In the dry season, rice pests and diseases which generally arise based on the severity level is mice, followed by stem borers, and walang rice pest. Therefore, measures focused on pest control mice.
In the rainy season, pests and diseases that usually arises is the rat, brown plant hopper, stem borer, stone javelin, tungro disease, blast, bacterial leaf blight, and other diseases caused by fungi. In special circumstances, pests and diseases are growing out of the ordinary. For example, in a wet dry season, BPH can also be a problem for susceptible varieties (Hendarsih et al. 1999).
Stadia Plants
In the fallow period, stem borer larvae are inside singgang and sometimes singgang tungro virus infection, and other diseases caused by bacteria-kan. In the hay can also be found sklerotia of several fungal diseases. Mice could be in the midst of other plants or hiding in irrigation dikes. On land that is wet, snails can also be found. All pests and diseases during fallow can be a source of pests and diseases in the next planting.
In the nursery can be found mice, stem borer, green leafhopper, tungro infected seedlings, and the golden apple snail eggs. Pests and diseases of the vegetative stage is the golden apple snail, Ganjur, hidrelia, mice, stem borer, brown plant hopper, leaf roller pests, armyworm, javelin stone, tungro, bacterial leaf blight and leaf blast. In the generative stadia usually mice, stem borer, brown plant hopper, leaf roller pests, armyworm, walang rice pest, javelin stone, tungro, bacterial blight, blast neck and various diseases caused by fungi.
Rice Cultivation
Rice cultivation in productivity improvement efforts to influence the presence of pests and diseases. Tillage, weeding and singgang, balanced fertilization, spacing, watering, and maintenance of fish may reduce some pest and disease attacks rice. Intermittent irrigation besides increasing yields also reduce rice disease. But rice cultivation could also have the opposite effect of the double, ie on the one hand improve yields, on the other hand to stimulate the development of pests and diseases. Introduction of high yielding varieties in early 1970 has been a high increase rice production, but an explosion in the decade of 70s BPH is thought to occur due to the adoption of high yielding varieties are susceptible to brown planthopper and responsive to fertilization (Mochida et al. 1980). Similarly, the explosion of white rice stem borer in 90s, thought to be caused by the extent of crop and climate deviations IR64 (Hendarsih et al. 2000).
Natural Enemies
For rice cultivation lot of useful organisms that can suppress populations of pests and disease pathogens. Different types of spiders are very useful in a variety of insect pests prey (Widiarta et al. 2001). Besides functioning parasitoids suppress insect pest populations increase. Brown planthopper egg parasitoid Anagrus spp. and Oligosita spp. blast hit the brown planthopper function naturally. Also in the field are antagonistic bacteria that can suppress fungal leaf sheath blight disease (Sudir and SUPARYONO 2000). Many entomopathogenic unconsciously come to control insect pests, and can be bred for biological control.
Control Measures
Control over the types of pests can cause native populations are not important. Ganjur explosion in North Beach in the 1970s Jatilahur allegedly due to incessant aerial spraying of pesticides since 1968. Some insecticides was very toxic to many animals, including natural enemies population is depressed, so the pest population continues to grow and turn into pests that are resistant to insecticides in question. Some not only broad-spectrum insecticides (broad spectrum) but also trigger the development of population (resurgence). This happens on brown planthopper, thus giving birth inpress No.. 3 th, 1986, about the ban 57 types of insecticides. Adoption of resistant varieties is the most secure way to control the environment. However, if a resistant variety is grown continuously on large areas that will lead to changes in pest biotypes or pathogen races disease. For the brown planthopper, change toward a more virulent biotypes take place very quickly, because most varieties resistant genes regulated by monogenic. Pressure on planthopper population is so high that quickly turned into a more virulent biotypes. GLH quickly adapt to new varieties so that in some time the growing season, varieties previously not infected with tungro tungro be vulnerable, because nature is the resilience of the green leafhopper resistant. Varieties for blast resistance quickly become vulnerable, because of race blast in a rapidly changing field and adjust to the new varieties diintrodaksi. The extent of crop varieties IR64 cause severe infected by bacterial leaf blight. Thus known that the control of pests and diseases can not rely on one method of control.
Cropping patterns
On the technical irrigated area, irrigation can be set so that the time of planting and planting time can be determined simultaneously. Synchrony of planting can reduce the attack of various pests and diseases. Control of tungro with proper planting time and rotation resistant varieties can be applied to crop land simultaneously as in South Sulawesi (Sama et al. 1991). Planting on land not in unison, after the rainy season crops most vulnerable to drought severe pest and disease, especially after cropping MK II. Pests and diseases that could potentially explosive during the rainy season after a drought is brown planthopper and tungro. Failure of the control mice at two previous growing season would exacerbate rat infestation during the rainy season. When planting in the MK II, there will be accumulation of population. In these conditions the success of the control rats during the rainy season (before MK I) have an impact on the success of the control rats on MK I and MK II, then continued during the rainy season. If the control mice at the beginning of the rainy season before the drought is not good, it will cause a chain failure until after the rainy season drought.
In some places, although technically irrigated due to the limited water allocations or farmer groups less running, time of planting to be not simultaneous. In the cropping pattern is not simultaneous, pests that need to be observed is the rat, especially in the dry season. The lack of simultaneous planting provides an opportunity for rats to reproduce (breeding period) within a longer time. In addition, controlling the rotation of varieties based tungro resistance to green leafhopper less successful because there is always a crop of young, developing green leafhopper place transmit tungro virus.
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