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During seed health testing of 160 accessions of safflower, we observed some fungal growth on seed surface of four accessions i.e., IC337954, IC338197, EC182199 and EC181301 which were received from Hyderabad, Telangana, India for long‐term conservation in the National Genebank, ICAR‐National Bureau of Plant Genetic Resources, New Delhi, India. The associated fungus was morphologically identified as Diaporthe helianthi. Later on, the identity was confirmed as Diaporthe helianthi (Desm.) Grove by the sequencing of internal transcribed spacer (ITS) region (GenBank Id: KM979906.1). During seed health testing, seed infection of 30.0 to 70.0 per cent was recorded with no seed germination in infected seeds. Previous findings revealed that D. helianthi is host‐specific pathogen causing stem canker to sunflower only and the fungus is seed‐borne. As a destructive pathogen causing substantial yield losses, especially to sunflower, it may be a serious threat to safflower cultivation in the country and anywhere else. Therefore, the detection and identification of D. helianthi can be helpful in alarming the threat at an early stage thereby minimizing the probable damage to safflower cultivation in near future. [ABSTRACT FROM AUTHOR]

Various seed treatment combinations comprising insecticide, fungicide, and a biocontrol agent along with foliar sprays of insecticides were evaluated for the management of leaf crinkle ( Urdbean leaf crinkle virus [ULCV]), yellow mosaic ( Mungbean yellow mosaic virus [MYMV]), and wet root rot (WRR; Rhizoctonia solani ) diseases of urdbean ( Vigna mungo ) under field conditions. Seed treatment with a combination of imidacloprid, carboxin + tetramethylthiuram disulfide (TMTD), and Pusa 5SD ( Trichoderma virens ) provided the highest seed germination (77.5%) and grain yield (953.3 kg/ha) with the lowest WRR (3.7%), mungbean yellow mosaic (MYM, 17.2%), urdbean leaf crinkle (ULC, 12.1%) diseases, and whitefly population (13.5–6.7 per plant). Among foliar sprays, the first spray of imidacloprid at 30 days after sowing (DAS) followed by the second spray of spinosad at 45 DAS showed less disease development (10.6% MYM and 7.5% ULC diseases) and whitefly populations (21.2–2.1 per plant) with the highest grain yield (1035.4 kg/ha). Among the interactions of seed treatment and foliar spray, a combination of seed treatment with imidacloprid, carboxin + TMTD, and Pusa 5SD ( T. virens ) and foliar sprays of imidacloprid and spinosad at 30 and 45 DAS, respectively, provided the lowest incidence of all three diseases (2.9% WRR, 7.0% yellow mosaic, and 4.2% leaf crinkle diseases) and whitefly populations (11.7–1.0 per plant) along with the highest grain yield (1258.6 kg/ha). Identical seed treatments may be combined with foliar sprays of dimethoate and spinosad at 30 and 45 DAS, respectively. These seed treatments and foliar sprays individually and in combinations reduced the whitefly populations responsible for the spread of the viral diseases. [ABSTRACT FROM AUTHOR]

Karnal bunt caused by Tilletia indica is a quarantine disease responsible for qualitative and quantitative losses in wheat. The present study aimed to determine the expression of defense-related genes involved in early stages of infection in response to T. indica by using the differential display reverse transcriptase-PCR method (DDRT-PCR) in susceptible (WL 711) and resistant (HD 29) cultivars of wheat. The DDRT-PCR banding profiles generated by the random primers in combination with oligo-dT primers of resistant and susceptible wheat plants were evaluated at 0 h, 12 h, 24 h, and 48 h after inoculation. Out of 9 sets of primers, 7 sets of primers produced remarkable induced transcripts. The highest up-regulated transcripts were observed in the resistant cultivar (HD 29), whereas the down-regulated transcripts were found in the susceptible (WL 711) cultivar. Several sets of primers were designed from the defenserelated gene sequences available in the GenBank database, and of these, 4 primer sets amplified the desired specific bands. Based on the putative functions, 3 defense-related genes, namely puroindoline protein PINB (AT_KB2), ß-1,4-glucanase (AT_KB3), and chitinase (AT_KB7), and 1 housekeeping gene, actin (AT_KB1), were characterized. [ABSTRACT FROM AUTHOR]

Wilt caused by the fungusFusarium oxysporumf. sp.cicerisadversely affects the productivity of cultivated chickpea. For the management of this disease, seed and soil application formulations developed from another fungus,Trichodermaspecies, were evaluated. In pot experiments,T. harzianum-based formulations Pusa 5SD for seed dressing and Pusa Biopellet (PBP) 10G and Pusa Biogranule (PBG) 5 for soil application, andT. viride-based formulations Pusa 5SD for seed dressing and PBP 4G and PBG 4 for soil application, were found to be highly effective against the disease. A combination of PBP 4G (T. viride) for soil application and Pusa 5SD (T. harzianum) for seed treatment together with a fungicide, carboxin, provided the highest seed germination, shoot and root lengths and grain yield with the lowest incidence of wilt in chickpea under field conditions. Individually, soil application of PBP 4G, and seed treatment with Pusa 5SD were effective in reducing the incidence of wilt and increasing the grain yield of chickpea, but their effectiveness was greater when applied as a combination. Thus, combined application of the formulations of two different species ofTrichodermain two modes of application is recommended for the management of chickpea wilt. [ABSTRACT FROM PUBLISHER]

Genetic variability in 23 monosporidial lines developed from five isolates of Tilletia indica causing Karnal bunt of wheat isolated from four wheat growing states of India was determined by using 19 rapid amplified polymorphic DNA (RAPD) markers. Amplification profile generated with all the 19 primers produced 3-16 numbers of bands of 1.5-5 kb size. High level of polymorphism (95.2%) suggested wide range of variability. Maximum Jaccard's similarity coefficient (80%) was observed between KB2MsB and KB2MsC followed by KB5MsC and KB5MsE with 75% similarity, whereas it was minimum between KB3MsA and Kb4MsB (47%). The dendrogram derived from the fingerprint analysis with 19 RAPD primers by using UPGMA showed different levels of genetic similarity among monosporidial lines. At 35% genetic similarity, the monosporidial lines were grouped in two clusters. Some primers, viz., OPN-1, OPN-6, OPN-9, OPN-12, OPN-13, OPN-18, OPM-2, OPM-8, OPM-10, OPB-8, OPB-17 and OPB-20 showed 100% polymorphism. The RAPD fingerprint generated by OPN-1 and OPM-3 were analysed and showed high range of variation in genetic make-up of monosporidial lines. [ABSTRACT FROM AUTHOR]

Tilletia indica Mitra is the causal agent of Karnal bunt of wheat, an important disease prevalent in several countries. The disease is internationally quarantined and the pathogen due to its heterothallic nature shows high variability. In the present study, we compared the pathogenic behaviour of various isolates of T. indica collected from different geographical locations of India and genetically characterized monosporidial (Ms) culture lines raised from these isolates of the pathogen. Pathogenic variability revealed existence of three pathotypes based on aggressiveness on a set of differential host genotypes. Monosporidial culture lines viz., 5 each from KB1, KB2, KB4 and KB5 and three lines of KB3 were established and analyzed genetically using 12 Universal Rice Primers (URPs). Amplification showed 98.44% polymorphism and primer URP 13R produced 100% polymorphic bands. Maximum similarity (83%) was between KB1MsB and KB1MsD as calculated by Jaccard's similarity coefficient, whereas, minimum similarity was between KB1MsC and KB4MsB; KB1MsE and KB3MsA (46%). Three groups were formed among all Ms culture lines. One major group consisted of 13 lines with approximately 70% similarity, the second group consisted of 7 culture lines showing 55% similarity and the third group consisted of 3 Ms lines. URPs were able to differentiate the Ms culture lines raised from different T. indica isolates and the results indicated heterogeneity in the pathogen population. [ABSTRACT FROM AUTHOR]