Evaluation of the Use of Carbon Isotope Discrimination as a Selection Tool of Perennial Fodder Species for Temporary Pastures

Nicusor Flavius Sima,Valentin Mihai,Stela Cuna,Rodica Maria Sima,Gabriela Cristea

doi:10.15835/nbha3926379

Abstract

Estimation of the relationship between carbon isotope discrimination (Î”13C) in perennial fodder plants and various factors such as climate, fertilization and soil could contribute to a better selection and/or improvement of genotype of fodder species. Theoretical models of carbon isotope discrimination in plants indicate a linear relationship between Î”13C and CO2 partial pressures ratio (pi/pa) from the intercellular spaces (pi) of CO2 in leaves and from the atmosphere (pa). It is also known that between pi parameter and water-use efficiency (WUE) there is a negative correlation. Eight perennial fodder legume and grass mixtures were cultivated on three levels of fertilization in order to assess mixtures for pastures that can provide sustainable quantitative and qualitative yields. The species, which composed the mixtures, were also cultivated as pure crops on the same fertilization conditions. The results of this study indicated that in five of the six species, which composed the mixture with the highest yield, pi/pa values decreased while fertilization doses increased, most likely as a result of variation in water-use efficiency.

Highlights

European Commission working documents, with respect to the impact of agriculture on climate change (Commission of the EC, 2009), revealed that the net CO2 emissions reached 57 million tons in 2007 for EU agricultural lands
This study presents the results of research on the selection of complex mixtures of perennial fodder plants for temporary pastures in the Transylvanian Plain
The influence of the mixture factor in the fodder harvest was analyzed relying on the dry matter yields obtained for each variant and each of the three cuttings

Summary

Introduction

European Commission working documents, with respect to the impact of agriculture on climate change (Commission of the EC, 2009), revealed that the net CO2 emissions reached 57 million tons in 2007 for EU agricultural lands. It is depicted that the increase of the CO2 concentration in the atmosphere will lead to a series of climate changes, including the shift in the annual and seasonal rainfalls and temperature regime, as well as the change in the frequency of extreme conditions, such as drought and floods These extreme conditions would exert their influence on the quality, quantity and stability of agricultural production. For Romania, climate scenarios within the National strategy on the reduction of drought effect have indicated a decrease in summer rainfall levels (MARD, 2008) This deficit will affect the most vulnerable crop plants, such as cereal grains and extensive crop plants. The aim is to set up temporary pastures with complex perennial grasses and legume mixtures alongside annual fodder crops, as the means to adapt their exploitation to present-day and future climate conditions

Methods

Results

Conclusion