Chlorophyll fluorescence estimation of fodder galega (Galega orientalis Lam.) in situ and dependence on different leaf rank and cultivars
Lithuanian University of Agriculture, Studentų 11, Akademija LT–53361, Kauno r., Lithuania;e–mail:email@example.com
The fluorescence measurement in situ of various developmental levels of leaves and various cultivars of fodder galega (Galega orientalis Lam.) was carried out at the Research Station of the Lithuanian University of Agriculture. The object of the investigation was to evaluate the differences of fluorescence of galega cultivars Vidmantai, Laukiai, Melsviai and a breeding number L04–4. The estimation of fluorescence efficiency characterizes the intensity of photosynthesis indirectly and is related to biosynthesis. The yield of the synthesized biomass was also determined. The most intensive fluorescence yield value of the 2nd and the 3rd leaf ranks and plants was determined at the flowering stage in situ. The indices of fluorescence (fluorescence in steady–state light Ft and maximal fluorescence Fm, quantum yield of electron transport Y and electron transport rate ETR) were smaller in a lower leaf rank and in more old leaves of the galega cultivars tested. All quantities of the investigated fluorescence indices statistically significant (P = 0.95) decreased and reached the minimal value both of the older leaves (the 4th–the 6th leaf ranks) and of the youngest (the 1st rank) leaves in comparison with the peak values of the 2nd and the 3rd leaf ranks of all investigated cultivars. It was established that a strong and statistically significant parabolic curvature (0.78145 ≤ η ≤ 0.97385) of different leaf ranks depend on fluorescence indices Ft, Fm and Y/ETR with a leaf rank predomination by 60.3–86.0, 67.2–84.9 and 62.8–94.8% respectively.