THE USE OF CHEMIGATION TECHNIQUES FOR MINIMIZING AGRO-CHEMICAL POLLUTION

Abstract

The experiment was conducted for sunflower crop (Vedoc) in Nobaria area, which represent sandy soil condition to study the effect of fungigation on reducing thiophanate-methyl (Topsin- M) pollution in the soil (1 hr after application, 5,9,14 days after application) and sunflower seeds after harvesting. Three rates of thiophanate-methyl (1/2, 3/4and1Kg/fed) were selected for surface and subsurface drip irrigation systems 30,50 em drippers, spacing as a protecting dose after one month of planting. This designed treatments aimed to study and throw light on the fo'llowing:

1-Effect of irrigation systems on the productivity of sunflower under fungicide treatment. 2-Water use efficiency of drip irrigation systems in relation to fungicide

treatment with three levels of thiophanate-methyl fungicide.

3-Residues of thiophanate-methyl in soil and seeds sunflower cultivated under fungigation system. 4-Economic feasibility.

The obtained results could be summarized in the followings:

1- A significant increase in sunflower seed yield under surface drip irrigation at

50 em drippers, spacing was recorded (1045.8 Kg/fed) with 1/2 rate of thiophanate-methyl compared with the other treatments. Also, subsurface drip irrigation system at 50 em drippers, spacing and 20 em depth achieved the total yield of (1044.3 Kg I fed) with the same rate of thiophanate-methyl. 2- A superior perfonnance of surface drip irrigation systems 50 em drippers,

spacing in achieving high yield of sunflower in soil was obtained.