When the ripening gene produces a normal mRNA transcript, the antisense mRNA binds to it, blocking synthesis of the ripening enzyme. Crop plants are being engineered to resist pathogens and pest insects. Some plants have been engineered to resist insect attack, reducing the need to apply chemical insecticides to crops. Have an enhanced food value. For example, corn and wheat might be engineered to produce mixes of amino acids optimal for the human diet.
Gaseous nitrogen is useless to plants.
Nitrogen-fixing bacteria live in the soil or are symbiotic within plant roots. The nitrogen-containing compounds produced by nitrogen fixation are taken up from the soil by plants and used to make organic molecules such as amino acids and nucleotides. A major limiting factor in plant growth and crop yield is availability of useable nitrogen compounds. This is why nitrogenous fertilizers are used in agriculture. Recombinant DNA technology can possibly be used to increase biological nitrogen fixation of bacterial species living in the soil or in association with plants.