The Study On Seed Development And Indicators Of Physiological And Biochemical Of Cucumber、Pumpkin And Cucurbit

Using cucumbers, pumpkins and cucurbit as the test materials in this experiment, westudy the seed germination, the content of storage material component in seed and the contentof enzymes and hormones related with seed vigor in seed and pulp in different parts of thefruit in different harvest period. The specific test results are as follows:1Different harvest time of the seeds, after pollination in about35days, the seedgermination rate and germination potential of cucumber seed reach the maximum value, bothare87%, TKW (Thousand Kernel Weight) is28.88g; after pollination in about46days, thegermination rate, germination potential and the TKW of the pumpkin reach the maximumvalue, respectively,75.4%,74.9%and99.45g; after pollination in about51days, the seedgermination rate, germination potential and TKW of cucurbit reach the maximum value,respectively,37.9%,37.6%and124.52g.2After pollination in about32days, the dehydrogenase content of cucumber seed reachthe maximum value to16.75ug/g; the SOD content and POD activity of the cucumber seedreach the highest point, respectively10.23U/mg and96.61△OD470g-1FW min-1in about35days; IAA and GA content reach the maximum value in the first29days after pollination,respectively,759ng/g and711ng/g, indicating that the seeds are in the fast-growing period;soluble protein and starch content in the seeds reach the maximum value in about32afterpollination,respectively29.89mg/g and26.4%, indicating that the accumulation of nutrientshas been basically completed.3The dehydrogenases content of the pumpkin has been always higher, on average19.28ug/g after pollination in about35-46, indicating that the seed vigor of this period isrelatively high; the IAA and GA content reach the maximum value after pollination in the first38days, respectively,549and491ng/g, indicating that the seed is in the rapid growth period;soluble protein and starch content get the highest point in the first46days, respectively,33.89mg/g and31.7%.4The dehydrogenase content, SOD content and POD activity of gourd seed are higherafter pollination in the first51days, respectively9.68ug/g,12.12U/mg and37.15△OD470g-1FW min-1; IAA and GA content reach the highest value in about39daysafter pollination, were531ng/g and458ng/g, indicating that the seed has passed the rapid growth period in the first51days; the soluble protein and starch content in the seeds reach themaximum value in the first48days harvested in48days, respectively34.39mg/g and24.4%,accumulation of nutrients have been completed in the first51days.5During fruit development, the maximum content of soluble protein in pulp appearsearlier than in seeds; the maximum value of the IAA and GA content also appears earlier inpulp than in seeds, indicating that the fruit pulp growing earlier than in the growth of seeds.Dehydrogenase content, SOD content, POD activity and α-amylase enzyme activity has littlerelevance with the enzymes in seeds.6The seeds in different parts of the fruit in the same harvest period, in the middle part ofthe fruit, the germination rate, germination potential, grain weight and enzyme content relatedwith the seed vigor and hormone content are the highest, the tail follows the middle and theseindicators in head are the smallest, meanwhile these indicators in the middle part and tail parthave no significant difference.7In this experiment, the seeds of cucumbers and gourds will germinate in the melon asthe harvest time extended, so for these kinds of seeds we must harvest them before theygerminate when they are in the physiological maturity stage and finish accumulating nutrient.For those seeds which won not vivipary in the melon, can be appropriate to extend the harvesttime.