Mengxu Su¹, Zhanjiang Han^1,*, Zhen Zhao², Xiaofeng Wu¹, Jiaju Wu¹

Phyton-International Journal of Experimental Botany, Vol.93, No.7, pp. 1689-1703, 2024, DOI:10.32604/phyton.2024.052814 - 30 July 2024

Abstract Leaves are important ‘source’ organs that synthesize organic matter, providing carbon sources for plant growth. Here, we used Populus talassica × Populus euphratica, the dominant species in ecological and timber forests, to simulate carbon limitation through artificial 25%, 50%, and 75% defoliation treatments and explore the effects on root, stem, and leaf morphology, biomass accumulation, and carbon allocation strategies. At the 60th d after treatment, under 25% defoliation treatment, the plant height, specific leaf weight, root surface area and volume, and concentrations of non-structural carbohydrates in stem and root were significantly increased by 9.13%, 20.00%, 16.60%,… More >

Song Y¹, CA. Busso⁵, Y Yu², P Wang³, Wuyunna¹, D Zhou⁴

Phyton-International Journal of Experimental Botany, Vol.87, pp. 242-251, 2018, DOI:10.32604/phyton.2018.87.242

Abstract The effects of different defoliation intensities and frequencies were studied on regrowth and herbage mass of Leymus chinensis and Hordeum brevisubulatum in northeast China for two years. Plants were defoliated to 6, 8 or 10 cm stubble height by removing about 40% of growth down to each designated defoliation height. In the first year, L. chinensis was defoliated 22, 17 or 13 times, and in the second year was defoliated 21, 15 or 15 times to reach 6, 8 or 10 cm stubble height treatments, respectively. H. brevisubulatum was defoliated 26, 21 or 15 times in the first year,… More >

Ithurrart LS^1,2, CA Busso^1,2, YA Torres^1,3, DV Peláez^1,2,3, H Giorgetti⁴, G Rodríguez⁴, ML Ambrosino^2,5

Phyton-International Journal of Experimental Botany, Vol.87, pp. 51-59, 2018, DOI:10.32604/phyton.2018.87.051

Abstract Plant competition for soil resources is common in semiarid rangelands. Plants have various, alternative mechanisms to deal with soil resource acquisition. They include (1) length, weight and proliferation of roots, (2) root length density, and (3) root colonization by arbuscular mycorrhiza. In rangelands of Argentina, plants are exposed to herbivory after natural fires. As a result, knowledge on how these disturbances impact root traits is important for outlining guidelines focused on rangeland management and improvement. Our aim was to analyze the effects of defoliation after a controlled burning on root traits (1) to (3) on… More >

Ferri CM, VV Jouve, AM Sáenz

Phyton-International Journal of Experimental Botany, Vol.86, pp. 190-198, 2017, DOI:10.32604/phyton.2017.86.190

Abstract The defoliation frequency determines above and below ground biomass accumulation, pasture structure and nutritive value. Two defoliation experiments with Panicum coloratum were performed, from September to March. One of them was conducted in pots under greenhouse conditions, and the other one in field plots for three growing seasons (EC) at the Faculty of Agronomy, La Pampa, Argentina (36˚ 46' S; 64˚ 16' W). Defoliation frequency treatments were four cutting intervals (IC; 3, 4, 6 and 8 weeks). In greenhouse experiment, live leaf blade accumulation rates (TAL), tiller appearance (TAM) and death (TMM) rates, live leaf blade… More >

Siliquini OA¹, GA Orioli², JC Lobartini²

Phyton-International Journal of Experimental Botany, Vol.84, No.2, pp. 338-344, 2015, DOI:10.32604/phyton.2015.84.338

Abstract Onion (Allium cepa) is an important horticulture crop because of its value as a food with a long shelf life being a relatively non-perishable product. It is very helpful to understand the growth response of the seeded onion crop to conduct appropriate field practices in attaining the highest or optimum yields. A three year field experiment was conducted using a variety of onion Valcatorce INTA, in a randomized block design with five replicates. Treatments were two plant densities and three rates of N application. The bulb growth followed a classical sigmoid curve. During the rapid growing More >

Ferrante D^1,2, A Cesa^1,2, S Lewis², G Jaurena³

Phyton-International Journal of Experimental Botany, Vol.83, pp. 127-131, 2014, DOI:10.32604/phyton.2014.83.127

Abstract In plants, compensatory growth takes place when the positive effects of defoliation compensate the negative ones, and defoliated plants show a similar or increased production in relation to non-defoliated plants. Our objective was to evaluate the ability to compensate defoliation of Poa spiciformis, a forage perennial tussock grass in southern Patagonia (Argentina). The experiment was performed in potted plants that grew under controlled conditions of watering and fertilization. Three defoliation frequencies were imposed (zero, three or five) using 20-25 day intervals among them. Harvest intensity was always equivalent to 50% of the aerial biomass. Fifteen plants… More >

Gittins¹ C, CA Busso², G Becker¹, L Ghermandi³, G Siffredi¹

Phyton-International Journal of Experimental Botany, Vol.79, pp. 55-68, 2010, DOI:10.32604/phyton.2010.79.055

Abstract Poa ligularis is an important forage in Patagonian rangelands. Populations of this perennial bunchgrass have been severely affected by overgrazing. We propose that increased defoliation frequencies will decrease (1) aerial- and belowground dry matter production, (2) root survival, and (3) concentration and content of total non-structural crown + root carbohydrates, and (4) increase root mortality. Five defoliation frequencies (plus 1 control) were applied in a representative grassland of the Occidental District in Patagonia during two consecutive growing seasons. All four hypotheses were rejected. Aerial and belowground dry matter production increased from one to two or three… More >

Peláez¹ DV, RM Bóo², MD Mayor³, OR Elia⁴, SA Martínez⁵

Phyton-International Journal of Experimental Botany, Vol.78, pp. 17-24, 2009, DOI:10.32604/phyton.2009.78.017

Abstract Plant growth in semiarid rangelands may be affected by time grazing is excluded during the post-fire regeneration period. The objective of this field work was to study the effect of post-fire defoliation at different phenological stages [vegetative (early-season defoliation) and internode elongation (late-season defoliation)] on growth of Piptochaetium napostaense and Poa ligularis, two very important perennial native grasses in the temperate semi-arid region of central Argentina (Caldenal). In general, the post-fire defoliation treatments did not affect the number of green leaves on tillers of P. napostaense. Early-season post-fire defoliation generally reduced the number of green leaves on tillers… More >

Merchán HD, EE Lutz, AE Morant

Phyton-International Journal of Experimental Botany, Vol.76, pp. 133-142, 2007, DOI:10.32604/phyton.2007.76.133

Abstract In mixed systems (beef and grain), double purpose wheat is an alternative to reduce competition between the winter cereals for grazing and wheat for harvesting. In order to optimize grass production and avoid grain yield decreases, it is necessary to use varieties with long vegetative periods and the last defoliation should be made before the apex changes to the reproductive developmental stage. A study was conducted in the experimental field of the Asociación de Cooperativas Argentinas in Cabildo (38º 36' S, 61º 58' W) to evaluate grass and grain production of the facultative wheat variety (Triticum… More >

Carolina Saint Pierre, Carlos Alberto Busso

Phyton-International Journal of Experimental Botany, Vol.75, pp. 21-30, 2006, DOI:10.32604/phyton.2006.75.021

Abstract This article has no abstract. More >