Seedling emergence and growth of pawpaw (Carica papaya) grown under different coloured shade polyethylene.

摘要

Seven nursery shades made of blue, yellow, green, red, and colourless polyethylene, and palm frond (Elaeis guineensis Jacq) and non-shaded frame were evaluated for their effects on seedling emergence and early growth of two fruit morphotypes of 'Sunrise Solo' pawpaw cultivar. Seedlings grown under different polyethylene colours showed significant (P<0.05) effect on days to 50% seedling emergence, percentage emergence at first emergence, and percentage weekly emergence for the first six weeks after planting. The highest percentage emergence (72%) was observed under green shade colour compared to palm frond and non-shaded seedlings that gave 63 and 60%, respectively. Also, leaf-count, plant height, stem girth and vigour - monitored for five months in the nursery and field - were responsive to different colours used as nursery shade. Plant height, stem girth, and vigour were higher in seedlings grown under green polyethylene shade. Comparison of fresh weight of root, stem, leaf and total dry matter yield of seedlings grown under different nursery shades showed that seedlings grown under green shade gave the best result. Temperature and light intensity varied significantly (P<0.05) under the different nursery shades, and these differences in microclimate are implicated for the variability in seedling emergence and growth pattern. Evidence from the study revealed that green polyethylene used as nursery shade enhanced seedling emergence and growth quality of the test crops compared to other colours of polyethylene and palm fronds..