Soil Temperature and Precipitation Affect the Rooting Ability of Dormant Hardwood Cuttings of Populus

Abstract

In addition to genetic control, responses to environmental stimuli affect the success of rooting. Our objectives were to: 1) assess the variation in rooting ability among 21 Populus clones grown under varying soil temperatures and amounts of precipitation and 2) identify combinations of soil temperature and precipitation that promote rooting. The clones belonged to five genomic groups ([P. trichocarpa Torr. & Gray x P. deltoides Bartr. ex Marsh] x P. deltoides ‘BC’; P. deltoides ‘D’; P. deltoides x P. maximowiczii A. Henry ‘DM’; P. deltoides x P. nigra L. ‘DN’; P. nigra x P. maximowiczii ‘NM’). Cuttings, 20 cm long, were planted in Iowa and Minnesota, USA, in randomized complete blocks at 1.2- x 2.4-m spacing across three planting dates during 2001 and 2002. Soil temperatures were converted to belowground growing degree days (GDD) (base temperature = 10°C) accumulated over 14 days. Genomic groups responded similarly for root dry weight, number of roots, total root length, and mean root length, that increased as belowground GDD increased. Belowground GDD and precipitation governed rooting throughout the 14-d growing period. A minimum of four days above 14°C, along with sufficiently dispersed precipitation (e.g. no more than 3 d without a precipitation event), were needed to sustain aboveaverage rooting. Therefore, we recommend using a base temperature of 14°C for future models estimating belowground GDD in northern temperate zones.

Effect of defoliation intensity and timing on the growth of Populus alba and Salix babylonica x Salix alba

“…and Populus spp. have genetic and morphological distinctness (Karrenberg et al 2002, Zalesny et al 2005; also ecological differences emerge in studies comparing genus, species or hybrids in traits as tolerance to damage (Nordman et al 2005, Powers et al 2006, growth strategies adopted throughout the season (Tharakan et al 2005), root development (McIvor et al 2013), suitability for phytoremediation purposes (Dos Santos et al 2007, Borghi et al 2008 or suitability for short rotation coppice (Laureysens et al 2005, Tharakan et al 2005. Thus, this versatility in plant characteristics of poplars and willows would explain the differences in responses to defoliation observed in our study.…”

Evaluation of Early Rooting Traits of Eastern Cottonwood That Are Important For Selection Tests

“…On one side are genetic sources of variation (MELCHIOR and HATTEMER, 1966;WILCOX and FARMER, 1968;YING and BAGLEY, 1979;GUZINA, 1987, HAN et al, 1994KOVACEVIC et al, 2005) and differences among cuttings within genotype, known as C -effect (SMITH and WAREING, 1972;YING and BAGLEY, 1977;LI et al, 1998). There are also factors of the environment such as: soil texture (WILCOX and FARMER, 1968), temperature and precipitation (ZALESNY et al, 2005), microrelief (ALKINANI, 1972), storing conditions (NANDA and ANAND, 1970;FEGE, 1984) and nursery technology (FEGE, 1983). …”

“…EX MARSH) particularly, could still compromise nursery production and the establishment of short rotation plantations for the production of biomass, as well. That is why modern poplar breeding programs regularly evaluate rooting ability of hardwood cuttings and its survival (TESSIER DU CROSS, 1984;GUZINA, 1987;HAN et al, 1994;ZALESNY et al, 2005).…”

Evaluation ofPopulusandSalixContinuously Irrigated with Landfill Leachate II. Soils and Early Tree Development

“…First, DN Populus clones performed similarly when irrigated with leachate or water. Recently, researchers have reported below-average growth performance (i.e., rooting, diameter, and height) of traditional DN genotypes such as clones DN34 and DN182 (Riemenschneider et al, 2001;Zalesny and Wiese, 2006;Zalesny et al, 2005a), which has led to the consideration of less deployment of these DN clones, especially in the North Central United States. However, the results of the current study were important because, along with phytoremediation capabilities (Zalesny and Bauer, 2007) and promising results from recent breeding efforts (Neil Nelson, USFS NCRS, William Berguson, University of Minnesota NRRI, personal communication) DN clones appear to be suitable genotypes for the cleanup of leachate with similar contaminant levels and, possibly, of other contaminants.…”