ЭлБиб

C E L L CU LTUR E FO R PRODUCING PLANTS R E SISTA N T TO BIOTIC AND ABIOTIC

FACTORS

EXOMETABOLITES OF RICE CALLI OF BLAST-RESISTANTCULTIVARS

ARETOXIC TO THE CAUSALAGENTOF THE DISEASE

L.M.Gaivoronskaya,L.B.E.Magallona, VP.Lapikova,T.D.Pasechnik,

*A.A.Aver’yanov

Russian People s Friendship University (Moscow, Miklukho-Maclay str.),

*Research Institute o fPhytopathology (B. VyazemyMoscow region), E-Mail:

Plant breeding including selection fo r resistance to infective diseases

can be intensified using cell cultivation. The work with intact plants is usually

based on an estimation of visual symptoms which, however, are not expressed

in vitro.

This requires a search for other resistance markers remained in cell

cultures. We found earlier that during both varietal and induced rice resistance

to blast disease, intact leaves liberate into an infective drop some metabolites

suppressing the spore germination of the causal fungus

Маgnароrthe grisea.

The aim of the study was to reveal whether rice callus culture exhibit

the analogous fungitoxic responses, and do they depend on varietal

resistance to the disease. Calli were obtained from rice seeds o f cultivars of

either susceptible or resistant to the fungal strains tested. The cultivars from

the second group represented different types of resistance. Callus fragments

were submerged into a spore suspension. Several hours later the spore

germination was counted. Then the incubation medium (diffusate) was

collected, released from spores, and the germination of new spores in this

diffusate was tested.

It was found that that spores developed freely in the direct contact with

a callus. However, theirgermination was suppressed in diffusates of infected

calli probably due to relatively slow excretion of a toxic matter. The level of

callus diffusate fungitoxicity of all resistant cultivars was significantly higher

than that of the susceptible ones.

Therefore, the ability of rice cells to excrete antifungal exometabolites

in response to blast infection is peculiar not only to intact plants but also to

callus cultures. This ability might be another marker of the varietal disease

resistance

in vitro.

3 6 3

Научная электронная библиотека ЦНСХБ