Buckwheat
Growing Period | Type | Annual or Perennial | Drought Tolerance | Shade Tolerance | Salinity Tolerance |
---|---|---|---|---|---|
Warm Season | Forb | Annual | Low | Low | Intolerant |
Common Name
Scientific Name
Cultivar
Old cultivars of buckwheat are 'Tempest' and 'Tokyo,' which are small seeded and mature during midseason. The large-seeded varieties 'Mancan' and 'Manor' are now prevalent, and mature similarly but have larger stems and leaves (Gubbels et al., 1990).
New large-seeded buckwheat varieties 'Mancan' and 'Manor' developed in Canada feature large leaves and stems and vigorous growth. Experiments are also being conducted using semi-dwarf types of buckwheat, for resistance to lodging (Gubbels and Campbell, 1986).
Seed Description
Mature Plant Description
Temperature
Geographic Range
Water
Nutrients
Soil pH
Soil Type
Shade Tolerance
Life Cycle
Seeding Rate
Seeding Depth
Seeding Method
Seeding Dates
Inoculation
Seed Availability
Days to Flowering
Days to Maturity
Seed Production
Growth Habit
Maximum Height
Root System
Buckwheat is termed a deep rooter by Pears et al. (1989), but this is apparently an error (Bugg, pers. obs.). Rooting system is superficial but does show a high root volume in the upper soil stratum (0.0-0.25 m in depth) (Bugg, pers. comm.).
The ability of buckwheat to acquire phosphorus was characterized by investigating P uptake, morphological features, and chemical changes in the rhizosphere. Root weight and length, and frequency of root hairs were higher when plants were grown under P-deficiency. P uptake rates were only moderate, concentrations of P in the shoot were high (1.8% of dry weight). Release of Mn from MnO2- and P from FePO4- and glucose-6-phosphate was not due to a buildup of organic acids in the rhizosphere, but P release was due to high activities of acid phosphatase for plants grown with low P. The following parameters in which buckwheat is outstanding were regarded as important for its P efficiency: (1) a finely divided root system of considerable length with a high ratio of root surface to root or shoot length; (2) a high storage capacity for inorganic P; (3) an increased release of protons and FePO4- or MnO2- solubilizing substances by P-deficient plants; (4) a favorable ratio of P uptake to root mass increase, especially at low P supply; and (5) a high acitivity of acid phosphatase in the rhizosphere and the capability to use P from organic sources. (Annan and Amberger, 1989).
Establishment
Maintenance
Incorporation
Uses
Buckwheat is a fast-growing, frost-sensitive dicotyledonous (broad-leafed) plant used as a summer green manure, and it is sometimes grown immediately after an area is cleared for agriculture (Johnny's Selected Seeds, 1983.). Fast-growing annuals such as buckwheat or oat may be used during the growing season to prepare for transplants or to protect soil during short periods when it would otherwise be bare (Gershuny and Smillie, 1986).
According to Schonbeck (1988), in the Northeast, buckwheat is commonly used for summer cover and weed control; buckwheat was used for weed control by 16 of 51 farms using cover crops in the Northeast. Buckwheat can also be used to make P and other nutrients more available and to improve soil structure. Buckwheat crops or residues can inhibit weed germination, and several growers and researchers suspect that allelopathy may be involved. Decomposing buckwheat roots can inhibit weed germination, and a buckwheat intercrop can save weeding in squash. Some growers have reported inadequate control of quackgrass and other stubborn weeds by buckwheat. Buckwheat produces much less biomass than do other summer cover crops, such as sudangrass (Schonbeck, 1988).
Mixtures
Biomass
N Contribution
Non-N Nutrient Contribution
Buckwheat can be used to make P and other nutrients more available (Schonbeck, 1988).
The ability of buckwheat to acquire phosphorus was characterized by investigating P uptake, morphological features, and chemical changes in the rhizosphere. Root weight and length, and frequency of root hairs were higher when plants were grown under P-deficiency. P uptake rates were only moderate and concentrations of P in the shoot were high (1.8% of dry weight). Release of Mn from MnO2- and P from FePO4- and glucose-6-phosphate were not due to a buildup of organic acids in the rhizosphere, but P release was due to high activities of acid phosphatase for plants grown with low P. The following parameters in which buckwheat is outstanding were regarded as important for its P efficiency: (1) a finely divided root system of considerable length, with a high ratio of root surface to root or shoot length; (2) a high storage capacity for inorganic P; (3) an increased release of protons and FePO4- or MnO2- solubilizing substances by P-deficient plants; (4) a favorable ratio of P uptake to root mass increase, especially at low P supply; and (5) a high acitivity of acid phosphatase in the rhizosphere and the capability to use P from organic sources (Annan and Amberger, 1989).
Effects on Soil
Pest Effects, Insects
Flowers are attractive to hoverflies (Syrphidae) (Pears et al., 1989): in southern Georgia, Bugg and Dutcher (1989) found adults of the following hoverfly (Syrphidae) species visiting buckwheat flowers: Allograpta obliqua (Say), Pseudodoros clavatus (Fabricius), Ocyptamus fuscipennis (Say), Ocyptamus costatus (Say), Toxomerus boscii Macquart, and Toxomerus marginatus (Say); these are aphid predators as larvae. The following predatory wasps were also observed feeding at the flowers, family and genus or species are given, with known prey items in parentheses: Sphecidae: Ammophila sp. (lepidopterous larvae), Bicyrtes quadrifasciatus (Say) (Hemiptera), Cerceris sp. (Coleoptera), Isodontia apicalis (Smith) (Orthoptera: mainly Gryllidae and Tettigoniidae), Philanthus gibbosus (Fabricius) (Hymenoptera: Mainly Apoidea), Prionyx parkeri Bohart and Menke (Orthoptera: Acrididae, Pseudoplisus phaleratus (Say) (Homoptera?), Synnevrus plagiatus (Cresson) (Unknown), Tachytes guatemalensis Cameron (Orthoptera: Acrididae); Eumenidae: Zethus spinipes variegatus Saussure, Rhyacionia frustrana (Comstock), Nantucket pine tip moth (Lepidoptera: Tortricidae), Stenodynerus sp. (lepidopterous or coleopterous larvae), Vespidae: Polistes exclamans Vier. (Mainly lepidopterous larvae). Also observed were two species of Scoliidae, parasites of Scarabaeidae (Coleoptera), were also observed: Scolia dubia dubia Say and Scolia (Scolia) nobilitata nobilitata Fab.
In Massachusetts, Bugg and Ellis (1990) assessed insects associated with buckwheat and four other cover crops: (1) hairy vetch/cereal rye, (2) sorghum, (3) annual white sweetclover, and (4) bell bean. Those workers observed 2 types of Tachinidae at the flowers: Trichopoda pennipes (F.) (a parasite of true bugs) and an unidentified species near Archytas (a parasite of caterpillars). Adults of the following aphidophagous syrphids were also seen: Allograpta obliqua (Say), Sphaerophoria spp., Syrphus spp., Toxomerus spp.; and the following non-aphidophagous syrphids Eristalis tenax (L.) and Eristalis spp.). The following species of predatory wasps also fed at the flowers (family and genus or species are given, with known prey items in parentheses): Sphecidae: Sphex ichneumoneus (L.) (Orthoptera: Gryllidae; Gryllacrididae; Tettigoniidae), Cerceris fumipennis Say (Coleoptera), Cerceris sp. (Coleoptera), Eremnophila aureonotata (Cameron) (Lepidoptera: Notodontidae), Isodontia harrisi (Fernald) (Orthoptera), Tachytes pennsylvanicus Banks (Orthoptera), Philanthus gibbosus (Fabricius) (Hymenoptera: Mainly Apoidea), Philanthus lepidus Cresson (Hymenoptera: Mainly Apoidea), Ectemnius lapidarius (Panzer) (Adult Diptera), Oxybelus uniglumis (L.) (Adult Diptera), Bicyrtes quadrifasciata (Say) (Nymphal Hemiptera: mainly Pentatomidae and Coreidae); Eumenidae: Eumenes fraternus Say (lepidopteran larvae), Monobia quadridens (L.) (lepidopteran larvae), Ancistrocerus antilope (Panzer) (lepidopteran larvae); Vespidae: Polistes fuscatus pallipes Lepeletier (mainly lepidopteran larvae), Vespula maculata (L.); Pompilidae: 2 unidentified spp. (Araneae). No Ichneumonoidea were observed imbibing at the flowers of white sweetclover, and few were observed at blooms of buckwheat. This is consistent with observations by Ozols (1964). Insidious flower bug (Orius insidiosus), a beneficial predator, and tarnished plant bug (Lygus lineolaris), a pest, were relatively abundant on buckwheat on several sampling dates. Also abundant were adult aphidophagous Syrphidae and pooled adult Sphecidae (predatory wasps).
Bugg and Ellis (1990) noted that insect visitation to buckwheat was low during afternoons, whereas insects continued to visit white sweetclover. This is consistent with Pellett's (1976) statement that buckwheat often stops producing nectar during the afternoon.
Pest Effects, Nematodes
Pest Effects, Diseases
Pest Effects, Weeds
Buckwheat is grown for weed suppression (Johnny's Selected Seeds, 1983).
As reported by Schonbeck (1988), in the Northeast, buckwheat is commonly used for summer cover and weed control; some growers use sudangrass or millet. Buckwheat was used for weed weed control by 16 of 51 farms using cover crops in the Northeast. This crops or its residues can inhibit weed germination, and several growers and researchers suspect that allelopathy may be involved. Decomposing buckwheat roots can inhibit weed germination, and a buckwheat intercrop can save weeding in squash. Some growers have reported inadequate control of quackgrass and other stubborn weeds by buckwheat.
Of 8 warm-season cover crops assessed in a pecan orchard in southern Georgia, cowpea, alyceclover, and a sorghum-sudangrass hybrid reduced weed vegetational cover better than did buckwheat (Bugg and Dutcher, 1989).