Published online by Cambridge University Press: 12 June 2017
Maleic hydrazide (MH) or 1,2–dihydropyridazine–3,6–dione is an organic plant growth regulator which has been found useful in preventing sucker formation in flue-cured tobacco, in preventing sprouting of stored vegetables, and in inhibiting the growth of some weeds and grasses. The compound can be synthesized from hydrazine and maleic acid or by reacting hydrazine hydrate and maleic anhydride. The commercial product, MH–30, is made by reacting MH with diethanolamine (DEA), and contains 58 per cent active ingredient, the remainder being classified as inert ingredients.