Abstract: The germination of seeds is improved by treating the seeds with a solid-form super absorbent polymer that has absorbed water. Super absorbent polymer particles that contain an amount of water such as about 5 to 7 times their weight that is significantly less than the amount of water they are able to absorb such as about 80-120 times their weight and do not substantially adhere to each other are mixed with seeds to form a mixture that may contain a volume ratio of seeds to polymer particles of 0.2 to 5:1. The mixture is stirred while supplying air or gaseous oxygen into the mixture for a time and at a temperature sufficient to cause the seeds to imbibe sufficient water to enhance their vigor for sprouting, but insufficient to cause sprouting. The mixture is sieved to obtain seeds having essentially no adhering polymer residue of the particles, after which the seeds may be dried. The polymer particles may be spherical, and before absorbing water have a size of 50 to 300 .mu.m.

Abstract: Grafting a scion on a stock is effected by opening a chuck and inserting bar-like members in a storage chamber successively into the chuck with the front end of such bar-like members protruding out of a front end hole 5D, 105D, closing the chuck 4, 104 to thereby hold the bar-like member 2, inserting the front end of the protruding bar-like member 2 into a graft joint end of the stock, separating the grafting device from the bar-like member, and inserting the other end of the bar-like member into a graft joint end of the scion so as to abut the graft joint ends of the stock and scion against each other. The bar-like member can be simply and rapidly inserted into the stock, so that abutment between the stock and scion can be effected with extreme ease.