Morphogenesis on age categories of tillers in marandu palisadegrass

Scientia Agricola

Adenilson José Paiva²  Sila Carneiro Da Silva¹  Lilian Elgalise Techio Pereira²  Fábio Olegário Caminha²  Priscila De Mesquita Pereira²  Vitor Del'Álamo Guarda¹ 

[1] ,USP ESALQ Programa de Pós-Graduação em Ciência Animal e Pastagens

关键词: Brachiaria brizantha;    tiller age;    nitrogen;    morphogenetic characteristics;   

DOI  :  10.1590/S0103-90162011000600003

来源: SciELO

【 摘 要 】

Knowledge regarding morphogenetic characteristics has contributed to the understanding of plant responses to variations in climatic conditions and management practices. However, the original framework has been developed for temperate grass species, and indicates no ontogenetic effect on the expression of morphogenetic traits. Similar information for tropical grass species is scarce, but not less important. This experiment aimed at evaluating the influence of tiller age on the morphogenetic characteristics of continuously stocked marandu palisadegrass swards maintained at 30 cm and fertilized with nitrogen (N). Treatments corresponded to three nitrogen application rates (150, 300 and 450 kg ha-¹ of N) plus the control (no fertilization) and were assigned to experimental units (1,200 m² paddocks) according to a complete randomized block design, with four replications. The following response variables were measured during autumn/winter (Jun. to Jul. 2007) and summer (Feb. to Mar. 2008): leaf appearance rate (LAR), leaf elongation rate (LER) and the age profile of the tiller population. In general, LAR and LER were higher on young (< 2 months old) relative to mature (2 to 4 months old) and old (> 4 months old) tillers during both autumn/winter and summer. During autumn/winter swards were mainly comprised of old tillers (> 4 months old), the opposite happening during summer, when they were mainly comprised of young tillers. Overall, there was no N effect within tiller age categories. Tiller age was an important factor interfering with the morphogenetic responses of marandu palisadegrass, indicating that there is an ontogenetic effect on plant morphogenesis that should be considered further in future studies of this nature

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License