Our data from the SSR fingerprints clearly showed abundant genetic diversity in the wild Aegilops tauschii accessions collected from Iran. The weedy type of Aegilops tauschii accessions collected from the Yellow River region (Shaanxi and Henan) also had moderate genetic diversity. The abundant genetic diversity among the Aegilops tauschii samples collected from a wide range of areas served as a solid foundation for the study of genetic relationships among the wild and weedy types of Aegilops tauschii. Our data further demonstrated that wild Aegilops tauschii accessions collected from Xinjiang of China were closely related to those from some areas in Iran, suggesting that Aegilops tauschii occurring in Xinjiang is a portion of the wild Aegilops tauschii gene pool in the world. Aegilops tauschii is an annual plant species, of which the wild type is widely distributed in Mediterranean and Central Asia, and the weedy type appears as a weed in agricultural fields of many wheat cultivation regions. Why is Aegilops tauschii found in the Yellow River region (Shaanxi and Henan) of China only as weedy populations? Why there were no natural populations with the capacity of self-reproduction found there? Considering that the Yellow River region is geographically isolated from the range of natural distribution of Aegilops tauschii, then in which way this species is disseminated to the central part of China?
The plausible explanation for the disjunctive distribution of Aegilops tauschii in the Yellow River region of China is by human’s activity, through which the long-distance dispersion (e.g., moving crops around) becomes possible. There are two types of Aegilops tauschii: the wild and weedy types. The former develops into self-reproducible populations occurring in natural habitats, but the latter can only survive under the human disturbed agro-ecosystems as weedy populations in wheat farmlands. The Aegilops tauschii accessions found in the Yellow River region belong to the typical weedy type. Aegilops tauschii is a strict self-pollinating species, and the dispersion of its seeds relies essentially on shattering of spikes that fall on the grand at seed maturity, therefore, the distance of seed movement is considerably limited. This species is characterized by having fragile rachis, enclosed seeds with hulled glumes, and strong seed dormancy, and these characters promoted the persistence of Aegilops tauschii as an accompanying weed in the fields and the adjacent areas of cultivated wheat farmland. The Yellow River region was the cradle of Chinese civilization and the centers of agriculture, economy, and culture, as well as the focal point for exchange between China and the West, which provided a prerequisite for the introduction (with wheat) and propagation of Aegilops tauschii, as a weed of wheat crop.
The SSR fingerprint analysis indicated that the weedy type of Aegilops tauschii found in the Yellow River region possesses a relatively high genetic affinity with the wild Aegilops tauschii accessions collected from different localities in Iran. To date, many weedy populations of Aegilops tauschii are still found in the Middle East region, including Iran. This indicates that weedy type of Aegilops tauschii found in the Yellow River region is originated from Iran or the neighboring areas. The weedy populations found in the Yellow River region of China are beyond the natural distribution range of wild Aegilops tauschii. It is therefore extremely difficult to explain the presence of weedy Aegilops tauschii in central China through natural seed dispersal. The only way to interpret the presence of the weedy Aegilops tauschii populations in central China is the human activity-mediated long distance dispersal. The existence of the Silk Road as important trade and cultural transmission routes is well known for a long historical time [1] and [2]. Therefore, the West-and-China communication via the Silk Road has played an essential role in the exchange of agriculture and its relevant technologies, through which the weedy type of Aegilops tauschii was introduced to central China together with common wheat. It is well known that the hexaploid common wheat was originated from Central Asia, from where this crop species was disseminated and cultivated over the world [22] and [23]. Therefore, the introduction of common wheat and its accompanying weed Aegilops tauschii to China from the West, as a part of agricultural exchanges, via the Silk Road provides reasonable explanation to the occurrence of this species in wheat cultivation areas in central China. That can also explain the reason why the weedy type found in China still maintained a close relationship with the wild type of Aegilops tauschii from its center of origin. It is deduced that the civilized ancient China and Persia maintained intimate and frequent exchanges for trade, culture, and scientific technology at about 4000 years ago. Agriculture should have played a predominant
ข้อมูลจากลายนิ้วมือยังคงชัดเจนชุกชุมพันธุ accessions tauschii Aegilops ป่าซึ่งรวบรวมจากอิหร่าน ชนิดวัชพืช accessions tauschii Aegilops ที่รวบรวมจากแม่น้ำพื้นที่ (มณฑลส่านซีและมณฑลเหอหนาน) ยังมีความหลากหลายทางพันธุกรรมระดับปานกลาง ความหลากหลายทางพันธุกรรมมากมายจากตัวอย่าง tauschii Aegilops รวบรวมจากความหลากหลายของพื้นที่ที่เป็นรากฐานสำหรับการศึกษาความสัมพันธ์ทางพันธุกรรมในประเภทป่า และวัชพืชของ Aegilops tauschii ข้อมูลเพิ่มเติมแสดงว่า accessions tauschii Aegilops ป่าที่รวบรวมจากซินเจียงของจีนอย่างใกล้ชิดเกี่ยวข้องกับผู้ที่มาจากบางพื้นที่ในอิหร่าน แนะนำที่ tauschii Aegilops ที่เกิดขึ้นในซินเจียงเป็นส่วนของป่า Aegilops tauschii ยีนพูในโลก Aegilops tauschii เป็นพันธุ์พืชเป็นประจำ ซึ่งชนิดป่าเป็นกระจายอย่างกว้างขวางในเมดิเตอร์เรเนียนและเอเชียกลาง และวัชพืชชนิดปรากฏเป็นวัชพืชในเขตเกษตรกรรมของพื้นที่เพาะปลูกข้าวสาลีมาก ทำไม Aegilops tauschii พบในภูมิภาคแม่น้ำเหลือง (มณฑลส่านซีและมณฑลเหอหนาน) ของจีนเท่าประชากรวัชพืชหรือไม่ จึงมีประชากรไม่ธรรมชาติขนาดของภาพที่ตนเองพบ พิจารณาว่า แม่น้ำคือแยกทางภูมิศาสตร์หลากหลายธรรมชาติกระจายของ Aegilops tauschii แล้วในทางสายพันธุ์นี้ถูกเผยแพร่ให้ส่วนกลางของจีนThe plausible explanation for the disjunctive distribution of Aegilops tauschii in the Yellow River region of China is by human’s activity, through which the long-distance dispersion (e.g., moving crops around) becomes possible. There are two types of Aegilops tauschii: the wild and weedy types. The former develops into self-reproducible populations occurring in natural habitats, but the latter can only survive under the human disturbed agro-ecosystems as weedy populations in wheat farmlands. The Aegilops tauschii accessions found in the Yellow River region belong to the typical weedy type. Aegilops tauschii is a strict self-pollinating species, and the dispersion of its seeds relies essentially on shattering of spikes that fall on the grand at seed maturity, therefore, the distance of seed movement is considerably limited. This species is characterized by having fragile rachis, enclosed seeds with hulled glumes, and strong seed dormancy, and these characters promoted the persistence of Aegilops tauschii as an accompanying weed in the fields and the adjacent areas of cultivated wheat farmland. The Yellow River region was the cradle of Chinese civilization and the centers of agriculture, economy, and culture, as well as the focal point for exchange between China and the West, which provided a prerequisite for the introduction (with wheat) and propagation of Aegilops tauschii, as a weed of wheat crop.The SSR fingerprint analysis indicated that the weedy type of Aegilops tauschii found in the Yellow River region possesses a relatively high genetic affinity with the wild Aegilops tauschii accessions collected from different localities in Iran. To date, many weedy populations of Aegilops tauschii are still found in the Middle East region, including Iran. This indicates that weedy type of Aegilops tauschii found in the Yellow River region is originated from Iran or the neighboring areas. The weedy populations found in the Yellow River region of China are beyond the natural distribution range of wild Aegilops tauschii. It is therefore extremely difficult to explain the presence of weedy Aegilops tauschii in central China through natural seed dispersal. The only way to interpret the presence of the weedy Aegilops tauschii populations in central China is the human activity-mediated long distance dispersal. The existence of the Silk Road as important trade and cultural transmission routes is well known for a long historical time [1] and [2]. Therefore, the West-and-China communication via the Silk Road has played an essential role in the exchange of agriculture and its relevant technologies, through which the weedy type of Aegilops tauschii was introduced to central China together with common wheat. It is well known that the hexaploid common wheat was originated from Central Asia, from where this crop species was disseminated and cultivated over the world [22] and [23]. Therefore, the introduction of common wheat and its accompanying weed Aegilops tauschii to China from the West, as a part of agricultural exchanges, via the Silk Road provides reasonable explanation to the occurrence of this species in wheat cultivation areas in central China. That can also explain the reason why the weedy type found in China still maintained a close relationship with the wild type of Aegilops tauschii from its center of origin. It is deduced that the civilized ancient China and Persia maintained intimate and frequent exchanges for trade, culture, and scientific technology at about 4000 years ago. Agriculture should have played a predominant
การแปล กรุณารอสักครู่..
