At the experimental field "Radmilovac" of the Faculty of Agriculture of the University of Belgrade the study of the conservation of soil moisture in deep tillage Rigosol was carried out. The so called type of soil Rigosol was covered by wheat and maize. The Rigosol was formed by special treatment of the parent soil the Eutric Cambisol. The researches have been conducted during the most important phenophases of the crop growth, including formation of kernels, flowering, fertilization, grain filling and maturity.

Phenological stages of white wine varieties grown in the "Radmilovac" collection vineyard were recorded during a three- year period. The included stages were: time of bud burst - shoot growth, flowering, véraison and full ripening. The number of days, sum of active and sum of effective temperatures were established for each phenological stage, 12 features in total.

The results of two-year investigations of buckwheat raised in agroecological conditions of South Banat (Pančevo) and West Serbia (Gorobilje) are presented in the paper. Based on the obtained investigation data, we confirm the hypothesis that buckwheat is a plant suited to more humid regions, since we have determined higher yield of the plant on locations with higher precipitation amount. During 1999, the yield of buckwheat was higher at the location in Pančevo and the next year at the location in Gorobilje.