A field experiment was conducted to evaluate the performance of wheat genotypes against spot blotch disease from November 2016 to April 2017. Experimental field was designed in Alpha Lattice Design with 2 replications and 20 genotypes as treatments. Area Under Disease Progress Curve (AUDPC) value, days to heading, days to maturity, plant height, spike per m2, grain per spike, Thousand Kernel Weight (TKW), grain yield were examined. Negative correlation was observed between yield of different genotypes and AUDPC i.e. -0.17322. Genotype BL 4699 and NL 1247 were found to be resistant with AUDPC value 141.7 and 140.6 and yield 3.335MT/ha and 3.604MT/ha respectively. Similarly, genotype BL 4708, NL 1327 and BL 4707 were found to be tolerant with AUDPC value 567.2, 570.6 and 274.6 and yield 3.761MT/ha, 3.642MT/ha and 3.681Mt/ha respectively. So, resistant and tolerant genotypes BL 4699, NL 1247, BL 4708, NL 1327 and BL 4707 could be suggested to incorporate into the breeding program.

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Lesion mimic creates necrosis in the leaf tissue and promotes the growth of necrotrophic/hemibiotrophic pathogens. The presence of lesion mimic locus and their effect on spot blotch disease, days to heading, black point index and thousand kernel weight of wheat were investigated in parents Sujata, Avocet-YRA and their 146 recombinant inbred lines (RILs). The study conducted during two cropping seasons showed that some lines with higher expression of lesion mimic phenotypes exhibited significant increase in AUDPC. Three markers (Xbarc181, Xwmc674 and Xgwm513) were deployed to reveal the presence of lesion mimic locus (lm, lm1 and lm2). Three lesion mimic loci were detected in combinations of lm+lm1+lm2, lm+lm2, lm2 and lm. The three loci combination (lm+lm1+ lm2) expressed highest lesion mimic severity and early heading while lowest expression was recorded in the RILs with lm2 locus alone. Lesion mimic grade showed positive and significant correlation with AUDPC and negatively significant association with days to heading. Black point index and thousand kernel weight was not correlated with the lesion mimic grade. These lm loci expression showed differential production of ROS and were characterized by DAB and NBT staining. The combination of the three loci showed increased accumulation of H 2 O 2 and O 2 − while genotypes with only lm locus showed reduced accumulation. The microsatellite markers identified in this study may be useful for evaluating whether proposed parents with n.ormal phenotype are carriers of lesion-mimic alleles and could be of interest in breeding wheat for disease resistance.

Alternaria leaf spot caused by Alternaria brassicicola is one of the destructive diseases of crucifers and causes considerable loss in the yield and quality of the produce. An experiment was conducted in in vitro to evaluate the efficacy of six botanical extracts at three concentrations i.e. 5%, 10% and 15%, six chemical fungicides at five different concentrations i.e. 50ppm, 100ppm, 250ppm, 500ppm and 1000ppm and Trichoderma harzianum against Alternaria brassicicola. The study was carried out using poisoned food technique for botanical extracts and chemical fungicides and dual culture technique for T. harzianum in Completely Randomized Design (CRD). Among botanical extracts, maximum inhibition (99.91%) of mycelial growth was observed in sweet flag at 15% concentration followed by 10% sweet flag (96.68%) and 5% sweet flag (93.64%) and minimum inhibition percent (5.61%) was observed in Lantana camara at 5% concentration. Hexaconazole proved to be the most effective chemical fungicide recording 100% growth inhibition at all the tested concentrations which was at par with1000 ppm metalaxyl + mancozeb (Kriloxyl Gold), 500 and 1000 ppm mancozeb and 1000 ppm carbendazim + mancozeb(SAAF)whereas, 50 ppm carbendazim was least effective in reducing fungal growth (7.16%). T. harzianum showed 65.02% inhibition of test fungus. The study indicated better performance of some chemical fungicides even at lower concentrations i.e. 100ppm and 250ppm. So, such effective fungicides could be used to minimize hazardous effect. Significant effect of some botanical extracts against pathogen growth suggests their application as potential control agent alternative to chemicals.

Foliar fungal diseases in tomatoes include early blight (Alternaria linariae), Septoria leaf spot (Septoria lycopersici), and late blight (Phytophthora infestans) which is oomycetes. These are one of the significant production constraints in tomatoes. We describe the etiology, host range, distribution, symptoms, and disease cycle to understand the biology followed by management practices emphasizing the resistance breeding approach for these diseases. In crop improvement efforts, we provide an analytical review, including conventional and molecular methods for improving this disease resistance. Modern breeding tools, including genomics, genetic transformation, and genome editing, can be used to improve these traits. There is a good possibility of using these tools in the future to improve these traits.