Salinity-fertility interaction with macro and micronutrients in maize (Zea mays) plants
General Material Designation
[Thesis]
First Statement of Responsibility
M. M. M. Helmy
Subsequent Statement of Responsibility
J. L. Stroehlein
.PUBLICATION, DISTRIBUTION, ETC
Name of Publisher, Distributor, etc.
The University of Arizona
Date of Publication, Distribution, etc.
1987
PHYSICAL DESCRIPTION
Specific Material Designation and Extent of Item
71
DISSERTATION (THESIS) NOTE
Dissertation or thesis details and type of degree
Ph.D.
Body granting the degree
The University of Arizona
Text preceding or following the note
1987
SUMMARY OR ABSTRACT
Text of Note
In two greenhouse experiments, the response of maize plants (Zea mays L.) to macro and micronutrient fertilizers was studied. The first experiment was conducted in Cairo, Egypt in which maize plants were grown on saline soils with ECe values of 1.42, 6.12 and 12.1 dSm and fertilized with N, P, K alone and in combination. The second experiment was conducted in a University of Arizona campus greenhouse. A Pima soil from the Marana area was artificially salinized with NaCl, Na2SO4, CaCl2, and Mg2SO4 salts almost to the salinity levels mentioned above. Maize plants were grown and fertilized with NP fertilizer as a basic dressing. Chelated forms of Zn, Fe, and Mn were added with two different methods; soil and folair spray application. Two pH values of spray nutrient solutions were used; pH 6 and pH 8. Data obtained showed increased dry matter and nutrient uptake in response to spraying maize plants with Zn + Fe or Zn + Fe + Mn at pH value of 8 at the medium salt level relative to the other treatments. However, maize plants also showed high dry matter and nutrient uptake in response to Zn + Fe + Mn soil application at the high salt level, although Zn-pH 8 gave unexpectedly high dry matter production. It seems probable that this high dry matter obtained could be due to the effect of high pH spray treatment on increasing the activity of some enzymes, e.g. PEP-carboxylase and/or ribulose 1.5 diphosphate carboxylase, as well as the increase in rate of translocating the photosynthates and this effect was augmented by the nutrient(s) applied. Also, it was found that Na uptake decreased while total chlorophyll and chlorophyll a content increased with increasing salinity level. The increase in the chlorophyll content could be due to either Na exclusion by the plants and/or the decrease plant growth due high salts. (Abstract shortened with permission of author.)