Effects of Leaf Loss by Artificial Defoliation on the Growth of Different Poplar and Willow Varieties

Abstract

The cultivation of fast-growing tree species in short rotation coppices has gained popularity in Germany in recent years. The resilience of these coppices to phyllophagous pest organisms is crucial for their profitable management, since the loss of a single annual increment can lead to uncompensable economic losses. To study the effects of leaf loss on the growth of poplar and willow varieties that are frequently cultivated under local conditions, three sample short rotation coppices including five poplar (Populus spp.) and three willow (Salix spp.) varieties were established in a randomized block design with four artificial defoliation variants and, on one site, with three different variants regarding the number of defoliation treatments. After up to three defoliation treatments within two growing seasons, the results show negative effects of leaf loss on the height growth and the fresh weight of the aboveground biomass of plants. Our data also suggests a lasting effect of defoliation on plant growth and re-growth after the end of the treatment. In general, defoliation had a greater impact on the growth of poplars than on willows. We conclude that even minor leaf loss can have an impact on plant growth but that the actual effects of defoliation clearly depend on the site, tree species, and variety as well as the extent and number of defoliations, which determine the ability of plants for compensatory growth.

The impact of the Asian chestnut gall wasp (Dryocosmus kuriphilus) on chestnut tree growth may be mediated by site resources

“…The present findings are consistent with the continuum of responses hypothesis (Maschinski and Whitham, 1989), which assumes that the probability of compensation for herbivory decreases as competition with neighbors (mainly for light and water) increases and nutrient availability decreases (e.g., Björkman et al, 2000;Guillet and Bergström, 2006;Helbig et al, 2021). As chestnut is considered poorly competitive and light-demanding (Covone and Gratani, 2006;Conedera et al, 2021), the different conditions of competition for light resources may mainly explain the apparently contradictory findings of the present study and of the studies by Mariotti et al (2013) and Marcolin et al (2021).…”

Compensatory Growth and Physiological Protective Mechanisms of Populus talassica Kom. × Populus euphratica Oliv. in Response to Leaf Damage

“…Chl a = (13.95A 665 − 6.88A 649 ) × V W × 1000 (5) Total Chl =Chl a + Chl b (6) Chl b = (24.96A 649 − 7.32A 665 ) × V W × 1000 (7) where A = optical density at 649 and 665 nm, V = final volume (mL), and W = leaf tissue fresh weight (g).…”

“…Studying the ability of plants to recover from mechanical damage is of great significance for their survival. Mechanical damage to woody plants often weakens tree growth, affecting plant growth physiology [3], biomass allocation [4], photosynthetic characteristics [5], and carbon sequestration capacity [6]. In severe cases, it slows lateral root or branch growth, which can even result in tree mortality [7,8].…”

Fast-Growing Trees Species—Opportunities and Risks for Sustainable Agricultural and Forest Land Use Systems

“…The article by Kalita et al focuses on the modeling of soil carbon in Salix plantations [8], while the article by Boruszewski et al reports on potentially suitable areas for the planting of fast-growing tree species in Poland [9]. Zitzmann and Rode [10] examine the impact of short-rotation plantation management on phytodiversity [10], while Helbig et al deal with the influence of leaf feeding on the growth of poplars and willows [11]. Finally, Hernandez-Estrada et al describe the dry matter loss of poplar wood chips during storage [12].…”