Studies on improvement of cultural efficiency and practical use in anther culture of wheat triticum aestivum l
Hur, H.S.
Research Reports of the Rural Development Administration 31(4 BIOTECHNOL): 18-42
1989
Accession: 007832215
The present studies were conducted to improve the cultural efficiency currently remaining at low level in anther culture of wheat (Triticum aestivum L.). More emphasis was given to find out a practical indicator for choosing explants on a large scale and clarify whether the plantlets differentiated from the microspores or the somatic cells of anther relatives. Some of major results obtained are summarized as follows: It was possible to presume the stages of pollen development with the apical portion of spike from the 2nd leaf auricle in Korean wheat cultivar Chokwang in vivo. When the apical portion was reached to the range of 0.5-1.5cm, the stages of pollen in the middle part of spike were in the mid or late-uninuclease stage which is considered to be the optimal stage for anther culture in wheat. The most effective pretreatment condition was 3 days of 5.degree. C with the tillers containing spikes inside and the rate of callus induction of the condition was improved up to 2.4 times over non-treatment in Chokwang. The C17 medium gave better results in callus induction than MS and N6 medium for Chokwang and Korean native variety Jaeremil while the rate of plant differentiation was high in N6Yi medium for Chokwang and 1/2MS medium for Jaeremil, respectively. The cultural efficiency differed from the media employed and the differences were higher inter the callus induction media than that of plant differentiation media. At the same time, carry over effect was recognized in C17 medium because the calli induced from the medium provided higher response for all three kinds of plant differentiation media; MS, 1/2 MS and N6Y1 medium. There were great differences in response of callus induction as well as plant differentiation among ten wheat varieties and five F1-hybrids from intervarietal crosses. Mean rate for callus induction and plant differentiation of these materials was 8.9% and 32.0%, respectively, while 20% out of total differentiated plantletes were chlorophyll deficient. Microscopic investigation for the somatic cells of anther-derived plantlets was revealed that there were 77.8% of haploids, 17.8% of diploids, 2.2% of tetraploids and 2.2% of mixoploid plantlets, respectively. The results presented indicated that the rate of haploid plantlets in wheat was much higher than in rice or barley.