A. Legréve A. S. Reddy

Catholic University of Louvain | UCLouvain

Agricultural productivity in the Great Lakes Countries of Central Africa, including Burundi, Rwanda, and the Democratic Republic of Congo, is affected by a wide range of diseases and pests which are mainly controlled by chemical pesticides. However, more than 30% of the pesticides used in the region are banned in European Union due to their high to...

Genomic knowledge of the tree of life is biased to specific groups of organisms. For example, only six full genomes are currently available in the rhizaria clade. Here, we have applied metagenomic techniques enabling the assembly of the genome of Polymyxa betae (Rhizaria, Plasmodiophorida) RES F41 isolate from unpurified zoospore holobiont and comp...

Paper presented in section: The external environment and plant-pathogen interactions. International Congress of Plant Pathology 7th meeting (section 2.5) Edinburgh, U.K. (9 - 16 Aug. 1998)

The 3'-end region of many virus isolates has been shown to possess conserved sequences in addition to the presence of numerous genomic and subgenomic RNAs. Utilizing these sequences, a broad-spectrum reverse transcription-polymerase chain reaction protocol has been developed to detect all the known Indian peanut clump virus and Peanut clump virus i...

Since the first outbreak of Tobacco streak virus (TSV, genus Ilarvirus) on stem necrosis disease (SND)-affected sunflower in late 1990s, the virus has been a subject of much research in India. This review considers main features of TSV occurrence in India. The virus epidemics are very damaging to several crops. Natural occurrence of TSV was recorde...

The plasmodiophoromycete fungus, Polymyxa graminis was observed in the roots of Sorghum bicolor, S. sudanense, Pennisetum glaucum, Triticum aestivum, Cyperus rotundus, Eleucine coracana, Zea mays, Tridax procumbens and Arachis hypogaea collected from Indian peanut clump virus (IPCV)-infested fields. Examination of roots of IPCV-infected S. bicolor,...

Stem necrosis disease caused by Tobacco streak virus (TSV), first recognized in 2000, has emerged as a potential threat to peanut (Arachis hypogaea) in southern states of India. The virus induces severe necrosis of shoots leading to death of the plant, and plants that survive are malformed, with severe reduction in pod yield. All the currently grow...

Groundnut rosette is a major disease of groundnut (Arachis hypogaea L.) endemic to sub-Saharan Africa. The disease is restricted to the African continent and its offshore islands. It is responsible for annual groundnut yield loss worth over US$ 150 million. A complex of three agents is involved in rosette disease etiology: Groundnut rosette assisto...

In 2006, a disease characterized by mosaic mottle and yellowing symptoms was observed on groundnut (Arachis hypogaea L.) at Patancheru, Andhra Pradesh, India. Severe symptoms were restricted to a fewer leaves (Fig. 1a), which were subsequently masked with the plant growth. The disease was readily transmitted by mechanical sap inoculation from plant...

The rate of Indian peanut clump virus (IPCV, Hyderabad isolate) transmission to groundnut by mechanical inoculation was assessed using virus infected groundnut leaves and purified virus preparations from French bean and groundnut as inocula. The results showed that using French bean as inoculum source, IPCV-H could be efficiently transmitted to gro...

Tobacco streak virus (TSV) recently caused an epidemic in peanut (= groundnut, Arachis hypogaea) crops in Andhra Pradesh, India. In the epidemic area TSV occurred in many widely distributed weeds of which Parthenium hysterophorus probably plays a major role in its spread by thrips. Three thrips species, Megalurothrips usitatus, Frankliniella schult...

The progress of Indian peanut clump virus (Hyderabad isolate; IPCV-H) and its vector Polymyxa graminis in various monocotyledonous crops and groundnut was studied during the 1994, 1995 and 1996 rainy seasons in a naturally infested field in India. The roles of rainfall and temperature in the dynamics of infection by both the virus and its vector we...

A virus disease of peanut (groundnut, Arachis hypogaea L.), characterized by necrosis of the stem and terminal leaflets followed by death, caused severe crop losses in Andhra Pradesh, India during the rainy season of the year 2000. The disease was referred to as peanut stem necrosis disease (PSND). Cowpea (Vigna unguiculata, cv. C-152) and Phaseolu...

Eighty three wild Arachis germplasm accessions, belonging to 24 species of five sections and one natural hybrid derivative of a cross between the cultivated and a wild Arachis species, were evaluated along with a susceptible groundnut cultivar for resistance to Peanut bud necrosis virus (PBNV) in a replicated field trial at ICRISAT, Patancheru, Ind...

A purification procedure was developed to separate Polymyxa graminisresting spores from sorghum root materials. The spores were used as im-munogen to produce a polyclonal antiserum. In a direct antigen coating enzyme-linked immunosorbent assay (DAC ELISA), the antiserum could detect one sporosorus per well of the ELISA plate. In spiked root samples...

The RNA-2 molecule of an isolate of the L serotype of Indian peanut clump virus (IPCV) was shown to consist of 4,290 nucleotides with five open reading frames (ORF). The arrangement of the ORFs resembled that in RNA-2 of Peanut clump virus (PCV) from West Africa. The proteins encoded by the ORFs in IPCV-L RNA are between 32% and 93% identical to th...

The host range of Indian peanut clump virus (IPCV) was studied under natural infectious conditions on pearl millet, finger millet, sorghum, maize, wheat, barley, rice and groundnut plants sown in a IPCV-infested field and sampled at regular intervals. Plants were analyzed directly after sampling or transplanted in glasshouse for 6 weeks and than an...

An enzyme-linked immunosorbent assay (ELISA) procedure was developed to test peanut seed for Indian peanut clump virus (IPCV). A double antibody sandwich form of ELISA detected the Hyderabad isolate (IPCV-H) in seed of peanut. Correlation was established between the results from ELISA performed on cotyledons of peanut seed and grow-out tests. Seed...

Two strains of whitefly-transmitted cowpea mild mottle virus (CPMMV) causing severe (CPMMV-S) and mild (CPMMV-M) disease symptoms in peanuts were collected from two distinct agro-ecological zones in India. The host-range of these strains was restricted to Leguminosae and Chenopodiaceae, and each could be distinguished on the basis of symptoms incit...

Peanut bud necrosis disease (PBND) was first recorded in India in 1949. The economic importance of the disease was realized during the late 1960s when incidences up to 100% were recorded in many groundnut-growing regions in India. The disease has been described under different names. It was shown to be economically important in parts of Tamil Nadu,...

Fifty four wild Arachis germplasm accessions were evaluated for resistance to peanut stripe virus (PStV) by mechanical, aphid, and graft inoculations. Three weeks after inoculation, inoculated and subsequently produced leaflets of each entry were tested for PStV presence by enzyme-linked immunosorbent assay (ELISA). Peanut accessions in the section...

A disease of peanut characterized by stunting of plants, veinal chlorosis, outward bending of leaflets, and proliferation of axillary buds has been observed in several parts of Peninsular India since 1977. The disease was restricted to peanut crops raised during the post-rainy season. A rhabdovirus was associated with this disease. This appears to...