Symbiotic N2(C2H2) Fixation by Bean

Westermann, D.T. and Kolar, J.J. (1978) Symbiotic N2(C2H2) Fixation by Bean. Crop Science. 18:986-990.

PDF 408.pdf Download (274kB)

Abstract

The response of bean (Phaseolus vulgaris L.) to N fertilization
under field conditions indicates different Rhizobia-cultivar
relationships or symbiotic N?-fixation limitations
due to the cultivars. We have used the acetylene
reduction method to determine the relative seasonal
N?(C?H?) fixation of several field-grown bean cultivars.
The relative nitrogenase activity was estimated from 3-
X 15-cm soil cores taken around the main root of a decapitated
plant. Activities rapidly increased from the
three node vegetative (V3) to early pod-filling (R3-R4)
growth stages, thereafter decreasing to zero at physiological
maturity (R9). Accumulated daily activity totals
showed a five- to sixfold difference in seasonal N?(C?H?)
fixation between cultivars, which was significantly related
to the average nodule weight and to the plant dry weight
near physiological maturity. However, cultivars
similar plant dry weights had a two- to threefold difference
in relative N?(C?H?) fixation. Seed yields and total-N
updates were also positively related. These observations
indicate that it may be possible to increase both the
symbiotic N? fixation and seed yields through plant breeding.

Item Type:	Article
NWISRL Publication Number:	0408
Subjects:	Irrigated crops > Bean / dry bean Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:52
Last Modified:	02 Feb 2017 16:10
Item ID:	339
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/339