Allele mining of wheat ABA receptor at Ta PYL4 suggests neo-functionalization among the wheat homoeologs

ABA receptors(PYR/PYL/RCAR)play a central role in the water loss control of plants.A previous report indicated that TaPYL4 is a critical gene in wheat that improves grain production under drought conditions and increases water use efficiency.In this study,we analyzed the sequence polymorphisms and genetic effects of TaPYL4s.Based on isolated TaPYL4 genes from chromosomes 2A,2B and 2D,three haplotypes were detected in the promoter region of TaPYL4-2A,and two haplotypes were present in TaPYL4-2B and TaPYL4-2D,respectively.Marker/trait association analysis indicated that TaPYL4-2A was significantly associated with plant height in 262 Chinese wheat core collection accessions,as well as the drought tolerance coefficient(DTC)for plant height in 239 wheat varieties from Shanxi Province in multiple environments.However,the frequencies of favored drought-tolerant haplotype TaPYL4-2A-Hap2 were considerably low,accounting for only 10%,and lines with this certain Hap could be reserved in the breeding program.TaPYL4-2B was significantly associated with grain number,and the favored haplotype TaPYL4-2B-Hap1 was the dominant allele of above 90% in the collection.For TaPYL4-2D,there were no significant differences in these traits between the two haplotypes in either of the two panels.These results indicate that variation might lead to functional differentiation among the homoeologs and the haplotypes had undergone artificial selection during breeding.Two molecular markers developed to distinguish these haplotypes could be used for breeding in water-limited regions.

Reflections on New Trends in the Oil Market and China-Saudi Arabia Energy Cooperation

President Xi Jinping defined energy cooperation as the‘core of cooperation’between China and Arab states,as he addressed the opening ceremony of China-Arab States Cooperation Forum(CASCF)Ministerial Meeting in 2014.1 China and Saudi Arabia,respectively the world’s most important oil importer and exporter,recognise the pivotal status of energy cooperation in bilateral ties.In 2018,Saudi Arabia exported 61.2 million ton of oil(crude oil and oil products)to China,representing the second largest source of supply of China and 11.2%of China’s total oil imports,while China represented the largest oil export market,absorbing 14.4%of Saudi oil export of 2018.The bilateral investment has also started.Saudi Arabia has already constructed and is planning to construct five major petrochemical projects while China and Saudi Arabia have jointly constructed a refinery in Saudi Arabia.New trends are occurring in the global oil market.On the one hand,a tendency of long-term over-supply and low prices has emerged;on the other hand,the competition of oil supply is shifting to Asia.However,these market changes would not weaken China-Saudi energy cooperation.On the contrary,they give more reasons for both sides to strengthen cooperation,so as to address common challenges,especially to promote peace and stability of the Middle East,rationalisation of oil prices,diversification of oil trade denominated currencies,mutual investment in energy field and joint development of renewables.These trends have also indicated the direction for bilateral cooperation to address the challenges.It would be advisable for both countries to open up new prospects in energy cooperation based on the new concept of a community of energy security.