Search Results

You are looking at 1 - 10 of 198 items for :

  • "real-time PCR" x
  • All content x
Clear All
Free access

Timothy Coolong, William Randle, and Ronald Walcott

Onion (Allium cepa L.) is an economically important vegetable in the United States. Though considered a minor crop in terms of total acreage, onions have high value when compared to other crops and, nationally, their value approaches $800 million. Because harvested onions are routinely stored for long periods, disease can be a major obstacle to the industry. The primary disease reported in stored onions is botrytis neck rot caused by the fungus Botrytis allii (syn. B. aclada). Losses from neck rot can approach 35% of the stored crop. In order to accurately quantify the level of B. allii inoculum in bulbs at harvest to be able to predict potential botrytis neck rot in storage, a quantitative real-time PCR test to quantify levels of B. allii DNA present in onion bulb tissue has been developed. We have employed the TaqMan real time PCR assay and report log-linear (R 2= 0.9915) relationship between B. allii DNA concentration and cycle threshold (Ct) value with a detection limit of 5 pico gram/microliter DNA. In addition, a log-linear standard curve plotting mycelial dry weight against Ct value has been developed to allow prediction of mycelial weight in onion tissue at harvest. Currently, the ability of this test to predict botrytis neck rot during storage is being tested.

Free access

Takashi Akagi, Yumi Takeda, Keizo Yonemori, Ayako Ikegami, Atsushi Kono, Masahiko Yamada, and Shinya Kanzaki

(arrows indicate the primers). Primers with an asterisk were used in quantitative real-time PCR analysis for M ast ( Table 3 ). Materials and Methods Identification of an ast-linked marker allele conserved among cultivars. To confirm

Free access

K.S. Ling, C.A. Clark, C. Kokkinos, J. R. Bohac, S.S. Hurtt, R. L. Jarret, and A. G. Gillaspie

Sweet potato virus disease (SPVD) is the most devastating virus disease on sweetpotato [Ipomoea batatas (L.) Lam] world wide, especially in East Africa. However, weather it is present in the U.S. is unknown. SPVD is caused by co-infection of sweetpotato feathery mottle virus (SPFMV) and sweetpotato chlorotic stunt virus (SPCSV). Presence of two other potyviruses, sweetpotato virus G (SPVG) and Ipomoea vein mosaic virus (IVMV) has also been confirmed in the U.S. Sweet potato leaf curl virus (SPLCV), a whitefly (Bemisia tabaci) transmitted Begomovirus, also has the potential to spread to commercial sweetpotato fields and poses a great threat to the sweetpotato industry. The U.S. collection of sweetpotato germplasm contains about 700 genotypes or breeding lines introduced from over 20 different countries. Newly introduced sweetpotato germplasm from foreign sources are routinely screened for major viruses with serology and graft-transmission onto indicator plants (Ipomoea setosa). However, a large portion of this collection including heirloom cultivars or old breeding materials has not been systemically screened for these major sweetpotato viruses. In this study, a total of 69 so-called heirloom sweetpotato PI accessions were evaluated for their virus status. We used Real-time PCR to detect five sweetpotato viruses, including four RNA viruses (SPCSV, SPFMV, SPVG, and IVMV) and one DNA virus (SPLCV). A multiplex Real-time RT-PCR system was developed to detect three RNA viruses (SPFMV, SPVG, and IVMV). Preliminary data indicated that about 15% of these heirloom sweetpotato germplasm carried at least one of these viruses tested. Details on virus infection status will be presented.

Full access

Christian A. Wyenandt, Lisa R. Maimone, Kathryn Homa, Angela M. Madeiras, Robert L. Wick, and James E. Simon

cultivars or breeding lines for testing. Table 1. Downy mildew sporulation on leaves of basil cultivars at time of seed collection and detection of Peronospora belbahrii using real-time PCR assay on seed collected following an outbreak of downy mildew at

Free access

Jing Ma, Zheng Li, Bin Wang, Shunzhao Sui, and Mingyang Li

-μL reactions using 5 μL of Ssofast EvaGreen Supermix (Bio-Rad, Hercules, CA), 0.5 μL of each primer (500 nM final concentration), 3.5 μL water, and 0.5 μL cDNA template. Primers ( Table 1 ) for the real-time PCR were designed by Primer Premier 5

Free access

Timothy W. Coolong, Ronald R. Walcott, and William M. Randle

could allow for the prediction of storage rot based on inoculum levels at harvest. Conventional diagnostic assays do not have the capacity to reliably quantify mycelial mass in onion tissue; however, quantitative real-time PCR represents one technique by

Full access

Misaki Ishibashi, Takeshi Nabe, Yoko Nitta, and Yuichi Uno

; FAN_r1.1 ( Hirakawa et al., 2014 ) by bowtie/BWA ( Langmead et al., 2009 ). The numbers of expressed genes were estimated using RSEM ( Li and Dewey, 2011 ). cDNA synthesis and real-time PCR. A ReverTra Ace qPCR RT kit (Toyobo, Osaka, Japan) was used

Free access

Zhiyong Hu, Qing Liu, Meilian Tan, Hualin Yi, and Xiuxin Deng

, and POD genes are important in the control of lignin biosynthesis ( Boerjan et al., 2003 ; Whetten and Sederoff, 1995 ). Quantitative real-time PCR analysis indicated that the transcript abundance of the C4H gene in HRB was higher than its parents BDZ

Free access

Zhengke Zhang, Runshan Fu, Donald J. Huber, Jingping Rao, Xiaoxiao Chang, Meijiao Hu, Yu Zhang, and Nina Jiang

-length expansin gene including the complete coding region. The clone was designated as CDK-Exp3 (accession number FJ455264). Real-time polymerase chain reaction analysis. Two oligonucleotide primer pairs used for real-time PCR analysis were designed according to

Free access

Fatemeh Khodadadi, Masoud Tohidfar, Mehdi Mohayeji, Abhaya M. Dandekar, Charles A. Leslie, Daniel A. Kluepfel, Timothy Butterfield, and Kourosh Vahdati

were aligned with walnut genome sequences (A.M. Dandekar, unpublished data), using BLAST to identify the walnut version of the tomato P14a . Real-time PCR. Three replicates of whole leaf samples detached at 0, 24, 72, 96, 120, and 144 h after