Abstract:

Field experiments were carried out in 2010 and 2011 to investigate the best leaf age when to spray chemical control agentn Jindele of summer maize along Yanhuai River. In this study, spraying chemical control agent Jindele 450 mL/hm2 plus 225 kg of water during the period of 6 leaf age to tasseling stage were examined to investigate the effects of spraying control agent Jindele on plant height, ear height, three-ear-leaves, yield, ear row number, grain number per row and 1000-grain weight. The results showed that, spraying chemical control agent Jindele during the period of 6 leaf age to tasseling stage, with the increase of leaf age, the plant height, ear height, three-ear-leaves, yield, ear row number, grain number per row and 1000-grain weight decreased first and then increased. Plant height decreased to minimum at 14 and 16 leaf age, ear height reached minimum at 14 leaf age, three-ear leaves and grain yield reached minimum at 12 leaf age, ear row number minimized at 9 leaf age, grain number per row and 1000-grain weight minimized at 12 leaf age. Spraying chemical control agent Jindele during 10 to 18 leaf age could significantly decreased plant height, and ear height decreased significantly during 8 to 16 leaf age. There was no significant difference between spraying chemical control Jindele agent treatment and control of grain yield when to spray chemical control agent at 6, 7, 8, 16, 18 leaf age and post tasseling stage. The results indicated that, 6 to 8 leaf age were the safety leaf age to spray chemical control agent Jindele, and 8 leaf age was the best leaf age to spray chemical control agent Jindele.