The cultivation of fruit trees generally requires a nursery phase during which the young seedlings are monitored and treated to improve their ability to adapt to the environment. This leads to the production of seedli...The cultivation of fruit trees generally requires a nursery phase during which the young seedlings are monitored and treated to improve their ability to adapt to the environment. This leads to the production of seedlings that are used to create orchards. It consists of four essential steps or operations: 1) The germination phase of the seeds in germinators for the production of rootstocks;2) Transplanting into pots or bags;3) Fertilisation in order to obtain seedlings of a satisfactory vigour (stem diameter) ready for grafting. The nursery phase requires a good understanding and mastery of plant regeneration and fertilisation techniques. In Cameroon, the demand for avocado (Persea americana) fruits is increasing, but the supply is not keeping up with this demand. After a summary monograph on the production practices of avocado seedlings in the Yaounde area, this work aims to optimise the aforementioned three steps in order to obtain seedlings of sufficient sizes for grafting. Three factors are considered in this study: 1) The substrate (Substrate), whose effects are evaluated by the germination rate (GR), the daily average germination (DAG) and the root volume of seedlings (RootV). 2) The transplanting date (TransD), determined by considering three dates including 40 (Trans40), 65 (Trans65) and 75 (Trans75) days after sowing, and 3) Fertilisation using biological fertilisers, evaluated by testing four fertilisation levels, Fert1 (10 gr of 20-10-10 plus 10 gr fowl droppings), Fert2 (Acaulospora tuberculata), Fert3 (Gigaspora margarita) and Fert4 (Mixed mycorrhizal strains of Gigaspora margarita and Acaulospora tuberculata). This third factor is evaluated by growth parameters including leaf area (LeafA), chlorophyll index (ChlorInd), gain in Plant height (GainPltH) and plant diameter (GainPltD). The trial took place in the First Seed company, a seed production unit located in the Simbock district of Yaounde for the field phase, and the Biological Control Laboratory of the Institute of Agricultural Research for Deve展开更多
The popularization of <i>Dioscorea dumetorum</i> (Dioscoreaceae), a nutritious yam species is still marginal due to constraints such as the low interest of research, poor cultural practices, insufficient a...The popularization of <i>Dioscorea dumetorum</i> (Dioscoreaceae), a nutritious yam species is still marginal due to constraints such as the low interest of research, poor cultural practices, insufficient and expensive seeds, pests, and diseases. The latter pushes producers to use about 50% of their harvest as seed for the next planting season. The lack of a specific fertilizer formulation for yam production on the oxysols of Cameroon is another constraint. This study was aimed at enhancing the availability of quality seeds through the characterization of five yam accessions. One experiment was performed to determine the effect of cultivar and origin of tuber sets on their germination rate. The <span>second concerned the evaluation of cultivars and soil treatment effects on ag</span>ronomic parameters of yam seedlings. Yam cultivars were subjected to nine fertilizer formulations as follows: T0: no fertilizer;T1: mycorrhizal fungi (MF) + 150 g manure + peanut waste;T2: 25 g chemical fertilizer (20.10.10);T3: MF + peanut waste;T4: 16 g chemical fertilizer (12.6.20);T5: 25 g (20.10.10) +100 g CaO + 150 g manure;T6: 100 g CaO + 150 g manure;T7: 20 g tropicote + 2 g DAP (Diammonium phosphate, a reference starter fertilizer coded N18P46) + 100 g CaO + 150 g manure;and T8: mycorrhiza. These treatments were tested in a factorial design. Results show that Ibo sweet 3 and Mabondji sweet white 1 yam accessions were less affected by anthracnose disease on the aerial parts. Guzang 1 showed the best germination rate and yield, making it appropriate for cultivation in the region. Soil treatments, T2, T5, T7 and T8 significantly increased the yield of yam cultivars. Mycorrhiza treatment alone gave a better response to seed weight, indicating the interest of this biofertilizer as a solution for good seedling production. These fertilizer treatments can be recommended to farmers for more seed production with optimum seed weight (300 g).展开更多
The Rio Grande variety of tomato is widely grown because of its high productivity during the cold and dry seasons, and its resistance to Verticillium wilt (caused by Fusarium oxysporium) and to stem canker (Alternaria...The Rio Grande variety of tomato is widely grown because of its high productivity during the cold and dry seasons, and its resistance to Verticillium wilt (caused by Fusarium oxysporium) and to stem canker (Alternaria). Grafting tomato onto compatible rootstocks resistant to these diseases offers a better potential to overcome soil-borne diseases, abiotic stresses, improve growth, yield and fruit quality. However, in Cameroon, there is little or no information on grafting between Rio Grande tomato and selected eggplant rootstocks. The objectives of this study were: 1) To determine the compatibility between Rio tomato grafting and a popular local eggplant (Nkeya) rootstock;2) To verify the effect of grafting on flowering time;3) To evaluate the effect of eggplant rootstocks on growth, fruit shelf life and fruit quality of Rio tomatoes. The trial was conducted in a randomized complete block design with 3 replications. Rio Grande (To) was the ungrafted treatment used as a control. To/Ko, To/To and To/Nk were the grafted treatments eventually transplanted to the field. Growth data were subjected to analysis of variance using SPSS software. Descriptive analyses were performed for the other parameters. The results revealed that, 1) The cleft grafting method used was successful with success rate varying between 90 and 100%;2) Grafting influenced flowering date (DAT, p = 0.05) as well as tomato growth parameters including stem height (H, 1.49 × 10<sup>-10</sup> p 0.00014) and collar diameter (SD, 4 × 10<sup>-1</sup><sup>4</sup> p 0.009). The To/To treatment was significantly different from the ungrafted cultivar To, which had no significant difference in stem diameter. A significant difference in plant height was also observed between the ungrafted treatment To and the To/Ko and To/Nk treatments. In addition, only the collar diameter of To/Nk was different from To. Also, there was no significant difference between To/To and To, but a significant difference between To/Ko and To/Nk compared to To. Conversely, grafting im展开更多
文摘The cultivation of fruit trees generally requires a nursery phase during which the young seedlings are monitored and treated to improve their ability to adapt to the environment. This leads to the production of seedlings that are used to create orchards. It consists of four essential steps or operations: 1) The germination phase of the seeds in germinators for the production of rootstocks;2) Transplanting into pots or bags;3) Fertilisation in order to obtain seedlings of a satisfactory vigour (stem diameter) ready for grafting. The nursery phase requires a good understanding and mastery of plant regeneration and fertilisation techniques. In Cameroon, the demand for avocado (Persea americana) fruits is increasing, but the supply is not keeping up with this demand. After a summary monograph on the production practices of avocado seedlings in the Yaounde area, this work aims to optimise the aforementioned three steps in order to obtain seedlings of sufficient sizes for grafting. Three factors are considered in this study: 1) The substrate (Substrate), whose effects are evaluated by the germination rate (GR), the daily average germination (DAG) and the root volume of seedlings (RootV). 2) The transplanting date (TransD), determined by considering three dates including 40 (Trans40), 65 (Trans65) and 75 (Trans75) days after sowing, and 3) Fertilisation using biological fertilisers, evaluated by testing four fertilisation levels, Fert1 (10 gr of 20-10-10 plus 10 gr fowl droppings), Fert2 (Acaulospora tuberculata), Fert3 (Gigaspora margarita) and Fert4 (Mixed mycorrhizal strains of Gigaspora margarita and Acaulospora tuberculata). This third factor is evaluated by growth parameters including leaf area (LeafA), chlorophyll index (ChlorInd), gain in Plant height (GainPltH) and plant diameter (GainPltD). The trial took place in the First Seed company, a seed production unit located in the Simbock district of Yaounde for the field phase, and the Biological Control Laboratory of the Institute of Agricultural Research for Deve
文摘The popularization of <i>Dioscorea dumetorum</i> (Dioscoreaceae), a nutritious yam species is still marginal due to constraints such as the low interest of research, poor cultural practices, insufficient and expensive seeds, pests, and diseases. The latter pushes producers to use about 50% of their harvest as seed for the next planting season. The lack of a specific fertilizer formulation for yam production on the oxysols of Cameroon is another constraint. This study was aimed at enhancing the availability of quality seeds through the characterization of five yam accessions. One experiment was performed to determine the effect of cultivar and origin of tuber sets on their germination rate. The <span>second concerned the evaluation of cultivars and soil treatment effects on ag</span>ronomic parameters of yam seedlings. Yam cultivars were subjected to nine fertilizer formulations as follows: T0: no fertilizer;T1: mycorrhizal fungi (MF) + 150 g manure + peanut waste;T2: 25 g chemical fertilizer (20.10.10);T3: MF + peanut waste;T4: 16 g chemical fertilizer (12.6.20);T5: 25 g (20.10.10) +100 g CaO + 150 g manure;T6: 100 g CaO + 150 g manure;T7: 20 g tropicote + 2 g DAP (Diammonium phosphate, a reference starter fertilizer coded N18P46) + 100 g CaO + 150 g manure;and T8: mycorrhiza. These treatments were tested in a factorial design. Results show that Ibo sweet 3 and Mabondji sweet white 1 yam accessions were less affected by anthracnose disease on the aerial parts. Guzang 1 showed the best germination rate and yield, making it appropriate for cultivation in the region. Soil treatments, T2, T5, T7 and T8 significantly increased the yield of yam cultivars. Mycorrhiza treatment alone gave a better response to seed weight, indicating the interest of this biofertilizer as a solution for good seedling production. These fertilizer treatments can be recommended to farmers for more seed production with optimum seed weight (300 g).
文摘The Rio Grande variety of tomato is widely grown because of its high productivity during the cold and dry seasons, and its resistance to Verticillium wilt (caused by Fusarium oxysporium) and to stem canker (Alternaria). Grafting tomato onto compatible rootstocks resistant to these diseases offers a better potential to overcome soil-borne diseases, abiotic stresses, improve growth, yield and fruit quality. However, in Cameroon, there is little or no information on grafting between Rio Grande tomato and selected eggplant rootstocks. The objectives of this study were: 1) To determine the compatibility between Rio tomato grafting and a popular local eggplant (Nkeya) rootstock;2) To verify the effect of grafting on flowering time;3) To evaluate the effect of eggplant rootstocks on growth, fruit shelf life and fruit quality of Rio tomatoes. The trial was conducted in a randomized complete block design with 3 replications. Rio Grande (To) was the ungrafted treatment used as a control. To/Ko, To/To and To/Nk were the grafted treatments eventually transplanted to the field. Growth data were subjected to analysis of variance using SPSS software. Descriptive analyses were performed for the other parameters. The results revealed that, 1) The cleft grafting method used was successful with success rate varying between 90 and 100%;2) Grafting influenced flowering date (DAT, p = 0.05) as well as tomato growth parameters including stem height (H, 1.49 × 10<sup>-10</sup> p 0.00014) and collar diameter (SD, 4 × 10<sup>-1</sup><sup>4</sup> p 0.009). The To/To treatment was significantly different from the ungrafted cultivar To, which had no significant difference in stem diameter. A significant difference in plant height was also observed between the ungrafted treatment To and the To/Ko and To/Nk treatments. In addition, only the collar diameter of To/Nk was different from To. Also, there was no significant difference between To/To and To, but a significant difference between To/Ko and To/Nk compared to To. Conversely, grafting im
