ਝੋਨੇ ਦੇ ਦਾਣਿਆਂ ਦੀ ਕਾਲਖ ਦਾ ਰੋਗ
#ricesmut #ricebunt #kernelbunt #jhona #bimari #surma #danapatakamarna
ਝੋਨੀ ਦੇ ਦਾਣੇ ਦੇ ਵਿੱਚੋਂ ਸੁਰਮਾ ਜਿਹਾ ਨਿਕਲਦਾ ਹੈ ਢੇਰੀ ਵਿੱਚ ਪਿਆ ਝੋਨਾ ਪਟਾਕਾ ਮਾਰੀ ਜਾਂਦਾ ਹੈ ਇਹ ਕੀ ਬਿਮਾਰੀ ਹੈ ਕੀ ਇਸਦਾ ਕੋਈ ਇਲਾਜ ਹੋ ਸਕਦਾ ਹੈ ਕਿਵੇਂ ਬਿਮਾਰੀ ਤੋਂ ਬਚਾ ਕਰਨਾ ਹੈ
Symptoms
Kernel smut appears as a black mass of chlamydospores that replace all or part of individual kernels near or at maturity. Usually only a small number of kernels on each panicle are infected. Completely smutted kernels may be slightly swollen while others may break open exposing the dark spores. These black spores make the disease easy to recognize. If the disease is severe, a dark cloud of spores may be observed coming from the harvester during harvest.
Comments on the Disease
Chlamydospores liberated during harvest fall to the soil where they overwinter. The fungus can also overwinter in or on seeds. In spring as the fields are flooded, chlamydospores float, germinate, and produce other spore and mycelial stages. At flowering (heading), secondary airborne spores (sporidia) infect individual florets or kernels.
Kernel smut is generally considered a minor disease of rice. In southern U.S. rice growing areas, it is more prevalent during rainy years and in areas of fields receiving high rates of nitrogen fertilizer. Disease surveys have shown short and medium grain varieties to have lower incidence rates for kernel smut than long grain varieties. Long grain rice varieties may be more susceptible to kernel smut because their florets are open wider and longer during flowering. Because the fungus is widespread in California's rice growing areas, no effort has been made to restrict infested seed lots.
Management
Cultural practices are the primary means of managing kernel smut. Chemicals for controlling this disease are not registered for use on rice in California at this time.
Cultural Control
Avoid excessive rates of nitrogen fertilizer. Plant short or medium grain varieties in fields with kernel smut history. Plant certified rice seed.
Kernel smut of rice (Tilletia horrida) is an exotic plant pest not present in Australia. This disease is a serious threat to Australia’s rice industry.
Notifiable status
Kernel smut of rice (Tilletia horrida) is a notifiable plant disease in NSW.
All notifiable plant pests and diseases must be reported within 1 working day. You can report notifiable plant pests and diseases by one of the following methods:
Call the Exotic Plant Pest Hotline 1800 084 881
Email biosecurity@dpi.nsw.gov.au with a clear photo and your contact details
Complete an online form
A full list of notifiable plant pests and diseases can be found in Schedule 2 of the NSW Biosecurity Act 2015.
Description
Kernel smut of rice is caused by the fungus Tilletia horrida synonym Neovossia horrida.
Kernel smut of rice reduces grain quality by producing black, sooty masses of powdery spores which replace all or part of the grain (Figure 1). Some strains of the fungus produce toxins which taint milled grain.
Symptoms
Kernel smut of rice is most evident at crop maturity. Black masses of spores replace the grain and burst out through the hulls (Figure 2).
Dislodged spores from infected grains settle on other plant parts forming a characteristic black dusty coating. During harvest black clouds of spores can be released into the air and cover the machinery and equipment.
Lifecycle
The fungus survives as spores in the soil and in infected seed. Germinating spores infect immature developing rice grains. The fungus replaces the endosperm of the grain with a mass of black spores.
The kernel smut of rice fungus is not systemic. Flowers are infected individually by wind-borne spores and only a few florets in a panicle may be infected.
Hosts
Kernel smut infects rice (Oryza sativa) and grasses in the genera Brachiaria, Digitaria, Eriochloa, Panicum and Pennisetum.
Spread
Wind-borne spread of kernel smut of rice spores infects and reinfects rice panicles both within a crop and into neighbouring crops.
Long distance spread occurs when spores of the fungus are transported on infected and contaminated grain, machinery and equipment.
Spores of kernel smut of rice are able to float on water and may be spread this way.
Distribution
Kernel smut of rice occurs in most rice producing countries including Burma, China, India, Indonesia, Japan, Korea, Mexico, the Philippines, Senegal and the USA.
Kernel smut of rice is not present in Australia.
Actions to minimise risks
Put in place biosecurity best practice actions to prevent entry, establishment and spread of pests and disease:
practice “Come clean, Go clean”
ensure all staff and visitors are instructed in and adhere to your business management hygiene requirements
source propagation material of a known high health status from reputable suppliers
keep records
16 сен 2024
