Abstract:

The experiment was carried out from 2011 to 2013, to study the effects of waterlogging on grain yield in wheat and the effect of spraying 6BA before waterlogging. The results were shown as follows. The precipitation was enough during grain filling both during 2011-2012 and 2012-2013 in Jianghan Plain. The accumulated rainfall was 1941 mm from April to May 31 in 2012, and 285.5 mm in 2013, respectively. The above data indicated that there was great risk of waterlogging in wheat. The experimental research indicated that after waterlogging from anthesis to 7 d after anthesis, the plant of wheat aged more quickly, and leaves turned yellow seriously. Spraying 6-BA before waterlogging slowed down the course of senescence. Waterlogging after anthesis decreased photosynthetic rate in flag leaf and spraying 6-BA slowed down the decrease of photosynthetic rate but its photosynthetic rate was still less than that of CK. Waterlogging decreased root activity as well. The root activity of waterlogging treatment was 563 percent of CK, and the activity of root from 6-BA+waterlogging treatment was 629 percent of CK at grain filling stage, which means spraying 6-BA delayed senescence in root. Finally, the treatment of 6-BA + waterlogging improved 77 percent in biomass and 13.7 percent in grain yield, respectively. All of the above, under this experimental condition, the waterlogging from anthesis to 〖JP2〗anthesis of 7 d later decreased photosynthetic rate in flag leaf, root activity, biomass and grain yield, spraying 6-BA before〖JP〗 waterlogging could decrease the effects of waterlogging, improving grain yield filling after waterlogging. As estimated from the data of grain yield during 2011-2012 and 2012-2013, grain yield increased about 427 kg per 6667 m2, which means about onethird of the field was free from waterlogging