Jacela, Lois Daniel M. <br/><br/>
Molecular detection of Sigatoka disease complex of banana in Cavite State University, Indang, Cavite / 
by Lois Daniel M. Jacela. 
 - Indang, Cavite :  Cavite State University- Main Campus,  2019. 
 - xv, 85 pages :   illustrations ;  28 cm. 
<br/><br/> Thesis (Bachelor of Science in Agriculture Major in Crop Science) Cavite State University. 
<br/><br/>Includes bibliographical references. 
<br/><br/>College of Agriculture, Food, Environment and Natural Resources (CAFENR), Department of Crop Science  College of Agriculture, Food, Environment and Natural Resources (CAFENR), Department of Crop Science 
<br/><br/> JACELA, LOIS DANIEL M. Molecular Detection of Sigatoka Disease Complex of<br/>Banana at Cavite State University, Indang, Cavite. Undergraduate Thesis. Bachelor of<br/>Science in Agriculture (Major in Crop Science). Cavite State University, Indang, Cavite.<br/>January 2019. Adviser: Dr. Hosea dL. Matel.<br/><br/>This study was conducted from January to October 2018 at the Research Center and<br/>Central Experiment Station of Cavite State University Indang, Cavite. This study aimed to (1)<br/>assess disease severity of banana infected with Sigatoka Disease Complex (SDC) in Cavite<br/>State University Indang, Cavite, (2) isolate fungal cultures from banana leaves with SDC and<br/>determine fungal morphology through microscopic evaluation, (3) determine the<br/>symptomatology of SDC in the locality, and (4) identify through PCR based detection the<br/>presence of (a) Pseudocercospora fijiensis, (b) Pseudocercospora musae and (c)<br/>Pseudocercospora eumusae.<br/>Different areas planted with banana in CVSU, Indang, Cavite were assessed for the<br/>disease severity of SDC: Central Experiment Station (CES), SAKA, EBA farm and Coffee Gene<br/>Bank. Disease severity in the CES was 59%, 40% for SAKA, 31% for EBA farm and 30% for<br/>Coffee Gene Bank.<br/>Three microbial isolates were purified from 3 mm SDC-infected banana leaf sections by<br/>sub-culturing on PDA plates. Fungal morphologies were observed through binocular<br/>microscope, from slide culture preparation and after heat-fixing and staining of the cultures<br/>using lactophenol cotton blue and crystal violet. Two of the isolates showed septate conidia with<br/>clear color, while the ascospore was clear in color and have only one septum. The fungal<br/>morphology for these two isolates resembles that of P.fijiensis. The other isolate showed<br/>absence of septum in the conidia.<br/>DNA was extracted from three purified isolates and subjected to Polymerase Chain<br/>Reaction (PCR). Gradient PCR was used to optimize the annealing temperature of the primer<br/>that was previously used for the detection of the SDC. Annealing temperature of 61 oc and 63<br/>0C were suitable in producing good PCR product. Through PCR, 500bp amplicon size was<br/><br/>observed for gene specific primer pair ACTR/MFactF, which was the expected amplicon size<br/>for P. fijiensis.<br/>One of the isolates was further confirmed as P. fijiensis through demonstration of Koch's<br/>postulate. Inoculation of healthy banana leaves with the isolate showed symptoms associated<br/>with SDC after fourteen days of inoculation. The disease progressed to late stage after fifty<br/>days of inoculation showing large black lesions surrounded by yellow halo. These similar<br/>symptoms were observed in the field among SDC-infected bananas.<br/>PCR based method confirmed the presence of Black Sigatoka Disease in banana growing<br/>areas in Cavite State University, Indang Cavite. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Pests and diseases<br/>Plants, Protection of<br/>Bananas--Disease and pest resistance
<br/><br/><label>Dewey Class. No.: </label>634.772   / J11 2019