Study On The Changes Of Soluble Sugar Content In Vegetable Soybean Pod

The changes of soluble sugar in vegetable soybean(Glycine max Merr.) pod were studied by the cultivation of No.75 vegetable soybean, Black vegetable soybean, No.301 vegetable soybean and Tea vegetable soybean . The results showed the difference between the contents of soluble sugar in soybean pod of different species was significant. The date of planting, the density, the relative content of water, the date of cropping influenced the soluble sugar in soybean pod greatly. The suitable planting date in Shandong Province was the 20th of June, the density was 240,000 plants/hm2, the relative content of water in soil was 60%, the date of cropping was 40 days after flowering. The influence of mulching film on the soluble sugar was not significant. The quantity and species of fertilizer influenced the soluble sugar in pod greatly. The sequence for the effect of fertilizing was organic manure, NPK compound fertilizer, urea and the suitable amount was 53160-89437.50 kg/hm:,531.60-894.38 kg/hm2,265.80-447.15kg/hm2.As the development of soybean pod. the contents of soluble sugar, Pr, oil and starch increased and became the highest after 40 days. The content of soluble sugar increased slowly in 20~30days after flowering and increased sharply during 30-40 days after flowering. The soluble Pr and oil increased little in 10-20 days after flowering, increased much after 20 days. The starch increased fast before 30 days and increased little in 30-40 days. The Pn of leaves increased in 30 days after flowering, and still in high level after 30 days. The rate of respiration of pod changed little. The activity of amylase in soybean pod increased slowly before 20 days and thereafter increased greatly. The change of amylase and Pn in leaves had significant positive relationship with the content of soluble sugar. The leaves with higher Pn provided the strong material source for the development of soluble sugar etc. The amylase with higher activity increased the speed of the transformation of soluble sugar from starch.The content of soluble sugar in pod increased after 12 hours preserved in 10, 15 and 24 hours under the normal atmosphere temperature(day temperature26+1, night temperature 18+1). The content of soluble sugar increased most after preserved for 12 hours in 15.The content of soluble Pr and starch increased while the oil decreased after 12 hours stored in5 10 15 25 and normal atmosphere temperature. The contentof soluble Pr increased ,decreased, increased and decreased in 60 hours. The content of fat decreased ,increased and decreased while the starch increased, decrease and increased in 60 hours. The content of Vc increased more for all the treatments of preservation, while the activity of amylase changed little. The content of chlorophyll in pod increased and decreased in 60 hours. The content of chlorophyll of pod after 12 hours preserved under 15癈 and 24 hours under normal atmosphere temperature increased more than that before treatment .Therefore the temperature and time of preservation for the highest soluble sugar in the soybean pod are 12 hours under 15.