1Crop Research Division, DSIR, Lincoln, New Zealand.
2Riwaka Research Station, DSIR, Riwaka, New Zealand.
*Paper presented to the International Seminar on Approaches towards Increasing potato production in Developing Countries, C.P.R.S. Jullundur, India, November, 20–23, 1978.
Potato crops grown from vegetative seed suffer from a number of serious limitations, notably, the vulnerability of the seed crop to seed-transmitted diseases. Seed, tubers loose physiological vigour if stored poorly or for long and are slow to multiply. The cost of distributing seed potatoes is also extensive. In many potato growing countries the cost of the vegetative seed exceeds 50% of the total crop inputs. This is major constraint to the rapid increase in potato cultivation.
The technique for raising plants in the field from true potato seed (TPS) was investigated further and compared with TPS transplants. Transplants were more advanced than direct sown seedlings, resulting in higher total yields of table grade tuber. F, TPS seedling matured earlier, averaged greater total and table grade yeilds and showed greater within line variation than seedlings raised from selfed seed.
Qualitatively there was no appreciable difference in flavour between tuber of different lines. Within line variation for specific gravity was high in some lines. Although suffering mainly from late blight (Phytophthora infestans), and a high incidence of leaf roll infection. 73% of the plants of C 1334 produced total yields exceeding 1 kg/plant. The problems and potential of growing genetically mixed lines of TPS are discussed and further possibilities of increasing yield are considered.
