Parasitic angiosperm Alectra vogelii Benth is a growing problem in Malawi, particularly with current emphasis on legumes. Therefore, two studies were set in order to understand the possible mechanisms of resistance in...Parasitic angiosperm Alectra vogelii Benth is a growing problem in Malawi, particularly with current emphasis on legumes. Therefore, two studies were set in order to understand the possible mechanisms of resistance in cowpea genotypes on their reaction to the parasitic weed. In the first experiment, Mkanakaufiti, IT99K-7-21-2-2XIT82E-16, Sudan 1 and IT82E-16 were grown in Alectra infested and non-infested pots. The experiment (2*4 factorial treatment combination) was arranged in an RCBD and replicated eight times. The second experiment, involved Petri-dish techniques where 4 genotype roots were assessed on their ability to stimulate the germination of A. vogelii as a proxy for germination stimulant production. The experiment was arranged in an RCBD and replicated five times. In the first experiment, data was collected on;the number of days to first Alectra emergence, Alectra shoot counts at 6, 8, 10, and 12 weeks after planting (WAP), Alectra attachment at 5 and 12 WAP, Alectra biomass at 12 WAP, cowpea biomass parameters at 5 and 12 WAP, yield and yield components per pot. While in the second experiment, number of germinated Alectra seeds per Petri dishes was recorded. The results indicated that IT82E-16 (33.25 days) and Sudan 1 (34.25 days) were earlier infested whilst late on IT99K-7-21-2-2XIT82E-16 (38 days) which correlated to the number of Alectra attachments. There were significant differences (p = 0.05) in weekly Alectra counts between cowpea varieties from 6 up to 10 WAP. Mkanakaufiti and IT99K-7-21-2-2XIT82E-16 were observed with no and few Alectra shoots infestation respectively which was an indicator of resistance mechanism in the study. Number of pods, grain weight (g) and harvest index per pot were significantly affected by inoculation protocol with lower yield on infested cowpea genotypes. The same trend was observed on cowpea varieties where Mkanakaufiti (21.9 g/pot) shown higher yield followed by IT82E-16 (12.5 g/pot) which is susceptible but with tolerance ability to the parasitic weed. The stud展开更多
Bambara groundnut (BGN) is a protein-rich pulse with the ability to lead to more climate-resilient agriculture. The objective of this study was to review Alectra vogelii as a potential threat to BGN production as a re...Bambara groundnut (BGN) is a protein-rich pulse with the ability to lead to more climate-resilient agriculture. The objective of this study was to review Alectra vogelii as a potential threat to BGN production as a result of climate change. However, the crop faces biotic and abiotic stresses. Alectra vogelii is a major biotic constraint to BGN production, especially in Africa’s non-fertile semi-arid regions. Alectra vogelii (L.) Benth is a parasitic weed in the Orobanchaceae family that causes major damage by forming haustoria attached to roots to enable absorption of nutrients from the BGN. Alectra vogelii produces a large number of minute seeds that can live in the soil for up to 20 years. Based on the reviewed literature, various control mechanisms for dealing with the harmful effects of Alectra vogelii have been proposed. The aim of this research was to reveal the effect of Alectra vogelii on BGN and possible control strategies. We discuss the different control methods such as cultural and mechanical management procedures, phosphorus fertilizers and resistant host crops, herbicide use, and integrated Alectra vogelii control methods. In adaptive methods, however, new techniques remain important. The life cycle of root parasitic weeds is inextricably linked to that of their host, making it an ideal target for such new control techniques, especially when aimed at the early stages of the host-parasite relationship. This review reveals additional information on the function of parasitic seed, strigolactones and how they can be used in breeding to management parasitic weeds.展开更多
文摘Parasitic angiosperm Alectra vogelii Benth is a growing problem in Malawi, particularly with current emphasis on legumes. Therefore, two studies were set in order to understand the possible mechanisms of resistance in cowpea genotypes on their reaction to the parasitic weed. In the first experiment, Mkanakaufiti, IT99K-7-21-2-2XIT82E-16, Sudan 1 and IT82E-16 were grown in Alectra infested and non-infested pots. The experiment (2*4 factorial treatment combination) was arranged in an RCBD and replicated eight times. The second experiment, involved Petri-dish techniques where 4 genotype roots were assessed on their ability to stimulate the germination of A. vogelii as a proxy for germination stimulant production. The experiment was arranged in an RCBD and replicated five times. In the first experiment, data was collected on;the number of days to first Alectra emergence, Alectra shoot counts at 6, 8, 10, and 12 weeks after planting (WAP), Alectra attachment at 5 and 12 WAP, Alectra biomass at 12 WAP, cowpea biomass parameters at 5 and 12 WAP, yield and yield components per pot. While in the second experiment, number of germinated Alectra seeds per Petri dishes was recorded. The results indicated that IT82E-16 (33.25 days) and Sudan 1 (34.25 days) were earlier infested whilst late on IT99K-7-21-2-2XIT82E-16 (38 days) which correlated to the number of Alectra attachments. There were significant differences (p = 0.05) in weekly Alectra counts between cowpea varieties from 6 up to 10 WAP. Mkanakaufiti and IT99K-7-21-2-2XIT82E-16 were observed with no and few Alectra shoots infestation respectively which was an indicator of resistance mechanism in the study. Number of pods, grain weight (g) and harvest index per pot were significantly affected by inoculation protocol with lower yield on infested cowpea genotypes. The same trend was observed on cowpea varieties where Mkanakaufiti (21.9 g/pot) shown higher yield followed by IT82E-16 (12.5 g/pot) which is susceptible but with tolerance ability to the parasitic weed. The stud
文摘Bambara groundnut (BGN) is a protein-rich pulse with the ability to lead to more climate-resilient agriculture. The objective of this study was to review Alectra vogelii as a potential threat to BGN production as a result of climate change. However, the crop faces biotic and abiotic stresses. Alectra vogelii is a major biotic constraint to BGN production, especially in Africa’s non-fertile semi-arid regions. Alectra vogelii (L.) Benth is a parasitic weed in the Orobanchaceae family that causes major damage by forming haustoria attached to roots to enable absorption of nutrients from the BGN. Alectra vogelii produces a large number of minute seeds that can live in the soil for up to 20 years. Based on the reviewed literature, various control mechanisms for dealing with the harmful effects of Alectra vogelii have been proposed. The aim of this research was to reveal the effect of Alectra vogelii on BGN and possible control strategies. We discuss the different control methods such as cultural and mechanical management procedures, phosphorus fertilizers and resistant host crops, herbicide use, and integrated Alectra vogelii control methods. In adaptive methods, however, new techniques remain important. The life cycle of root parasitic weeds is inextricably linked to that of their host, making it an ideal target for such new control techniques, especially when aimed at the early stages of the host-parasite relationship. This review reveals additional information on the function of parasitic seed, strigolactones and how they can be used in breeding to management parasitic weeds.