Reivindicación 1: Una composición herbicida que comprende una cantidad sinérgicamente eficaz como herbicida de (a) (±)-2-exo-(2-metilbenciloxi)-1-metil-4-isopropil-7-oxabiciclo[2.2.1]heptano, cualquiera de sus enantiómeros individuales o cualquier mezcla no racémica de estos (herbicida A) y (b) al menos un inhibidor de protoporfirinógeno oxidasa (inhibidor de PPO) seleccionado de flumioxazin (B.1) y sulfentrazone (B.2) (herbicida B). Reivindicación 5: La composición de acuerdo con cualquiera de las reivindicaciones 1 a 4, que también comprende al menos un herbicida C seleccionado del grupo que consiste en acetochlor (C.1), aclonifen (C.2), amicarbazone (C.3), amidosulfuron (C.4), aminopyralid (C.5), amitrole (C.6), asulam (C.7), atrazine (C.8), azimsulfuron (C.9), beflubutamid (C.10), benfluralin (C.11), bensulfuron (C.12), bensulide (C.13), bentazone (C.14), bicyclopyrone (C.15), bifenox (C.16), bispyribac (C.17), bromoxynil (C.18), carbetamide (C.19), carfentrazone (C.20), chloridazon (C.21), chlorpropham (C.22), chlorsulfuron (C.23), chlorthal (C.24), chlortoluron (C.25), clethodim (C.26), clodinafop (C.27), clomazone (C.28), clopyralid (C.29), cycloxydim (C.30), cyclopyrimorate (C.31), cyhalofop (C.32), 2,4-D (C.33), dazomet (C.34), 2,4-DB (C.35), desmedipham (C.36), dicamba (C.37), dichlorprop (C.38), dichlorprop-P (C.39), diclofop (C.40), diflufenican (C.41), -diflufenzopyr (C.42), dimethachlor (C.43), dimethenamid (C.44), dimethenamid-P (C.45), diquat (C.46), dithiopyr (C.47), diuron (C.48), ethametsulfuron (C.49), ethofumesate (C.50), fenoxaprop (C.51), fenoxaprop-P (C.52), fenquinotrione (C.53), flazasulfuron (C.54), florasulam (C.55), fluazifop (C.56), fluazifop-P (C.57), flucarbazone (C.58), flufenacet (C.59), fluometuron (C.60), flupyrsulfuron (C.61), flurochloridone (C.62), fluroxypyr (C.63), flurtamone (C.64), foramsulfuron. (C.65), glufosinato (C.66), glufosinato-P (C.67), glifosato (C.68), halauxifen (C.69), halosulfuron (C.70), haloxyfop-P (C.71), indaziflam (C.72), imazamox (C.73), imazaquin (C.74), imazethapyr (C.75), imazosulfuron (C.76), iodosulfuron (C.77), iofensulfuron (C.78), ioxynil (C.79), isoproturon (C.80), isoxaben (C.81), isoxaflutole (C.82), lenacil (C.83), linuron (C.84), MCPA (C.85), MCPB (C.86), mecoprop (C.87), mecoprop-P (C.88), mesosulfuron (C.89), mesotrione (C.90), metam (C.91), metamitron (C.92), metazachlor (C.93), methiozoline (C.94), metobromuron (C.95), metolachlor (C.96), S-metolachlor (C.97), metosulam (C.98), metribuzin (C.99), metsulfuron (C.100), molinate (C.101), metil arseniato monosódico) (MSMA) (C.102), napropamide (C.103), napropamide-M (C.104), nicosulfuron (C.105), orthosulfamuron (C.106), oryzalin (C.107), oxadiargyl (C.108), oxadiazon (C.109), oxasulfuron (C.110), oxyfluorfen (C.111), pendimethalin (C.112), penoxsulam (C.113), pethoxamid (C.114), phenmedipham (C.115), picloram (C.116), picolinafen (C.117), pinoxaden (C.118), pretilachlor (C.119), prodiamine (C.120), profoxydim (C.121), prometryne (C.122), propaquizafop (C.123), propoxycarbazone (C.124), propyzamide (C.125), prosulfocarb (C.126), prosulfuron (C.127), pyraflufen (C.128), pyridate (C.129), pyroxasulfone (C.130), pyroxsulam (C.131), quinclorac (C.132), quinmerac (C.133), quinoclamine (C.134), quizalofop (C.135), quizalofop-P (C.136), rimsulfuron (C.137), saflufenacil (C.138), sethoxydim (C.139), siduron (C.140), simazine (C.141), sulcotrione (C.142), sulfosulfuron (C.143), tembotrione (C.144), tepraloxydim (C.145), terbuthylazine (C.146), thiencarbazone (C.147), thifensulfuron (C.148), tolpyralate (C.149), topramezone (C.150), tralkoxydim (C.151), tri-allate (C.152), triasulfuron (C.153), tribenuron (C.154), triclopyr (C.155), trifloxysulfuron (C.156), trifludimoxazin (C.157), trifluralin (C.158), triflusulfuron (C.159), tritosulfuron (C.160), ácido 4-amino-3-cloro-6-(4-cloro-2-fluoro-3-metoxifenil)-5-fluoropiridin-2-carboxílico (C.161), bencil 4-amino-3-cloro-6-(4-cloro-2-fluoro-3-metoxifenil)-5-fluoropiridin-2-carboxilato (CAS 1390661-72-9, C.162), imazapyr (C.163), y sus sales, ésteres o amidas aceptables en la agricultura. Reivindicación 6: La composición de acuerdo con cualquiera de las reivindicaciones 1 a 5, que también comprende al menos un protector D seleccionado del grupo que consiste en benoxacor (D.1), cloquintocet (D.2), cyometrinil (D.3), cyprosulfamide (D.4), dichlormid (D.5), dicyclonon (D.6), dietholate (D.7), fenchlorazole (D.8), fenclorim (D.9), flurazole (D.10), fluxofenim (D.11), furilazole (D.12), isoxadifen (D.13), mefenpyr (D.14), mephenate (D.15), ácido naftalenacético (D.16), anhídrido naftálico (D.17), oxabetrinil (D.18), 4-(dicloroacetil)-1-oxa-4-azaspiro[4.5]decano (MON4660, CAS 71526-07-3) (D.19), 2,2,5-trimetil-3-(dicloroacetil)-1,3-oxazolidina (R-29148, CAS 52836-31-4) (D.20), N-(2-metoxibenzoil)-4-[(metilaminocarbonil)amino]bencensulfonamida (CAS 129531-12-0) (D.21) y sus sales, ésteres o amidas aceptables en la agricultura. Reivindicación 7: La composición de acuerdo con cualquiera de las reivindicaciones 1 a 6, que también comprende uno o más auxiliares habituales en la protección de cultivos. Reivindicación 8: El uso de la composición de acuerdo con cualquiera de las reivindicaciones 1 a 7 para controlar la vegetación no deseada. Reivindicación 9: Un método para controlar vegetación no deseada que comprende aplicar a la vegetación o a su locus o aplicar al suelo o al agua, para prevenir el surgimiento o crecimiento de la vegetación no deseada, la composición de acuerdo con cualquiera de las reivindicaciones 1 a 7.Claim 1: A herbicidal composition comprising a synergistically effective amount as a herbicide of (a) (±) -2-exo- (2-methylbenzyloxy) -1-methyl-4-isopropyl-7-oxabicyclo [2.2.1] heptane, any of its individual enantiomers or any non-racemic mixture thereof (herbicide A) and (b) at least one protoporphyrinogen oxidase inhibitor (PPO inhibitor) selected from flumioxazin (B.1) and sulfentrazone (B.2) (herbicide B ). Claim 5: The composition according to any one of claims 1 to 4, which also comprises at least one herbicide C selected from the group consisting of acetochlor (C.1), aclonifen (C.2), amicarbazone (C.3) , amidosulfuron (C.4), aminopyralid (C.5), amitrole (C.6), asulam (C.7), atrazine (C.8), azimsulfuron (C.9), beflubutamid (C.10), benfluralin (C.11), bensulfuron (C.12), bensulide (C.13), bentazone (C.14), bicyclopyrone (C.15), bifenox (C.16), bispyribac (C.17), bromoxynil (C.18), carbetamide (C.19), carfentrazone (C.20), chloridazon (C.21), chlorpropham (C.22), chlorsulfuron (C.23), chlorthal (C.24), chlortoluron ( C.25), clethodim (C.26), clodinafop (C.27), clomazone (C.28), clopyralid (C.29), cycloxydim (C.30), cyclopyrimorate (C.31), cyhalofop (C .32), 2,4-D (C.33), dazomet (C.34), 2,4-DB (C.35), desmedipham (C.36), dicamba (C.37), dichlorprop (C .38), dichlorprop-P (C.39), diclofop (C.40), diflufenican (C.41), -diflufenzopyr (C.42), dimethachlor (C.43), dim ethenamid (C.44), dimethenamid-P (C.45), diquat (C.46), dithiopyr (C.47), diuron (C.48), ethametsulfuron (C.49), ethofumesate (C.50) , phenoxaprop (C.51), phenoxaprop-P (C.52), fenquinotrione (C.53), flazasulfuron (C.54), florasulam (C.55), fluazifop (C.56), fluazifop-P (C .57), flucarbazone (C.58), flufenacet (C.59), fluometuron (C.60), flupyrsulfuron (C.61), flurochloridone (C.62), fluroxypyr (C.63), flurtamone (C. 64), foramsulfuron. (C.65), glufosinate (C.66), glufosinate-P (C.67), glyphosate (C.68), halauxifen (C.69), halosulfuron (C.70), haloxyfop-P (C.71 ), indaziflam (C.72), imazamox (C.73), imazaquin (C.74), imazethapyr (C.75), imazosulfuron (C.76), iodosulfuron (C.77), iofensulfuron (C.78) , ioxynil (C.79), isoproturon (C.80), isoxaben (C.81), isoxaflutole (C.82), lenacil (C.83), linuron (C.84), MCPA (C.85), MCPB (C.86), mecoprop (C.87), mecoprop-P (C.88), mesosulfuron (C.89), mesotrione (C.90), metam (C.91), metamitron (C.92) , metazachlor (C.93), methiozoline (C.94), metobromuron (C.95), metolachlor (C.96), S-metolachlor (C.97), metosulam (C.98), metribuzin (C.99 ), metsulfuron (C.100), molinate (C.101), monosodium methyl arsenate) (MSMA) (C.102), napropamide (C.103), napropamide-M (C.104), nicosulfuron (C.105 ), orthosulfamuron (C.106), oryzalin (C.107), oxadiargyl (C.108), oxadiazon (C.109), oxasulfuron (C.110), oxyfluorfen (C.111), pendimethalin (C.112) , penoxsulam (C.113), pethoxamid (C.114), phenmedipham ( C.115), picloram (C.116), picolinafen (C.117), pinoxaden (C.118), pretilachlor (C.119), prodiamine (C.120), profoxydim (C.121), prometryne (C .122), propaquizafop (C.123), propoxycarbazone (C.124), propyzamide (C.125), prosulfocarb (C.126), prosulfuron (C.127), pyraflufen (C.128), pyridate (C. 129), pyroxasulfone (C.130), pyroxsulam (C.131), quinclorac (C.132), quinmerac (C.133), quinoclamine (C.134), quizalofop (C.135), quizalofop-P (C .136), rimsulfuron (C.137), saflufenacil (C.138), sethoxydim (C.139), siduron (C.140), simazine (C.141), sulcotrione (C.142), sulfosulfuron (C. 143), tembotrione (C.144), tepraloxydim (C.145), terbuthylazine (C.146), thiencarbazone (C.147), thifensulfuron (C.148), tolpyralate (C.149), topramezone (C.150 ), tralkoxydim (C.151), tri-allate (C.152), triasulfuron (C.153), tribenuron (C.154), triclopyr (C.155), trifloxysulfuron (C.156), trifludimoxazin (C. 157), trifluralin (C.158), triflusulfuron (C.159), tritosulfuron (C.160), 4-amino-3-chloro-6- (4-chloro-2 -fluoro-3-methoxyphenyl) -5-fluoropyridin-2-carboxylic (C.161), benzyl 4-amino-3-chloro-6- (4-chloro-2-fluoro-3-methoxyphenyl) -5-fluoropyridine- 2-carboxylate (CAS 1390661-72-9, C.162), imazapyr (C.163), and their salts, esters or amides acceptable in agriculture. Claim 6: The composition according to any one of claims 1 to 5, which also comprises at least one protector D selected from the group consisting of benoxacor (D.1), cloquintocet (D.2), cyometrinyl (D.3) , cyprosulfamide (D.4), dichlormid (D.5), dicyclonon (D.6), dietholate (D.7), fenchlorazole (D.8), fenclorim (D.9), flurazole (D.10), fluxofenim (D.11), furilazole (D.12), isoxadifen (D.13), mefenpyr (D.14), mephenate (D.15), naphthaleacetic acid (D.16), naphthalic anhydride (D.17) , oxabetrinyl (D.18), 4- (dichloroacetyl) -1-oxa-4-azaspiro [4.5] decane (MON4660, CAS 71526-07-3) (D.19), 2,2,5-trimethyl-3 - (dichloroacetyl) -1,3-oxazolidine (R-29148, CAS 52836-31-4) (D.20), N- (2-methoxybenzoyl) -4 - [(methylaminocarbonyl) amino] benzenesulfonamide (CAS 129531-12 -0) (D.21) and its salts, esters or amides acceptable in agriculture. Claim 7: The composition according to any one of claims 1 to 6, which also comprises one or more common auxiliaries in crop protection. Claim 8: Use of the composition according to any one of claims 1 to 7 to control unwanted vegetation. Claim 9: A method for controlling unwanted vegetation comprising applying to the vegetation or its locus or applying to the soil or water, to prevent the emergence or growth of unwanted vegetation, the composition according to any one of claims 1 to 7.