TY  - PRO
AU  - Zedgenidze,I.
AU  - Alpaidez,L.
AU  - Bedoshvili,D.
AU  - Darsavelidze,T.
ED  - Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT)
ED  - 
TI  - Biological tolerance of gerogian wheat
U1  - 633.1147 
PY  - 2004///
CY  - Tbilisi (Georgia)
PB  - CIMMYT
KW  - Disease resistance
KW  - AGROVOC
KW  - Drought resistance
KW  - Experimentation
KW  - Hybridization
KW  - Puccinia glumarum
KW  - Puccinia graminis
KW  - Puccinia recondita
KW  - Rusts
KW  - Stems
KW  - Varieties
KW  - Wheat
KW  - Genotypes
KW  - CIMMYT
N1  - Abstract only
N2  - Late in 19th century an Austrian researcher Kobb, investigating the reaction of wheat varieties to stem rust, noticed that at the identical intensity of inoculation the extent of productivity deterioration differs in different varieties. He called this phenomenon "rust resistance" or "rust tolerance". Breeding of plants on tolerance has become one of the basic objectives of the breeding practice. Tolerance is the ability of a cell, an individual plant or the whole crop to decrease the damage caused by pathogens as well as to restrict the growth, development and propagation of pathogen in a host-plant and consequently in the whole crop. The mechanism of tolerance considerably varies according to the varieties, species and types of diseases. Breeding and adoption of tolerant plants through hybridization and experimental mutagenesis are realized much quicker than breeding of authentically resistant plants. Ecotypes of Georgian cereal wheat Dolis Puri are remarkable for their high natural tolerance. The following varieties of these ecotypes have been studied: Akhaltsikhe Tsiteli Doli, Kakheti Tsiteli Doli, Doli 35-4 and Doli 18-46. Evaluation of their tolerance to wheat rusts (Puccinia glumarum, p recondita, P. graminis) was carried out during the vegetation period. The intensity of disease development was evaluated according to the Strakhov scale. Similar observations were done on check varieties (Bezostaya 1 and the durum wheat Shavpkha). 25 plants of each variety diseased at up to 15% and the same number of plants diseased at over 65% were selected in the stage of complete maturity and analyzed biometrically. Special attention was paid to the productivity characteristics of spikes (length of spike, number of spikelets per spike, grain quantity per spike and weight of 1000 grains) and yield per plant. The research has shown that yield per plant for the variety Doli 35-4 in the plants diseased at 5-15% makes 5.8 g, while for the plants diseased at up to 65% it makes 4.9 g. The difference makes 0.9 g. The same difference for varieties Akhaltsikhe Tsiteli Doli, Kakhuri Tsiteli Doli and Doli l8-46 reached 1.1 g, 1.3 g and 1.5 g, respectively. In case of the check variety Bezostaya 1 yield per the plant in the plants diseased at 15% was 8.4 g and in the plants diseased at 65% it was recorded as 6.5 g, i.e. the loss of grain due to the disease intensity was 1,9g. Another check variety Shavpkha showed 2,5 g grain loss. The above data clearly demonstrates that the varieties of Dolis Puri are characterized by high tolerance towards field diseases. In cases of identical disease intensity their productivity is not deteriorated equivalently as compared to the check varieties Bezostaya 1 and Shavpkha. These varieties have also demonstrated high tolerance at irradiation with gamma rays in critical doses. Decrease of productivity in the survived plants is lower as compared to durum wheat varieties
ER  -