Effects of planting material source, age and GA3 on growth and yield of aeroponically grown potatoes

A good quality planting material for a highly productive minituber production in aeroponic systems is important. This study was conducted to determine if the age and source of the planting materials used in the aeroponic beds would influence tuber productivity. Repeated harvesting of unrooted apical cuttings from hydroponic plants would substantially reduce cost of the planting material by more than 50%. Four different planting materials were evaluated in two experiments in each of two seasons: 28 day old in vitro plants; 28 day old in vitro plants place in a hydroponic system for 14 days; unrooted apical cuttings taken from 42 and 56 day old hydroponic plants. These were evaluated using three cultivars (cvs) in an aeroponic system in the spring season and autumn seasons in a semi tropical setting in Sichuan. All four sources of planting material had 'juvenile' simple rounded leaves when transplanted to aeroponic beds. Whole hydroponic plants had the head start compared to in vitro plants and out yielded in vitro plants in the spring season for cv Mira and Chuanyu 117. Apical cuttings for cv Favorita and Chuanyu 117 from hydroponically grown mother plants rooted in four to seven days grew vigorously and yielded higher tuber weight compared to the younger whole hydroponically sourced plants during the spring season. Autumn season results had generally lower yields and no statistically significant differences observed between the four types of planting material. There was a positive correlation between mid season stolon number and final tuber number. The most economical and productive planting material are the 1st and 2nd unrooted apical cuttings taken from hydroponically grown mother plants.