Because it is cold-intolerant, in theÃÂ temperate zonesÃÂ maize must be planted in the spring. ItsÃÂ root systemÃÂ is generally shallow, so the plant is dependent on soil moisture. As a plant that usesÃÂ C4 carbon fixation, maize is a considerably more water-efficient crop than plants that useÃÂ C3 carbon fixationÃÂ such asÃÂ alfalfaÃÂ andÃÂ soybeans. Maize is most sensitive to drought at the time of silk emergence, when the flowers are ready for pollination. In the United States, a good harvest was traditionally predicted if the maize was & x22;knee-high by theÃÂ Fourth of July& x22;, although modernÃÂ hybridsÃÂ generally exceed this growth rate. Maize used forÃÂ silageÃÂ is harvested while the plant is green and the fruit immature. Sweet corn is harvested in the & x22;milk stage& x22;, after pollination but before starch has formed, between late summer and early to mid-autumn.
圖片編號:
125571674
拍攝者:
Sarfrazalii
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標準授權 | 360 x 480 px | JPG | 13 點 |
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進階授權 | 6240 x 8320 px | JPG | 88 點 |
進階授權 | 6240 x 8320 px | JPG | 88 點 |