ISSN:
1573-5036
Keywords:
Beans
;
N uptake
;
N2 fixation
;
Phaseolus vulgaris
;
N distribution
;
15N
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary The uptake and distribution of15NH 4 + ,15NO 3 − and15N2 was studied in greenhouse-grown beans (Phaseolus vulgaris L.) with a commercial cultivar and 2 recombinant inbred backcross lines;15N was supplied in the nutrient solution at the R3 (50% bloom) stage. Plants were harvested 1, 5 and 10 days after treatment, and were separated into nodules, roots, stems, mature leaflets, immature leaflets, and flowers/fruits. All 3 lines showed rapid increases in the N content of flowers/fruits after the R3 stage. However, the percentage N in these tissues decreased after the R3 stage. One of the recombinant lines showed a greater uptake of NH 4 + than the other 2 lines. Rates of15N2 fixation and NO 3 − uptake were similar for all 3 lines, N2 fixation estimated from total N content showed the 2 recombinant lines with 24 and 34 percent greater activity than the commercial cultivar. Distribution of15N at the whole plant level was similar for all 3 lines for a similar N source.15NO 3 − was transported first to leaflets and the label then moved into flowers/fruits. Transport of fixed N2 was from the nodules to roots, stems and into flowers/fruits; usually less than 10 percent entered the leaflets. This indicates that N2 fixation furnishes N directly to flowers/fruits with over 50 percent of the fixed N being deposited into flowers/fruits within 5 days after treatment.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02377147
Permalink
