Prevention of high temperature induced rosette and flowering acceleration of Dwarf Eustoma ‘Little Belle Blue’ by optimum temperature treatment

The objective of this research is to produce dwarf Eustoma grandiflorum (Raf.) Shinn. ‘Little Belle Blue’ potted plants flower in 130 days after sowing without exhibiting high temperature induced (HTI) rosette. High rosette defined as “the abnormal growth and development a compressed stem near the ground forming 3 – 4 pairs true leaves resulting from exposure seedlings temperatures, fail form elongated internodes flower”. effect photoperiod treatments during various stages was tested on accelerated flowering HTI (Expt. 1, 2, 3), induce preventing 4, 5, 6). at 32/27 °C (day/night) 0 30 (0 30D) (32/27 °C/0 30D 27/22 °C/31 60D should be avoided because 39% exhibited 1). Lower temperatures shorter periods (24/22 °C/61 90D, 24/22 60D) prevented 2). treatment 23/21 °C/34 74D considered acceptable when coupled with 21/19 °C/74 115D promote prevent 3). earliest (157 days) suggested that 20-day are 25/23 20D, °C/21 40D, 12/10 80D, °C/81 100D. Early occurred 80D During these periods, it bud initiation might occur, especially pronounced 4). Flowering (148 45-day old seeds January were exposed for (46 75D) long-day (LD) 21/18 5). total cropping time reduced 133 inducing reducing number flowers by following treatments: Sowing late February growing °C/30 50D, either under short-day (SD) or LD/51 70D, LD/71 90D A clear distinction made between physiologically normal vegetative juvenile last about 60 up small occurs predominantly 29/27 74D. an annual does not exhibit seed dormancy since germination 12 14 °C, require vernalization Seeds sown 21/16 °C/51 70D/LD, °C/71 90D/LD, finally °C/91 130D recommended.