Open Access Original Research Article

Yield Losses and Path Coefficient Analysis of Head Smut Disease (Tolyposporium penicillariae) in Pearl Millet Genotypes

Jeptanui Lilian, Kimurto Paul, Otaye Daniel, Mary Mgonja, Towett Bernard, Lagat Nicholas, Ojulong Henry

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/AJEA/2016/22981

Head smut caused by Tolyposporium penicillariae Bref. is a devastating fungal disease that cause up to 30% yield losses in pearl Millet (Pennisetum glaucum (L.) R.Br.). An experiment was carried out in two sites (Koibatek and Marigat) in Kenya to estimate the losses in grain yield due to head smut at varying levels of susceptibility in 50 promising advanced pearl millet genotypes. The test germplasm were planted in a complete randomized block design (RCBD) in three replicates during the short rains (Sept -Dec 2011) and long rains (April-July 2012). To assess the yield loss, two experiments were set as sprayed with fungicide to control disease and unsprayed. Results showed that among the tested genotypes, KAT PM1 and ICMV 221 were resistant checks and showed minimum yield loss as compared to the susceptible genotypes, (SDMV 94001 and SDMV 94014) which had highest yield loss. The mean grain yield loss varied between 6.5 and 60.8% in different genotypes. Both incidence and severity of the disease were significantly and positively correlated with losses in grain yield but severity contributed more. The prediction models for estimating yield losses were derived from yield in protected plots compared to none protected plots. Results showed that yield and disease severity were highly significant among the genotypes tested (Fpr <0.001) with yield ranging from 1172-4122 kg ha-1. Overall mean yield for both the seasons in the two sites was 2650 kgs ha-1for the sprayed experiment and 2390 kgs ha-1 in the diseased plots. The overall yield loss due to head smut was 18%. High yielding genotypes were SDMV 90031, IP 8783, SHIBE, ICMV 96603, ICMV221-1, IP6791 and ICMV 221 Bristled. These were recommended for further evaluation in multi-sites and be released as commercial varieties.

Open Access Original Research Article

Contribution of Legumes and Phosphorus Fertilizer to Nutrient Balances in a Sorghum Based Cropping System in Njoro Kenya

J. J. Lele, B. A. Tunya

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/AJEA/2016/26938

Aim: To determine nutrient balances in a sorghum based cropping system, following integration of legumes and phosphorus application.

Study Design: Two field experiments were set up. They comprised either white lupin or chickpea, and are subsequently referred to as lupin-sorghum and chickpea-sorghum, respectively. A split plot in a randomized complete block design was used. Main plots were cropping systems; sorghum monocrop, legume-sorghum rotation and legume/sorghum intercrop. Subplots were phosphorus sources; triple super phosphate and minjingu phosphate rock.

Place and Duration of Study: Njoro Kenya, in the short rains of 2012 and long rains of 2012 and 2013.

Methodology: N, P and K balances were determined using NUTrient MONitoring (now known as MonQi) Tool box.

Results: Nutrient balances were negative in both experiments, with nitrogen showing more negative values than phosphorus and potassium. Effect of cropping system and phosphorus sources on nutrient balances were significant (P = .05) in both experiments. Sorghum monocrop had more negative nitrogen and potassium balances, in both experiments. Phosphorus balance was more negative in the intercrop and monocrop in lupin-sorghum and chickpea-sorghum experiments, respectively. In the lupin-sorghum experiment, more negative nitrogen balance occurred with use of triple superphosphate in all cropping systems; for P with minjingu phosphate rock in intercropping and sole sorghum systems while for K, balances were more negative with minjingu phosphate rock in sorghum monocrop and intercrop. For the chickpea-sorghum experiment, N balance was more negative with the use of minjingu phosphate rock in the monocropping and intercropping system, for P, values were more negative with triple super phosphate in sorghum monocrop and intercropping systems while for K with triple superphosphate in all cropping systems.

Conclusion: Greater nutrient losses occurred in sole sorghum, hence unsustainable. Integration of white lupin or chickpea, in rotation and/or intercropping systems, with application of either phosphorus sources is recommended for enhanced sustainability of the system. An economic analysis of the farms is also recommended in future studies.

Open Access Original Research Article

Variability in Number of Seedling Potentials for Final Yield Evaluation in Rice (Oryza sativa L.)

O. S. Osekita, R. I. Adedoyin, B. O. Akinyele, O. A. Obembe, A. C. Odiyi, M. G. Akinwale

Journal of Experimental Agriculture International, Page 1-9
DOI: 10.9734/AJEA/2016/22537

Five lowland rice genotypes obtained from International Institute of Tropical Agriculture (IITA) Ibadan were grown during the rainy season of 2013/2014 to study factor analysis for yield and its components in rice (Oryza sativa L). The factors are the genotypes and numbers of seedlings planted per hill, the varieties were evaluated in a split plot design replicated three times, and the numbers of seedlings per hill were allotted to the subplot and the rice genotypes in the main plot. The study was conducted on the field of Akungba Akoko Plant Science and Biotechnology Department, Adekunle Ajasin University, Nigeria. The characters measured include: number of tillers/hill at 30 and 50 days after transplanting, plant height at 30 and 50 days after transplanting, final plant height, flag leaf length, number of effective tillers, number of spikelets per panicle, number of grain per panicle, grain length, grain width, panicle length, panicle weight, 1000 grain weight, and grain yield per hill. The results showed that there were no significant differences between the treatments and the genotypes and that the treatments have no effect on the yield of the genotypes. The PCV was higher than GCV for all characters in most cases.

Open Access Original Research Article

Status and Production Practices of Vegetable African Nightshade (Solanum nigrum L.) in Selected Communities of Kenya

Cecilia Moraa Onyango, Edward Gizemba Ontita, Richard Ndemo Onwong’a, Nyamongo Desterio, Jean R. Gapusi

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/AJEA/2016/27363

Aims: In order to improve production, utilization and conservation of African nightshades (ANS) in Kenya, this study set out to better understand the current status and agronomic practices employed by some of the Kenyan communities.

Study Design: The study entailed a survey of African nightshade farmers.

Place and Duration of Study: The study was carried out in representative counties, Kisii, Kakamega and Nakuru, of Kenya between the months of October and November, 2015.

Methodology: A total of 630 ANS farmers (210 farmers per county) randomly sampled from purposively selected sub-counties in each of the three counties were used. The farmers interviewed consisted of men, women and youth. In addition, 6 focus group discussions consisting of 15 participants per group and 9 key informant interviews were conducted in each county to provide detailed information and opinion on the data collected during the survey. Data was collected on characteristics of Solanum farmers, agronomic practices in ANS production, amount of land allocated to ANS, income from ANS sales and challenges encountered in ANS production.

Results: Results indicated that 75-80% of the ANS growers were women and 63% of farmers in Kakamega had primary education while 56% in Kisii and 40% in Nakuru of the farmers had high school education. Production is in small holdings (<0.25 acres), 71%-80% of all farmers used hand hoes while planting methods differed among the communities with hill planting being dominant in Kakamega (70%) and broadcasting common in Nakuru (42%). Further >50% of the farmers mainly applied wood ash for pest and disease control while 73% used animal manure for plant nutrition. The farmers identified pests and diseases as the main challenge encountered during ANS production. 

Conclusion: ANS production is mainly a women activity with formal education up to secondary school level. More land is being allocated for ANS production. However, the production is still on small scale using rudimentary tools and farmers employ traditional methods to control pests and diseases. Moreover, pests and diseases is the main limitation to increased production of ANS.

Open Access Original Research Article

Studies on Heterosis for Summer Season Tomato Production

A. Biswas, M. S. Islam, S. Dey, A. A. Shimu

Journal of Experimental Agriculture International, Page 1-6
DOI: 10.9734/AJEA/2016/26402

An investigation was carried out with a view to estimating heterosis for yield and its attributes under high temperature conditions at the experimental field of Horticulture, Department of Agriculture, Sylhet Agricultural University, Bangladesh during hot summer season (May to August) of 2013. In this study  ten tomato hybrids developed from half diallel crossing fashion among five parental lines of tomato in winter season of 2012- 2013 (October 2012 to February 2013). These ten tomato hybrids along with five parental lines were evaluated under RCB design with three replications to estimate better parent heterosis for ten characters. Significant better parent heterosis was found for all characters except days to first harvest. The maximum better parent heterosis for number of fruits per plant was observed for the cross combination of C51 × C71 (85.12%) followed by C41 × C11 (67.10%). The highest heterosis for individual fruit weight was recorded (69.31%) from FP5 × C71 indicating this combination is important for improvement of individual fruit weight of heat tolerant tomato. The highest positive significant heterosis for pericarp thickness was found for the cross combination of C41 × C71 (60%) followed by C11 × C71 (46.25%). Positive and significant heterosis for TSS (%) was estimated from the cross C11 × FP5 (8.7%). All the cross combinations showed positive and significant heterobeltiotic effect for fruit yield per plant of which C41 × FP5 exhibited the highest heterosis (203.22%) closely followed by  C41 × C51 (183.33%). Therefore, this two cross combinations can be taken for further evaluation under high temperature condition for recommending summer season cultivation in Bangladesh.

Open Access Original Research Article

Evaluation of Potency and Efficacy of Commercial Brands of Newcastle Disease Vaccines in Nigeria

I. O. Olatoye, D. O. Oluwayelu, J. Y. Adeseko, I. A. Adebiy, S. O. Adeyemi

Journal of Experimental Agriculture International, Page 1-6
DOI: 10.9734/jeai/2016/v13i31889

Aims: To evaluate the potency and efficacy of four commercially available brands of Newcastle disease (ND) vaccines in southwest Nigeria.

Study Design: Cross sectional survey of commercial ND (Hitchner and LaSota) for in-vitro and in-vivo analysis.

Place and Duration of Study: Vaccines were obtained from manufacturers’ representatives in southwest Nigeria while chicks were obtained from commercial hatchery, reared at the Teaching and Research Farm and analysis was carried out at Department of Veterinary Microbiology in University of Ibadan. 

Methodology: Isa Brown cockerel chicks divided into five groups (A-E) comprising 60 birds each were used. Chicks in groups A-D were vaccinated primarily with four different brands (ND-Sevac®; ND-Jovac®, ND-Biovac® and ND-Fort Dodge®) of Hitchner B1 (HB1) vaccine at one-day-old (Day 1) and later with four corresponding brands of LaSota (booster) vaccine at day 21. Chicks in the fifth group which served as control received no vaccine and were used to assess the rate of maternal antibody decay. Sera were collected on days 1, 9, 16, 32, and 39 of age and the chickens were challenged with Kudu strain of ND virus (NDV) on day 33. Haemagglutination (HA) and haemagglutination inhibition (HI) tests were used to determine NDV titre and antibody levels in the vaccines and sera respectively.

Results: NDV maternal antibody level was highest (64±18.2) on day 1 and persisted to a minimum protective level (8±5.7) on day 16 before decaying to non-protective levels by day 32. All the four vaccine brands were potent with Biovac® (Vaccine C) yielding the highest NDV titres [HB1 (1536±724.1), LaSota (512±0.0)]. Also, following the administration of primary and booster (secondary) vaccinations, all the vaccines elicited protective immunity with the booster doses producing higher immune response in all the groups. However, chicks that received ND-Jovac® and ND-Biovac® were best able to overcome the effects of experimental challenge as they gave the lowest mortality rate of 33.3% with mean NDV antibody titres of 9 log2 (512±313.5) recorded seven days post-challenge. Chicks that received Sevac® and Fort Dodge®(Vaccines A and D) gave mortality rates of 55.0% and 50.0%, respectively with mean antibody titres of 7 log2 (154±57.3) post-challenge.

Conclusion: All the tested vaccines were potent and elicited protective antibody. However, ND outbreaks in vaccinated flocks in southwest Nigeria may not necessary be due to lack of potency of the vaccines but other factors such as virus strain (s) used in the production of the vaccines, vaccine storage and handling and biosecurity among others may play a role. Therefore, there is a need for routine isolation and characterization of the enzootic strain(s) of NDV in Nigeria and production of ND vaccines with such circulating strain(s) to offer optimal protection against the disease.

Open Access Original Research Article

Inclusion of Monosex Tilapia (Oreochromis niloticus) with Freshwater Prawn (Macrobrachium rosenbergii) in Polyculture Systems in the Ponds of Coastal Region: Impact of Stocking Density of Tilapia on Production and Profitability

M. S. Islam, Y. Mahmud, N. Begum

Journal of Experimental Agriculture International, Page 1-9
DOI: 10.9734/AJEA/2016/27463

Experiment was carried out to ascertain the impact of stocking density of monosex tilapia (Oreochromis niloticus) on production and profitability in freshwater prawn (Macrobrachium rosenbergii) farming system over a period of 150 days at farmers’ shrimp ponds, Madrasha village, Bamorta union, Bagerhat district. There were three treatments viz. T1, T2 and T3 with tilapia of 10,000, 15,000 and 20,000/ha, respectively and each having three replicates. Density of prawn at 20,000/ha was maintained in all the treatments. Ponds were stocked with monosex tilapia and all male prawn juvenile. On average, 25 genera of phytoplankton and 6 genera of zooplankton were identified from pond water. Water quality parameters were within suitable ranges for tilapia and prawn in all the treatments. Mean weight of tilapia decreased significantly (p<0.05) with increasing stocking density but survival rate did not differ significantly. Higher production of prawn was obtained in T1 (950.4 kg/ha) followed by T2 (923.0 kg/ha) and T3 (805.2 kg/ha). On the contrary, production of tilapia was significantly higher in T3 (1,686.60 kg/ha) and T2 (1,587.60 kg/ha) than in T1 (1,310.0 kg/ha). However, the overall total production of tilapia and prawn was significantly (p<0.05) higher in T2(2,510.60 kg/ha) and T3 (2,491.80 kg/ha) compared to T1 (2,260.40 kg/ha). Higher profit was also found in T2(BDT 238,923.00/ha) followed by T(BDT 222,557.00/ha) and T3 (147,819.00/ha). Therefore, the results of the study implied that inclusion of tilapia at a density at 15,000/ha enhanced the total production and contributed greatly to earn higher profit.