How do phythophtora infestans reproduce

Phytophtora infestans is host-specific pathogen and can reproduce both asexually and sexually.

Explanation:

Asexually: The spores (sporangia) of P. infestans are transported via wind or water. Once they land on the plant tissue, the zoospores are released. When conditions are warmer, zoospores are germinated. Here, a germ tube is formed which penetrates into the plant tissue and allows the newborn to get nutrients from plant sap for its own growth and development.

Sexually: Sexual reproduction takes place when both male and female are present. Here, antheridium and oogonium nuclei (haploid) fuse together to form a diploid oospore. The oospore then develops into sporangium and the rest of the cycle follows the same pattern as of asexual reproduction.

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.