EFFECTS OF ROOTSTOCK VARIETIES, LEAVES AN D GRAFTING CONDITIONS ON SCION GROWTH IN EGGPLANT

Studies were conducted on the effects of root stock varieties, leaves and size on scion growth and assimilate transport in eggplant. The tra nslocation and distribution of photosynthetic assimilates from root st ock and scion leaves on different stock/scion combinations were determ ined by (CO2)-C-14 pulse feeding method. 1. Different root stock varie ties resulted in a variation of the scion growth response. The scion d ry weight and leaf area were extremely higher in rootstock varieties o f 'Taibyo VF(Solanum integrifolium Poir. x S. melongena L.)' and Scarl et eggplant(S. ingrifolium Pier.: Hiranasu('Akanasu': Takii Seed Ltd)) than in 'Senryo No. 2 (S. melongena L.)'. However, the root weight we re not changed significantly between root stock varieties. 2. The scio n growth was enhanced by increasing the number of root stock leaves fr om 0 to 3. When three leaves were left on the root stock, the scion gr ew vigorously, indicating that these leaves significantly affect growt h. 3. The percentage distribution of C-14-assimilates by the stock lea ves to the scion ranged from 35 similar to 40% on 28 days after grafti ng; about 50% of the assimilates in the root stock came from the scion leaves. 4. The source-sink relationship between the scion leaf and th e roots was analyzed by relative sink strength (RSS) and was found to be unrelated; however, a close relationship was found between the root stock leaves and roots. The relationship between growing parts and bo th scion and stock leaves was strong. The photosynthetic assimilates f rom both scion and root stock leaves were translocated through the gra ft union, the amount is depending on the degree of vascular connection s established.