Testing of Nicosulfurone activity on some maize inbred lines

Abstract

The Nicosulfurone is post-emergence herbicide applied in maize crop. Studies were carried out under field conditions, pointed out to a different respond of inbreds to its effects. The tree inbreds were used. Plants were grown in a phytotrone up to the tree-leaf stage. The herbicide foliar application in the amount of 0.8 and 1.25 L ha-1 was done prior to the third leaf emergence. Seven days following the treatment plants were collected to the analysis. The following was measured: length and fresh and dry weight of the shoots and roots, chlorophyll content and cell wall peroxidase activity. Equal herbicide amounts differently affected examined inbreds, since the growth was either stimulated or inhibited. Both concentrations of Nicosulfurone reduced the total chlorophyll content in all three inbreds. Only in L2, as sensitive inbred, the growth of third leaf was inhibited and the peroxidase activity was the highest. In L1, as resistant inbred, the growth wasn't inhibited, with unchanged peroxidase activity; while in L3, as tolerant inbred, the leaf velocity was unchanged, with root growth stimulation and elevated peroxidase level (in treatment with higher herbicide concentration), regarding to inhibition of root growth, with lower peroxidase level (in treatment with lower herbicide concentration).

Nikosulfuron je herbicid koji se koristi posle nicanja kukuruza. Ispitivanja u poljskim uslovima su pokazala različitu reakciju linija na njegovo dejstvo. Biljke 3 linije kukuruza su gajene u fitotronu do faze trećeg lista. Pre njegove pojave tretirane su folijarno sa 0.8 i 1.25 L ha-1 Nikosulfurona. Sedam dana nakon tretmana merene su dužina i masa svežeg i suvog izdanka i korena, sadržaj hlorofila i aktivnost peroksidaze ćelijskog zida. Iste količine herbicida različito su delovale na ispitivane linije, te je došlo, kako do stimulacije, tako i do inhibicije rasta. Nikosulfuron je izazvao smanjenje sadržaja ukupnog hlorofila, kod sve tri linije, pri obe koncentracije. Samo je kod L2 (osetljive linije) došlo do inhibicije rasta trećeg lista, gde je i aktivnost peroksidaze bila najveća. Kod L1 (otporne linije) nije bila prisutna inhibicija rasta, uz nepromenjenu aktivnost peroksidaze; kod L3 (tolerantne linije) nije došlo do promene brzine rastenja listova, dok je bila zabeležena stimulacija rasta korena, uz veći nivo peroksidaze (pri većoj koncentraciji herbicida) i inhibicija rasta korena, uz niži nivo peroksidaze (pri nižoj koncentraciji herbicida).