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Showing papers on "Polygonum published in 1968"


Journal ArticleDOI
TL;DR: In this article, the authors compared wheat and wild buckwheat with three levels each of soil fertility and soil moisture, and harvested at three dates, and found that wheat was a better competitor than wildbuckwheat when con- sidering dry matter production.
Abstract: An experiment was conducted comparing wheat (Triticum aestivurn L., var. Pembina) and wild buckwheat (Polygonum con- volvulus L.) grown alone in pots, in full competition, and in root competition at three levels each of soil fertility and soil moisture, and harvested at three dates. Wheat was a better competitor than wild buckwheat when con- sidering dry matter production. With each succeeding harvest, the dry matter production and the total nitrogen and phosphorus uptake increased more for plants grown alone than in competition. Conm- petition caused a reduction in the nitrogen and phosphorus content of wheat and wild buckwheat at the first harvest, while reductions in dry matter did not occur until the second harvest. Wheat in- creased in dry matter and nitrogen more than wild buckwheat with each higher level of soil moisture when grown alone but not when in competition. When grown alone or in competition, wheat in- creased linearly in dry matter production with increases in fertility while wild buckwheat produced maximum dry matter with medium fertility. The total nitrogen increased in wheat and wild buckwheat with each higher level of fertility, while total phosphorus increased only in wheat. Wild buckwheat used less water than wheat to produce a gram of dry matter and per milligram of phosphorus uptake when grown alone, while the plants in competition were intermediate in water usage to plants grown alone. Wild buckwheat and wheat used similar amnounts of water per unit of nitrogen uptake when grown alone anid increased their water usage when grown in competition. Water efficiency for nitrogen and phosphorus uptake and dry matter pro- (luction uisually decreased with plant maturity and higher soil moistture, and increased with higher soil fertility.

29 citations



Journal ArticleDOI
28 Jun 1968-Science
TL;DR: Seeds of four species of Polygonaceae were tested for lectins that precipitate human and animal serums and specific precipitate bands developed that enhanced and increased in number when extracts were tested against serums from patients with certain diseases.
Abstract: Seeds of four species of Polygonaceae were tested for lectins that precipitate human and animal serums. Rumex crispus, Polygonum convolvulus, and Polygonum pennsylvanicum developed specific precipitate bands on double diffusion on agar gel plates. These bands were enhanced and increased in number when extracts were tested against serums from patients with certain diseases. When tested against lyophilized serum, no precipitate bands developed. The active substance cannot be dialyzed through cellulose membrane against running tap water for 16 hours, and it is heat stable. Extracts from Fagopyrum esculentum developed no precipitate bands.

2 citations