The key difference between pythium and phytophthora is that Pythium is a genus of oomycetes that are mostly pathogens of monocotyledons while Phytophthora is a genus of oomycetes that are mostly pathogens of dicotyledons.
Oomycetes are a group of aquatic and terrestrial eukaryotic microscopic organisms which are filamentous. They resemble fungi. Furthermore, similar to fungi, they reproduce sexually as well as asexually. Oomycetes are often animal and plant pathogens. Moreover, they cause significant environmental and economic damage. Pythium and Phytophthora are two parasitic oomycetes, hence pathogens. They both belong to order Peronosporales of phylum Heterokontophyta.
CONTENTS
1. Overview and Key Difference
2. What is Pythium
3. What is Phytophthora
4. Similarities Between Pythium and Phytophthora
5. Side by Side Comparison –Pythium vs Phytophthora in Tabular Form
6. Summary
What is Pythium?
Pythium is a genus of oomycetes. There are more than 200 Pythium species living in terrestrial and aquatic habitats. They belong to phylum Heterokontophyta that includes eukaryotic filamentous microscopic organisms. Structurally, Pythium has coenocytic hyphae, which are aseptate. Cellulose is the main component in their cell walls. Pythium reproduces using both asexual and sexual methods. During asexual reproduction, they produce chlamydospores, which are thick-walled spores. In contrast, during sexual reproduction, they produce antheridia and oogonia.
Figure 01: Pythium
Many Pythium species are plant parasites. They cause a variety of diseases to plants, especially to monocotyledons plants. Most importantly, Pythium is not very host specific. Hence, they have a vast range of host species. Root rot is a prominent disease caused by Pythium. Moreover, they cause Pythium blight of turf, and damping-off, which involve seed rot and pre- and post-emergence seedling death. Moreover, there are saprophytic Pythium species and animal pathogenic Pythium species.
What is Phytophthora?
Phytophthora is another genus that belongs to order Peronosporales of phylum Heterokontophyta. This genus comprises more than 80 species. Similar to Pythium, Phytophthora also has aseptate hyphae. Moreover, their cell walls contain cellulose. One of the characteristic features of Phytophthora is the production of zoospores.
Figure 02: Phytophthora
Majority of Phytophthora species are plant pathogens. They cause late blight of potato and tomato, foliar blights on peppers and cucurbits, and root or stem rots of many plant species. Most pathogens that cause kiwifruit root rot are species of Phytophthora. Some Phytophthora species are foliar pathogens and cause a serious threat to forests and nurseries.
What are the Similarities Between Pythium and Phytophthora?
- Pythium and Phytophthora are two parasitic oomycetes.
- They belong to order Peronosporales of phylum Heterokontophyta.
- Both Pythium and Phytophthora have aseptate hyphae.
- Their cell walls contain cellulose as the main component.
- Both oomycetes produce chlamydospores during asexual reproduction.
- Moreover, they produce oogonia and antheridia during sexual reproduction.
What is the Difference Between Pythium and Phytophthora?
Pythium and Phytophthora are two parasitic oomycetes genera. Pythium primarily attacks monocotyledon plants causing root rot, while Phytophthora primarily attacks dicotyledons causing damping off and root rot. So, this is the key difference between Pythium and Phytophthora.
Moreover, Pythium species tend to be very generalistic and unspecific in their large range of hosts, while Phytophthora species are generally more host-specific. Therefore, this is another difference between Pythium and Phytophthora.
Below infographic provides more information regarding the difference between Pythium and Phytophthora.
Summary – Pythium vs Phytophthora
Pythium and Phytophthora are two genera of parasitic oomycetes that cause root rot in many plants. Pythium attacks monocotyledons primarily. In contrast, Phytophthora attacks dicotyledons. Thus, this is the key difference between Pythium and Phytophthora. Furthermore, Pythium is a fast-growing eukaryote, while Phytophthora is a slow-growing eukaryote. Moreover, Pythium is not very host specific, while Phytophthora is host specific. Thus, this summarizes the difference between Pythium and Phytophthora.
Reference:
1. “What Is Pythium? (Pythium).” Pythium (Penn State University), Available here.
2. “Phytophthora Basics.” Phytophthora Basics | Forest Phytophthoras of the World, Available here.
Image Courtesy:
1. “Pythium (257 23)”By Doc. RNDr. Josef Reischig, CSc. – Author’s archive (CC BY-SA 3.0) via Commons Wikimedia
2. “Phytophthora infestans potato Parel, aardappelziekte Parel” By Rasbak – Own work (CC BY-SA 3.0) via Commons Wikimedia