Growth and physiology of aspen supplied with different fertilizer addition rates

Abstract

Isebrands, J. G. 1998. Growth and physiology of aspen supplied with different fertilizer addition rates. -Physiol. Plant. 103: 513-526.Variable internal plant nutrient content may confound plant response to environmental stress. Plant nutrient content may be controlled with relative addition rate techniques in solution culture. However, because raising large numbers of plants in flowing solution culture is difficult. we investieated the feasibihtv of raisine slants in soil rnk using relative fertilizer additions. Asp& (Populus tremubides Michi.) clones (216, 259 and 271) planted in pots containing a peat, sand and vermiculite (2:1:1, v/v/v) soil mix were grown with exponentially increasing fertilizer concentrations and harvested periodically to assess growth. Addition rate treatments ranged from 0.01 to 0.05 day-'. The lag phase of growth, in which plants adjusted to the fertilizer regime, lasted 40 days after-which piants entered the-experimental period characterized by constant relative growth rates equivalent to applied fertilizer addition rates. Total plant nutrient concentration was (1) unique for each addition rate, (2) linearly related to addition rate and growth rate, and (3) tended to increase at the highest, and decrease at the lowest addition rates. Regardless, the plants appeared to have attained steady-state conditions. Allocation of carbon to roots increased with lower addition rate treatments and was not denendent unon ontoeenv. There were no treatment differences in growth response among aspen clones. Yet there were treatment differences in leaf chlorophyll and photosynthesis within the clones. For the 0.05 dav-' addition rate treatment. chloronhvll. leaf N concentration and photosynthefic rate were strongly correlated with ohe'another, were at a maximum in recently mature leaves, and rapidly declined with leaf age. The rate of decline in these leaf characteristics was slowest in clone 271, consistent with the leaf longevity stress response reported elsewhere. Plant responses from these relative fertilizer addition trials in soil mix agree closely with those run in hydroponics, indicating that steady-state nutrition can be achieved with a technically simple experimental assemblage.

Growth, allocation and leaf gas exchanges of hybrid poplar plants in their establishment phase on previously forested sites: effect of different vegetation management techniques

“…3c). In agreement with Coleman et al [11] we think that the measurements obtained with the SPAD meter can be a useful technique to rapid estimate leaf N concentration and A max in poplar plantations.…”

Growth, physiology, and nutrient retranslocation in nitrogen-15 fertilized Quercus rubra seedlings

“…A similar strong linear relationship was also reported between SPAD reading, leaf N concentration, and photosynthetic capacity in aspen (Populus tremuloides Michx.) [11]. This suggests that the SPAD meter holds promise for rapid and non-destructive assessment of foliar N, which can help to effectively monitor seedling nutritional status.…”

“…Conventional wet-chemistry techniques exist for assessing plant N status, which involves destructive sampling of plant materials [11,47]. These techniques are relatively expensive and laborious and therefore, not suitable for rapid appraisal of plant N status throughout the growing season.…”

Forest production responses to irrigation and fertilization are not explained by shifts in allocation

“…Therefore, we conclude that biomass accumulation does not favor shoots in developmentally equivalent stands grown with more favorable soil resources. Other attempts to compare developmentally equivalent stands also demonstrate that resource availability has little or no effect on relative belowground biomass accumulation in herbaceous plants (McConnaughay and Coleman, 1999), tree seedlings (Coleman et al, 1998;Drew and Ledig, 1980;Gebauer et al, 1996), or tree stands (Coleman et al, 2004a;King et al, 1999).…”