Leafhoppers (jassids) are well-known pests of vegetable crops in Niger. They are often part of a parasitic complex that causes varying degrees of damage. Over the last two crop years, the Niamey region has seen a heav...Leafhoppers (jassids) are well-known pests of vegetable crops in Niger. They are often part of a parasitic complex that causes varying degrees of damage. Over the last two crop years, the Niamey region has seen a heavy outbreak of leaf hoppers on okra and guinea sorrel. These insects alone have caused spectacular damage, resulting in losses ranging from 50% to 100% of unharvested plants. Following this observation, infested fields were surveyed, specimens sampled, and the responsible species identified. Two sites were surveyed in the city of Niamey. At each site, two plots of okra and two of guinea sorrel were visited. Fifty (50) plants were randomly sampled using the double “W” method per plot. The sampled plants were used for active and passive leaf hopper capture, damage description and loss assessment. Captured leaf hoppers were identified based on their morphology observed with a binocular magnifying glass and compared with the data in the identification keys. The symptoms observed in the plots were yellowing, leaf curling and drying, stunting, abortion of flowers and immature fruit and very low production. Identification results revealed the single species Amrasca biguttula (Ishida, 1913), which can be considered a new invasive species in Niger. Further confirmation of this identification by molecular tests, the distribution of the pest in Niger and the development of appropriate control methods would yield good prospects.展开更多
Amaranth is one of the most consumed vegetables in Niger Republic because of its nutritional values. However, the production of this plant requires nutrient-rich soils that are becoming scarce in most agricultural soi...Amaranth is one of the most consumed vegetables in Niger Republic because of its nutritional values. However, the production of this plant requires nutrient-rich soils that are becoming scarce in most agricultural soils in Niger. This study aims to evaluate the fertilizing potential of the maggot production residue of Musca domestica L. 1758 and bovine excrement on the agronomic parameters of Amaranthus cruentus L., 1759. To do this, four densities (50, 100, 150, 200 g) of maggot production residue and bovine excrement were tested. Stem length, neck diameter and leaf number were strongly influenced by the interaction of the type of treatment (maggot production residue and bovine excrement) and dose. Dose 50 and dose 150 gave the best performance in length and diameter respectively for residue (length = 42.24 ± 8.98 cm;diameter = 0.88 ± 0.17 cm) and bovine droppings (length = 39.29 ± 8.10;diameter = 0.98 ± 0.77). On the leaf number side, no significant differences were observed between the doses for the residue. For bovine excrement, this number was higher at the 150 g dose (28.12 ± 4.98). The effect of the residue and bovine excrement on each corresponding dose shows that, for the stem length, only the 50 g dose was statistically influenced by the latter (P < 0.001). On the neck diameter side, only the 50 g and 100 g doses were statistically influenced by bovine residue and excrement (dose 50 g: P < 0.001;dose 100 g: P < 0.001). For each of these doses, the residue recorded the best performance both for the length of the rod and for the diameter at the collar. On the leaf number side, only the dose 50 g and 150 g varied statistically according to the type of fertilizer. At the 50 g dose, the residue recorded the largest number of leaves (27.10 ± 11.15), but the residue recorded the lowest number of leaves at the 100 g dose (21.01 ± 5.99). Foliar and root biomass varied statistically according to the dose within each fertilizer (foliar biomass: residue: P = 0.040;bovine excrement: P < 0.001;root biomass: residue: P < 0.001;bovine excrement: P < 0.001). The highest leaf biomass was obtained with doses 50 and 150 respectively for residue (155.00 ± 33.91 g) and bovine excrement (123.20 ± 20.57 g). The 150 g dose gave the best root biomass performance for the residue. For bovine excrement, the dose of 150 g and 200 g gave (without any significant difference between them) the best performance in root biomass with 21.80 ± 5.48 g and 21.50 ± 4.74 g respectively. The effect of residue and bovine excrement on each corresponding dose shows that, for foliar biomass, dose 50 and 100 g were statistically influenced by the latter (dose 50: P < 0.001;dose 100: P < 0.001). At each of these doses, the residue recorded the highest leaf biomass. For root biomass, each dose was statistically influenced by the type of fertilizer except dose 200 (P = 0.616). For each of these doses, maggot production residue gave better root biomass performance than bovine excrement except for dose 200 where no difference between the two fertilizers was observed (residue = 20.50 ± 3.97 g and dung = 21.50 ± 4.74 g). It appeared from this that the 50 g dose was to be the optimal dose of maggot production residue to bring for a better growth of amaranth plants. Whereas, this optimal dose is 150 g for the bovine droppings used in the present study.展开更多
文摘Leafhoppers (jassids) are well-known pests of vegetable crops in Niger. They are often part of a parasitic complex that causes varying degrees of damage. Over the last two crop years, the Niamey region has seen a heavy outbreak of leaf hoppers on okra and guinea sorrel. These insects alone have caused spectacular damage, resulting in losses ranging from 50% to 100% of unharvested plants. Following this observation, infested fields were surveyed, specimens sampled, and the responsible species identified. Two sites were surveyed in the city of Niamey. At each site, two plots of okra and two of guinea sorrel were visited. Fifty (50) plants were randomly sampled using the double “W” method per plot. The sampled plants were used for active and passive leaf hopper capture, damage description and loss assessment. Captured leaf hoppers were identified based on their morphology observed with a binocular magnifying glass and compared with the data in the identification keys. The symptoms observed in the plots were yellowing, leaf curling and drying, stunting, abortion of flowers and immature fruit and very low production. Identification results revealed the single species Amrasca biguttula (Ishida, 1913), which can be considered a new invasive species in Niger. Further confirmation of this identification by molecular tests, the distribution of the pest in Niger and the development of appropriate control methods would yield good prospects.
文摘Amaranth is one of the most consumed vegetables in Niger Republic because of its nutritional values. However, the production of this plant requires nutrient-rich soils that are becoming scarce in most agricultural soils in Niger. This study aims to evaluate the fertilizing potential of the maggot production residue of Musca domestica L. 1758 and bovine excrement on the agronomic parameters of Amaranthus cruentus L., 1759. To do this, four densities (50, 100, 150, 200 g) of maggot production residue and bovine excrement were tested. Stem length, neck diameter and leaf number were strongly influenced by the interaction of the type of treatment (maggot production residue and bovine excrement) and dose. Dose 50 and dose 150 gave the best performance in length and diameter respectively for residue (length = 42.24 ± 8.98 cm;diameter = 0.88 ± 0.17 cm) and bovine droppings (length = 39.29 ± 8.10;diameter = 0.98 ± 0.77). On the leaf number side, no significant differences were observed between the doses for the residue. For bovine excrement, this number was higher at the 150 g dose (28.12 ± 4.98). The effect of the residue and bovine excrement on each corresponding dose shows that, for the stem length, only the 50 g dose was statistically influenced by the latter (P < 0.001). On the neck diameter side, only the 50 g and 100 g doses were statistically influenced by bovine residue and excrement (dose 50 g: P < 0.001;dose 100 g: P < 0.001). For each of these doses, the residue recorded the best performance both for the length of the rod and for the diameter at the collar. On the leaf number side, only the dose 50 g and 150 g varied statistically according to the type of fertilizer. At the 50 g dose, the residue recorded the largest number of leaves (27.10 ± 11.15), but the residue recorded the lowest number of leaves at the 100 g dose (21.01 ± 5.99). Foliar and root biomass varied statistically according to the dose within each fertilizer (foliar biomass: residue: P = 0.040;bovine excrement: P < 0.001;root biomass: residue: P < 0.001;bovine excrement: P < 0.001). The highest leaf biomass was obtained with doses 50 and 150 respectively for residue (155.00 ± 33.91 g) and bovine excrement (123.20 ± 20.57 g). The 150 g dose gave the best root biomass performance for the residue. For bovine excrement, the dose of 150 g and 200 g gave (without any significant difference between them) the best performance in root biomass with 21.80 ± 5.48 g and 21.50 ± 4.74 g respectively. The effect of residue and bovine excrement on each corresponding dose shows that, for foliar biomass, dose 50 and 100 g were statistically influenced by the latter (dose 50: P < 0.001;dose 100: P < 0.001). At each of these doses, the residue recorded the highest leaf biomass. For root biomass, each dose was statistically influenced by the type of fertilizer except dose 200 (P = 0.616). For each of these doses, maggot production residue gave better root biomass performance than bovine excrement except for dose 200 where no difference between the two fertilizers was observed (residue = 20.50 ± 3.97 g and dung = 21.50 ± 4.74 g). It appeared from this that the 50 g dose was to be the optimal dose of maggot production residue to bring for a better growth of amaranth plants. Whereas, this optimal dose is 150 g for the bovine droppings used in the present study.
