Philippine E-Journals

Developing Morphological and Simple Sequence Repeats Markers for Putative Drought Tolerant Papayas

Pablito M. Magdalita | Alangelico O. San Pascual

 

Abstract:

Drought as a result of climate change has adverse effects on plant production. It is known to negatively impacted food production. One important crop in the Philippines which is affected by drought is papaya. Papaya ringspot virus (PRSV) and bacterial crown rot (BCR) are two other pressing problems of this crop. Under drought conditions in the field, papaya showed decrease productivity as it produces smaller and fewer fruits but had sweeter flesh. Ten papaya genotypes were selected as putative drought tolerant. The basis for drought tolerance is their relative growth rate in terms of plant height, stem diameter, the chlorophyll content of leaves, and a number of closed stomata during the imposition of drought. Compared to drought susceptible genotypes, putative drought-tolerant papaya genotypes have more closed stomata, higher chlorophyll content, bigger stem, and crown diameter, and have a greater number of leaves. To mark the putative drought-tolerant selections, Screening of 21 simple sequence repeats (SSR) primers to reveal polymorphism among 15 genotypes was done. Polymorphic bands were consistently revealed by 5 SSR primers across 15 genotypes. From the 21, 2 SSR primers have been selected to mark putative drought tolerant genotypes.