diff --git a/src/openalea/adel/astk_interface.py b/src/openalea/adel/astk_interface.py
index c22e1fcc..5cf99890 100644
--- a/src/openalea/adel/astk_interface.py
+++ b/src/openalea/adel/astk_interface.py
@@ -297,7 +297,7 @@ def grow(self, g, time_control):
         except:
             data = time_control
             tt = self.thermal_time(data.index, data)
-            dday = tt[-1]
+            dday = tt.iloc[-1]
 
         # refg = self.setup_canopy(age = self.canopy_age)
         self.canopy_age += dday
diff --git a/src/openalea/adel/dresser.py b/src/openalea/adel/dresser.py
index fd58ca7a..0ed591b8 100644
--- a/src/openalea/adel/dresser.py
+++ b/src/openalea/adel/dresser.py
@@ -310,7 +310,8 @@ def plant_table(dimT, convert=None):
         inplace=True,
     )
     if convert is not None:
-        df.loc[:, ("Ll", "Lw_shape", "Gl", "Gd", "El", "Ed")] *= convert
+        cols = ["Ll", "Lw_shape", "Gl", "Gd", "El", "Ed"]
+        df[cols] *= convert
     # add mandatory topological info and sort from base to top
     df.loc[:, "axe_id"] = "MS"
     df.loc[:, "ms_insertion"] = 0
diff --git a/src/openalea/adel/postprocessing.py b/src/openalea/adel/postprocessing.py
index cc556d64..dc58eaf2 100644
--- a/src/openalea/adel/postprocessing.py
+++ b/src/openalea/adel/postprocessing.py
@@ -356,12 +356,10 @@ def phenology(adel_output_df):
         if indexes_of_all_non_null_Lsen.size == 0:
             SSI = 0.0
         else:
-            nonzero_Lvsen_indexes = group.index[group.Lvsen.to_numpy().nonzero()]
-            SSI = group["numphy"][nonzero_Lvsen_indexes[0]] - 1
-            if len(nonzero_Lvsen_indexes) > 0:
-                Lvsen_values = group["Lvsen"].loc[nonzero_Lvsen_indexes]
-                L_shape_values = group["L_shape"].loc[nonzero_Lvsen_indexes]
-                SSI += (Lvsen_values / L_shape_values).sum()
+            nz = group.loc[group["Lvsen"] != 0]
+            if not nz.empty:
+                SSI = nz["numphy"].iloc[0] - 1
+                SSI += (nz["Lvsen"] / nz["L_shape"]).sum()
 
         # indexes_of_all_null_Lshape = L_shape[L_shape == 0.0].index
         HS_final = group["HS_final"][group.first_valid_index()]