Progress 12/12/19 to 09/30/20
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?A MS student, Surbhi Gupta, in Biology was trained and conducted research on water use efficiency in alfalfa under drought. Two visiting scientists (Dr. Bo Han and Dr. Xiangli Ma from Yunnan Agricultural University, China) were trained and conducted the resilience under drought experiments. How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?Goal 1: Developing broadly adapted, climate resilient forages for sustainable cropping systems. We will continue the resilience test with additional genotypes from Dr. Valentin Risso from University of Wisconsin as a collaborator. The greenhouse data will be compared with the field data to determine whether the resilience at seedling stages is correlated with the performance in the field. We will transplant several genotypes that had previously been identified in the greenhouse for freezing and salinity tolerance into the field in spring and early summer 2021 for salt tolerance and freezing tolerance testing. Goal 2: Understanding genotype by environment interactions across multiple forage species This is not a goal of the SD work.
Impacts
What was accomplished under these goals?
Goal 1: Developing broadly adapted, climate resilient forages for sustainable cropping systems. 20% Accomplished We tested alfalfa genotypes for resilience under drought stress using an experimental procedure we previously developed. The genotypes included in the test were: DKA40-16, MA1971, MA1961, 620, Ladak, WS1, WS2, and WS3. DKA40-16 and 620 were two genotypes from a local seed company in South Dakota. MA1961 and MA1971 were from the North Dakota alfalfa breeding program. Ladak was from a local seed company and was used as a control in all the experiments conducted in the greenhouse. WS1, WS2, and WS3 were genotypes from a seed company in Wisconsin and were provided by Dr. Valentin Picasso Risso (University of Wisconsin). Dr. Risso is conducting field tests on alfalfa resilience. In our greenhouse test, four-week-old seedlings in cone-tainers were used. For well-watered treatment, plants were irrigated to meet 100% transpiration need. For drought stress treatment, plants were irrigated to meet only 25% of their transpirational water needs. The surface of the cone-tainers was covered with aluminum foil to reduce evaporation. Transpirational water loss was calculated based on the weight of the cone-tainer and plant measured every three days. Drought stress continued for 3 weeks or longer, until all the plants in each genotype were wilted and stayed wilty for three days. Plants were then re-watered fully to observe recovery as resilience after 4 weeks. Each genotype was re-watered on different days due to wilting occurred on different days among the genotypes. At each stage we collected the data for shoot dry weight, shoot height, number of internode, relative water content, and root dry weight. Many genotypes were sensitive to drought treatment and produced little increase in dry weight upon application of the drought treatment. Ladak, MA1971, and WS2, however, showed a significant increase in dry weight, (226%, 110%, and 85% respectively) after 3 weeks of drought compared to their weights at the start of drought stress. However, drought stress did reduce growth compared to the well-watered control. The net dry weight increase per plant during the 3-week well-watered control was 0.23g, 0.16g, and 0.12g for Ladak, MA1971 and WS2, respectively, compared to only 0.17g, 0.09g and 0.05g under drought conditions. MA1971 and WS2 showed little dry mass increase after re-watering, suggesting that a continued production under drought may hurt the resilience. DKA40-16, WS1, Ladak, and WS3 were the only four genotypes that showed a significant increase in dry mass after re-watering, indicating excellent resilience. WS3 showed a low production of dry mass even under well-watered conditions, and the increase of dry mass after re-watering was also very small compared to other three genotypes. WS1, DKA40-16 and Ladak weighed 0.5, 0.42, 0.39 g DW/plant, respectively, after rewatering, which was double or triple amount of dry mass compared to other genotypes. Interestingly these three genotypes were also among the ones producing the most dry weight under well-watered conditions at the end of the experiment. Among the three, WS1 showed the highest dry mass under well-watered conditions (0.93 g DW/plant) and similar dry mass under drought stress to Ladak (0.25 g DW/plant), making WS1 the most promising genotype for high production under intermitting drought stress conditions. Examination of various physiological traits did not reveal any strong correlation with drought resilience. The only exception was that the three genotypes with the greatest resilience are among the four genotypes showing the highest root to shoot ratio. In addition, these three showed the highest root to shoot ratio after re-watering, suggesting a fast growth and development of root either occurs with or may be important for shoot biomass production after re-watering. Goal 2: Understanding genotype by environment interactions across multiple forage species. 0% Accomplished This is not a goal of the SD work.
Publications
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