Abstract:
Rice brown spot produced by Cochliobolus miyabeanus
(Ito&Kuribayashi) fungus is the most frequent rice disease in Romania. In
this paper authors collective has followed influences urea and complex NPK
fertilizer applied in different doses concerning this disease. Experience has
located in green house, been organized in 10 variants of 3 repetition each
variant. Six variants has represented different urea doses (50 kg active
ingredient./ha, 100 kg a.i /ha, 150 kg a.i /ha, 200 kg a.i /ha, 250 kg a.i /ha,
300 kg a.i /ha), three variants has represented different NPK 15:15:15 doses
(100 kg a.i /ha, 150 kg a.i /ha, 200 kg a.i /ha), in time of one variant has
represented unfertilized variant. After fertilizer applying at rice plants it has
effected three notations. It has noted Cochliobolus attack frequency and
intensity at all experimental variants, on this base it has calculated attack
degree (GA %). At first notations attack frequency has values between 33,33
% and 65 %. Attack degree (GA %) has low values. At second notations,
attack frequency has bigger values then 60 %. Both attack intensity and
degree has bigger values at variants with maximum fertilizer (urea and
NPK). At last notations, variants fertilized with maximum dose of urea and
NPK have the bigger values of attack degree, from all experimental variants.
The attack degree (GA %) ranged from 1,34 % at variant fertilized with 150
kg urea a.i./ha and 3,28 % at variant fertilized with 300 kg urea a.i./ha. The
control variant has an attack degree by 1,69 %
