One of the problems in rice cultivation is rice plants that we plant attacked by diseases, many types of diseases that attack rice plant one of which rice blast disease, we know that plants attacked by blast disease the average will decrease productivity of the rice harvest. The cause of the blast disease is a plant attacked by fungi Pyricularia grisea, beginning occurrence of blast disease occurred on upland rice cultivation and until now spread to irrigated rice.
Blast disease in lowland rice can attack at all stages of growth, even in rice seeds have started to infected blast disease, whereas to attack blast disease attacking phase of seeding until the phase of the harvest, because its growth is very fast then and you may never find a case when rice stay enter the flowering phase sudden attacked by severe disease or attacked by blast diseases which causes the of rice grains are not filled. For stage critical attack blast disease is when the rice 1 month old (upland rice), when the rice plants entering the maximum tillering, when entering it contains, and the last time the rice plants into early flowering, this is the critical condition of the attacks to blast disease, it is just a suggestion on this phase you are more often observe your rice crops in rice field, to be minimized or mitigated attack could blast disease more severe.
Biology and Blast Disease Ecology
Blast disease from the data IRRI in 1975 already 250 race / variant genetic blast disease, so can you imagine for a year now how many more races from blast disease that appears and attacks the rice plant, paddy blast disease will be very fast in forming a new race when plant populations and plant resistance to change. When environmental conditions supporting one rice blast disease cycle need only take about 1 week and very easily spread through the air, the cycle starts from spores fungi that infect plants then produce leaf spot in rice plants, and the cycle is ended until sporulation to spread its spores a new one through the air. And from here from one spot on the infected leaves will grow and produce spores new mushroom into hundreds to thousands in one night, from where that sometimes makes farmers amazed and confused because the spread blast disease very fast, especially attacks blast disease with increasing spore mushrooms that will last up to 20 days and can even more.
Contagion blast disease usually occurs through conidia on the wind, conidia will be formed and released at night, or you needs to alert if there is a sudden rain during the day and then hot again, because to the condition air relative humidity of more than 90% then konidium this will be released explosively, penetration of fungal spores usually occurs directly and penetrate kultikula on the upper surface of the leaves and will be easier to penetrate the leaves are still young. Mushrooms P.oryzae can defend themselves on the remnants of plants including rice straw and rice blast disease will survive in the form of mycelium or konidium.
Symptoms Attacks Blast Disease
Symptoms of rice blast disease can indeed attack on the leaves, stems, panicles, and rice, but symptoms of blast disease is classified into two categories, including:
- Blast leaves, blas leaf attack plants rice during the vegetative phase with symptoms such as spots that have an oval or elliptical both ends tapered similar to a rhombus, center spotting has gray color or whitish and usually have the edge at spotting brown or reddish-brown.
- Neck root, neck rot attacks the rice plants when the generative phase with typical symptoms is rotten end of the stem panicle stalk from panicles experience rot makes stalk panicle easily broken that resulted of rice grains are not filled and empty. In rice sick you can also detect the emergence of small patches that round.
Blast disease control strategies
Control strategies or rice blast disease management that you can do there are two ways, the first is how to control blast disease pre - emptive ie controlling before being discovered attack blast disease, the second by way responsive rice blast disease control by using fungicides, for more details, I described as follows this.
Control strategies or rice blast disease management that you can do there are two ways, the first is how to control blast disease pre - emptive ie controlling before being discovered attack blast disease, the second by way responsive rice blast disease control by using fungicides, for more details, I described as follows this.
How to controlling blast disease pre - emptive
- Burning rice straw former diseased plants to reduce the source of infection.
- You can plant a spacing that has good air circulation, this is done to give environmental conditions a less supporting for the spread blast disease.
- Do not use a fertilizer with N elements in excess, to the use fertilizer N is not more than 90 kg / ha and always apply a balanced fertilizer.
- Award husk ash, husk ash Award in rice cultivation area is expected to increase the content silicates in rice plants.
- Planting rice simultaneously, if you can avoid late rice planting time with cultivation of rice in the surrounding areas.
- Avoid planting time where by the time out panicles and early flowering there are a lot of dew.
- Do not use seeds from endemic areas blast disease.
- The use of rice varieties resistant blast disease.
- Control by the time seed treatment with soaking using biological agents such as Pseudomonas flourescens and Paeni baccilus.
Blast disease control with fungicides
The use of fungicides in controlling blast disease you can do by using a fungicide active ingredient among others: Azoxistrobin: 200 g / l + difenokonazoi, Trisiklazol: 200 g / l, Isoprotiolan: 400 g / l, Propikonazol: 125 g / l + Trisiklasol: 400 g / l, Kasugamisin: 20,8 g / l, Metiltiofanat 500 g / l, Asam Chloro Iso Bromo Sianurik 50%, Benomil 50%, Heksanazol 50 g / l, Difenokonazol: 125 g / l + Propikonazol: 125 g / l, Heksanazol 50 g / l, Simoksanil: 29,0% + Famoksadon: 22 , 5%, Trisiklazol: 75%, Metiltiofanat: 70%, Tebukonazoi: 50% + Trifloksistrobin: 25%, Tembaga Oksida: 86%.
The use of fungicides in controlling blast disease you can do by using a fungicide active ingredient among others: Azoxistrobin: 200 g / l + difenokonazoi, Trisiklazol: 200 g / l, Isoprotiolan: 400 g / l, Propikonazol: 125 g / l + Trisiklasol: 400 g / l, Kasugamisin: 20,8 g / l, Metiltiofanat 500 g / l, Asam Chloro Iso Bromo Sianurik 50%, Benomil 50%, Heksanazol 50 g / l, Difenokonazol: 125 g / l + Propikonazol: 125 g / l, Heksanazol 50 g / l, Simoksanil: 29,0% + Famoksadon: 22 , 5%, Trisiklazol: 75%, Metiltiofanat: 70%, Tebukonazoi: 50% + Trifloksistrobin: 25%, Tembaga Oksida: 86%.
That's my short article about the blast disease and how our strategy in controlling blast disease. This information I got when getting training from the department of agriculture at my place, and I hope this short article can be useful for those who had stopped by to visit and read my writing this brief, and I also invite you to share this information with other farmers to be more helpful. And lastly thanks and I'm sorry if there are writings or sentences that are less pleasing to the readers.