Tolerantnost domačih kultivarjev koruze na stebelno trohnobo koruze

Ludvik ROZMAN¹, Branko Palaveršić², Lea MilevoJ³, Antun Vragolović⁴, Nevenka VALIČ⁵

^1,3,5 Biotehniška fakulteta, Oddelek za agronomijo, SI-1000 Ljubljana, Slovenija
^2,4 Institut za oplemenjivanje i proizvodnju bilja, d.d., HR-10000 Zagreb, Hrvaška

V skupnih dveletnih proučevanjih so bili preizkušeni domači kultivarji koruze na odpornost proti stebelni trohnobi koruze. V preizkušanje sta bili vključeni 2 slovenski populaciji, 4 slovenski ter 15 hrvaških hibridov koruze. V prvem letu je bil napad bolezni znatno večji na dveh lokacijah na Hrvaškem (Rugvica, Ludbreg) kot v Sloveniji (Jable, Ljubljana). Sorazmerno s tem je bil povečan tudi lom stebla. Statistično značilne razlike so bile v tolerantnosti kultivarjev na stebelno trohnobo v razmerah naravne okužbe. Najodpornejši so bili hibridi H-13/99, H-9/99, H-5/99 in H-7/99, najobčutljivejši pa H-4/99, H-6/99 ter obe populaciji. Leta 1999 je bil prvič v Sloveniji zabeležen tudi napad antraknoze stebla, ki ga povzroča gliva Colletotrichum graminicola (/Ces./ G. W. Wils.). V Jablah je bilo okuženo, odvisno od kultivarja, od 2% do 35% rastlin. V drugem letu preizkušanja je bilo v Jablah prvič izvedeno testiranje na imenovano glivo z umetno infekcijo. Med hibridi so bile ugotovljene nekatere signifikantne razlike samo v razmerah umetne okužbe, ki je bila občutno močnejša kot v razmerah naravne okužbe, kjer med hibridi ni bilo signifikantnih razlik. Med hibridi ni povezave na odpornost glede na lokacijo ali način okužbe, pri umetni okužbi sta najobčutljivejša H-15/00 in H-7/00, najodpornejša pa H-2/00 in H-13/00. Pri naravni okužbi pa so občutljivi H-6/00, H-7/00 (Jable) ter H-13/00 in H-10/00 (Rugvica), odporni pa H-4/00, H-13/00 (Jable) ter H-12/00 in H-15/00 (Rugvica).

ABSTRACT

The tolerance of local maize cultivars to stalk rot

The resistance against stalk rot of two slovenian populations, and four slovenian and 15 croatian maize hybrids, was investigated during two years. In the first year, the attack was stronger on two locations in Croatia (Rugvica, Ludbreg), when compared with  the slovenian locations (Jable, Ljubljana). The incidence of broken stalks was higher in locations where the disease was more severe. There were significant differences for stalk rot (in field conditions). The most tolerant hybrids were H-13/99, H-9/99, H-5/99 and H-7/99, but H-4/99, H-6/99, and both populations were found to be the most susceptible. In 1999, the stalk anthracnose, caused by the fungus Colletotrichum graminicola (/Ces./ G. W. Wils.) was detected in Slovenia for the first time. In the experimental station at Jable, 2-35 % of the plants of various hybrids were affected by this fungus. The first artificial inoculation with this fungus took place in 2000. The significant differences among the studied cultivars were found only when the plants had been  artificially inoculated. The most susceptible cultivars were H-15/00 and H-7/00, and the most tolerant were H-2/00 and H-13/00. However, in natural conditions the most susceptible were H-6/00 and H-7/00 at Jable, and H-13/00 and H-10/00 at Rugvica, but H-4/00 and H-13/00 (Jable), and H-12/00 and H-15/00 (Rugvica) appeared to be tolerant.