Open Access Original Research Article

Agronomic Potential of Some Rubber Tree Clones (Hevea brasiliensis) of the Fast Metabolic Activity Class in the Absence of Hormonal Stimulation in Southwestern of Côte d’Ivoire

G. J. O. Atsin, E. F. Soumahin, T. H. Kouakou, A. E. A. Elabo, K. M. Okoma, S. Obouayeba

Journal of Experimental Agriculture International, Page 1-13
DOI: 10.9734/AJEA/2016/26930

Fast-metabolism clones of rubber tree (Hevea brasiliensis) are appreciated for their good agronomic performance with little hormonal stimulation, due to their high intrinsic metabolic activity. They are highly demanded and therefore exposed to a significant risk of overexploitation. In order to solve this problem, a study was carried out in a completely randomized design with clones IRCA 111, IRCA 130 and PB 260 planted at a density of 510 plants/ha in southwestern of Côte d’Ivoire for nine years. A single tapping system, that is every four days (d4) with different hormonal stimulation regimes (0/y; 2/y; 4/y; 6/y; 8/y; 13/y; 18/y; 26/y and 39/y), was applied to all treatments. The parameters measured in rubber trees were rubber yield, radial vegetative growth, physiological profile and sensitivity to tapping panel dryness. The results indicated that non-stimulated rubber trees of clones IRCA 111 and IRCA 130 showed the best rubber yields while two annual stimulations were necessary for clone PB 260. Moreover, the lack of hormonal stimulation had no negative impact on the vegetative growth, physiological profile and sensitivity to tapping panel dryness of the rubber trees. Clones IRCA 111 and IRCA 130 can therefore be tapped in S/2 d4 without hormonal stimulation.

Open Access Original Research Article

Bioefficacy of Garlic, Allium sativum and Tobacco Nicotiana tabacum on Mortality, Ovipository Inhibition and Adult Emergence of the Cowpea Beetle Callosobruchus maculatus (Fab.) on Cowpea Vigna unguiculata (L.) (Walp.)

P. K. Baidoo, M. B. Mochiah

Journal of Experimental Agriculture International, Page 1-9
DOI: 10.9734//AJEA/2016/26081

Aims: To evaluate the efficacy of aqueous and ethanolic extracts of garlic and tobacco in the management of the cowpea beetle (Callosobruchus maculatus) and how these affect oviposition by adult females, adult emergence and sex ratio.

Study Design: The study was conducted in a randomised complete block design consisting of six treatments and three replications.

Place and Duration of Study: The experiment was carried out at the Biocontrol Section of Crops Research Institute, Kwadaso, Kumasi over a four month period.

Methodology: Aqueous and ethanolic extracts of garlic and tobacco leaves were prepared; these preparations were compared with a standard chemical insecticide, Betallic and a control. Four kilogrammes of untreated cowpea seeds were sorted to obtain whole uninfested grains. Six hundred of the sorted seeds were placed in 1L Kilner jars. Fifty millilitres of each extract was sprayed onto the seeds in their respective jars and allowed to dry. Ten pairs of adult C. maculatus were introduced into each jar. Similar set-ups were done with the insecticide and control seeds. Mortality was recorded every 6 hours after treatment for 24 hours. Data were also collected on oviposition, adult emergence and sex ratio.

Results: Garlic-treated seeds did not record any mortality within the first 18 hours; no mortality was recorded in the control seeds, whereas the insecticide-treated seeds recorded 100 % mortality. Significantly fewer eggs were laid on the treated seeds than the control seeds. Sex ratio of the emerged adults varied within the period of observation. Aqueous extracts of the botanicals performed better in terms of insect control and oviposition inhibition than the ethanolic extracts.

Conclusion: Aqueous extracts of both plants produced better results than the ethanolic extracts. Aqueous extract, being cheaper, easier and safer to prepare could be adopted by the average small-scale farmer to manage C. maculatus.

Open Access Original Research Article

Evaluation of Selected French Bean (Phaseolus vulgaris L.) Genotypes for Resistance to Angular Leaf Spot (Pseudocercospora griseola) in Western Kenya

S. K. Kimno, O. K. Kiplagat, E. E. Arunga, E. Chepkoech

Journal of Experimental Agriculture International, Page 1-6
DOI: 10.9734/AJEA/2016/26874

French bean, a sub-group of the common bean (Phaseolus vulgaris L.), is grown for its tender green pods. It is a major export crop in Kenya but production levels are constrained by both biotic and abiotic stresses. Angular leaf spot (ALS) disease, caused by Pseudocercospora griseola, can cause major reductions in yield. The pathogen is highly variable and endemic in various agro-ecological zones. Genetic resistance against ALS is a high breeding priority, as effective cultural control is difficult. The main objective of this study was to evaluate French bean germplasm for ALS resistance in western Kenya. A set of 26 commercial varieties, three breeding lines, three landraces and two checks (resistant and susceptible dry bean cultivars) were planted in a randomized complete block design with three replicates at three sites in Kenya (Eldoret, Kisii and Kakamega) in 2014. Disease assessment was done using a 1-9 CIAT scale. There were significant (P ≤ 0.05) differences in disease severity between the three sites: the Kakamega site experienced the greatest disease pressure (mean severity of 6.2), followed by the Kisii site (5.7) and the Eldoret site (5.3). Only one out of the 34 entries (not a French bean variety) showed field resistance to ALS. Most exhibited either an intermediate or a susceptible reaction at all three sites. The resistant control Mexico 54 (a dry bean variety) remained clear of ALS infection, so could represent a useful donor of resistance in a French bean breeding program. There remains a need to identify further donors of resistance, preferably within the French bean genepool.

Open Access Original Research Article

Challenges on Production and Utilization of White Lupin (Lupinus albus L.) in Ethiopia: A Strategic Orphan Crop

Hibstu Azeze, Firew Mekbib, Yigzaw Dessalegn, Zerihun Tadele, Negussie Megersa

Journal of Experimental Agriculture International, Page 1-14
DOI: 10.9734/AJEA/2016/27930

Aim: To assess the potentials and constraints of production and utilization of white lupin in the major growing areas and analyze the production, area coverage and productivity trend in Ethiopia.

Study Design: Purposive sampling method was used to select districts and random sampling procedure followed to select respondents among white lupin producers.

Methodology: Survey was conducted on Feb 2013 at Machakel and Banja districts of Eastern Gojjam and Awi Zones of Amhara Regional respectively. A sample size of 80 respondents for the two districts was used. The data was analyzed with SPSS 16.0 software, and descriptive statistics was used to interpret the results. In the trend analysis, three forecasting models such as linear trend model, quadratic trend model, and exponential growth model were used to find the best fitted model for area coverage, production, and productivity of white lupin. Forecasting errors namely mean absolute percentage error; mean absolute deviation and mean squared deviation were used as model selection criteria.

Results: The study areas showed significant difference (p<0.001) for production and utilization practices.

About 82.5% and 66.7% of the respondents at Banja and Machekel districts respectively replied on consumption of snack as supplementary food. Farmers produce the crop with minimum or no cultural practices. About (40%) respondents intercrop white lupin with other crops. Farmers use their own seeds; lack of production packages, late maturity, disease and stepwise postharvest processing are the major constraints. The quadratic model, due to its lowest values of the forecasting errors, was best fitted to predict the future estimate of area, production, and productivity of white lupin.

Conclusion: If the current production practices remain unchanged, decreasing in total area coverage, production and productivity will continue. Therefore, for better utilization of this potential crop, the current indigenous farmers’ practices need to be supported by research based technologies of production and utilization.

Open Access Original Research Article

Physiological and Technological Consequences of Benzyl Adenine (BAP) Application on Butternut Squash (Cucurbita moschata Duchesne ex Poir.) Productivity

P. Della Gaspera, J. Teruel, E. Giardina, A. Di Benedetto

Journal of Experimental Agriculture International, Page 1-11
DOI: 10.9734/AJEA/2016/27826

Some authors have indicated that the reason why benzyl adenine (BAP) stimulates dry matter accumulation in squash and pumpkin is unclear, but we believe that two possibilities are likely: (i) higher photo-assimilate partitioning towards the shoot; or (ii) increased in the photosynthetic efficiency of leaves. Thus, the aim of this work was to study the effect of an exogenous BAP spray on biomass accumulation and yield in pumpkin plants grown in commercial facilities. Our results showed that, the relative growth rate of Butternut squash plants grown under commercial plant density did not change and that yield was the same in both BAP-sprayed and control plants. However, a single BAP application decreased leaf size and total leaf area per plant but increased the rate of leaf appearance. Our findings suggest the possibility of an increase in plant populations through changes in crop architecture and an increase in yield on a field area basis.

Open Access Original Research Article

In vitro Sterilization of Alstroemeria hybrida cv. Pluto

Ambreena Din, Imtiyaz T. Nazki, Muneeb A. Wani, Sajid A. Malik, Shameen Iqbal

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/AJEA/2016/27020

The present study was designed to standardize protocol for asepsis of different explants of Alstroemeria hybrida cv. Pluto (rhizome tips, rhizome sections, shoot tips and shoot nodal segments). Carbendazim 200 ppm for 30 minutes + mercuric chloride (0.1%) dip for 10 minutes and final treatment with ethyl alcohol (70%) for one minute proved best for culture asepsis of rhizome tips and rhizome sections at 2 and 4 weeks of culture, whereas carbendazim 200 ppm for 15 minutes followed by mercuric chloride 0.1% dip for 3 minutes proved better for culture asepsis of shoot tip and shoot nodal segments at 2 and 4 weeks of culture. Also carbendazim 200 ppm for 30 minutes + mercuric chloride (0.1%) dip for 10 minutes and final treatment with ethyl alcohol (70%) for one minute proved best for culture survival of rhizome tips and rhizome sections at 4 weeks of culture., whereas carbendazim 200 ppm for 15 minutes followed by mercuric chloride 0.1% dip for 3 minutes proved better for culture survival of shoot tip and shoot nodal segments at 4 weeks of culture. In this study protocol for sterilization of different explants leads to the standardization of the explant for tissue culture in Alstroemeria hybrida cv. Pluto.

Open Access Original Research Article

Evolution of Ochratoxin A Contents during Storage of Cowpea (Vigna unguiculata L Walp) Bagged PICS with Lippia multiflora Moldenke Leaves and Estimation of Daily Intake in Adult Ivorian

Constant K. Konan, Adama Coulibaly, Sidibe Daouda, Olivier Chatigre, Henri Marius G. Biego

Journal of Experimental Agriculture International, Page 1-14
DOI: 10.9734/AJEA/2016/28164

Aims: This study aims to test the effectiveness of the cowpea conservation method in PICS (Purdue Improved Cowpea Storage) bags with a Lippia multifla leaves on the evolution of ochratoxin A and the estimated daily intake in adult Ivorian

Study Design: Cowpea grains that have undergone any treatment were collected between May and June 2015 in the southwest of Côte d’Ivoire. The fresh leaves of Lippia multiflora were collected and dried in sunlight for 7 days in the center of Cote d'Ivoire. The supply PICS bags were made in Abidjan. All this material was sent to the Laboratory of Biochemistry and Food Sciences, Félix Houphouët-Boigny University, Côte d’Ivoire, to perform the experiment. For the experimental realization, 6 conservation methods have been adopted. The first method was conservation of 50 kg of cowpea grain in a polypropylene bag. The second method was conservation of 50 kg of cowpeas in a PICS bag. The other four methods were carried out with PICS bags each containing 50 kg of cowpea grain and different proportions of chopped leaves Lippia multiflora (0.7%, 2.5%, 4.3% and 5% weight of leaves by weight of cowpea). Filling the bags was made by alternating the chopped leaves of Lippia multiflora and cowpea grains as stratum. The six types of packaging were stored on pallets in the warehouse laboratory reserved for this purpose.

Place and Duration of the Study: This study was carried out during June 2015 to February 2016 in the Laboratory of Biochemistry and Food Science, Félix Houphouët-Boigny University, Côte d’Ivoire

Methodology: A central composite design was used for sample constitution. Thus, a control group with polypropylene bags (TSP), a control group in PICS bags without Lippia multiflora (H0) and 4 experimental lots of PICS bags containing different proportions (0.7%, 2.5%, 4.3% and 5% (w / w)) Lippia multiflorarespectively noted H1, H2, H3 and H4, have been used. Changes in moisture, the water activity (Aw) and the levels of ochratoxin A (OTA) cowpea grains stored for 8 months were studied.

Results: The results reveal the presence of OTA in all samples analyzed. However, only 17.65% of the samples had higher levels of OTA than the reference values set by the European Union. PICS bags contain lower levels of OTA. These levels are even lower when the cowpea is stored in PICS bags containing different concentrations of leaves of Lippia multiflora. The estimated daily intake of OTA under the cowpea consumption stored for 8 months were respectively 0.58±0.06 ng / kg body weight/day, 0.66±0.03 ng / kg bw / day, 0.30±0.05 ng / kg body weight / day, 0.30±0.00 ng / kg body weight / day and 0.28±0.00 ng / kg body weight / day for H0, H1, H2, H3 and H4. These levels are below the maximum permissible reference value set by the WHO.

Conclusion: Storage of cowpeas in PICS bags with the leaves of Lippia multiflora appears as a method of effective and inexpensive conservation to ensure the health quality of cowpea.