority of ESTs belonged to the gene ontology category 'biological process'. Validation of 27 putative candidate gall midge resistance genes through real-time PCR, following gall midge infestation, in contrasting parents and their derived pre-NILs (near isogenic lines) revealed induction of specific genes related to defense and metabolism. Interestingly, four genes, belonging to families of leucine-rich repeat (LRR), heat shock protein (HSP), pathogenesis related protein (PR), and NAC domain-containing protein, implicated in conferring HR+ type of resistance, were found to be up-regulated in Aganni. Two of the reactive oxygen intermediates (ROI)-scavenging-enzyme-coding genes Cytosolic Ascorbate Peroxidase1, 2 (OsAPx1 and OsAPx2) were found up-regulated in Aganni in incompatible interaction possibly suppressing HR. We suggest that Aganni has a deviant form of inducible, salicylic acid (SA)-mediated resistance but without HR.

Inheritance of resistance to sesame gall midge in Uganda

Sesame gall midge, caused by Asphondylia sesami Felt, is an important constraint to sesame ( Sesamum indicum L.) production in Uganda. Few genotypes have been reported on sesame gall midge, especially hairy genotypes. However, for genetic improvement, there is need to understand the mode of resistance to sesame gall midge in these genotypes. Thirty sesame genotypes were screened for gall midge resistance, under field conditions at Ngetta Zonal Agricultural Research development Institute (ZARDI) in northern Uganda. The spreader row technique was used in order to increase insect pressure on the tested genotypes. The half diallel method 2, model 1 was used to cross 5x5 parents. The result showed that non-additive gene action was important in the inheritance of resistance to sesame gall midge. Cross analysis showed that the GCA x site and SCA x site interactions were significant (P< 0.05), indicating that the additive and non-additive gene actions simultaneously controlled the inheritance for the resistance. The estimate of heritability in narrow sense genetic coefficient of determination (analogue heritable proportion) showed that the resistance was not highly heritable. Estimates of GCA and SCA effects suggest that the parent, Local158, was the best combiner for resistance to gall midge; while the parent AjimoA1-5 was the poorest combiner for the trait. Crosses Local158 x 7029-1-2 and Sesim1 x AjimoA1-5 were the best for the resistance to sesame gall midge. The estimates of genetic effects for resistance to sesame gall midge, showed predominance of additive and additive x additive type of epistasis in the inheritance of the resistance, though dominance also had a role in the cross Sesim1 x 7020-1-2. Keywords: Asphondylia sesami , combining ability, GCA, Sesamum indicum