Estimation of the Amount of Symbiotic Nitrogen Fixation through the Measurements of Dry Matter Production and Evapotranspiration in Soybean (Glycine max (L.) Merr.)

Growth dynamics, water relations, and photosynthesis of soybean [Glycine max(L.) Merr. ‘Ransom’], common cocklebur (Xanthium pensylvanicumWallr.), jimsonweed (Datura stramoniumL.), prickly sida (Sida spinosaL.), sicklepod (Cassia obtusifoliaL.), smooth pigweed (Amaranthus hybridusL.), spurred anoda [Anoda cristata(L.) Schlect.], and velvetleaf (Abutilon theophrastiMedic.) were compared in a controlled-environment greenhouse programmed for 32C day and 23C night temperatures. Net photosynthetic rates, net assimilation rates, and water-use efficiency on a whole-plant or single-leaf basis were greatest in the C4-plant, smooth pigweed. Total dry-matter production at 29 days after planting was greatest in common cocklebur and least in jimsonweed. Interspecific differences in dry-matter production were highly positively correlated with leaf area duration and negatively correlated with net assimilation rate. Threshold leaf water-potential levels causing stomatal closure varied among species. The stomata of jimsonweed were the most sensitive to water stress and those of prickly sida were the least sensitive.

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Effects of Allelopathic Chemicals on Growth and Physiological Responses of Soybean (Glycine max)

Weed Science ◽

10.1017/s0043174500025820 ◽

1981 ◽

Vol 29 (1) ◽

pp. 53-59 ◽

Cited By ~ 105

Author(s):

D. T. Patterson

Keyword(s):

Glycine Max ◽

Chlorogenic Acid ◽

Leaf Area ◽

Chlorophyll Content ◽

Dry Matter ◽

Dry Matter Production ◽

Sulfosalicylic Acid ◽

Leaf Production ◽

Unit Leaf ◽

Matter Production

The effects of caffeic acid, chlorogenic acid,t-cinnamic acid,p-coumaric acid, ferulic acid, gallic acid,p-hydroxybenzaldehyde, 5-sulfosalicylic acid, vanillic acid, and vanillin on growth, photosynthesis, water relations, and chlorophyll content of 3-week-old soybeans [Glycine max(L.) Merr. ‘Tracy’] grown in aerated nutrient solution were determined. At concentrations of 10−3M, caffeic,t-cinnamic,p-coumaric, ferulic, gallic, and vanillic acids significantly reduced dry matter production, leaf expansion, height, leaf production, net assimilation rate (rate of dry matter production per unit leaf area), and leaf area duration (total leaf area present during treatment interval). Chlorogenic acid,p-hydroxybenzaldehyde, 5-sulfosalicylic acid, and vanillin at 10−3M did not inhibit growth. None of the 10 compounds at 10−4M inhibited growth. At concentrations of 10−3M, caffeic,t-cinnamic,p-coumaric, ferulic, gallic, and vanillic acids severely reduced net photosynthetic rate and stomatal conductance of single, fully expanded leaves. These same compounds also caused marked reductions in leaf chlorophyll content, with net losses of chlorophyll occurring over an 86-h period after treatment.

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Metabolite Regulation of Phosphenolpyruvate Carboxylase in Legume Root Nodules

Functional Plant Biology ◽

10.1071/pp9960413 ◽

1996 ◽

Vol 23 (4) ◽

pp. 413 ◽

Cited By ~ 2

Author(s):

KC Woo ◽

S Xu

Keyword(s):

Nitrogen Fixation ◽

Glycine Max ◽

Vigna Unguiculata ◽

Symbiotic Nitrogen Fixation ◽

Feedback Inhibition ◽

Root Nodules ◽

Psophocarpus Tetragonolobus ◽

Glycine Max L ◽

Fructose 1,6 Bisphosphate ◽

Metabolite Regulation

The effects of metabolic activators and inhibitors on phosphoenolpyruvate carboxylase (PEPC) activity were examined at pH 7 in partially purified enzyme from nodules of soybean (Glycine max (L.) Merr.), Psophocarpus tetragonolobus DC. and Vigna unguiculata ssp. sesquipedalis (L.) Verdc. Glucose 6-phosphate, fructose 6-phosphate, glucose 1-phosphate, fructose 1-phosphate, fructose 1,6- bisphosphate and phosphoglycerate stimulated the activity about 2-fold at low (0.5 mM) but not saturating (2.5 mM) PEP concentration. Glc 6-P and fru 6-P were the most effective activators and they increased the affinity of the enzyme for PEP by 2-4-fold. The dicarboxylates, malate, succinate, malonate, 2-oxoglutarate and aspartate inhibited PEPC activity. Malate was the most inhibitory, and strongly inhibited PEPC activity even at saturating PEP concentration. The Ki values for malate were 0.3-0.4 mM for soybean and P. tetragonolobus. However, glc 6-P and fru 6-P alleviated maiate inhibition and increased the Ki values by 11- to 28-fold in these two species. We propose that glc 6-P (fru 6-P) activates PEPC in a feedforward regulation and protects it against feedback inhibition by malate and thus coordinates the supply of photosynthate availability with malate synthesis required by the bacteroids to support symbiotic nitrogen fixation in nodules.

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CARBOFURAN EFFECTS ON ESTABLISHMENT OF LEGUMES IN RELATION TO PLANT GROWTH, NITROGEN FIXATION, AND SOIL NEMATODES

Canadian Journal of Plant Science ◽

10.4141/cjps85-057 ◽

1985 ◽

Vol 65 (2) ◽

pp. 423-433 ◽

Cited By ~ 4

Author(s):

G. BELANGER ◽

J. E. WINCH ◽

J. L. TOWNSHEND

Keyword(s):

Nitrogen Fixation ◽

Plant Growth ◽

Dry Matter ◽

Field Experiments ◽

Dry Weight ◽

Dry Matter Production ◽

Birdsfoot Trefoil ◽

Soil Nematode ◽

Matter Production ◽

Plant Stand

Field experiments were conducted to determine the effects of carbofuran on the establishment and subsequent yields of sod-seeded legumes. The effects of carbofuran on plant growth, nodulation and nitrogen fixation of birdsfoot trefoil (Lotus corniculatus L.) in non-sterilized and sterilized soil were evaluated in growth cabinet experiments. In the field experiments carbofuran, applied immediately after seeding, had a positive effect on plant stand and seedling dry matter production of birdsfoot trefoil and alfalfa (Medicago sativa L. ssp. falcata L.) in the weeks following seeding. In the first production years of these field trials, there was a trend for the total and legume yields to be higher in the carbofuran plots than where carbofuran was not used. In either growth cabinet experiment, however, shoot growth was not affected by carbofuran but a reduction in the number of plants in the non-sterilized and carbofuran pots occurred. A toxic effect of carbofuran on seedlings may have been involved. No correlation between soil nematode numbers and plant stand or dry matter production was found in either field or growth cabinet experiments. In the growth cabinet experiments, carbofuran did not affect the number of nodules but improved nitrogen fixation in sterilized pots of exp. B. Carbofuran increased the dry weight of individual nodules in the sterilized pots of exp. A but a decrease was observed in exp. B. These effects of carbofuran on the dry weight of individual nodules and specific nodule activity were also observed in the nematode-free environment created by sterilization. In view of these responses in sterile soil, it was suggested that the effect of carbofuran was not as a nematicide but rather a positive physiological effect on the plant component of the plant-rhizobium system.Key words: Carbofuran, establishment, legumes, nitrogen fixation, nematodes

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