Search results
Results from the WOW.Com Content Network
Pyrenophora tritici-repentis and Drechslera tritici-repentis is a necrotrophic plant pathogen of fungal origin, phylum Ascomycota. [1] The pathogen causes a disease originally named yellow spot but now commonly called tan spot, yellow leaf spot, yellow leaf blotch or helminthosporiosis.
Common Deuteromycetes that cause leaf spot disease: [7] [8] [9] Deuteromycetes Cause and Host Alternaria: Small water-soaked lesions, maturing into sunken and brown spots with or without a yellow halo. May show concentric rings with purple margins. Necrotic tissue may fall out to appear shot-holed. Leaf spot on many plants and crops. Septoria
The flowers are 5–13 mm (0.2–0.5 in) long, with 3 yellow petals and 3 yellow sepals spreading outwards. The flowers will open in the morning but typically wilt in the hot afternoon sun. When not flowering, the plant can resemble grass, but it is not a grass. [12]
The pathogens are spread by grass trimming equipment such as a lawn mower as they carry the plant debris that contains the scelerotia (13). In addition, the hyphae from an infected plant invade other nearby plants as they grow outside of roots and rhizomes (10). Black mycelium as known as “runner hyphae” grow on surface of infected roots ...
Serious infestations can cause plant death. Rose scale (order Hemiptera: family Coccoidea) Aulacaspis rosae – Mainly found on the stems and branches of the plant, lack of control will allow the pest to spread to flower stalks and petioles. At this point the plant would be stunted, spindly and with a white, flaky crust of scales on the bark.
Turf melting out begins as black to purple spots on the leaf blades. These spots eventually appear on the leaf sheaths. The fungus then begin to move down and invade the crowns and the roots of the plants. From far away, the turf appears yellow or blackish brown. The colors that appear on the turf directly reflect the nitrogen levels in the ...
Prevention is the best option for management of gray leaf spot as hyphae on plant debris is the primary source of inoculum. [1] There are various cultivars of St. Augustine grass, perennial ryegrass and tall fescue on the market that have variable resistance to gray leaf spot but none are confirmed as completely resistant.
Aster yellows is a chronic, systemic plant disease caused by several bacteria called phytoplasma. [1] The aster yellows phytoplasma (AYP) affects 300 species in 38 families of broad-leaf herbaceous plants, primarily in the aster family, and important cereal crops such as wheat and barley.