Arbuscular mycorrhizas increase survival, precocity and flowering of herbaceous and shrubby species of early stages of tropical succession in pot cultivation

• Published in: Journal of tropical ecology 2014-11, Vol.30 (6), p.599-614
• Main Authors: Rondina, Artur Berbel Lirio, Lescano, Luis Eduardo Azevedo Marques, de Almeida Alves, Ricardo, Matsuura, Enio Massao, Nogueira, Marco Antonio, Zangaro, Waldemar
• Format: Article
• Language: English
• Subjects: Agricultural soils; Biological and medical sciences; Biology and morphogenesis of the reproductive apparatus. Photoperiodism, vernalisation; Ecological succession; Flowering; Fundamental and applied biological sciences. Psychology; Fungal infections; Fungi; Leaves; Mycorrhizal fungi; Nutrient concentrations; Plant ecology; Plant growth; Plant physiology and development; Plant roots; Plant species; Plants; Prairie soils; Rainforests; Soil fertility; Soils; Survival; Symbiosis; Tropical soils; Vegetative and sexual reproduction, floral biology, fructification
• ISSN: 0266-4674; 1469-7831
• DOI: 10.1017/S0266467414000509

Arbuscular mycorrhizal fungi (AMF) are an important biotic factor that influences tropical ecological succession and differently affect the woody species belonging to different successional stages. However, little is known about the influence of AMF on growth and reproduction of herbaceous and shrubby species of early phases of tropical succession. Thus, we assessed the effect of AMF on the development of 27 heliophilous herbaceous and shrubby tropical species. Plants were grown in greenhouse, in low- and high-fertility soils, with or without AMF, for 100 d. Most species grown with AMF exhibited high root infection intensity (≈80%), irrespective of soil fertility. In the low-fertility soil, non-mycorrhizal plants exhibited about 88% less shoot dry mass (SDM) than mycorrhizal plants, and AMF were crucial for the survival of most species. Non-mycorrhizal plants also had lower relative growth rate (RGR), total leaf area (TLA), leaf area expansion (LAE) and total root length (TRL). Six species flowered in the low-fertility soil, and flowering increased with AMF in one plant species and four species only flowered when mycorrhizal. In the high-fertility soil, non-mycorrhizal plants exhibited about 13% less SDM than mycorrhizal plants and also exhibited lower TLA, LAE, and nutrient concentrations in shoots. On the other hand, no major changes were observed for RGR, TRL and root dry mass for most of the species. Sixteen plant species flowered in the high-fertility soil, but most had earlier (11) and more abundant (10) flowering when mycorrhizal. Thus, AMF have different influences on the survival, growth and flowering of herbaceous and shrubby tropical species, depending on soil fertility: in low-fertility soil, AMF especially affect the survival, growth and flowering, whereas in high-fertility soil, AMF mainly influence the shoot nutrient concentrations and flowering.