|CHOE, EUNSOO - Illinois Crop Improvement Association|
|KO, YOUNHEE - Hankuk University Of Foreign Studies|
Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/31/2021
Publication Date: 6/17/2021
Citation: Choe, E., Ko, Y., Williams II, M.M. 2021. Transcriptional analysis of sweet corn hybrids in response to crowding stress. PLoS ONE. 16(6). Article e0253190. https://doi.org/10.1371/journal.pone.0253190.
Interpretive Summary: Generally as plant density increases, plants experience crowding stress due to resource competition including nutrients, water, and light quantity and quality. Several have proposed that crowding stress tolerance (CST) in crops could be exploited to improve productivity and profitability, since the crops would maximize use of limited resources. The research identified candidate genes associated CST in sweet corn. The impact of the research is that it sheds light on potential mechanisms of CST in sweet corn, which could lead to the future development and use of hybrids with superior tolerance to crowding stress.
Technical Abstract: Crop tolerance to crowding stress, specifically plant population density, is an important target to improve productivity. Due to limited knowledge of biological mechanisms involved in crowding stress in sweet corn, a study was conducted to 1) investigate phenotypic and transcriptional response of sweet corn hybrids under different plant densities, 2) compare the crowding stress response mechanisms between hybrids and 3) identify candidate biological mechanisms involved in crowding stress response. Yield per hectare of a tolerant hybrid (DMC21-84) increased with plant density. Yield per hectare of a sensitive hybrid (GSS2259P) declined with plant density. Transcriptional analysis found 694, 537, 359 and 483 crowding stress differentially expressed genes (DEGs) for GSS2259P at the Fruit Farm and Vegetable Farm and for DMC21-84 at the Fruit Farm and Vegetable Farm, respectively. Strong transcriptional change due to hybrid was observed. Functional analyses of DEGs involved in crowding stress also revealed that protein folding and photosynthetic processes were common response mechanisms for both hybrids. However, DEGs related to starch biosynthetic, carbohydrate metabolism, and ABA related processes were significant only for DMC21-84, suggesting the genes have closer relationship to plant productivity under stress than other processes. These results collectively provide initial insight into potential crowding stress response mechanisms in sweet corn.