Selecting and understanding the mechanisms of drought tolerance in potato cultivars of China
Junhong Qin (360981744@qq.com) Institute of Vegetables of Flowers, Chinese Academy of Agricultural Sciences, Beijing China.
Background: China produces about 25% of the total global potato production area and tonnage of which 60% are cultivated in arid and semi-arid areas in the northwestern parts of China. The potato plant is considered sensitive to drought stress due to its short growing season and its shallow root system, that restricts key physiological and biochemical processes. Focus has been on selecting drought-tolerant potato cultivars. With tetraploid potatoes, both traditional and modern breeding technologies are costly due to the time, and labor requirements to do the research. Our institute has focused on developing fast, simple and efficient methods to accelerate potato drought tolerance evaluations and determine drought tolerant biochemicals that help alleviate the adverse effects soil moisture deficits on potato production.
Partners: We evaluated drought tolerance of more than 300 advanced clones (from International Potato Center) together with Inner Mongolia Agricultural University and Yunnan Academy of Agricultural Sciences for two years. Several selected clones with high drought tolerance were used for the study on physiological and microecological mechanism of potato drought tolerance. Institute of Vegetables of Flowers, Chinese Academy of Agricultural Sciences, Guyuan branch of Ningxia Academy of Agriculture and Forestry Sciences, Ningxia Hui Autonomous Region and Hebei Academy of Agricultural Sciences were involved in these studies.
Evaluation of clones for drought tolerance in field experiments in Inner Mongolia
Results: Ten advanced clones with high drought tolerance were identified. Specific leaf area was determined as a simple, fast and low-cost method for potato drought tolerance evaluation. Doing an in-depth analysis of the soil in the root zone, it was determined that Phenyllactic acid was enriched 11-fold in the rhizosphere soil of the clone CIP 397100.9, with the strongest drought tolerance under deficit irrigation compared to full irrigation. We also confirmed that spraying or irrigating this acid at 225 mg/L concentration can increase potato yield by 24-61% under deficit irrigation and from 12-21% for different cultivars in pot trials. Thus Phenyllactic acid could be applied as a foliar spray to ensure potato production under drought condition.
Spraying phenyllactic acid on drought stressed plants in Ningxia
Lessons learned: After participating in the WPC Adelaide and observing the drought conditions in South Australia and the beautiful appearance of their marketed potatoes my partners and I all agreed to the following steps in our work in northern China:
- Continue with our work on drought tolerance but also enlarge our breeding goals and select drought tolerant cultivars with shining and smooth skin, shallow eyes and early maturity.
- Although there is limited rainfall in South Australia, the percentage of the total field level yield that is marketed is very high. This leads us to address the timing and accuracy of supplementary irrigation technology with limited available water.
- Discussions with both scientists and farmers in South Australia encouraged us in moving ahead with our research and adoption of new drought tolerant cultivars and modern technologies by farmers in China.
The yield of CIP 397100.9 showing good drought tolerance under deficit soil moisture with the rain fed treatment compared to optimal water application with irrigation in Inner Mongolia
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https://www.youtube.com/watch?v=ewmih1i1hgE