title: Contribution of inoculation with azolla combined with nitrogen, phosphorus and zinc to rice in Nile Delta.
abstract: Rice performance, in terms of plant height, productive tillering, yield and N-contents of grain and straw, harvest index (grain yield as a percentage of grain plus straw yields) and relative fertilizer N-use efficiency (kg grain yield/kg fertilizer-N) was enhanced by urea, ZnSO4 and green manuring withAzolla caroliniana. Unlike urea fertilizer, calcium superphosphate increased the rate of azolla field colonization and promoted a thick, healthy dark-green mat of the fern. Response to ZnSO4 was higher in the azolla-free sub-subplots. Application of ZnSO4 corrected symptoms of Zn deficiency in rice but the addition of calcium superphosphate in the absence of Zn intensified the symptoms of Zn deficiency.
authors.affiliation: the Sakha Agricultural Research Station, 33717, Kafr El-Sheikh, Egypt.
authors.forename: Y G
authors.initials: YG
authors.lastname: Yanni