Influence of environment, fertilizer and genotype on shoot morphology and subsequent rooting of birch cuttings

Abstract

Differences in rooting ability of birch (Betula pubescens J.F. Ehrh.) cuttings were observed as a result of differences in genotype and physiology of the stock plants. The uniformity in response among cuttings from micropropagated plants compared with cuttings from seed plants confirmed the advantage of using micropropagated plants to study environmental effects. Shoot morphology of the seed stock plants was influenced by both photoperiod and thermoperiod. A day/night temperature of 15/25 degrees C reduced stem elongation compared with a day/night temperature of 25/15 degrees C regardless of photoperiod, and a continuous light regime resulted in more shoots per plant in both temperature regimes than a 16-h photoperiod. A reduction in the supply of macronutrients did not influence shoot morphology, but increased rooting substantially and seemed to override the effects of environmental factors. In cuttings of seed plants, the highest rooting percentage and number of roots were obtained in a 16-h photoperiod with a day/night temperature of 15/25 degrees C. In micropropagated stock plants, there was a positive correlation between shoot length and number of leaves per shoot and topographical distribution of light within the plants, but there was no correlation between these parameters and rooting ability of the cuttings. A rooting temperature of 16 degrees C delayed the rate of root production compared with the rate at higher temperatures, but the final rooting percentage was the same over the range from 16 to 28 degrees C. Root branching increased with temperature. At all temperatures, there was a large increase in sucrose content at the base of the cuttings during rooting, whereas the concentration of nontranslocated sugars remained constant. The carbohydrate content at the base of cuttings from micropropagated stock plants was three times higher than at the base of cuttings from seed stock plants, but the higher carbohydrate content was not correlated with a higher rooting potential.

Micropropagation of Hagenia abyssinica: a multipurpose tree

“…Different levels of irradiance affected the growth of in vitro raised plants. The plants under high irradiance had shorter stems and leaves contrary to the results of Welander (1994) where there was a positive relationship between shoot length and light intensity of micropropagated birch (Betula pubescens). The irradiance level and leaf length were also negatively related.…”

“…among genotypes as has been found for other species (Welander, 1994). Different levels of irradiance affected the growth of in vitro raised plants.…”

Mineral Nutrient and Carbohydrate Status of Loblolly Pine during Mist Propagation as Influenced by Stock Plant Nitrogen Fertility

“…Carbohydrate content of stem cuttings during rooting has been studied for several species, but whether or not carbohydrates directly influence adventitious root formation is still unclear (Haissig, 1986(Haissig, , 1989Veierskov, 1988). Furthermore, various mineral nutrients are required for root growth and development (Blazich, 1988) and can influence rooting (Henry et al, 1992;Welander, 1995).…”

Development of a sequence characterized amplified region (SCAR) marker associated with high rooting ability in Larix

“…Differences in rooting ability of cuttings have been shown to be dependent on the genotype and physiological status of the stock plants in many tree species (Radosta et al 1994, Welander 1995, Hoad and Leakey 1996. Selection for good-rooting larch clones seems to be possible, for a number of studies reporting rooting ability to be under strong genetic control in larch (Farmer et al 1992, Yang and Shen 2002.…”