ELISA: An Inexpensive and highly precise tools for estimation of aflatoxins

Agricultural products are often at risk of fungal invasion that can produce toxic metabolites called “mycotoxins”. Aflatoxins:Among these, aflatoxins are of economic importance because of their influence on the health of human beings and livestock, and on the marketability of agricultural products. It is essential to analyze food products to ensure their safety. In most developing countries limited or no facilities exist for monitoring these toxins in foods and feeds. They are based on physicochemical methods such as thin layer chromatography (TLC), and high performance liquid chromatography (HPLC). However, these are very expensive and may not be available everywhere..

Characterization of plant growth-promoting and disease suppressing abilities of certain actinomycetes isolated from groundnut rhizosphere.

Susceptibility to several biotic constraints, including fungal and viral diseases, is one of the major reasons for low productivity in peanut. This situation is common in several developing countries in Asia and Africa, where resource poor farmers cannot afford expensive chemical pesticides for disease management. With an objective to identify sources of multiple disease resistance in peanut, ICRISAT’s peanut mini core collection (10% of core or 1% of entire collection) consisting 184 accessions was evaluated independently for two important fungal foliar diseases such as late leaf spot (LLS) and rust under field conditions during 2012 rainy season. The same set was evaluated for peanut bud necrosis disease (PBND) under late planting in the field during 2012 rainy season. Results indicated that 8 accessions showed less than 1% PBND incidence, and two accessions (ICG 2019, ICG 13858) were completely immune, compared to the average disease incidence of 25% in the trial and 40% in the susceptible control. In the rust screening trial, 3 accessions (ICG 6022, ICG 11088 and ICG 11426) were highly resistant (<3.0 rating on a 1-9 disease rating scale) and coupled with superior yields of more than 3.0 t/ha. In the LLS screening trial, ICG 11426 was highly resistant with a rating of 3.0 on a 1-9 disease rating scale, with a yield of 3.8 t/ha.These accessions can be used further in pe

Management of Soilborne Diseases in Crop Plants: An Overview

Soilborne diseases are very critical in realizing the yield potential of improved cultivars in several agricultural crops. Often these diseases are very difficult to manage due to their highly heterogeneous incidence and lack of knowledge on the epidemiological aspects of soilborne pathogens. Soilborne diseases of ancient and modern agricultural crops have always had some impact on growth and productivity. Observations and experience passed down through generations gave rise to cultural practices that reduced or minimized the losses to soilborne and above ground diseases, but it was probably rare that anyone in agriculture claimed to “control” the diseases. The expansion in the crop diversity in agriculture has required parallel expansion of strategies to minimize the soilborne diseases. The effective control of the soilborne diseases is possible only through detailed study on survival, dissemination of soilborne pathogens; effect of environmental conditions role of cultural practices and host resistance and susceptibility will play a major role in disease management

Reaction of Groundnut Advanced Breeding lines to Groundnut Bud Necrosis Disease

Forty advanced breeding lines were evaluated for reaction to Groundnut bud necrosis orthotospovirus (GBNV) in the field and greenhouse in Hyderabad, India during2013 rainy season. Results from natural infection showed eight resistant, 24 moderately resistant and eight moderately susceptible genotypes. There were no genotypes pertaining to highly resistant, susceptible and highly susceptible disease reaction grade. Greenhouse screening with mechanical sap inoculation showed all genotypes highly susceptible at 1:10 infected virus extract dilution, whereas at 1:100, two genotypes were moderately resistant, four moderately susceptible, ten susceptible and 24 highly susceptible. There were no genotypes pertaining to highly resistant and resistant disease reaction grade even at 1:100 infected virus extract dilution

Peanut mini core collection at ICRISAT: A reality in identifying multiple disease resistance sources

Susceptibility to several biotic constraints, including fungal and viral diseases, is one of the major reasons for low productivity in peanut. This situation is common in several developing countries in Asia and Africa, where resource poor farmers cannot afford expensive chemical pesticides for disease management. With an objective to identify sources of multiple disease resistance in peanut, ICRISAT’s peanut mini core collection (10% of core or 1% of entire collection) consisting 184 accessions was evaluated independently for two important fungal foliar diseases such as late leaf spot (LLS) and rust under field conditions during 2012 rainy season. The same set was evaluated for peanut bud necrosis disease (PBND) under late planting in the field during 2012 rainy season. Results indicated that 8 accessions showed less than 1% PBND incidence, and two accessions (ICG 2019, ICG 13858) were completely immune, compared to the average disease incidence of 25% in the trial and 40% in the susceptible control. In the rust screening trial, 3 accessions (ICG 6022, ICG 11088 and ICG 11426) were highly resistant (<3.0 rating on a 1-9 disease rating scale) and coupled with superior yields of more than 3.0 t/ha. In the LLS screening trial, ICG 11426 was highly resistant with a rating of 3.0 on a 1-9 disease rating scale, with a yield of 3.8 t/ha.These accessions can be used further in peanut breeding programs for developing multiple disease resistant high yielding cultivar

DNA Cloning and Sequencing

The plasmid DNA is cleaved with an enzyme and joined in vitro to foreign DNA; the resulting recombinant plasmids are then used to transform bacteria. The plasmid vectors must be carefully chosen and processed to minimize the effort required to identify and characterize recombinants. This chapter provides guidelines for preparation of DNA fragment for cloning, transformation into chemically competent host, and selection of positive clones. The write-up will also describe basic methods used in the cloning of PCR amplified rRNA gene into appropriate vector and followed by sequencing

Streptomyces sp. RP1A-12 mediated control of peanut stem rot caused by Sclerotium rolfsii

Sclerotium rolfsii Sacc. is a destructive soilborne fungal pathogen with a wide host range that includes peanuts. Biological control offers an interesting alternative to fungicides for sustainable management of soilborne diseases. The current investigation is aimed at evaluating one potential biocontrol agent Streptomyces sp. RP1A-12 for growth promotion and the management of peanut stem rot disease caused by S. rolfsii under field conditions. Preliminary studies conducted under in vitro and greenhouse conditions showed promising results against the stem rot pathogen. Further in vitro and pot experiments conducted to assess Streptomyces sp. RP1A-12 for its growth promoting abilities using whole organisms have shown an increase in seed germination, root and shoot length. Other parameters like nodule number and plant biomass were also significantly increased over control treatments indicating that the test bioagent possesses growth promoting abilities along with disease suppression capabilities. Subsequently field studies were carried out for two consecutive rainy seasons. The bioagent was applied as whole organism and partially purified crude metabolites. Results indicate the bioagent reduced stem rot disease incidence by 64–67% and 22–49% respectively in two field trials conducted with notable increase in yield. Partially purified Streptomyces sp. RP1A-12 metabolites exhibited an even greater effect in reducing the incidence and severity of stem rot compared to the pathogen inoculated control

Role of public-private partnerships in biopesticides and biofertilizers research and development for sustaining agriculture production

Public-Private-Partnerships (PPPs) are important in involving private sectors for harnessing their efficient and enhanced mass production and delivery of consumer products and services. In agriculture, the rationale for these bilateral or multilateral collaborations is to achieve sustainability in agriculture production. In agriculture research and development (R&D), these PPPs are effective in overcoming public sector institutions limited ability in taking research products and technologies effectively to farmers. This paper emphasizes the role of PPPs in biopesticides and biofertilizers research towards attaining sustainability in agricultural production. The challenges faced by the smallholder farmers in Asia-Pacific region; the benefits of integrating modern and indigenous technologies and materials for increased food production arediscussed in the paper. Particularly, the role of Plant Growth Promoting Rhizobacteria (PGPR) in sustainable agriculture production, their mechanisms of action in controlling plant diseases and promoting crop yields were highlighted. The role of Asian PGPR Society in building fruitful collaborations among scientific institutes, private enterprises, industries and academic institutions, and thus promoting PPPs in biopesticides and biofertilizers research are discussed. Lessons learnt from PPPs such as the Hybrid Parents Research Consortia (HPRC) model established by ICRISAT; and the Bioproducts Research Consortium (BRC) partnership with ICRISAT were elaborated. The future of PGPR research and the scope of PGPR as biofertilziers and biopesticides with commercial potential in AsiaPacific region are discussed. The role of Governments in forging PPPs in R&D for biofertilizers and biopesticides as in case of is emphasized. The future role of Asian PGPR Society in accelerating and revitalizing the existing PPPs and facilitating the future partnerships in biopesticides and biofertilizer sector are discussed

Deep sequencing of Pigeonpea sterility mosaic virus discloses five RNA segments related to emaraviruses

The sequences of five viral RNA segments of Pigeonpea sterility mosaic virus (PPSMV), the agent of sterility mosaic disease (SMD) of pigeonpea (Cajanus cajan, Fabaceae), were determined using the Deep sequencing technology. Each of the five RNAs encodes a single protein on the negative-sense strand with an open reading frame (ORF) of 6885, 1947, 927, 1086, and 1422 nts, respectively. In order, from RNA1 to RNA5, these ORFs encode the RNA-dependent RNA polymerase (p1, 267.9 kDa), a putative glycoprotein precursor (p2, 74.3 kDa), a putative nucleocapsid protein (p3, 34.6 kDa), a putative movement protein (p4, 40.8 kDa), while p5 (55 kDa) has an unknown function. All RNA segments of PPSMV showed the highest identity with orthologs of fig mosaic virus (FMV) and rose rosette virus (RRV). In phylogenetic trees constructed with the amino acid sequences of p1, p2 and p3, PPSMV clustered consistently with other emaraviruses, close to clades comprising members of other genera of the family Bunyaviridae. Based on the molecular characteristics unveiled in this study and the morphological and epidemiological features similar to other emaraviruses, PPSMV seems to be the seventh species to join the list of emaraviruses known to date and accordingly, its classification in the genus Emaravirus seems now legitimate