Analysis Of Agronomic And Quality Traits In Advanced Dutch Potato Clones

As the continuous development of the economy, potato processing industry is also rapidly developing and growing in China. But the potato varieties developed in the past are mainly for fresh market. The aim of potato breeding is high yield and high disease resistance. Less attention is paid to the development of processing type of variety and the quality of the variety. Therefore, germplasm abroad should be introduced and used for developing processing type of variety suitable to the geographic and climatic conditions in China .The Netherlands is a leading country in potato breeding and introduction of Dutch germplams and selection in China for the development of processing type of variety has practical value. In this researech, 27 advanced clones of 9 crosses, which were introduced from the Netherlands, were grown in two locations (Nehe and Jiagedaqi) and in two years (2009 and 2010), using the varieties Shepody (French fry) and Kexin 18 (table) as controls, to study their performance of the agronomic traits, yield traits, processing traits and after-cooking darkening in order to understand their adaptation to Heilongjiang environments, hoping that these Dutch germplasm could produce some clones suitable for processing into French fry, and therefore the development of processing type of variety could be accelerated in China. The main results were summarized as follows:(1) Highly positively significant correlation were found between main stem number and total yield, marketable yield and total yield, reducing sugar content and French fry grades, and after- cooking darkening grades (immediately) and after-cooking darkening grades (24 h after cooking). Main stem numbers was positively significantly correlated to marketable yields. Specific gravity was negatively significantly correlated to reducing sugar content, and negatively highly significantly to French fry grade. No correlation was found for yield with specific gravity and reducing sugar content.(2) Main stem numbers had a highly significantly negative partial correlation to marketable yields, and highly significantly positive partial correlation to total yields. Marketable yield had a highly significantly positive partial correlation to total yield. Reducing sugar content had a highly significantly negative partial correlation to French fry grade, and after-cooking darkening grades (immediately) had a highly significantly positive partial correlation to after-cooking darkening grade (24 h aftert cooking).(3) Marketable yield had a large positive direct contribution to total yield (0.9080), followed by main stem numbers (0.3191); total yields had a large positive direct contribution to marketable yield (1.0646) followed by main stem number (-0.1374), based on path analysis after optimizing the eqaiton by stepwise regression.(4) HJ7-16 was a highest yielding clone, particularly suitable for planting in Nehe. Its total yield, marketable yield and specific gravity was higher than both Kexin 18 and Shepody, and French fry grade was better than Shepody. Therefore, HJ7-16 could be evaluated further for its potential as a French fry variety. HJ7-36 and HJ3-18 had high marketable yields and were stable in yield performance, suitable for growing in both Nehe and Jiagedaqi. These two clones were better in marketable yield and after-cooking darkening than both Kexin 18 and Shepody, and therefore could be evaluated further for their potential as table stocks.(5) HJ1-52, HJ1-36, HJ1-6 and HJ2-26 were low in reducing sugar content and high in French fry grade and specific gravity, but their yields was not high. They could be used as parents for breeding French fry variety. HJ3-60 and HJ6-10 were relatively high in yields, and after-cooking darkening grades. Their cooking types were AB. These clones could be used as parents for breeding table stocks.In short, based on the evaluation of 27 advanced clones from nine crosses introduced from the Netherlands for the traits of plant, yield, and quality, it was proved that the Dutch germplasm could be used in the potato breeding programme in China, from which French fry varieties and talbe varieties could be developed.