Methods for enhanced root nodulation in legumes

A method of increasing, enhancing, or accelerating root nodulation in a legume plant, accelerating growth of nitrogen fixing bacteria in nodules of a legume plant, increasing protein content in a legume plant, increasing yield of a legume plant, improving water retention of a legume plant, or reducing water use of a legume plant, the method comprising:

• applying to the legume plant a composition comprising:
• a yeast preparation component comprising yeast stress proteins resulting from subjecting a mixture obtained from yeast fermentation to stress;
• at least one non-ionic surfactant;
• at least one anionic surfactant;
• and
• water to make 100% volume;
• wherein the yeast preparation component comprising yeast stress proteins is produced by a method comprising:
• growing yeast under aerobic fermentation conditions to obtain a fermentation mixture comprising fermented yeast cells, and proteins and peptides secreted therefrom;
• subjecting the fermentation mixture to stress in order to stimulate the yeast cells to express heat shock proteins to obtain a stressed fermentation mixture;
• separating the stressed fermentation mixture into a solid/precipitate and a supernatant;
• and
• adjusting the pH of the supernatant to produce the yeast preparation component comprising yeast stress proteins.