Improved maize growth in condition controlled by PGPR inoculation on ferruginous soil in central Benin

Abstract The use of microbial technologies in agriculture is rapidly expanding with the discovery of new bacterial strains effective in improving plant growth. In this study, we tested and highlighted the efficacy of PGPR (Plant Growth Promoting Rhizobacteria) alone or in a consortium on maize growth. For this purpose, a greenhouse experiment was carried out in pots containing sterilized ferruginous soil for 30 days. The corn seeds of the EVDT 97 SRT C1 variety were inoculated with bacterial suspensions of concentration 108 UFC/ml. The experimental device was a random block of 16 three-repeat treatments. The incidence of PGPR inoculated strains is assessed on the biomass growth and yield parameters of maize. At the end of the trial, the results showed that inoculation stimulated plant growth and development and resulted in a significant increase in the height, diameter at the collar, leaf surface and dry weight of aerial biomass. 20.15%, 21%, 32.77% and 37.73% respectively compared to controls, especially in corn plants inoculated with B. thurengiensis;B.thurengiensis B.panthethonicus- S.marcescens et Pseudomonas cichorii- Pseudomonas. putida- Pseudomonas syringae. These results show the potential of using these rhizobacteria as biological inoculants to improve maize productivity in Benin.

Influence of Isolated PGPR Rhizobacteria in Central and Northern Benin on Maize Germination and Greenhouse Growth

The objective of the study was to evaluate the effects of nine plant growth-promoting rhizobacteria (PGPR) alone or in combination on maize seed germination and seedling growth under laboratory and greenhouse conditions. The germination and growth tests were carried out in square petri dishes and pots. Maize seeds were inoculated with suspension of 108 CFU/ml of rhizobacteria. The experimental device was a random block of 16 treatments with four repetitions. Germination test results showed that seeds inoculated with PGPR including the control induced good germination in the range of 93.75% to 100%. The vigor index and root length of the seeds treated with Bacillus panthothenicus were significantly improved by 76.64% and 58.86%, respectively, while the maximal lengths of the seedlings were obtained with Pseudomonas cichorii with an increase of 118.95%. In greenhouse experience, data demonstrated that Serratia marcescens better improved the leaf area, height and underground biomass, respectively by 58.83%, 108.43%, and 59.16% as compared to the control. The highest fresh aerial biomass and air dry matter was obtained with plants treated only with Pseudomonas putida. These results show the potential to use such rhizobacteria as biofertilizers to improve maize productivity in Benin.

Tomato Hybrid and Local Varieties Screened for Resistance to Bacterial Wilt Caused by <i>Ralstonia solanacearum</i>under Screen House and Field Conditions

Bacterial wilt is the most damaging disease of tomato in Benin. To select resistant varieties of tomato against bacterial wilt, 21 tomato varieties were evaluated twice under screen house and field conditions in a randomized complete block design with four replicates and 21 treatments which are the tested varieties. Three weeks old tomato seedlings were inoculated by crown flooding with 40 ml of a bacterial suspension of R. solanacearum strain CR-1103-2, phylotype I sequvar 14. At 28 days after inoculation, the control resistant varieties Hawaii 7997 and PADMA maintained their resistance and the known susceptible variety Tohounvi showed to be susceptible to the bacterial wilt. Among the hybrid tomato varieties, only Cobra 26 was moderately resistant. No resistant line was found among the tested local varieties. The hybrid varieties Buffalo, Petomech, Tropimech, Sumo, Prado, Ninja, Jaguar, Anaya, Topaze, Cobra 34, Heinz, Kiara, Euclid and local Kêkêfo, Akikonkouin, Agbotrui and Adjaa were all susceptible. In conclusion, Cobra 26 emerges as a new variety of tomato moderately resistant to bacterial wilt. This is a new finding since it adds. All the tested varieties, regardless of their resistance, were colonized by R. solanacearum. This is a challenge for tomato farmers who must practice sanitation in their fields when producing tomato susceptible or resistant varieties. The variety Cobra 26 must be scaled up to farmers.

Applying Rhizobacteria on Maize Cultivation in Northern Benin:Effect on Growth and Yield

The aim of the study was to investigate the effects of five plant growth-promoting rhizobacteria (PGPR) (Bacillus panthothenicus;Pseudomonas Cichorii;Pseudomonas Putida;Pseudomonas syringae and Serratia marcescens) on the growth and yield of maize on a ferruginous soil under field condition. Maize seeds were inoculated with 10 ml of bacterial suspension. Study was conducted in a completely randomized design with fifteen treatments and three replicates. A half-dose of recommended (13, 17, 17 kg?ha?1) NPK was applied 15 days after emergence. The results show that the Serratia marcescens + 50% NPK treatment yielded the best results for height, fresh underground biomass, dry aboveground biomass, dry underground biomass, and grain yield with respective increases of 41.09%, 217.5%, 213.34%, 93.82%, and 39.05% compared to the control. Maximum stem diameter (increases of 49.65%) was recorded in the plants treated with 100% NPK (full dose NPK) while the highest leaf area (466.36 ± 9.57 cm2), obtained on plant treated with Pseudomonas putida + 50% NPK was 32.08% greater than in the non-inoculated control. Our results suggest the use of these rhizobacteria as biological fertilizers for enhancing the growth and maize seed yield in ferruginous soil in the North of Benin.

Physical and Technological Parameters of Maize Varieties (Zea mays L.) Grown in the Southern Parts of Benin and the Influence of Chemical Composition

Objective: The study aims to investigate some physical and technological parameters of varieties of maize collected from the most representative areas of maize production in the southern part of Benin, and mainly used by the populations of those areas. Method: The chemical composition, physical and technological characteristics of the grains were determined using standard methods. Results: The results showed that the weight of 1000 grains ranges from 158.01 to 305.12 g, the length from 0.79 to 1.81 cm, the average width from 0.74 to 1.51 cm, thickness from 0.36 to 0.85 cm and density from 1.07 to 1.25. Regarding the technological parameters, the hardness of the grains before and after cooking was between 16.78 and 47.20 kgf, and 0.23 and 0.71 kgf respectively, while the cooking time varies from 71.00 and 158.33 mn. There was a positive and significant correlation (r = 0.405;p < 0.026) between the hardness after cooking and the weight of 1000 grains, between the hardness after cooking and grain width (r = 0.460;p < 0.011). A positive and highly significant correlation (r = 0.527, p < 0.003) was also observed between the hardness after cooking and the grain length, between the hardness after cooking and the thickness of grain (r = 0.476, p < 0.008), and between the grain density and the weight of 1000 grains (r = 0.481, p < 0.007). A positive and highly significant correlation (r = 0.923, p < 0.000) was also observed between maize grain length and width, and between grain length and grain thickness (r = 0.764, p < 0.000) and between the width and thickness (r = 0.764, p < 0.000). On the other hand, a significant negative correlation (r = -0.394, p < 0.031) was found between the hardness before cooking and the thickness and between the hardness before cooking and sphericity index (r = -0465*, p Conclusion: Through its chemical and technological characteristics the maize constitutes an important raw material for many culinary recipes in West African region.

Effect of Different Plant Growth Promoting Rhizobacteria on Maize Seed Germination and Seedling Development

Our study aimed at assessing the effects of 3 Plants Growth Promoting Rhizobacteria (PGPR) either singly or in combination on maize growth under laboratory and greenhouse conditions. Seeds were inoculated with single and combined solution of 108 CFU/ml of Rhizobacteria. Seeds were not inoculated for the control variant. The highest germination percentage was obtained with the combination of Pseudomonas fluorescens and Pseudomonas putida. This combination also recorded the best vigor index, plants circumferences number of leaves and the leaf area. The maximal heights of plants were observed with seeds treated with Azospirillum lipoferum with an increase of 37.32%. The highest rates of underground dry matter were recorded with A. lipoferum, with an increase of more than 56% comparative to control, while the combination P. fluorescens and P. putida increased the aerial dry matter of 59.11%. Finally, the highest value of the aerial biomass was obtained with the plants treated with the combination of P. fluorescens and P. putida and the highest underground biomass was obtained with plants treated only with A. lipoferum. These results suggest that specific combinations of PGPR can be considered as efficient alternative biofertilizers to promote maize seed germination, biomass and crop yield.