MAIZE INBRED LINES PHENOTYPIC CHARACTERIZATION FOR YIELD AND PHOTOSYNTHETIC EFFICIENCY

Abstract

The objective of this study was to demonstrate the potential of chlorophyllfluorescence parameters to characterize maize inbreds to photosynthesis efficiency, andto be used as tool for selection of genotypes under water and nitrogen stresses. Therewere measured chlorophyll content, electron transport rate (ETR) and CO2 assimilation(A) averages, at flowering. ETR and A showed strong correlation, and were able todiscriminate significantly two groups of inbred lines: a) inbred line G1; and, b) inbredlines G2 and G3. The higher photosynthetic capacity of inbred line G1 was explained byits greater carboxylation efficiency. Similar response was observed for total aerialphytomass and grain production. The results showed the nitrogen as being an importantfactor to maize yield, which can be monitored by chlorophyll content and photochemistryparameters of photosynthesis. ETR and (A) proved to be useful parameters to evaluatecontrasting genotypes, with or without water stress.

Keywords

• Zea mays L.
• flowering
• photosynthesis
• chlorophyll fluorescence
• environment stress