Chromosomal Location Of Genes Controlling Seven Characters In Dwarfing Polish Wheat By Monosomic Analysis

Dwarfing Polish Wheat (Triticum polonicum L.) , a new dwarfism resource of tetraploid, was collected in Tulufan, Xinjiang, China. It is the only one T. polonicum with dwarfing trait in China. This resource was insensitive to GA₃, and the genes controlling the dwarfing trait are recessive in polish wheat genetic background. In order to utilize successfully the dwarfism resource in breeding, the present study employed a set of Langdon durum wheat monosomic lines to identify the chromosomal location of the genes of plant height, spikes number per plant, spike length, spikelets number per spike, spike internode length, kernels number per spike and thousand kernels weight. These important agricultural characters contribute to the plant yield. T-test and Duncan variance analysis were adopted in F₁ and F₂ monosomic analysis. The main results are as follows:1. Dwarfism. Two master recessive dwarfing genes were located on 3B and 5B chromosomes. Recessive minor genes were also found on chromosomes 1A, 2A, 4A, 5A and 6A. Genes on 3B, 5B, 1 A, 4A, 6A chromosomes are new ones.2. Spikes number/plant. Dominant genes on chromosomes 2A, 1B, 2B, 3B, 4B, 7B influence this character. The genes on chromosomes 1B, 2B, 3B, 4B, 7B increase strongly the spikes number, and 2A chromosome is less effective. Gene on chromosome 3B is a new one.3. Spike length. Dominant genes on 1A, 2A, 2B, 4B and 5B chromosomes increase strongly the spike length. Dominant genes on 7A, 3B, 7B chromosomes are less effectiveto increase the spike length.4. Spikelets number/spike. Dominant genes were found on chromosomes 1A, 2A, IB, 3B, 5B and 6B. They all have strong effect on the character except the gene on IB chromosome. 4B chromosome carries recessive gene that inhibits the spikelet development. The gene on 1A chromosome is a new one.5. Spike internode length. Dominant genes located on 1A, 7A, 2B, 4B chromosomes increase the length with strong effect. Minor dominant genes were also found. They are located on 4A, 6A, 5B, 7B chromosomes. Genes on chromosomes 1 A, 4A, 6A, 7A, 4B, 5B, 7B are new ones.6. Kernels number/spike. The genes on 5A, 4B, 7B chromosomes reduce significantly kernels number per spike, and the gene on chromosome 2B reduce very significantly kernels number per spike.7. Thousand kernels weight. Chromosomes 2A, 3B, 5B and 6B have genes that reduce strongly thousand kernels weight. And the genes on 1A, IB chromosomes reduce this character with little effect. The gene on 4B chromosome increases strongly thousand kernels weight.8. The result of the present experiment suggested that 3B and 5B chromosomes in the Dwarfing Polish Wheat reduce the plant height, while increase spikes number per plant, spike length and spikelets number per spike. And the two chromosomes also reduce thousand kernels weight.