<div style="text-align:justify">Background: Greengram Vigna radiata (L.) Wilczek, is an important legume crop that serves as a low-cost source of protein. The bruchid (Callosobruchus spp.) is a serious storage pest affecting greengram and other pulse crops. Thus, a study was designed to investigate bruchid resistance (Callosobruchus chinensis) in inter sub-specific derived lines of greengram and to identify chemical compounds responsible for resistance. 
 
Methods: The experimental material comprised of 200 inter sub-specific derived lines of F9 generation of VBN (Gg) 2 (susceptible to bruchid) &times;&nbsp;Vigna radiata var. sublobata/2 (resistant to bruchid) and a susceptible check variety. The bruchid screening experiment was carried out in completely randomized design and replicated twice with 50 seeds in each replication by adopting no choice test. Out of 200 lines evaluated for bruchid screening, seed damage due to bruchid was less than 20 per cent in 11 lines, identified as resistant. However, three resistant lines viz., GGISC 124, GGISC 140 and GGISC 150 were taken for further confirmation for bruchid resistance and GC-MS analysis to discover the chemical compounds conferring resistance (Clarus SQ 8C, Perkin Elmer).&nbsp; 
 
Result: In confirmation screening, seed damage due to bruchid (Callosobruchus chinensis) on 30th day was less than 20 per cent in three inter sub-specific lines viz., GGISC 124, GGISC 150 (17.00%) and GGISC 140 (18.00%), whereas the susceptible check [VBN (Gg) 2] reached 100 per cent adult emergence. The three inter sub-specific lines recorded susceptibility index of 0.046 (GGISC 124), 0.047 (GGISC 140) and 0.048 (GGISC 150) and classified as resistant. The susceptible check [VBN (Gg) 2] recorded the susceptibility index of 0.085. GC-MS study was carried out in resistant lines GGISC 124, GGISC 140, GGISC 150 and susceptible check VBN (Gg) 2. The results revealed that the existence of three compounds viz., 9,12-octadecadienoic acid, methyl ester; Hexadecanoic acid, 1-(hydroxymethyl)-1, 2-ethanediyl ester and Hexadecanoic acid, 2-oxiranyl methyl ester in resistant lines conferred resistance against C. chinensis in greengram.</div>

Host Plant Resistance and Analysis of Chemical Compounds Responsible for Bruchid Resistance in Greengram Vigna radiata (L.) Wilczek

<div>Background: The legume pod borer, Helicoverpa armigera (H&uuml;bner), is one of the most damaging crop pests, including pigeonpea. Host plant resistance is a component of pest management and therefore, we standardize a nylon bag No-Choice Bioassay technique to screen for resistance to H. armigera under field conditions. 
 
Methods: Pigeonpea plants were infested with 24 h old 1, 2, 3, 4 and 5 larvae per plant inside the nylon bag. Observations were recorded on pod damage, larval survival, larval weight, pupation, adult emergence, and fecundity after 10 days. 
 
Result: Pigeonpea varieties AL-201, H03-41 and PAU-881 exhibited lower pod damage (15.89 to 19.77%) and larval weight (12.02 to 13.82 mg). The expression of resistance to H. armigera was associated with trichome density, pod wall thickness and higher amount of phenolic compounds and condensed tannins. Lower trichome density and thin pod walls and higher amounts of sugars rendered the varieties Paras, Manak and Pussa-992 more susceptible to H. armigera. Nylon bag assay can be used to screen and select pigeonpea cultivars for resistance to H. armigera.</div>

​Screening of Pigeonpea Varieties through Nylon Bag No-choice Bioassay for Host Plant Resistance to Helicoverpa armigera

<div>Background: Pigeonpea [Cajanus cajan (L.) Millsp] is one of the primary grain legume crops grown in India for its high quality vegetable protein, animal feed and fodder. It is affected by various fungal and viral diseases. Among these, leaf blight caused by Alternaria alternata is one of the most destructive diseases and recently the disease of minor importance becomes major one in Tamil Nadu. Use of resistant cultivar is the most effective, economically viable and eco-friendly tool for combating the plant diseases. The micronutrients play a key role in many physiological and biochemical functions of the plants which influences plant pathogenic interaction. The micronutrients viz., Zn.Mn,Cu and Fe found to have greater impact on reducing the plant disease severity. Developing integrated disease management strategy involving disease resistant variety, micronutrient and fungicide application would be the best sustainable method for controlling the pigeonpea leaf blight. 
 
Methods: Twenty four pigeonpea genotypes along with two local varieties viz., CO5 and CO6 were evaluated in the field for their resistance against Alternaria alternata leaf blight disease, consecutively for three years from 2015-16 to 2017-18 using the disease resistance scale ranging from 0 to 9. Field experiments were also conducted for three consecutive Kharif season from 2015 to 2018 to evaluate the efficacy of the foliar application of different micronutrients and combination fungicide viz., carbendazim 12% + mancozeb 63% on the incidence of leaf blight disease.&nbsp; 
 
Result: A total of 24 pigeonpea genotypes were screened for their resistance against leaf blight under field condition. Among these, four genotypes viz., BDN2, IPA 8F, IPA 15F and MA6 were found resistance and nine genotypes were moderately resistant and remaining 11 genotypes showed susceptible reaction to leaf blight. The results of the field experiment on micronutrient and fungicide application revealed that foliar spraying of MnSO 4 @0.2% on 30 days after sowing and carbendazim 12%+ mancozeb 63%@ 1g / lit on 45 days after sowing recorded the lowest leaf blight incidence of 8.1 PDI (Per cent Disease Index) with the highest disease reduction of 76.9% as against 35 PDI in the untreated control plot. The above treatments also recorded the highest grain yield of 905 kg/ ha as against 703 kg/ in the untreated control.</div>

<div>Management of Alternaria Leaf Blight in Pigeonpea through Host Plant Resistance and Micronutrient Application</div>

Background: Mungbean (Vigna radiata) has great socio-economic importance and is one of the main food legumes widely distributed worldwide. Yield losses caused by Root-knot nematodes (Meloidogyne spp.) have been widely recorded in mungbean growing areas. Screening for stable resistant genotypes has the potential to reduce the damage caused by the root-knot nematodes.&nbsp;&nbsp; 
 
Methods: The present investigation screening of 100 mungbean genotypes against M. javanica infection were carried out in field-laboratory during 2023. Host plant resistance sources of mungbean genotypes were identified and characterized based on number of galls, galling index (GI) and a number of egg mass index against M. javanica infection. 
 
Result:&nbsp;The result exhibited that, three accessions namely UPM 02-17, IPM 1620-6 and IPM 1718-1 were resistant to M. javanica infection having GI &plusmn; 2 and five accessions viz., PARAT M 8, PUSA 9531, RMG 353, PAU-911 and PM-2 showed moderately resistant reaction with GI &plusmn; 10 and rest of the screened genotypes were either susceptible or highly susceptible against nematode infection. Nematode development and multiplication on mungbean resistance accessions had significantly weakness in pathogenic ability and nematode infection appeared to be antibiosis that was associated with reduced nematode penetration, retardation of nematode development and impeding the giant cell formation as compared to RKN susceptible mungbean genotypes.&nbsp;

Effect of Root-knot Nematode (Meloidogyne javanica) Infection on Mungbean Genotypes: Identification and Characterization of Host Plant Resistance

<div>Background: For the management of soil borne disease like dry root rot of chickpea caused by Macrophomina phaseolina, by using fungicides alone is not feasible &nbsp;due to &nbsp;environmental and health hazards. Hence integrated management of the disease by using resistant varieties, fungicides and bio-control agents is the best alternative. So the present study was aimed to identify resistant varieties, best fungicide and bioagent for management of dry root rot in chickpea. 
 
Methods: Two hundred and twelve genotypes were screened using blotter paper technique for &nbsp;identifying resistant genotypes for dry root rot. The experiment on management of dry root rot was conducted during Kharif and Rabi of 2013-14 using a susceptible chickpea variety JG-11 with 14 treatments including control with 3 replications. 
 
Result: Of two hundred and twelve chickpea genotypes screened for host plant resistance against Macrophomina phaseolina by blotter paper technique only one genotype ie. PBG-5 showed moderately resistant reaction. Among fourteen treatments including fungicides and bioagents imposed for the management of dry root rot, seed treatment with tebuconazole @ 2 g/kg recorded lowest per cent disease incidence of 9.43, with a highest yield of 722.81 kg/ha compared to untreated control which recorded the &nbsp;highest per cent disease incidence (40.10) with a lowest mean yield of 362.02 kg/ha.</div>

<div>Management of Dry Root Rot in Chickpea (Cicer arietinum L.) Caused By Macrophomina phaseolina by Utilizing Host Plant Resistance, Fungicides and Bioagents</div>

Insights of antibiosis resistance in various chickpea cultivars against pod borer Helicoverpa armigera (Hubner) under laboratory condtions. The &nbsp;present study was carried out in order to investigate the level of resistance against H. armigera on different cultivars by adopting detach leaf and pod assay. In leaf detach assay, pooled mean of 2012 and 2013, significantly lower and maximum weight gain and percent gain recorded was 101.9 mg (88.5%); 382.3mg (317.4%), respectively for ICCV 097105 and ICCV 07306. During podding stage, lowest pod damage (%) was recorded 55 % (ICCV 92944) and highest pod damage recorded by ICC 3137, LL 550 and ICCV07306 (95 %).Highest pupal weight of one day old pupae was recorded on LL 550 (405.2 mg) and lower pupal weight in ICCV 097105 (202.4 mg). The present result &nbsp;gave clue &nbsp;for future in depth studies on weeds for developing either specific pheromone compound or repellant compound for the eco- friendly management of H. armigera.

Screening for host plant resistance to Helicoverpa armigera&nbsp;(Hubner) in chickpea using novel techniques

<div>Background: Bruchid beetle (Callosobruchus chinensis) is one of the devastating field carry over storage pest causing a huge crop loss, especially in greengram. The pre-breeding lines were developed by crossing between a cultivated variety, VBN (Gg) 2 and Vigna radiata var. sublobata, a progenitor species of greengram used as a resistant parent against bruchid. 
 
Methods: A total of 53 stabilized inter sub-specific lines along with parents were screened for bruchid resistance by &lsquo;no choice&rsquo; method with two replications. Screening parameters were recorded for all the 53 lines and were statistically analysed. Damage assessment was carried out and the three resistant lines obtained during initial screening was further confirmed.&nbsp; 
 
Result: The low seed damage per cent was observed in three lines viz., GGISC-2 (18.00), GGISC-21 (20.00) and GGISC-49 (14.00). The susceptibility index was 0.048, 0.049 and 0.048 in GGISC-2, GGISC-21 and GGISC-49, respectively and hence, classified as bruchid resistant. Delayed adult emergence, uneven adult emergence, prolonged developmental period, small and malformed adults were the other parameters observed in resistant lines. The three resistant lines identified could be further utilized in the breeding programmes for the development of bruchid resistant varieties in greengram.</div>

Host Plant Resistance for Bruchids in Pre-breeding Lines of Greengram [Vigna radiata (L.) Wilczek]

<div style="text-align: justify;">Plants are affected by an extensive range of microbes, such as fungi, bacteria, viruses, viroids, and protozoa. Over the advancement, plants have evolved to defend against pathogens by developing numerous defense mechanisms in the plant cell that respond to chemical and physical barriers, These are present in plants locally or integrally. Plants have an unacquired immunity system to battle against pathogens, such as microbe-associated molecular patterns (MAMPs) are recognized through pattern recognition receptors in a primitive immune system which intermediates the defense response. Pattern recognition receptors (PRRs) they play a major role in plant innate immune system. They encode host sensors of PRRs, they can able to detect molecules of the pathogens such as macrophages, dendritic cells, neutrophils and epithelial cells containing proteins that are present in plant immune system. In this system, they identify two classes of molecules such as pathogen-associated molecular patterns (PAMPs), which are conjoined with microbe associated molecular patterns (MAMPS), and damage-associated molecular patterns (DAMPs). These are correlated with host cells released during cell damage or cell death, these are evolved before adaptive immunity. These extracellular receptors of Pattern Recognition Receptors were first identified in plants and many plant PRRs have been identified by using genomic analysis (rice and Arabidopsis). There are six classes of R-proteins, playing the major role of plant innate immunity which help to activate a defense mechanism from different microbes. Many of plant R genes encode proteins which are nucleotide-binding site and leucine-rich repeats (NB-LRR) region that contact with pathogen effectors to cause defense responses. Pathogen infection in plants is usually limited by an accomplished defense response activated by resistance genes.</div>

Role of resistant-proteins in plant innate immunity- A review

Plant diseases pose a significant threat to global food security, leading to substantial yield losses and economic damage. In recent years, irradiation technology has emerged as a promising approach to enhance plant disease resistance. Gamma irradiation, a well-established technique, has been utilized for approximately 60 years to develop new plant varieties with improved resistance to pests and diseases. X-ray is another form of ionizing radiation, has also shown the potential in enhancing plant disease resistance. UV light, including UVB and UVC radiation, has been effective in eliminating microorganisms by damaging their DNA. Electron beam irradiation, a non-ionizing form of radiation, has been investigated for its impact on plant disease resistance. However, the implementation of irradiation technology in agriculture faces challenges such as public perception, regulatory barriers and cost-effectiveness. This review article highlights the advances in irradiation technology for plant disease resistance. It emphasizes the potential of gamma irradiation, X-ray gamma irradiation, UV light, UVB, UVC and electron beam in enhancing plant disease resistance.

Advances in Irradiation Technology for Plant Disease Resistance: A Review

<div>Background: Symbiotic associations between legumes and Rhizobia are ancient and fundamental. However, the plant growth-promoting endophytes other than Rhizobia are not yet fully explored for pulses productivity. The present study was aimed to isolate efficient endophytic bacteria from pulses, assess their diversity, screen their plant growth-promoting activities and to test their potential as bio inoculants for pulses. 
 
Methods: We have isolated several endophytic bacteria from pulse crops more specifically from blackgram (Vigna mungo) and greengram (Vigna radiata). After careful screening, 15 promising endophytic isolates were selected for this study. The identification of endophytic bacterial isolates was performed by 16S rRNA gene sequencing. The isolates were tested for their potential for the plant growth-promoting traits such as nitrogen fixation, phosphate solubilization, indole-3-acetic acid production, siderophore secretion and antifungal activity. Pot culture experiments were conducted with the screened potential endophytic cultures. 
 
Result: The 16S rRNA gene sequencing revealed that species of Enterobacter, Bacillus, Pantoea, Pseudomonas, Acromobacter, Ocrobacterium were found as endophytes in blackgram and greengram. The in vitro screening identified Bacillus pumilus (BG-E6), Pseudomonas fluorescens (BG-E5) and Bacillus licheniformis (BG-E3) from blackgram and Pseudomonas chlororaphis (GG-E2) and Bacillus thuringiensis (GG-E7) from greengram as potential plant growth-promoting endophytes. These strains showed antagonism against plant pathogenic fungi. Upon inoculation of these endophytic PGPR strains, the blackgram and greengram growth and yield got increased. Among the strains, BG-E6 recorded 14.7% increased yield in blackgram and GG-E2 accounted for a 19.5% yield increase in greengram compared to respective uninoculated control. The experimental results showed that there was a host specificity found among the endophytic bacterial cultures with pulses. The cross inoculation of endophytic strains did not perform well to enhance the growth and yield of their alternate hosts.&nbsp;</div>

Host Plant Resistance and Analysis of Chemical Compounds Responsible for Bruchid Resistance in Greengram Vigna radiata (L.) Wilczek

Screening of Pigeonpea Varieties through Nylon Bag No-choice Bioassay for Host Plant Resistance to Helicoverpa armigera

Management of Alternaria Leaf Blight in Pigeonpea through Host Plant Resistance and Micronutrient Application

Effect of Root-knot Nematode (Meloidogyne javanica) Infection on Mungbean Genotypes: Identification and Characterization of Host Plant Resistance

Management of Dry Root Rot in Chickpea (Cicer arietinum L.) Caused By Macrophomina phaseolina by Utilizing Host Plant Resistance, Fungicides and Bioagents

Screening for host plant resistance to Helicoverpa armigera (Hubner) in chickpea using novel techniques

Host Plant Resistance for Bruchids in Pre-breeding Lines of Greengram [Vigna radiata (L.) Wilczek]

Role of resistant-proteins in plant innate immunity- A review

Advances in Irradiation Technology for Plant Disease Resistance: A Review

Assessing the Plant Growth-promoting Traits and Host Specificity of Endophytic Bacteria of Pulse Crops