The wheat harvest at the end of wax ripening is of high quality and high yield.

In recent years, researchers have studied the grain filling rate of several @ # @ 245 wheat varieties, and the 1000-grain weight is the maximum at the end of wheat wax ripening. After 3 days of harvest, the average daily weight per 1000-grain weight decreased by 0.3-9.4 g, while that per 1000-grain weight decreased by 1-1.2 g per day from the 4th to 5th day. If it is calculated according to 350000 ~ 400000 ears per mu and 35 grains per panicle, the yield will be reduced by 1315kg per mu when the 1000-grain weight is reduced by 1g.

The results show that the harvest of wheat is the most suitable at the end of wax ripening, because the nutrients of stems and leaves transfer sharply to the grains at the milk stage, slow down after entering the wax ripening stage, and basically stop at the later stage of wax ripening. At this time, the accumulation of nutrients in the grain reached the peak, the quality was the best and the yield was the highest. After the full ripening stage, the roots, stems and leaves of wheat successively dried up and could no longer produce nutrients, but it was still breathing and needed to consume nutrients, so the hydrolytic backflow of nutrients appeared, resulting in the decrease of 1000-grain weight, grain thickness and color difference, affecting yield and quality. secondly, in the full-mature stage, because the wheat awn and grain are loose, the ear axis is fragile, and it will swing and friction in case of windy weather, and it is inevitable to drop ears and grains. If there is a rainy day, the loss will be even greater if the harvest is not collected in time. Long-term practice has also proved that the yield of wheat harvested in the full ripening period is about 10% lower than that in the later stage of wax ripening, and the content of starch and protein is reduced by about 5%. Therefore, wheat has a proverb "well-done, 100% harvest, 10% maturity, 10% loss".

In order to harvest wheat at the right time, the key is to scientifically grasp the appearance of wheat at the end of wax ripening. The maturity of wheat can be divided into three stages: milk ripening, wax ripening and full ripening. Among them, the wax ripening stage can be divided into early wax ripening stage, middle wax ripening stage and late wax ripening stage. Wheat in the early stage of wax ripening, with nails to pinch the wheat grain, the wheat grain is easy to break, will flow out of things like solidified wax, with a knife to cut the wheat grain, although it can be cut off, but will be deformed, the wheat grain water content in this period is about 30%. Wheat to the middle stage of wax ripening, the grain is full and wet, pinching wheat flour with fingernails, there can be traces, cutting wheat grain with a knife is easy to break, but does not deform, the water content of wheat grain in this period is about 25%. In the late stage of wax ripening, the grain was yellowish wax. at this time, except for the yellowish green on the two nodes of the plant, the leaves, internodes and spikes all turned yellow, and the grain water content was about 20%. After the wheat reached the full ripening stage, the grain hardened and the water content decreased to less than 16%.

When checking the grain, the representative spike of the land should be selected, and then the middle grain of the spike should be taken for inspection, because the same spike wheat does not mature at the same time, but gradually matures from top to bottom.

"the summer seed should be the first, and the wheat harvest should be the first to rob the sky." To harvest wheat, we should reasonably arrange the best harvest time and scientific harvest according to the weather, the situation of the harvester, labor and other specific conditions, so as to achieve a bumper harvest.