玉米植株营养含量及变化规律研究

Studjes on the Content and Change Lawsof Nutrients in Corn Plant

测定了春玉米植株不同生长期及成熟期各结构部位的营养含量变化。结果表明：玉米雄穗在花蕾期、初花期、盛花期和末花期粗蛋白含量分别为１２．５３％、１１．０３％、１０．４５％和８．９５％；籽实成熟期为４．２４％。叶片：全绿叶、１／３黄叶、２／３黄叶和全黄叶的粗蛋白含量分别为１０．９６％、５．７０％、３．４２％和２．５５％。植株粗脂肪、无氮浸出物含量随植物的成熟递减，而粗纤维、粗灰分同时随之递增。玉米植株从生长期至成熟期其营养含量从高到低依次大致为雄穗、叶片、茎、秆和苞叶。产量以茎秆最多，叶片次之，雄穗最少。因此，在不影响玉米籽实产量的前提下，尽可能地早期收割利用玉米雄穗、叶片、茎秆，对提高玉米秸秆的生物价值及经济效益有重要意义。

Corn plant contains crude protein、 crude fat、 minerals、 carotene and chlorophyll.The study deiermine thenutrient conients of the different parts of ihe spring corn in variousgrowth and maturity pericds. The results show that the crude protein contents are 12. 53%,ll. 03% , 10. 45% and 8. 95% in the periods of flower bud, primary flower, flower flourishingand flower declining respectively. The crude protein content of the mature seed is 4. 24%. To theleaf blade, ihe crude proiein contents are 10. 96% , 5. 7% , 3. 42% and 2. 55% in the whole greenleaf. 1/3 yellow leaf , 2/3 yellow leaf and the whole yellow leafrespectively. The variation laws ofcontents of crude fat and N-free extract is all decrease with the maturity of plants , but the crudefibre and crude ash is increase progressively. The nutrient contents of corn plant decrease progres-sively from ihe growth period to the maturity period ,which basic order is niale tassel , leaf blade ,straw and bud leaf. The straw has the highest output ,followed by leaf blade. The male tassel haslowest output. Thus ,under the prerequisite of no affecting output of corn seeds , the male tassel,leaf blade and straw should be harvested and used as early as possible, which has an importantsignificance for raising the biological values and economic benefit.