十个玉米品种在广州种植和青贮的潜力研究

为筛选适宜在广州种植的青贮玉米品种,采用随机区组设计种植和袋装青贮的方法,研究了10个玉米品种(京科青贮301、农大108、赣单2、大丰3、宜黄单4、雅玉8、先玉335、郑单958、雅玉26、华玉8)的种植和青贮潜力。结果表明,1)品种间全株干物质产量(P<0.05)和消化率(P<0.01)差异显著,参试品种均超过对照品种华玉8,其中雅玉8的干物质产量最大,达14.30 t/hm²;京科青贮301干物质消化率最高,达78.15%。品种间的相对饲用价值呈现显著差异(P<0.05),京科青贮301的相对饲用价值为123.52,比对照高17.90%(P<0.05),郑单958、赣单2、先玉335、雅玉8、农大108不同程度地高于对照。2)品种间的干物质、粗灰分和无氮浸出物含量差异显著(P<0.05),各品种干物质含量比对照均有不同程度的提高,雅玉26、大丰3、雅玉8干物质含量均达到40%;雅玉26、大丰3、农大108和雅玉8的无氮浸出物含量较高,分别达到65.31% DM、63.94% DM、63.38% DM和62.17% DM。品种间的粗蛋白、粗脂肪和粗纤维含量均无显著差异(P>0.05)。3)玉米品种间植株附着的乳酸菌和霉菌差异显著(P<0.05),郑单958的乳酸菌数达10⁶ cfu/g FM,高于其他品种。4)各玉米品种青贮后的pH值、乳酸和丙酸含量差异显著(P<0.05),对照华玉8的pH值最低为3.63,雅玉8的pH值最高,达4.22;对照华玉8的乳酸含量最高,达9.16% DM。丁酸含量差异不显著(P>0.05),但雅玉8和郑单958没有检测到。各品种青贮的NH₃-N/TN含量差异极显著(P<0.01),雅玉8、郑单958和大丰3分别为8.81%、10.04%和10.61%,至少比对照低13.39%。综合各品种全株干物质产量、营养价值和青贮效果,雅玉8在广州地区种植作青贮饲料利用更有潜力。

Comparison of ten corn varieties as silage material in Guangzhou

In order to select the best corn variety for silage material,ten candidates have been studied:Jingke Silage 301,Nongda 108,Gandan 2,Dafeng 3,Yihuang Dan 4,Yayu 8,Xianyu 335,Zhengdan 958,Yayu 26 and Huayu 8 (control).The corn was planted in the Zengcheng Experimental Field of South China Agricultural University and their dry matter yield,nutrient composition and silage fermentation quality were evaluated at the dough stage.Results were as follows:1) There were significant differences in dry matter yield (P＜0.05)and digestibility (P＜0.01) among the varieties.All the tested varieties scored higher than the control (Huayu 8),with Yayu 8 having the highest dry matter yield (14.30 t/ha) and Jingke Silage 301 the highest dry matter digestibility (78.15℃).The relative feeding value (RFV) of the varieties showed significant differences (P＜0.05).The RFV of Jingke Silage 301 was 123.52,17.90％ higher than the control (P＜0.05),while the scores for Zhengdan 958,Gandan 2,Xianyu 335,Yayu 8 and Nongda 108 were higher than the control.2) The dry matter (DM),crude ash and nitrogen-free extract (NFE) contents also presented significant differences (P＜0.05).The DM contents of the tested varieties were higher than the control,with Yayu 26,Dafeng 3,and Yayu 8 up to 40％ higher.Yayu 26,Dafeng 3,Nongda 108 and Yayu 8 had higher NFE contents than the control (65.31％,63.94％,63.38％ and 62.17％ respectively).There were no significant differences between the varieties for crude protein,crude fat and crude fiber contents (P＞0.05).3) The amounts of lactic acid bacteria and fungi on plants were significantly different among the varieties (P＜0.05).Lactic acid bacteria on Zhengdan 958 exceeded 106 cfu/g of fresh matter (FM),higher than the other varieties.4) There were significant differences in silage pH values,lactic acid and propionic acid contents among the varieties (P＜0.05).Huayu 8 (control) had the lowest pH value (3.63) and the highest content of lactic acid (9.16％ DM),while Yayu 8 had the highest pH value (4.22).There were no significant differences in butyric acid content between the varieties (P＞0.05).Butyric acid was not detected in the silage of Zhengdan 958 and Yayu 8.NH3-N contents were significantly different among the varieties P＜0.01),with Yayu 8,Zhengdan 958 and Dafeng 38.81％,10.04％ and 10.61％ lower than the control.Based upon yield,nutrition composition and silage fermentation quality,Yayu 8 is the best variety for planting in the Guangzhou area as an ensiling material.