Study On Correlation Between Major Photosynthetic Properties And Characteristics Related To Yield And Quality Of Potato

The potato (Solanum tuberosum L.) is one of important grain crops in the world, and also major source of starch productionand fine feed for domesticated animal and fowl in some parts of world. In the past, clonal selection adopted by potato breeders was mainly relied on performance of extrinsic and the biological development habits, which had certain constrants. As the development of science and technology, clonal selection can be made based on indicators of physiology and the biochemistry, which means that breeding evaluation would be changed from extrinsic performance to physiological properties. In this experiment, 198 clones selected form breeding populations, Dongnong 303, Zaodabai, Favorite, Yan shu No.4 and Atlantic were used as materials, by which the correlations between photosynthetic properties and characteristics related to yield and quality of tubers had been studied. The purpose is trying to find photosynthetic indicators that can be taken to evaluating tuber yield and quality even during the growing season. Meanwhile, some clones corresponding with the target were identified. The field experiments were carried on in the experimental farm of Northeast Agricultural University, Heilongjiang Province, in 2010, The main results were as following:1 A sample consist of 26 clones taken from 198 clones randomaly, plus 4 varieties were used as materials for mensurating photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO₂ concentration and chlorophyll content. The result showed that significant differences existed in the clonal population on those photosynthetic properties tested. In terms of high efficiency of photosynthesis, some clones are better than varieties taken as control. Considering 5 photosynthetic properties comprehensively, clones such as 23503, 23482, 23507, 23478, 23508 and 23499 are identified as higher photosynthetic rate, which could be utilized in future breeding program .2 By correlation analysis among photosynthetic properties and yield components, significant positive correlation was showed between photosynthetic rate and tuber yield per hill; stomatal conductance and tuber yield per hill; transpiration rate and tuber yield per hill; photosynthetic rate and tuber number per hill; transpiration rate and tuber number per hill; stomatal conductance and tuber number per hill. Tuber number per hill, plant height, the main stem number showed significant positive correlation with yield per hill. Tuber number per hill, plant height showed significant positive correlation with the main stem number. Photosynthetic rate, stomatal conductance showed significant positive correlation with dry matter content. Transpiration rate has an extremely significant positive correlation with dry matter content; chlorophyll content has an extremely significant positive correlation with starch content. Both results from partial correlation analysis and simple correlation analysis are consistent basically. The photosynthetic rate can be taken as the indicator for selecting and breeding potato variety with high yields and good quality.3 Som clones had been identified for various purposes, such as clones with high yield and fewer tuber number per hill (23503,23482,23507,23478), clones with higher dry matter content (23517,23571,23500,23511), clone with higher starch content (23566,23495,23431,23517). Some clones of less reducing sugar content, good quality of chips, good tuber shape, yellowish pink flesh, shallow eyes were also identified.On all accounts, significant correlation between photosynthetic properties and characteristics related to yield and quality existed factually, which could be used as measures for evaluating clones in potato breeding.