Analysis Of Agronomy And Quality Traits Of Diploid Potatoes From Canada

With rapid development of potato production and continuous expansion of industrialization,potato industry develops rapidly in China, and the need for processing varieties and special usedvarieties was more and more urgent, however, at present the genetic basis of our cultivated varietieswas narrow and inbreeding is obvious, which limit the breeding effort for development of newvarieties to large extent. Introducing new germplasm resources is very necessary. Therefore, theparamount work for breeding is to introduce germplasm resources abroad and broaden the geneticbasis of Solanum tuberosum L. The main purposes of this experiment, laid out in a random completeblock design, are to determine whether the diploid crosses introduced from Canada contain richgenetic variation in agronomic traits and processing traits; and whether superior crosses andgenotypes can be identified in these diploids, which may later be integrated into tetraploids in futurebreeding effort, therefore broadening the genetic basis of tetraploid potato and promotingdevelopment of new cultivars. The main results are as follows.1. Highly significant difference existed among crosses for plant vigor, plant height, stemnumber, tuber number per hill, tuber yield per hill, dry matter content, and reducing sugar content,indicating rich genetic variation in these diploid potatoes.2. There are significant or highly significant correlations in all traits, except for dry mattercontent and reducing sugar content, including plant vigor, plant height, main stem number, tubernumber per hill, and tuber yield per hill.3. As shown by path analysis, selecting for the cross with high mean tuber weight and hightuber number per hill could lead to identify the cross with high yield potential.4. Cluster analysis showed that groupâ…¡(LD05-7) was a population which had high yield andlow reducing sugar content; groupâ… was also a population which had rich genetic resource, withLD05-1 and LD05-9 being high in dry matter content and high yield, and LD05-10 and LD05-13high in dry matter and low in reducing content; groupâ…¢(LT05-5 and LT05-26), the tetraploid potatocontrol, had high yield and high dry matter content.5. Some individual genotypes which have different target traits were selected from diploidpotatoes, such as individual genotype with high dry matter and low reducing sugar content,individual genotype with shallow or very shallow eyes, and individual genotype with different skincolor, different flesh color, and different tuber shape. LD05-1-5-5, LD05-1-61, LD05-2-15, LD05-8-37, LD05-8-48, LD05-12-39, LD05-12-51, and LD05-12-71 were clones on the top of the listselected for their superior agronomic traits and processing traits, and LD05-16-6, LD05-16-34,LD05-16-38, LD05-17-1, and LD05-17-38 were clones selected for their colorful flesh. In a word, based on the performance of tuber traits, tuber number per hill, tuber yield per hill,dry matter content, and reducing sugar content (FW), the diploid crosses tested in this research canbe considered to have rich genetic variation, in which crosses and genotypes with superioragronomic traits and processing traits can be identified, and be used in future potato breedingprogram.