Best Viewed in Mozilla Firefox, Google Chrome

Production Know How

Production Know How
8
May

VIKRAMARYA

File Courtesy: 
Directorate of Rice Research, Hyderabad
8
May

Chemical control of Rice Tungro Virus vector

The spread of rice tungro disease can be checked indirectly by controlling the vector by suitable pesticide application. As the plants are more vulnerable to RTV infection during early stages of growth, chemical protection of the nursery effectively reduces green leafhopper population and thereby minimises the build up of virus inoculum as well as the pace of transmission.

Nursery Protection

File Courtesy: 
Directorate of Rice Research, Hyderabad
8
May

Use of resistant variety for RTV

Tungro virus can not be directly controlled by applying any chemical. The best method of preventing tungro is to grow resistant varieties. A variety may be resistant to virus or the insect vector or to both virus and insect vector.
VIKRAMARYA, developed at Directorate of Rice Research, Hyderabad is the resistant variety now available for general cultivation. Other promising resistant medium duration cultures include: IET 9994, IET 8560 and IET 8565 with slender grains and IET 8902 with long bold grains.

File Courtesy: 
Directorate of Rice Research, Hyderabad
Photo Courtesy: 
Directorate of Rice Research, Hyderabad
8
May

Mode of transmission of RTV

When young (nymphs) and adult green leafhoppers feed on diseased plants, virus particles get attached to mouth parts (stylets). As these insects fly and feed on other plants, the virus particles from the stylets get introduced into healthy plants. The insects pick up virus particles within 5 minutes of feeding and can transmit these particles to other healthy plants. The green leafhoppers can not retain virus for a long time. They acquire virus again through repeated feedings. Generally, 8 -10 days after such an introduction of virus in plants, tungro virus disease symptoms appear.

File Courtesy: 
Directorate of Rice Research, Hyderabad
Photo Courtesy: 
Directorate of Rice Research, Hyderabad
8
May

Symptoms of Rice Tungro Virus (RTV)

RTV can appear at any time on rice right from seedling stage. The extent of crop damage and yield loss depends on the growth stage at the time of RTV infection.

File Courtesy: 
Directorate of Rice Research, Hyderabad
Photo Courtesy: 
Directorate of Rice Research, Hyderabad
8
May

Tungro Disease in Rice

Rice Tungro Virus (RTV) is a destructive disease of rice. Incidence of RTV in India was first observed at West Bengal in 1966 and two years later, appeared extensively in eastern Uttar Pradesh and northern Bihar inflicting heavy crop losses. Subsequently, RTV has been observed occasionally in parts of Andhra Pradesh, Assam, Bihar, Kerala, Pondichery, Tamil Nadu, Uttar Pradesh and West Bengal. In Andhra Pradesh, incidence of RTV has been recorded often at low to moderate severity since 1976.

File Courtesy: 
Directorate of Rice Research, Hyderabad
27
Aug

Other novel pest control techniques (Insect Sex Pheromones)

1. Semio-chemicals are chemicals involved in communication

File Courtesy: 
Technical Bulletin No. 10, Integrated Pest Management in Rainfed Rice Production Systems, Directorate of Rice Research.
27
Aug

Biological Control of Pests in Rice

1. Exploitation of biological agents such as parasites,

predators and pathogens is a key component of rice IPM and can be a promising alternative to ecologically disruptive chemical control measures.

2. Inundative or inoculative releases of the egg parasitoid, Trichogramma japonicum ashmead against yellow stem borer and T. chilonis Ishii against leaf folder are effective and economical.

File Courtesy: 
Technical Bulletin No. 10, Integrated Pest Management in Rainfed Rice Production Systems, Directorate of Rice Research.
26
Aug

Chemical Control

1. Despite the drawbacks involved in insecticide

usage in rainfed rice systems, the farmers readily use pesticides in times of sudden pest outbreaks. 

2. During such times, there is a need to choose the right insecticide formulation and dose as well as suitable application technique based on pest biology and crop phenology. 

File Courtesy: 
Technical Bulletin No. 10, Integrated Pest Management in Rainfed Rice Production Systems, Directorate of Rice Research.
26
Aug

Appropriate cultural methods

Cultural practices are normal agronomic practices

followed for increasing crop productivity and their appropriate manipulation can effectively prevent the insect pest populations from causing losses to the crop.

File Courtesy: 
Technical Bulletin No. 10, Integrated Pest Management in Rainfed Rice Production Systems, Directorate of Rice Research.
26
Aug

Growing resistant varieties

1. Resistant cultivars are the most effective,

economical and practical means of encountering the pest problems and compatible with all components.

2.  In India, among the 710 commercial rice varieties released, 51 varieties are resistant to gall midge, 25 to brown planthopper, 3 to stem borer and green leafhopper and whitebacked planthopper. 

File Courtesy: 
Technical Bulletin No. 10, Integrated Pest Management in Rainfed Rice Production Systems, Directorate of Rice Research.
26
Aug

Components of rice IPM

Components of rice IPM include

I. Growing resistant varieties.

II. Growing resistant varieties.

III. Chemical Control

IV. Biological Control

V. Other novel pest control techniques (Insect Sex Pheromones)

 

File Courtesy: 
Technical Bulletin No. 10, Integrated Pest Management in Rainfed Rice Production Systems, Directorate of Rice Research.
26
Aug

Integrated Pest Management

1. Integrated Pest Management (IPM) is the most appropriate approach to obtain sustainable rice yield with least damage to the environment. 

2.  Integrated pest management in the simplest terms is referred to as “a broad ecological strategy combining several components such as insect resistant rice varieties, cultural, chemical and biological control methods for the management of insect pest populations below the levels at which they cause economic injury to the rice crop.

File Courtesy: 
Technical Bulletin No. 10, Integrated Pest Management in Rainfed Rice Production Systems, Directorate of Rice Research.
26
Aug

Reporting

Calculate the following data to characterize the performance of the dryer: 

1. Average and standard deviation of the moisture content before and after drying.  

2. Total weight loss of paddy

3. Drying rate (%/h)

4. Increase in broken grain (i.e. percentage of broken grains before drying minus percentage of broken grains after drying)

5. Increase in cracked grain (i.e. percentage of cracked grains before drying minus percentage of cracked grains after drying)

6. Electric power consumption/Fuel consumption

File Courtesy: 
http://www.riceindia.net/RKBank/Training_Manual_Paddy_Drying.pdf
26
Aug

Drying test

1.Paddy of a known source should be selected with grain moisture content that is typical for grain harvested in the area. 

2. The paddy should be cleaned to remove very few impurities (straws, etc).

2. Before loading the materials, mix the paddy and take at least 10 samples of the paddy of 10g each to determine variance in moisture content. 

3. In addition, sample of 500g of wet paddy is taken for laboratory analysis. If possible, take the entire weight of the paddy before loading.  

File Courtesy: 
http://www.riceindia.net/RKBank/Training_Manual_Paddy_Drying.pdf
26
Aug

Evaluation of grain dryers

1. After purchase or instalment of a grain dryer it is important to evaluate its performance.  

2. This is usually done by conducting a drying test. 

3. Drying tests are important because actual performance data are often different from rated performance that is provided by the manufacturer. 

File Courtesy: 
http://www.riceindia.net/RKBank/Training_Manual_Paddy_Drying.pdf
26
Aug

Troubleshooting

1. A drying system can only maintain quality but it cannot improve the quality of paddy. 

2. When a dryer produces poor quality paddy it is therefore important to compare the paddy from the dryer with a reference sample from the same batch that was dried under controlled conditions, e.g. in an air-conditioned room, or in the shade by spreading a thin layer and frequently mixing.

3. Otherwise it is difficult to tell whether the low quality is caused by quality reduction that occurred before drying, e.g. during field drying, or in the drying system.

File Courtesy: 
http://www.knowledgebank.irri.org/rkb/index.php/examples-ofdryers/troubleshooting
26
Aug

Conclusions for Economic Feasibility Studies

Considering the issues in the last two sections the following recommendations for economic analyses of mechanical drying can be made: 

1. Investing in a dryer for saving the crop. 

2. The problem is that in this case the fixed cost component of the drying cost (depreciation) per batch is very high because the dryer is only used in emergency, meaning a few times a year.

3. A dryer used only in emergency cannot be used economically.

File Courtesy: 
http://www.riceindia.net/RKBank/Training_Manual_Paddy_Drying.pdf
26
Aug

Cost of drying

1. Case studies in Asian countries indicate that mechanical dryers with cost higher than 5% of the paddy value cannot be introduced successfully.

2. There is no point in listing cost numbers for different drying systems here since drying cost depends on many site specific factors and a “business plan” including a cost-benefit calculation is needed for each individual drying system considering the conditions of the locality.

File Courtesy: 
http://www.riceindia.net/RKBank/Training_Manual_Paddy_Drying.pdf
26
Aug

Weight loss in drying

1.During the drying process water is removed from the grains .

2. That means that after drying, paddy weight is lost and the dried paddy is to be sold since in most markets paddy is traded on a weight basis.

3. In markets, where paddy is still traded on a volume basis there is a similar effect since paddy shrinks in volume during drying also. 

File Courtesy: 
http://www.riceindia.net/RKBank/Training_Manual_Paddy_Drying.pdf
Syndicate content
Copy rights | Disclaimer | RKMP Policies