|ZOU, GUIHUA - Zhejiang Academy Of Agricultural Sciences|
|ZHOU, LENGBO - Guizhou Academy Of Agricultural Sciences|
|ZHAI, GUOWEI - Zhejiang Academy Of Agricultural Sciences|
|DING, YANQING - Zhejiang Academy Of Agricultural Sciences|
|LU, PING - Chinese Academy Of Agricultural Sciences|
|LIU, HEQIN - Zhejiang Academy Of Agricultural Sciences|
|ZHEN, XUEQIANG - Zhejiang Academy Of Agricultural Sciences|
|LIU, XIUHUI - Zhejiang Academy Of Agricultural Sciences|
|ZHANG, LIYI - Guizhou Academy Of Agricultural Sciences|
|CHEN, HEYUN - Zhejiang Academy Of Agricultural Sciences|
Submitted to: Seed Science Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/13/2019
Publication Date: 9/10/2019
Citation: Zou, G., Zhou, L., Zhai, G., Ding, Y., Lu, P., Liu, H., Zhen, X., Liu, X., Zhang, L., Xin, Z., Chen, H. 2019. A high throughput method for screening deep-seeding tolerance in sorghum. Seed Science Research. https://doi.org/10.1007/s10722-019-00835-0.
Interpretive Summary: Uniform germination and stand are critical for crop success in arid and semi-arid areas. Deep-seeding is a technique used in these regions to allow seeds take up the deep soil moisture. However, the ability of the elongation tissue of seeds to push the seedlings out of soil surface limits the application of deep-seeding technique. Due to small seed size, sorghum is commonly planted <5 cm deep. Scientist from ARS in Lubbock, TX, in collaboration with scientists in Zhejiang Academy of Agriculture Sciences in Hongzhou, China developed a hydroponic method and identified five accessions that have potential mesocotyl (the main elongation tissue in sorghum) length over 20 cm from 105 sorghum accessions. These lines can germinate at planting depth of 20 cm, where other lines fail to germinate. This discovery provides new ways to improve drought tolerance in sorghum.
Technical Abstract: Background: Low soil moisture is a major abiotic stress widespread in arid and semi-arid regions, limiting both seed germination and seedling establishment. Deep-seeding technique allows seeds to use the moisture in deep soil, however, most sorghum seeds cannot penetrate soil layer of 10 cm or deeper. To develop sorghum varieties tolerant to deep-seeding, it is necessary to identify promising lines with good agronomic traits and tolerance to deep-seeding. The common methods, including laboratory test and soil culture, are tedious and time-consuming, and can only screen limited number of accessories in a single study. The aim of this research was to develop a low-cost and high-throughput phenotyping method to facilitate selection for desirable deep-seeding tolerant sorghum lines. Result: A high through hydroponic method was developed to screen sorghum accessions with long mesocotyl under dark conditions. This method revealed large genetic variations for mesocotyl length in a panel of 105 sorghum accessions, which were validated by soil culture and germination in deep-seeding experiments. The lines with long mesocotyl under hydroponic culture had good seedling establishments at planting depth of 20 cm in soil, while the lines with short mesocotyl length could not emerge. Compared to conventional sand or soil cultural methods, the hydroponic culture method was highly efficient in that it requires less time, space, and labor.