What Scientists have learned about plants

Scientists learned that plants mate and have offspring very much as animals do. A male plant and a female plant are both needed to produce a seed from which a new plant will grow. This sug­gested taking one kind of male plant and another kind of female plant and trying to produce new foods that would com­bine the qualities of two other foods. Luther Burbank, an American who made a lifelong study of this, created many new plants. He created new, better-tast- ing fruits by mixing the pollens of two different plants (a process called cross- pollination) and his creations included such things as the honeydew melon and the grapefruit we see most often on our table today.

The same kind of work produced string beans without strings (and most people today have forgotten the time when string beans had such strong, tough and unpleasant strings in them that you could hardly bite through them), and oranges that give much more juice than other oranges, a development that led to the habit of drinking orange juice for breakfast today. Before then, oranges did not have enough juice to make it worthwhile to squeeze them. The science of chemistry was a great help to agriculture. Farmers would dis­cover that certain insects were ruining their plants.

The insects would eat the leaves, or bore into the vegetables or fruits, or even attack the roots and keep the plants from growing. There were poisons that would kill the insects, but those same poisons might kill the plants —or else make the fruit of those plants poisonous to the people who ate them. The problem was to find chemicals that would kill insects without hurting the plant. Chemists have discovered liquids that you can spray or powders that you can dust on many plants that will keep the insects from eating them but will not keep the plants from growing and will not be dangerous to people who eat the vegetables or fruits. Not all the problems have been solved, so the work goes on and every year new ways are found to combat the pests and the dis­eases of our food plants and so to make the crops bigger and healthier.