Deriving appropriate pest management technologies for smallholder tomato (Solanum lycopersicum Mill.) growers: A case study of Morogoro, Tanzania

Journal of Animal & Plant Sciences, 2010. Vol. 6, Issue 3: 663- 676. Publication date: 28/04/2010,The current standard farmer practice for insect pests and disease control in tomatoes is routine weekly pesticide sprays which are not always required. Field experiments were conducted at Morogoro, Tanzania to evaluate the effect of seven management practices (sub plots) on pest incidence and yields during May-September 2007 (normal production season) and October 2007 - February 2008 (off-season) using two determinate varieties CALJ and Tanya (main plots) in a RCBD with five replications. Practices involving intercropping with Vigna unguiculata or Cleome gynandra, application of fertilizer or mulch were severely infested by insects particularly thrips (Frankinlla occidentalis) which averaged 30 insects/plant at 64 days after transplanting. The standard and integrated pest management (IPM) practices led to similar low levels of insect pest and disease control though in the IPM only 3 pesticide sprays were applied compared to 10 for the standard practice. In the normal season, disease incidences of early blight (Phytophthrora infestans), late blight (Altenaria solani), leaf spot (Septoria lycopersici) and leaf curl were low (<10%) except for fertilizer and mulch treatment where incidences were close to 50%. The greatest fruit damage (>50%) was ascribed to Helicoverpa armigera. Purple nutsedge (Cyperus rotundus), the most dominant weed, was initially controlled by pre-transplanting application of Round-up® and mulch suppressed the growth of the dominant broadleaf weeds Digera muricata (false amaranth); Amaranthus spp (pigweeds) and Commelina benghalensis (wondering jew). In the normal season, tomato yields with current farmer practice were highest averaging 18.5 t/ha which was not significantly different (P=0.05) from mulch application (14 t/ha) followed by IPM (12.1 t/ha). Similarly, in the off-season crop, yields were highest and similar for mulch and standard practice (4.8 t/ha) followed by IPM (3.4 t/ha). Farmers selected mulch application and IPM for on-farm demonstration to verify production costs and benefits

Deriving appropriate pest management technologies for smallholder tomato (Solanum lycopersicum Mill.) growers: A case study of Morogoro, Tanzania

Journal of Animal & Plant Sciences, 2010. Vol. 6, Issue 3: 663- 676. Publication date: 28/04/2010,The current standard farmer practice for insect pests and disease control in tomatoes is routine weekly pesticide sprays which are not always required. Field experiments were conducted at Morogoro, Tanzania to evaluate the effect of seven management practices (sub plots) on pest incidence and yields during May-September 2007 (normal production season) and October 2007 - February 2008 (off-season) using two determinate varieties CALJ and Tanya (main plots) in a RCBD with five replications. Practices involving intercropping with Vigna unguiculata or Cleome gynandra, application of fertilizer or mulch were severely infested by insects particularly thrips (Frankinlla occidentalis) which averaged 30 insects/plant at 64 days after transplanting. The standard and integrated pest management (IPM) practices led to similar low levels of insect pest and disease control though in the IPM only 3 pesticide sprays were applied compared to 10 for the standard practice. In the normal season, disease incidences of early blight (Phytophthrora infestans), late blight (Altenaria solani), leaf spot (Septoria lycopersici) and leaf curl were low (<10%) except for fertilizer and mulch treatment where incidences were close to 50%. The greatest fruit damage (>50%) was ascribed to Helicoverpa armigera. Purple nutsedge (Cyperus rotundus), the most dominant weed, was initially controlled by pre-transplanting application of Round-up® and mulch suppressed the growth of the dominant broadleaf weeds Digera muricata (false amaranth); Amaranthus spp (pigweeds) and Commelina benghalensis (wondering jew). In the normal season, tomato yields with current farmer practice were highest averaging 18.5 t/ha which was not significantly different (P=0.05) from mulch application (14 t/ha) followed by IPM (12.1 t/ha). Similarly, in the off-season crop, yields were highest and similar for mulch and standard practice (4.8 t/ha) followed by IPM (3.4 t/ha). Farmers selected mulch application and IPM for on-farm demonstration to verify production costs and benefits

A large genome-wide association study of age-related macular degeneration highlights contributions of rare and common variants

Advanced age-related macular degeneration (AMD) is the leading cause of blindness in the elderly, with limited therapeutic options. Here we report on a study of >12 million variants, including 163,714 directly genotyped, mostly rare, protein-altering variants. Analyzing 16,144 patients and 17,832 controls, we identify 52 independently associated common and rare variants (P < 5 × 10 -8) distributed across 34 loci. Although wet and dry AMD subtypes exhibit predominantly shared genetics, we identify the first genetic association signal specific to wet AMD, near MMP9 (difference P value = 4.1 × 10 -10). Very rare coding variants (frequency <0.1%) in CFH, CFI and TIMP3 suggest causal roles for these genes, as does a splice variant in SLC16A8. Our results support the hypothesis that rare coding variants can pinpoint causal genes within known genetic loci and illustrate that applying the approach systematically to detect new loci requires extremely large sample sizes. © 2016 Nature America, Inc