
TY  - JOUR
A1  - Rochester, I. J. 
A1  - Peoples, M. B. 
A1  - Constable, G. A. 
A1  - Gault, R. R. 
T1  - Faba beans and other legumes add nitrogen to irrigated cotton cropping systems
JF  - Australian Journal of Experimental Agriculture
JO  - Aust. J. Exp. Agric.
Y1  - 1998
VL  - 38
IS  - 3
SP  - 253
EP  - 260
KW  - 
UR  - https://doi.org/10.1071/EA97132 
N2  - Summary. Legumes have become common rotation crops in cotton cropping systems in northern New South Wales. Levels of nitrogen fixation and yield achieved on-farm were measured in commercial faba beans and other winter and summer legume crops sown after cotton over 3 years to assess the relative inputs of fixed nitrogen (N) into this system. Faba bean crops fixed up to 350 kg N/ha, removed up to 160 kg N/ha in harvested grain and contributed up to 270 kg fixed N/ha to soil N after harvest. Grain yields, N2 fixation and dry matter production were reduced in late-sown crops and those water-stressed during pod-filling, but most faba bean crops fixed almost 3 times as much N as was removed in grain. Below-ground legume N, determined with 15N shoot feeding techniques, accounted for 40% of the total crop N at peak biomass, or about 100 kg N/ha for the average faba bean crops. Residual fixed N after harvest was predicted from crop dry matter and grain yield, and this could be used to assess the contribution to soil N from faba beans. Amounts of nitrogen fixed by other legume crops ranged from 20 kg N/ha for adzuki bean and droughted lablab to more than 450 kg N/ha by irrigated soybean. Soybean, peanut and Dolichos lablab contributed more fixed N to the soil than adzuki bean, mung bean or pigeon pea under irrigated conditions. Winter crops including field peas, lentils and lupins and green-manured pasture species fixed up to 240 kg N/ha. 
ER  -

