Dynamics of stem elongation during the ontogeny of Napier elephant grass

• Grant number: 15/26318-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2016
• End date: February 28, 2017
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Pastures and Forage Crops
• Principal Investigator: Sila Carneiro da Silva
• Grantee: Marcela Bruscagin
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

The morphological development of forage grass plants comprises a sequence of interactive events within and between interconnected phytomers. As a result, the stem elongation process is likely integrated to other aspects related to plant growth and development, being modulated by light competition relations in plant communities, but also defined by ontogenetic programming of individual plants. Aiming at identifying morphological descriptors associated with the beginning of the stem elongation process as, for example, the number of phytomers produced (Lk), a study will be carried out using a isolated plant experimental protocol specially developed for that purpose. The model plant to be used is Pennisetum purpureum Schym. cv. Napier (napier elephant grass). The objective of the study is to characterise how the stem elongation process is regulated in relation to plant ontogenesis using basal tillers and how it would vary throughout the year: spring (October to December, 2015), summer (January to March, 2016) and autumn (April to June, 2016). From the results it is expected to generate a sound basis for understanding what are the determining characteristics of the stem elongation process, if there is a functional ontogenetic programme related to the process and, if so, identify the beginning of the process using a morphological marker, the number of phytomers produced per tiller (Lk). This information is important for definition and planning of grazing management practices and use of forage grasses in pastures in a sustainable manner.