Establishment and Growth of Potato Micro-Cuttings in Sand Trays

摘要

Two separate experiments were conducted to evaluate the success of the establishment and growth of micro-cuttings of potato (5 - 6 cm tall) in sand trays [38 cm (L) × 28 cm (W) × 7.5 cm (H) plastic trays] under controlled environment (22?C ± 2?C, 60 - 75 μmosm–1?s–1 light energy for 16 h daily). In the first experiment, micro-cuttings of potato cv. Diamant were planted at six populations (500, 600, 700, 800, 900 and 1000 cuttings per tray) in treated sand (sun dry, 1% formaldehyde, 0.2% Dithane M-45 and control). The mortality percentage of micro-cuttings was nil for sun dry sand while formaldehyde and dithane M-45 treated sand had 1% - 4% against 15% in the control with the highest population density. Mortality of micro-cuttings in formaldehyde and dithane M-45 treated sand trays were found not to be related to pathogenic organism rather toxic effect of these two chemicals. Micro-cuttings in Sun dry and control treatments showed better growth performance than these in chemically treated sand trays. In the second experiment, urea @ 1, 2 and 3 g per tray was applied as solid form after 15 days of planting the micro-cuttings and as liquid form @ 0.5, 1 and 2% solution sprayed in the micro-cuttings repeatedly after 15, 30, 45 and 60 days of planting. The micro-cuttings which received urea as solid state died within 2 - 3 days and 2% urea solution was also detrimental. Urea solution @ 0.5% found to be very effective for vegetative growth of micro-cuttings in sand trays. The control was also good for vegetative growth but at a slower rate.