Coordination Of Paclobutrazol And Fertilizer To Alleviate Wheat Injury From Subsurface Waterlogging

In the middle and lower reaches of the Yangtze River, winter wheat (Triticum aestivum L.) is liable to waterlogging during the late period of wheat growth due to excessive precipitation which may produce a severe effect on wheat production. In order to alleviate waterlogging damage, comprehensive application of the other measures is very important in the basis of existing measures for field drainage. Aiming at Zheng-9023 (a main planting variety of wheat) to suffer from waterlogged stress in the heading stage and grain filling stage, an experiment was carried out which using a completely random block design so as to study the regulatory effects due to the coordination of plant growth regulating substance and nutrition regulation after waterlogging. The main research results are as follows:1) Aiming at Zhengmai 9023 (a main cultivar of wheat) to suffer from waterlogged stress in the heading stage, an experiment was carried out which using the nutrition regulation of NPK fertilizer after waterlogging. Compared with CK1, the treatment without NPK fertilizer, application of NPK fertilizer may reduce by 47.2% of the MDA and increase by 85.3% of chlorophyll contented in the wheat flag leaf, moreover, dressing fertilizer after waterlogging significantly improve the yield trait except the spikes per plant, enhancing the grains per spike by 24.0%,1000-grain weight by 18.5% and yield per plant by 61.7%, and by which yield loss is reduced by 27.20%-36.93% compared with the trial treatment CK1, suffering from waterlogging for continuous seven days. Comprehensively considering the effect in the yield loss, it is recommendable that is dressing nitrogen fertilizer (amount to pure nitrogen:150 kg/hm2), phosphate fertilizer (amount to P2O5 of 90 kg/hm2) and potassium fertilizer (amount to K2O of 90 kg/hm2). Thus it can be seen that waterlogging damage of wheat in the heading stage can be effectively mitigated by nitrogen, phosphate and potassium fertilizer, and severe losses in the yield may be prevented.2) Aiming at Zhengmai 9023 (a main cultivar of wheat) to suffer from waterlogged stress in the heading stage, an experiment was carried out which using plant growth regulating substance PP333 and nutrition regulation of NPK fertilizer after waterlogging. Compared with CK2, the treatment that paclobutrazol PP333 is merely applied to spray on the leaves of wheat, coordination of paclobutrazol and NPK fertilizer may reduce by 26.9%of the MDA and increase by 8.7%of chlorophyll contented in the wheat flag leaf, enhance the grains per spike by 25.0%,1000-grain weight by 17.2%and yield per plant by 61.4%. Thus it can be seen that waterlogging damage of wheat in the heading stage can be effectively mitigated by coordination of paclobutrazol and NPK fertilizer, and severe losses in the yield may be prevented.3) Aiming at Zhengmai 9023 (a main cultivar of wheat) to suffer from waterlogged stress in the heading stage, an experiment was carried out which using the plant growth regulating substance 6-BA and nutrition regulation of nitrogen, phosphate and potassium fertilizer after waterlogging. Compared with CK2, the treatment that 6-BA is merely applied to spray on the leaves of wheat, coordination of 6-BA and nitrogen, phosphate and potassium fertilizer may reduce by 48.1% of the MDA and increase by 63.2% of chlorophyll contented in the wheat flag leaf, moreover, spraying 6-BA after waterlogging significantly enhance the grains per spike and by which yield loss is reduced by 1.97%, moreover, spraying 6-BA after waterlogging meanwhile adopting top dressing fertilizer further improve the yield trait except the spikes per plant, enhancing the grains per spike by 16.3%,1000-grain weight by 16.5% and yield per plant by 57.0%, and the yield loss is reduced by 27.96%-37.23% based on the yield per plant. Comprehensively considering the effect in the yield loss, it is recommendable that is spraying 6-BA after waterlogging, and then dressing nitrogen fertilizer (amount to pure nitrogen:150 kg/hm2), phosphate fertilizer (amount to P2O5 of 90 kg/hm2) and potassium fertilizer (amount to K2O of 90 kg/hm2). Thus it can be seen that waterlogging damage of wheat in the heading stage can be effectively mitigated by coordination of 6-BA and nitrogen, phosphate and potassium fertilizer, and severe losses in the yield may be prevented.4) Aiming at Zheng-9023 (a main cultivar of wheat) to suffer from waterlogged stress in the grain filling stage, an experiment was carried out which using the plant growth regulating substance 6-BA and nutrition regulation of nitrogen, phosphate and potassium fertilizer after waterlogging. Compared with CK2, the treatment that 6-BA is merely applied to spray on the leaves of wheat, coordination of 6-BA and nitrogen, phosphate and potassium fertilizer may reduce by 30.0% of the MDA and increase by 128.9% of chlorophyll contented in the wheat flag leaf, moreover, spraying 6-BA after waterlogging meanwhile adopting top dressing fertilizer further improve the yield trait except the spikes per plant, enhancing the grains per spike by 57.2%,1000-grain weight by 17.3% and grain yield by 39.2%, compared with the trial treatment only to spray 6-BA on the leaves after wheat suffering from waterlogging for continuous seven days. Meanwhile, a very significant effect was obtained that by coordination of 6-BA and nitrogen, phosphate and potassium fertilizer fertilizer the yield reduction is only 2.9%-8.9% compared with the normal contrast. Comprehensively considering the effect in the yield loss, it is recommendable that is dressing nitrogen fertilizer (amount to pure nitrogen:150 kg/hm2), phosphate fertilizer (amount to P2O5 of 90 kg/hm2) and potassium fertilizer (amount to K2O of 90 kg/hm2). Thus it can be seen that waterlogging damage of wheat in the grain filling stage can be effectively mitigated by coordination of 6-BA and nitrogen, phosphate and potassium fertilizer, and severe losses in the yield may be prevented.