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Vasconcellea cauliflora plants exhibiting chlorotic spots, mottling and mosaic with yellowing on leaves were observed in Pune, India in October 2020. The disease incidence was 16%. The samples were screened for cucumber mosaic virus (CMV), papaya ringspot virus, tobacco mosaic virus and zucchini yellow mosaic virus using ELISA. Sap inoculation on healthy V. cauliflora plants using CMV positive DAS-ELISA samples reproduced field symptoms. The transmission upon mechanical inoculation was 100%. For further confirmation, RT-PCR was carried out using CMV coat protein gene specific primers. Amplicons of expected size (c. 650 bp) were obtained in all symptomatic and sap inoculated samples. No amplification was observed in the asymptomatic samples. BLASTn analysis revealed that the amplicon sequence shares more than 99% identity with CMV isolates and in phylogenetic analysis it clustered with CMV IB isolates. This is the first record of V. cauliflora as a natural host of CMV worldwide. [ABSTRACT FROM AUTHOR]

Different diseases are observed in vegetables, fruits, cereals, and commercial crops by farmers and agricultural experts. Nonetheless, this evaluation process is time-consuming, and initial symptoms are primarily visible at microscopic levels, limiting the possibility of an accurate diagnosis. This paper proposes an innovative method for identifying and classifying infected brinjal leaves using Deep Convolutional Neural Networks (DCNN) and Radial Basis Feed Forward Neural Networks (RBFNN). We collected 1100 images of brinjal leaf disease that were caused by five different species (Pseudomonas solanacearum, Cercospora solani, Alternaria melongenea, Pythium aphanidermatum, and Tobacco Mosaic Virus) and 400 images of healthy leaves from India's agricultural form. First, the original plant leaf is preprocessed by a Gaussian filter to reduce the noise and improve the quality of the image through image enhancement. A segmentation method based on expectation and maximization (EM) is then utilized to segment the leaf's-diseased regions. Next, the discrete Shearlet transform is used to extract the main features of the images such as texture, color, and structure, which are then merged to produce vectors. Lastly, DCNN and RBFNN are used to classify brinjal leaves based on their disease types. The DCNN achieved a mean accuracy of 93.30% (with fusion) and 76.70% (without fusion) compared to the RBFNN (82%—without fusion, 87%—with fusion) in classifying leaf diseases. [ABSTRACT FROM AUTHOR]

Whiteflies not only damage plants directly, they also transmit phytopathogenic viruses. To facilitate whitefly studies, we made microcages from a microcentrifuge tube with a ring-shaped base of muslin and sealed the base to a leaf using wheat gum. Whitefly retention in the cages was high, leaf surfaces were not damaged during the experiment, no external support was required to hold the cages in place, and the cages worked on other crop plants. Acquisition and inoculation efficiency for begomoviruses, mungbean yellow mosaic India virus and tomato leaf curl Karnataka virus was higher in microcages than in macrocages. [ABSTRACT FROM AUTHOR]

TMV 2 is a very popular peanut variety among the Indian farmers, but it is highly susceptible to fungal foliar diseases like late leaf spot ( LLS) and rust. Marker-assisted backcrossing ( MABC) in TMV 2 using foliar disease-resistant donor, GPBD 4 and the disease resistance-linked markers ( GM2009, GM2079, GM2301, GM1839 and IPAHM103) resulted in a large number of backcross populations and also straight cross populations. Foreground selection followed by field evaluation under disease epiphytotic conditions could identify a few superior genotypes. Two homozygous backcross lines TMG-29 and TMG-46 showed enhanced resistance to LLS and rust diseases (score of 3.00 for both) along with 71.0% and 62.7% increase in the pod yield per plot, respectively, over the check, TMV 2. These foliar disease-resistant and productive lines can be released as commercial varieties or can be used as genetic resources in the peanut improvement. [ABSTRACT FROM AUTHOR]

Abstract: A new strain of Tobacco mosaic virus (TMV) was isolated from soybean (Glycine max) in India (TMV-SoyIn). It produced puckering symptoms on inoculated soybean cultivars, JS-20-30 and JS 93-05, and severe necrotic spots on inoculated leaves of Nicotiana tabacum cv. Xanthi, followed by systemic necrotic spots on subsequent leaves as well as greenish mosaic symptoms on the top leaves. In the electron microscope, tobamovirus like particles were observed in soybean leaves and also in the other inoculated host plants. The host reactions revealed that the present isolate was different from the previously described TMV strain of soybean (TMV-S) from Yugoslavia. To confirm the virus identity, the 3′ end of the genome containing the movement protein gene, coat protein and the 3′ untranslated region of the virus isolate was sequenced (1494 nucleotides; JQ895560). Results indicated that the virus associated with soybean crinkle was an isolate of TMV as the present isolate had 94.4–99.7% sequence identity with known TMV isolates. This is the first report of a TMV-strain infecting soybean in India. [Copyright &y& Elsevier]