Study On The Variation Of The Main Nutrients Composition In Different Varieties Of Silage Corn During Harvest Stage

In this experiment, four silage corn varieties Jinling 37, Fengtian 9, Benyu 18 and Jinling 17 were screened as the object to study the variation of dry weight of various parts and nutrients composition in the different varieties of silage corn during harvest stage. Four varieties of silage com were planted in the farmland of Maihutu town, Wulanchabu, Inner Mongolia. Planting time of Jinling 37 was on May 2,2014; Fengtian 9, Benyu 18 and Jingling 17 was planted on April 25,2014. The machine sowing way is four thousand per acre, line spacing 50cm, stalk spacing 30cm. Samples were collected per three days for 12 times, from August 25,2014 to September 27, measuring each batch of samples’fresh weight of every part, DM content and the main nutrient content of analysis’samples. The results showed that:(1) With the extension of the growing period, the varieties of silage corn height did not change significantly (P>0.05). Plant height of Fengtian 9 was significantly lower than Jinling 37, Benyu 18 and Jinling 17 (P<0.05), in the same period of harvest, its fresh weight was not significantly different from the other three species(P>0.05). Each varieties of whole silage corn DM was significantly increased (P<0.05), the average daily increase of four varieties is about 0.35%. In the same harvest stage, Jinling 17 DM content and the highest average yield was 27.81% and 421.7g/stalk; DM content of Jinling 37 has greatest daily increases of 0.31%, at the same harvest period, has the lowest DM content and yield, respectively,24.62% and 389.2g/stalk.(2) With the extension of the growing period, each varieties corn’s ear dry weight and the percentage in whole corn dry weight are in linear increases (P<0.05), during different harvest stage. In the growing 122-149th days, four varieties’ear dry weight of an average increase of 138.75%. The kernel yield and the percentage in the whole corn dry weight presents a linear increase (P<0.05), an average of four varieties of kernel dry weight increased by 262%. In the same harvest period, the ear dry weight, kernel dry weight and the proportion in the whole corn DM yield of Jinling 17 are the highest and of Jinling 37 are the lowest.(3) With the extension of the growing period, the CP, ADF and ADL contents of the various varieties of silage corn present linear decrease (P<0.05). NDF content of Jinling 37 and Benyu 18 present increases(P<0.05). Starch content of four varieties are presented linear increases (P<0.05), four varieties average daily increase of 6.5%. In the same harvest period, CP and starch content of Jinling 17 are the highest, Jinling 37 are the lowest. NDF, ADF and ADL content of Fengtian 9 were significantly lower than the other three species (P<0.05).(4) From DM yield and nutritive value of silage corn into considerations, Jinling 17 and Fengtian 9 are better than other varieties under this experimental conditions.