<Li> Polyamines--are strongly basic molecules with low molecular weight that have been found in all organisms studied thus far . They are essential for plant growth and development and affect the process of mitosis and meiosis . </Li> <Li> Nitric oxide (NO)--serves as signal in hormonal and defense responses (e.g. stomatal closure, root development, germination, nitrogen fixation, cell death, stress response). NO can be produced by a yet undefined NO synthase, a special type of nitrite reductase, nitrate reductase, mitochondrial cytochrome c oxidase or non enzymatic processes and regulate plant cell organelle functions (e.g. ATP synthesis in chloroplasts and mitochondria). </Li> <Li> Strigolactones - implicated in the inhibition of shoot branching . </Li> <Li> Karrikins - not plant hormones because they are not made by plants, but are a group of plant growth regulators found in the smoke of burning plant material that have the ability to stimulate the germination of seeds </Li>

Hormones that stimulate seed germination and plant growth