Effect Of Sowing Depth And Plant Growth Substances On Coloptile Built And Seedling Growth Of Maize

The coleoptile building and seedling vigor is the beginning in plant growth and yield ofmaize during the growth period. The purpose of this study was to investigate the effect of sowingdepth and plant growth substance on the growth coleoptile building and seedling vigor inmazie.The independent breeding mazie variety Zhengdan958, Demeiya1and Longdan49wasused to study the effects of different sowing depth(2cm,4cm,6cm,8cm,10cm) and plantgrowth substance (Gibberellin15mg/L, Mepiquat Chloride50mg/L,30%Hydrogen peroxide0.8mL/L)on seedling emergence, seediling vigor, coleoptile morphology, coleoptilemicrostructure and physiology index. In2014, Jinong516and Dongnong252were used inLindian cunty of Heilongjiang province to study the effect of plant growth substances which wasselected to yield and yield component of maize. The following findings were revealed:1. The seedling emrgence potential and germination rate decreased with sowing depth increased.The seedling emrgence potential, emrgence and seedling vigor of4cm was best, and theemrgence potential reached a significant difference(P<0.01) with other sowing depth treatment.2.0.8mL/L30%hydrogen peroxide treatment could increase maize seedling emergence potentialand emergence.3. With the increasing of planting depth, dry weight and length of coleoptile increased, the length,weight of coleoptile increased, and increased more than27%compared with2cm sowing depth.At the same time, the coleoptile vascular thickened, the longitudinal parenchyma cells ofcoleoptile became shorter.4.15mg/L gibberellin treatment increased the length, width and weight of coleoptile.50mg/Lmepiquat chloride could effectively increase the vascular bundle area, the thickness of parenchyma cell where vascular bundles stay, shorten the length of parenchyma cells in the coleoptilelongitudinal.5.50mg/L mepiquat chloride increased the content of SOD, POD and CAT of coleoptile,reduced the content of MDA.50mg/L mepiquat chloride treatment all increased content ofhemicellulose and cellulose, effectly enhanced the ability of mechanical strength.6.15mg/L gibberellin treatment increased the content of expansin in coleoptile, making itsrapidly growth. 7. Three kinds of plant growth substance could promote the yield of maize in which hydrogenperoxid treatment was the best. There are differences between varieties in yield.