diff --git a/meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py b/meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py
index 6bc78d42..6c6698d6 100644
--- a/meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py
+++ b/meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py
@@ -104,7 +104,7 @@ class BootimgEFIPlugin(SourcePlugin):
                         (get_bitbake_var("KERNEL_IMAGETYPE"), get_bitbake_var("INITRAMFS_LINK_NAME"))

             label = source_params.get('label')
-            label_conf = "root=%s" % creator.rootdev
+            label_conf = f" root={creator.rootdev}" if creator.rootdev else ""
             if label:
                 label_conf = "LABEL=%s" % label

@@ -201,7 +201,8 @@ class BootimgEFIPlugin(SourcePlugin):
             boot_conf += "linux /%s\n" % kernel

             label = source_params.get('label')
-            label_conf = "LABEL=Boot root=%s" % creator.rootdev
+            label_conf = "LABEL=Boot"
+            label_conf += f" root={creator.rootdev}" if creator.rootdev else ""
             if label:
                 label_conf = "LABEL=%s" % label

@@ -366,7 +367,7 @@ class BootimgEFIPlugin(SourcePlugin):

             with tempfile.TemporaryDirectory() as tmp_dir:
                 label = source_params.get('label')
-                label_conf = "root=%s" % creator.rootdev
+                label_conf = f" root={creator.rootdev}" if creator.rootdev else ""
                 if label:
                     label_conf = "LABEL=%s" % label

diff --git a/meta/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py b/meta/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py
index d5040b72..5dd76761 100644
--- a/meta/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py
+++ b/meta/scripts/lib/wic/plugins/source/bootimg-pcbios-isar.py
@@ -140,14 +140,21 @@ class BootimgPcbiosIsarPlugin(SourcePlugin):

             syslinux_conf += "KERNEL " + kernel + "\n"

-            syslinux_conf += "APPEND label=boot root=%s %s\n" % \
-                             (creator.rootdev, bootloader.append)
+            # Check if rootdev exists
+            root_param = f"root={creator.rootdev}" if creator.rootdev else ""
+
+            syslinux_conf += f"APPEND label=boot {root_param} {bootloader.append}\n"

             # if we are using an initrd, smuggle it in
             if initrd:
-                syslinux_conf = syslinux_conf.replace(
-                    " root=%s " % (creator.rootdev),
-                    " root=%s initrd=%s " % (creator.rootdev, initrd))
+                if root_param:
+                    syslinux_conf = syslinux_conf.replace(
+                        root_param,
+                        f" {root_param} initrd={initrd} ")
+                else:
+                    syslinux_conf = syslinux_conf.replace(
+                        " label=boot ",
+                        f" label=boot initrd={initrd} ")

         logger.debug("Writing syslinux config %s/hdd/boot/syslinux.cfg",
                      cr_workdir)