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A stalagmite with high 238U content from Yangkou Cave, China, revealed the evolution of the Asian summer monsoon (ASM) between 49.1 and 59.5 ka, and the δ18O values recorded Dansgaard/Oeschger (D/O) events 13-17. The Yangkou record shows a relatively gradual transition into the D/O 14 and 16 events. The discrepancy between the abrupt and gradual transitions of D/O 14 in the records from northern and southern China, respectively, suggests different responses of the ASM to climate changes in the high northern latitudes. The higher resolution δ18O record and more precise 230Th dating indicate that the timing of D/O 14 and 17 in the Hulu records at 53 and 58 ka should be shifted to 54.3 and 59 ka, respectively. The gradual strengthening of the ASM at the onsets of D/O 16 and 14 in our record is different from the abrupt temperature rise in the northern high latitudes. Some other factors must contribute to this relatively gradual ASM change in southern China, but the actual reason is still unknown. [ABSTRACT FROM AUTHOR]

Rice bacterial leaf blight (BB) caused by Xanthomonas oryzae pv. oryzae and bacterial leaf streak (BLS) caused by X. oryzae pv. oryzicola ( Xoc) are two important diseases of rice that often outbreak simultaneously and constrain rice production in much of Asia and parts of Africa. Developing resistant cultivars has been the most effective approach to control BB, however, most single resistance genes have limited value in breeding programs because of their narrow-spectrum of resistance to the races of the pathogen. By contrast, there is little progress in breeding varieties resistant to Xoc since BLS resistance in rice was a quantitative trait and so far only a few quantitative resistance loci have been identified. We reported here the development of a high yield elite line, Lu-You-Zhan highly resistant to both BB and BLS by pyramiding Xa23 with a wide-spectrum resistance to BB derived from wild rice and a non-host maize resistance gene, Rxo1, using both marker assisted selection (MAS) and genetic engineering. Our study has provided strong evidence that non-host R genes could be a valuable source of resistance in combating those plant diseases where no single R gene controlling high level of resistance exists and demonstrated that MAS combined with transgenic technologies are an effective strategy to achieve high level of resistance against multiple plant diseases. [ABSTRACT FROM AUTHOR]

Northwest China is closely adjacent to Central Asia, an intermediate region of the Eurasian continent. Moreover, the Silk Road through the northwest of China once had a vital role in the east-west intercommunications. Nevertheless, little has been known about the genetic makeup of populations in this region. We collected 503 male samples from 14 ethnic groups in the northwest of China, and surveyed 29 Y-chromosomal biallelic markers and 8 short tandem repeats (STRs) loci to reconstruct the paternal architecture. Our results illustrated obvious genetic difference among these ethnic groups, and in general their genetic background is more similar with Central Asians than with East Asians. The ancestors of present northwestern populations were the admixture of early East Asians peopling northwestward and later Central Asians immigrating eastward. This population mixture was dated to occur within the past 10 000 years. The J2-M172 lineages likely entered China during the eastward migration of Central Asians. The influence from West Eurasia through gene flows on the extant ethnic groups in Northwest China was relatively weak.