Abstract
The incidences of overgrowth and unmarketable fruits were compared between tomato autografts planted with 50 mL plug and those with 800 mL pot (control), and the regulation of such incidences were tried with Solanum rootstocks. Planting with plug promoted the early growth of tomato plants and the growth was regulated by Solanum rootstocks. S. melongena rootstock suppressed the overgrowth and kept vigor similarly to that of the control autograft, whereas S. integrifolium and S. torvum rootstocks decreased the growth more than S. melongena. Thickening and aerial rooting at scion base, phenomena of graft incompatibility, were observed in the heterograft on S. torvum. Marketable fruit weight was lower in planting with plug than that with pot in tomato autografts, but unmarketable fruit weight, especially cracking fruits, markedly increased by planting with plug. Among grafts on various rootstock species, marketable fruit weight was the largest in S. melongena rootstock and the smallest in S. torvum rootstock. The marketable fruit weight of the heterograft on S. melongena planted with plug was similar to that of control plants. Planting of the tomato plugs decreases marketable fruit yield through cracking of the fruits. However, such deteriolation is ameliorated by S. melongena rootstock.
