太阳光是取之不尽,用之不竭的气候资源,不仅农作物生长、发育不可缺少,而且是一切生物赖以生存的能量源泉。春天,人们常常看到,窖里的山药、萝卜生长出细长而白嫩的幼芽,把它移到阳光充沛之处,就可以变成绿色的枝叶;大葱的茎本来是绿色的,经过培土,就变成白色,培土越厚,葱白越长,这些现象,说明农作物的绿颜色是在阳光的照射下形成的。农作物得不到阳光,也就没有绿色。农作物茎叶的绿色,是细胞里含有绿色颗粒而显现出来的。这些绿色 Sunlight is inexhaustible climate resources, not only crop growth, indispensable to development, but also the source of energy for all living things. Spring, people often see, cellar yam, radish grow slender and tender young buds, move it to the sunny place, you can turn into green foliage; green onions stems have been green, after earth , It becomes white, the thicker the soil is, the longer the greenish white. These phenomena indicate that the green color of the crops is formed under the irradiation of sunlight. There is no green crop without sunlight. Crop stems and leaves of green, cells contain green particles appear. These are green