Mobile balers, machines which gather and bale hay in one process, were first developed around 1940. The first balers produced rectangular bales small enough for a person to lift, usually between 70 and 100 pounds (32 and 45 kg) each. The size and shape made it possible for people to pick bales up, stack them on a vehicle for transport to a storage area, then build a haystack by hand.
From Wikipedia, the free encyclopedia. An F1 hybrid (or filial 1 hybrid) is the first filial generation of offspring of distinctly different parental types. F1 hybrids are used in genetics, and in selective breeding, where it may appear as F1 crossbreed. The term is sometimes written with a subscript, as F1 hybrid. The offspring of distinctly different parental types produce a new, uniform phenotype with a combination of characteristics from the parents.
In this example, he crossed a purebred white-flowered pea plant with a purebred purple-flowered pea plant. These plants are the parental, or P, generation. The resulting offspring, called the first filialâor F 1 âgeneration, all had purple flowers. The trait for white flowers seemed to disappear. When Mendel allowed the F 1 generation to self-fertilize, the resulting F 2 generation produced both plants with purple flowers and plants with white flowers. Therefore, the trait for white flowers had not disappeared; it had been hidden, or masked. traits that were hidden when parental purebred flowers were crossed reappeared when the F 1 generation was allowed to self-pollinate.