Inhibitory activity of plant extracts on the early blight pathogen Alternaria solani

This study evaluated the effect of two plant extracts, Ricinus communis and Chromolaena odorata on the control of the early blight pathogen, Alternaria solani (Ell. and Mart.). The study was conducted in the Laboratory of the Crop Production and Horticulture Department, Federal University of Technology, Yola, Adamawa State, Nigeria. A Completely Randomized Design (CRD) replicated three times was used. Three concentrations (25%, 50%, and 100%) of each plant extract were determined for inhibitory activity of A. solani growth. From the radial growth results, it revealed that Ricinus communis at 100 % concentration was recorded for the lowest radial growth rates of 1.43 cm, 2.00 cm and 2.72 cm at 24, 48 and 72 hours were recorded, respectively. It was concluded that the plant extracts used at different concentrations showed promising prospects for control Alternaria solani growth in vitro. However, it was recommended that there is a need to evaluate the inhibitory function of the plant extracts in the field to ascertain their effectiveness

Eco-Friendly Management Strategies for Gray Leaf Spot Disease of Sorghum Using Cultivar Selection and Seed Dressing Fungicides in Maiduguri, Nigeria

Gray leaf spot is one of the most important foliage diseases of sorghum. A study on the fungicidal seed treatment and screening sorghum cultivars on gray leaf spot disease was investigated in a split plot arrangement using four seed dressing fungicides (Metalaxyl, Captan, Thiobendazole and Benomyl), untreated control and five sorghum cultivars (ICSV111, ICSV400, ICSH89002NG, ICSH89009NG and Q-L INDIA). The combined results of the two year revealed that synergistic interaction of cultivars (ICSV111, ICSV400, ICSH89002NG and ICSH89009NG) with Apron plus 50Ds significantly reduced severity at 60 DAS from 40 to 25% compared with untreated check. Similarly, Cultivars ((ICSV111 and ICSV400) with Apron plus 50Ds brought about significant reduction in logistic infection from 0.023 to 0.0006 units per day over untreated check. This further culminated into better seedling establishment and grain yield were increased

Effect of Some Environmental Factors on Incidence and Severity of Angular Leaf Spot of Cotton in Yola and Mubi, Adamawa State, Nigeria

Environmental factors such as relative humidity and rainfall generally have been found to increase the incidence, rate of spread and severity of diseases thereby reducing yield of crops. Study was conducted on five cotton varieties, which were artificially inoculated with bacterial blight pathogen to determine the effects of rainfall and relative humidity on incidence and severity of angular leaf spot (ALS) and yield of seed cotton in Yola and Mubi. Results showed that the severity of ALS was higher in Yola (58.65%) at 13 WAS assumed to be due to higher relative humidity range of 76% - 87% and low rainfall of 2 - 40.6 mm. This is assumed to have favoured disease development as against that of Mubi location which recorded lower severity (51.11%) due to lower relative humidity (42% - 55%) and rainfall (37 - 73 mm). Results further revealed that at 13 WAS, SAMCOT-8 had low incidence (66%) and severity (39%) in Yola. This was against the much higher corresponding incidence and severity of 82% and 42% respectively that was observed in Mubi during the same period. SAMCOT-10 and SAMCOT-9 varieties were found to be highly susceptible to the disease at the same period. SAMCOT-8 recorded the highest yield of 390.00 kg?ha?1 in Yola and 868.09 kg?ha?1 in Mubi while the lowest yields of 227.17 kg?ha?1 was observed on SAMCOT-10 in Yola while 461.61 kg?ha?1 was obtained on SAMCOT-9 in Mubi. The variation in yield among these varieties might be due to the differences in their reactions to the disease. There is a need to conduct further trials in these locations to confirm the level of resistance or other aspects of these varieties to the disease

Growth of Sesame as Influence by Varieties and Plant Extracts on the Control of Cercospora sp. in Ardo-Kola and Gassol, Taraba State, Nigeria

Field trial was conducted at Ardokola (Latitude 080 53′N and Longitude 110 19′E) and Gassol (Latitude 08o 31′N and Longitude 10o 33′E) 2012 to investigate the influence of four cultivars (Yandev 55, NCRIBEN 01M, E8 and NCRIBEN-03L) and five plant extracts (Azadirachtaindica, Jatrophacurcas Linn., Aliumsativum,Ocimumgratissimum(L.,Chromolaenaodorata) and Benomylincluding unsprayed control on Cercosporasesami on sesame growth parameters. The trial was designed using randomized complete block design (RCRD) in a split plot arrangement in allocating treatments to plots which was replicated four times. In both locations sesame plants were sprayed with 10% extracts once in every two weeks using hand sprayer from 4 to 10 weeks after sowing. Results obtained showed that plant extracts (Ocimum, Chromolaena), which had statistical similarities with Benlate help to significantly reduced incidence of infection of Cercospora leaf spot (CLS) disease on sesame and slow down epiphytotic rate of progress, which subsequently resulted in to significant increase in plant height (cm) and branches per plant at both locations. Furthermore, variety E8 was found to be resistant to Cercospora leaf spot. Similarly, interaction effect indicated that E8 seedlings sprayed with plant extract from Ocimumgratissimum and Chromolaenaodorata gave the lowest incidence and infection rate, compared with the highest disease obtained from unsprayed plants of Yandev 55 variety. This had resulted in highest increase of plant height (cm) and branches per plant. From this study it could be seen that the performance of the plant extracts is comparable to the synthetic fungicide Benomyl, and therefore this has given the farmers ample opportunities to try many alternatives that are user friendly. Therefore, plant extracts and crop varieties can be used as a potential tool in plant disease management, particularly Cercospora leaf spot of sesame, as sustainable and ecofriendly botanical fungicides that are economically and environmentally rewarding for sesame and other crop producers

Growth of Sesame as Influence by Varieties and Plant Extracts on the Control of Cercospora sp. in Ardo-Kola and Gassol, Taraba State, Nigeria

Field trial was conducted at Ardokola (Latitude 080 53′N and Longitude 110 19′E) and Gassol (Latitude 08o 31′N and Longitude 10o 33′E) 2012 to investigate the influence of four cultivars (Yandev 55, NCRIBEN 01M, E8 and NCRIBEN-03L) and five plant extracts (Azadirachtaindica, Jatrophacurcas Linn., Aliumsativum,Ocimumgratissimum(L.,Chromolaenaodorata) and Benomylincluding unsprayed control on Cercosporasesami on sesame growth parameters. The trial was designed using randomized complete block design (RCRD) in a split plot arrangement in allocating treatments to plots which was replicated four times. In both locations sesame plants were sprayed with 10% extracts once in every two weeks using hand sprayer from 4 to 10 weeks after sowing. Results obtained showed that plant extracts (Ocimum, Chromolaena), which had statistical similarities with Benlate help to significantly reduced incidence of infection of Cercospora leaf spot (CLS) disease on sesame and slow down epiphytotic rate of progress, which subsequently resulted in to significant increase in plant height (cm) and branches per plant at both locations. Furthermore, variety E8 was found to be resistant to Cercospora leaf spot. Similarly, interaction effect indicated that E8 seedlings sprayed with plant extract from Ocimumgratissimum and Chromolaenaodorata gave the lowest incidence and infection rate, compared with the highest disease obtained from unsprayed plants of Yandev 55 variety. This had resulted in highest increase of plant height (cm) and branches per plant. From this study it could be seen that the performance of the plant extracts is comparable to the synthetic fungicide Benomyl, and therefore this has given the farmers ample opportunities to try many alternatives that are user friendly. Therefore, plant extracts and crop varieties can be used as a potential tool in plant disease management, particularly Cercospora leaf spot of sesame, as sustainable and ecofriendly botanical fungicides that are economically and environmentally rewarding for sesame and other crop producers

Effect of Some Environmental Factors on Incidence and Severity of Angular Leaf Spot of Cotton in Yola and Mubi, Adamawa State, Nigeria

Environmental factors such as relative humidity and rainfall generally have been found to increase the incidence, rate of spread and severity of diseases thereby reducing yield of crops. Study was conducted on five cotton varieties, which were artificially inoculated with bacterial blight pathogen to determine the effects of rainfall and relative humidity on incidence and severity of angular leaf spot (ALS) and yield of seed cotton in Yola and Mubi. Results showed that the severity of ALS was higher in Yola (58.65%) at 13 WAS assumed to be due to higher relative humidity range of 76% - 87% and low rainfall of 2 - 40.6 mm. This is assumed to have favoured disease development as against that of Mubi location which recorded lower severity (51.11%) due to lower relative humidity (42% - 55%) and rainfall (37 - 73 mm). Results further revealed that at 13 WAS, SAMCOT-8 had low incidence (66%) and severity (39%) in Yola. This was against the much higher corresponding incidence and severity of 82% and 42% respectively that was observed in Mubi during the same period. SAMCOT-10 and SAMCOT-9 varieties were found to be highly susceptible to the disease at the same period. SAMCOT-8 recorded the highest yield of 390.00 kg?ha?1 in Yola and 868.09 kg?ha?1 in Mubi while the lowest yields of 227.17 kg?ha?1 was observed on SAMCOT-10 in Yola while 461.61 kg?ha?1 was obtained on SAMCOT-9 in Mubi. The variation in yield among these varieties might be due to the differences in their reactions to the disease. There is a need to conduct further trials in these locations to confirm the level of resistance or other aspects of these varieties to the disease

Effects of botanical extracts and antibiotic on incidence and severity of bacterial blight of cotton incited by Xanthomonas axonopodis pv. Malvacearum

A multilocational field trial was conducted to investigate the effect of some plant extracts (Bolanite aegyptica, Eucalyptus camaldulensis and Citrus aurantium) and a synthetic antibiotic (Streptomycin) on the incidence and severity of angular leaf spot on five cotton genotypes namely SAMCOT-8, SAMCOT-9, SAMCOT-10, SAMCOT-11 and SAMCOT-12 in Yola and Jalingo, both located in the northern guinea savannah zone of Nigeria. The experiment was carried out on a split-plot design having three replications with cotton genotypes on the main plots and plant extracts on the sub-plots. Data collected on the incidence and severity of the disease were analysed using the Generalized Linear Model procedure and means separation at 5% level of probability by Duncan Multiple Range Test. Findings of the study revealed that Streptomycin and Bolanite aegyptiaca were able to reduce the disease incidence by 18.12% from 58.69% in Yola at 13 WAS. In Jalingo however, B. aegyptiaca was found to have reduced the disease severity from 52.12% to 19.69% at 13 WAS. SAMCOT-8 consistently recorded lower incidence and severity means in Yola and Jalingo of 47.96%; 59.12% and 40.82%; 39.70% while SAMCOT-12 recorded higher means of 53.29%; 59.82% and 48.03%; 46.70% respectively