Variability and relationships among rooting characteristics for white poplar hardwood cuttings

Abstract

White poplar is a key species in wood production and afforestation, but also very important for biodiversity preservation and habitat improvement. Vegetative propagation from hardwood cuttings is the most desirable method of white poplar breeding. The present research analyzed the effect of various technological treatments on four white poplar clones. Selected treatments were powder formulations of indole butyric acid (IBA) and foliar treatment with urea. The variability of 14 morphometric characteristics on the rooting of cuttings was analyzed, as well as relationships between them. Differences in analyzed morphometric characteristics depended on genotype, while the effect of the examined technological treatments was detected only by Fisher's least significant difference (LSD) test. Significant variability between genotypes was found for traits describing rooting at the basal cut (R0 and R0p), the number of leaves (LN), the total number of roots (TRN), and cutting survival in the first part of the growing season (SURV07). Application of IBA had significant stimulating effects on rooting at the lower part of cuttings (R05) compared to controls. Variability between genotypes after foliar treatment with urea was not detected. The examined parameters were grouped into 5 groups by principal component analysis, where shoot traits and traits that describe rooting at the basal cut were in the same group with total number of roots, and cutting survival (SURV07) was in a separate group. These results suggest a need for further testing of the characteristics of hardwood cuttings in white poplars. More efficient clone technology is needed, using auxins and/or nitrogen fertilization designed to suit the specific requirements of particular clones.

Establishment of white poplar clonal plantations by stools

“…Bela topola, pogotovo selekcionisani klonovi, ima niz značajnih uzgojnih karakteristika koje je ističu kao proizvodnu drvenastu vrstu: brz rast, toleranciju prema mnogim abiotičkim i biotičkim agensima, izdanačku moć panja i korena, i dr. Međutim, jedan od najznačajnih faktora koji ograničavaju širenje površina pod belom topolom je slab potencijal za ožiljavanje zrelih reznica, koji karakteriše čitavu sekciju Populus (ranije Leuce) roda Populus. U tom smislu, i pored stalnih napora na unapređenju rasadničke tehnologije topola, rasadnička proizvodnja bele topole je poseban izazov (Kovačević et al 2014;Kovačević i Igić, 2018;Nonić et al 2019;Igić et al 2020;Kovačević et al 2020). Danas se za zasnivanje klonskih plantaža bele topole uglavnom koriste ožiljenice tipa 1/1, 1/2 i 2/2, koje se sade normalnom (plitkom) sadnjom na 0.8 -1.2 m dubine.…”

Survival and growth of white poplar rooted cuttings regarding term of planting

“…The main effort is directed to activation of pre-formed primordia which is crucial step in early phases of the formation of root system and further cuttings' survival (Smith and Wareing, 1972;Kovacevic et al 2009;Zhao et al 2014). In spite wellknown importance of auxins in control of cuttings' rooting (Pacurar et al 2014), results of Kovačević et al (2014) and Igić et al (2020) suggest that effects of rooting stimulation with indolbutiric acid is considerably dependent on clones and soil properties.…”

“…There is constant need to improve poplar nursery technology in general and to adjust it to the specificities of interesting genotypes, which is especially challenging in case of white poplar (Kovačević et al 2002;Kovacevic et al 2008a; Kovačević et al 2014; Kovačević and Igić, 2018;Nonić et al 2019;Igić et al 2020). The main effort is directed to activation of pre-formed primordia which is crucial step in early phases of the formation of root system and further cuttings' survival (Smith and Wareing, 1972;Kovacevic et al 2009;Zhao et al 2014).…”