Erreur requête php mysql

Bonjour,
j'ai conçu une requête et j'ai vérifié les noms des attributs dans ma base de donnée sql tout est en norme voici ci joint le texte de ma requête
avec le message d'erreur
<?php
$nb_pla_art=$_POST["nb_pla_art"];
$n_art=$_POST["n_art"];
$mod_art=$_POST["mod_art"];
$mois=$_POST["mois"];
$an_art=$_POST["an_art"];
$mod_art=$_POST["mod_art"];
$dd_trav=$_POST["dd_trav"];
$df_trav=$_POST["df_trav"];
$desc_typ_trav=$_POST["desc_typ_trav"];
$desc_nat_trav=$_POST["desc_nat_trav"];
$haut_carc=$_POST["haut_carc"];
$larg_carc=$_POST["larg_carc"];
$long_carc=$_POST["long_carc"];
$code_mat_pre=$_POST["code_mat_pre"];
$qte_mat_pre=$_POST["qte_mat_pre"];
$typ_mat_pre=$_POST["typ_mat_pre"];
$couleur=$_POST["couleur"];
$hostname = "localhost";
$database ="art-mania";
$username = "root";
$passwords ="";
$connect = mysql_connect($hostname, $username, $passwords) or trigger_error(mysql_error(),E_USER_ERROR);
mysql_select_db($database, $connect);
$requete= "INSERT INTO article (n_art,mois,an_art,nb_pla_art,mod_art) VALUES ('".$_POST['n_art']."','".$_POST['mois']."','".$_POST['an_art']."','".$_POST['nb_pla_art']."','".$_POST['mod_art']."')";
$result = mysql_query($requete, $connect) or die(mysql_error());
$requete= "INSERT INTO dimensions_carcasses (long_carc,larg_carc,haut_carc) VALUES ('".$_POST['long_carc']."','".$_POST['larg_carc']."','".$_POST['haut_carc']."')";
$result = mysql_query($requete, $connect) or die(mysql_error());
$requete= "INSERT INTO nature_travaux (desc_nat_trav,dd_trav,df_trav,desc_typ_trav) VALUES ('".$_POST['desc_nat_trav']."','".$_POST['dd_trav']."','".$_POST['df_trav']."','".$_POST['desc_typ_trav']."')";
$result = mysql_query($requete, $connect) or die(mysql_error());
$requete="INSERT INTO type_matiere_premiere (couleur) VALUES ('".$_POST['couleur']."')";
$result = mysql_query($requete, $connect) or die(mysql_error());
$requete="INSERT INTO matiere_premiere (typ_mat_pre,code_mat_pre) VALUES ('".$_POST['typ_mat_pre']."','".$_POST['code_mat_pre']."')";
$result = mysql_query($requete, $connect) or die(mysql_error());
$requete= "INSERT INTO consommer (qte_mat_pre) VALUES ('".$_POST['qte_mat_pre']."')";
$result = mysql_query($requete, $connect) or die(mysql_error());

if(!$result){
echo("erreur");
}
mysql_close();
et voici le code d'erreur qui se génère

Notice: Undefined index: desc_nat_trav in c:\formulaire_action.php on line 41

Notice: Undefined index: couleur in c:\formulaire_action.php on line 43
merci à vous