Changes in soybean nodule number and dry weight in response to drought

Virtually no information exists on the fate of nodule numbers once drought is imposed on a legume crop. This study was undertaken on field-grown soybean (Glycine max (L.) Merr.) to observe possible short-term changes in nodule number and dry weight in response to four irrigation treatments. Two years of study showed that mild drought treatments had no significant effect on nodule number or dry weight. Only when severe drought was imposed were significant (P