Effects Of Rainfall At Harvest On Spring Wheat Ear Germination And Yield And Quality

In order to explore the suitable harvesting period of spring wheat in Heilongjiang,the temperature and humidity conditions of per-harvest sprouting in the mature period,and determine the effect of different germination processes and proportions on the quality of flour,the main planting wheat Longfumai No.1,Longmai 35 and Kechun No.8 is the experimental materials in this region.Analyze the effects of different harvest period and raining during harvest season on the yield and quality of wheat;the effects of different temperature and humidity conditions on the per-harvest sprouting of mature wheat;effect of mixing grains of different germination types with normal wheat in weight ratio on wheat quality.The main results are as follows:1.With the postponement of the harvest period,spike weight,spike grain weight and harvest index of wheat plants gradually decreased,among them,the late-maturing varieties Longmai 35 and Kechun No.8 decreased significantly;Raining during harvest season significantly reduced the spike weight and spike grain weight of the three wheat plants.2.With the postponement of the harvest period,the thousand-grain weight of wheat showed a decreasing trend,and the yield decreased significantly,the yields of Longfumai No.1,Longmai35 and Kechun No.8 harvested at the end of maturity were reduced by 6.5%?7.0%?5.9%,compared with the end of wax maturity;Raining during harvest season significantly reduces thousand-grain weight,and yield,the yields of Longfumai No.1,Longmai 35 and Kechun No.8harvested after rain decreased by 8.6%?11.5%?11.5%.3.With the postponement of the harvest period,Longmai 35 and Kechun No.8 increased the nitrogen content of stems and leaves,decreased the nitrogen content of grains,and deteriorated the rheological properties of dough;Except flour absorption rate and farinograph quality index,the rest of the quality index decreased significantly;The stretching parameters showed a downward trend,but the difference was not significant;Raining during harvest season significantly reduced the volume weight,nitrogen content,starch content,wet gluten content decreased,among which Longfumai No.1 and Longmai35 decreased significantly;the rheological properties of dough were significantly reduced.The water absorption rate and mixing tolerance index of the dough are significantly increased,and the other flour quality parameters have a large decline,the stretching parameters significantly reduced.4.The interaction of temperature and humidity has a significant effect on the per-harvest sprouting process at the mature period.At the same temperature,RH80% treatment delays whole ear moisture change rate,delays the start time of per-harvest sprouting,reduces the per-harvest sprouting rate,and reduces the ?-amylase activity,thousand-grain weight decreases slowly;Under the same humidity,with the increase of temperature,the whole ear moisture change rate gradually decreases,the germination start time is prolonged,the ?-amylase activity is reduced,the per-harvest sprouting rate,and the germination energy,and thousand-grain weight is slowed down.15°C RH90%(T1H3)significantly increased the per-harvest sprouting rate.On the third day,the germination rate of Longmai 35 reached 46.77%,and the theoretical yield decreased by 16.0%,and the germination rate Longfumai No.1 reached 20.61% and the theoretical yield decreased by 10.3%.At 25?RH80%(T3H1)treatment inhibited the per-harvest sprouting process of Longfumai No.1 in the mature period,and per-harvest sprouting rate on the 7th day was only 15.32%.However,per-harvest sprouting process of Longmai 35 was the slowest under 25?RH90%(T3H3)treatment,and per-harvest sprouting rate on the 7th day was only 27.87%.15?RH90%(T1H3)treatment can significantly accelerate the whole ear moisture change of mature spring wheat,enhance ?-amylase activity,increase per-harvest sprouting rate and germination energy,and severely reduce per-harvest sprouting resistance.5.With the increase of the mixing ratio of different per-harvest sprouting types and normal wheat,the quality of wheat gradually decreases.When the mixing ratio of germinated wheat and normal wheat reaches 5%,the starch content of grains decreases significantly;the mixing of wheat with different germination processes has no effect on the protein content of grains,but significantly reduces the protein quality.When the mixing ratio of water-soaked wheat reaches5%,the wet gluten content and water absorption rate decrease significantly;When the mixing ratio of sprouted and germination type reaches 1%,the quality parameters decrease significantly compared with the control;In the sprouting type grains,with the increase of the mixing ratio,the gluten index,falling number,stretching area,maximum stretching resistance and other indicators decreased significantly among the various mixing treatments.In summary,15°CRH90%(T1H3)are the best conditions for the "plastic bag moisture retention method" to determine per-harvest sprouting of spring wheat.Continuous raining during the harvest season will significantly reduce wheat yield and quality.When the mixing ratio of water-soaked wheat(J)reaches 5%,the wet gluten content and water absorption rate decrease significantly;the mixing of spourting(M)and germination(F)types reached 1%,the quality parameters decreased significantly compared with the control.