Comunicación corta. Cultivares de algodón con resistencia moderada a African cotton mosaic virus

A 3 year screening of 25 long staple cotton cultivars for resistance to African cotton mosaic virus (ACMoV) conducted in northern Nigeria during the 1999-2001 wet seasons indicated that no cultivar was immune or resistant. Two cultivars, Pima S1 and Pima S4 were moderately resistant (16% infection), four cultivars Pima S2, Pima S3, Giza 45 and Giza 69 were moderately susceptible (31% infection), while the remaining 19 cultivars were highly susceptible. The moderately resistant cultivars are high yielding, have high quality lint characteristics such as crin percentage, bundle strength, and micronaire fineness. They can be used to reduce the menace caused by ACMoV on cotton in Nigeria.Se llevó a cabo durante tres años, durante las estaciones húmedas de los años 1999-2001, en el norte de Nigeria, una búsqueda de resistencia al African cotton mosaic virus (ACMoV) entre 25 cultivares de algodón de fibra larga. Ningún cultivar fue inmune o resistente. Dos cultivares (Pima S1 y Pima S4) fueron moderadamente resistentes (16% de infección), cuatro cultivares (Pima S2, Pima S3, Giza 45 y Giza 69) fueron moderadamente susceptibles (31% de infección) y los 19 cultivares restantes fueron altamente susceptibles. Los cultivares moderadamente resistentes dieron una producción alta y tienen una hiladura de alta calidad. Estos cultivares pueden ser utilizados para reducir la amenaza producida por ACMoV en algodón en Nigeria

First report of maize yellow mosaic virus infecting sugarcane (Saccharum spp.) and itch grass (Rottboellia cochinchinensis) in Nigeria

Article purchased; Published online: 9 May 2017During routine surveys conducted from February to July 2015 in the northern guinea savannah region of Nigeria, sugarcane and itch grass (Rottboellia cochinchinensis) plants showing virus-like mosaic symptoms were encountered in farmers’ sugarcane fields in Kaduna State. Symptomatic leaf tissue samples from five randomly selected plants (sugarcane = 4; itch grass = 1) were dried and stored under CaCl2 at room temperature then shipped to Texas A&M AgriLife Research and Extension Center, Weslaco, TX, with USDA-APHIS-PPQ permit (P526P-14-04321) for further analysis. The MagMAX-96 viral RNA isolation kit (Thermo Fisher) was used to isolate total nucleic acid (TNA) from each sample and from a sample subset consisting of pooled leaf tissue materials from both plants. TNA aliquot from the pooled sample was subjected to ribosomal RNA depletion and cDNA library construction using a TruSeq Stranded Total RNA with Ribo-Zero Plant kit (Illumina), then sequenced on the Illumina NextSeq 500 platform. The raw high-throughput sequencing (HTS) reads were analyzed as previously described (Alabi et al. 2015), generating ∼43.5 million Illumina reads (76 nucleotides [nt] in length), of which 31,486 de novo assemble

Prevalence of sorghum diseases in Nigeria

A survey was conducted in farmers’ fields in Nigeria during the 1990 cropping season to determine the prevalence of sorghum diseases in the four major sorghum‐growing climatic zones (Sahel, Sudan, northern Guinea, and southern Guinea). The foliar diseases anthracnose (Colletotrichum graminicola) oval leaf spot (Ramulispora sorghicola) sooty stripe (Ramulispora sorghi) and grey leaf spot (Cercospora sorghi) were widely distributed. Anthracnose was predominant throughout the areas surveyed with ≥40% leaf area covered or destroyed by lesions in 70% of the surveyed fields. The incidence of other foliar diseases was low. Among the panicle diseases, long smut (Tolyposporium ehrenbergii) incidence was ≤10% in ≥20% farmers’ fields in the sahelian zone. Head (Sporisorium reilianum) covered (Sporisorium sorghi) and loose (Sphacelotheca cruenta) smuts were common, but their incidence varied from 1 to 10% in the Sahel, Sudan, northern Guinea and southern Guinea zones. Survey results based on ELISA indicated for the first time in Nigeria the presence of three virus diseases of sorghum: maize mosaic (maize mosaic virus), maize stripe (maize stripe virus), and a potyvirus in the Sudan, northern Guinea, and southern Guinea zones. Grain moulds, charcoal rot (Macrophomina phaseolina) and bacterial diseases were not observed during this survey

Comunicación corta. Incidencia del virus del mosaico del kimbombó en el norte de Nigeria y evidencias de su transmisión por escarabajos

A two year survey was conducted in 2003 and 2004 in okra (Abelmoschus esculentus) plants for Okra mosaic virus (OkMV; genus Tymovirus) symptoms at three locations in northern Nigeria. It showed that the highest incidence of OkMV occurred at Samaru (16.50 and 17.10% in 2003 and 2004, respectively), followed by Shika (13.02 and 14.82%) and Bomo (12.31 and 8.10%). Disease severity followed the same trend. Beetles of Podagrica spp. naturally infected were efficient vectors in the transmission of OkMV.En 2003 y 2004 se llevó a cabo una prospección de síntomas del virus del mosaico del kimbombó (OkMV, género Tymovirus) en plantas de kimbombó (Abelmoschus esculentus) en tres localidades del norte de Nigeria. La incidencia de OkMV más alta se detectó en Samaru (16,50 y 17,10% en 2003 y 2004, respectivamente), seguido de Shika (13,02 y 14,82%) y Bomo (12,31 y 8,10%). En las tres localidades la severidad de la enfermedad siguió la misma tendencia. Escarabajos de Podagrica spp. naturalmente infectados fueron vectores eficientes en la transmisión de OkMV

Survey for incidence of "Okra mosaic virus" in northern Nigeria and evidence for its transmission by beetles: short communication

En 2003 y 2004 se llevó a cabo una prospección de síntomas del virus del mosaico del kimbombó (OkMV, género Tymovirus) en plantas de kimbombó (Abelmoschus esculentus) en tres localidades del norte de Nigeria. La incidencia de OkMV más alta se detectó en Samaru (16,50 y 17,10% en 2003 y 2004, respectivamente), seguido de Shika (13,02 y 14,82%) y Bomo (12,31 y 8,10%). En las tres localidades la severidad de la enfermedad siguió la misma tendencia. Escarabajos de Podagrica spp. naturalmente infectados fueron vectores eficientes en la transmisión de OkMV.A two year survey was conducted in 2003 and 2004 in okra (Abelmoschus esculentus) plants for Okra mosaic virus (OkMV; genus Tymovirus) symptoms at three locations in northern Nigeria. It showed that the highest incidence of OkMV occurred at Samaru (16.50 and 17.10% in 2003 and 2004, respectively), followed by Shika (13.02 and 14.82%) and Bomo (12.31 and 8.10%). Disease severity followed the same trend. Beetles of Podagrica spp. naturally infected were efficient vectors in the transmission of OkMV

Hosts of Bemisia tabaci Genn. in Northern Nigeria

Intensive surveys conducted at Samaru and its environs in the northern Guinea Savanna of Nigeria between October 2000 and September 2002, indicated that Bemisia tabaci (Genn.) infests forty two (thirty three cultivated and seven wild) species of plants. Twenty nine of the plants were found in upland, two in the lowland and eleven in both upland and lowland (fadama) areas. Heavily infested plants were distorted, chlorotic and stunted. Symptoms of virus infection were associated with some of the infested plants. This is the first comprehensive report of hosts of B. tabaci in Nigeria

Analysis of Serological Variability and Hierarchical Distribution of Rice yellow mottle Sobemovirus Isolates in Northern Nigeria

ABSTRACT A panel of four monoclonal antibodies (MAbs) was used to study the immunological profile of Rice yellow mottle virus (RYMV) genus Sobemovirus. Serological profiles of 35 representative isolates of RYMV from Borno, Gombe, Kaduna, Kano, Niger, Sokoto and Zamfara states in Northern Nigeria. All the RYMV isolates were classified into three major serogroups (SG1, SG2 and SG3) and further separated into six subgroups (Sg1a, Sg1b, Sg2a, Sg2b, Sg3a and Sg3b). The results demonstrate a significant serological variability among RYMV isolates in Northern Nigeria. The hierarchical analysis of the serological profiles data revealed high viral load in Kano, Kaduna and Gombe states, these show they are suitable locations for strategic RYMV diagnostic and field epidemiological studies