Physical properties and seed quality after pelleting with different binder and filler materials of lettuce seed (Lactuca sativa L.)

Abstract

Lettuce seeds are small, flat shapes and less food accumulated in the seed. Seed pelleting as a way to raise the quality of the seed that suitable for planting. Binder and filler materials are key elements to make seed pelleting successfully. The objective of this research was to find types of suitable binder and filler materials for pelleting of lettuce seeds. The experiment was conducted at the Seed technology laboratory, Seed Processing Plant, Faculty of Agriculture and Pharmaceutical technology laboratory, Faculty of Pharmacy, Khon Kaen University. This experiment consisted of two parts. The first part was the study on four binder materials for seed pelleting including methyhydroxy ethylcellulose (MHEC), hydroxylpropyl methylcellulose (HPMC), polyvinyl pyrrolidone (PVP-K90) and polyvinyl alcohol (PVA). Calcium sulphate of 250 g was used as a filler per 10 g of lettuce seed. The second part was the study on six filler materials including talcum, calcium carbonate, calcium sulfate, calcium carbonate with pumice, calcium carbonate with bentonite and calcium carbonate with zeolite. Methylhydroxy ethylcellulose 0.5% (w/w) was used as a binder per 10 g of lettuce seed. Physical quality of pelleted seeds were subsequently tested. The results indicated that the pelleted seeds of lettuce with MHEC and calcium sulfate could be formed easily. The pelleted seeds had low friability than the other methods, but it was dissolved in water very well. The pelleted seeds with MHEC and calcium sulfate had not affect on germination and speed of germination. In addition, it also found that the seedling of pelleted seeds has longer roots length than the unpelleted seeds