Pest and Disease on Plants Organs

Pest and Disease on Plants Organs

            Pest and plant diseases are two problems that attract our attention because of their negative effects to human. Pest is an animal which causes damage to agriculture. An animal is considered as a pest when the amount of individual population causes economic losses. The effect of pest on agriculture are causing damage on plants and declining the result of the harvest so that it causes the farmers suffer loss. Pest damage by eating or sucking the sap of the plant tissue.

Some Animals that are Potential to be Pests in Indonesia

No.	Animal Species	Attracted Plants
1.	Squirrel ( Callosciurus notatus )	Coconut fruit
2.	Tree sparrow ( Passer montanus, Oates )	Rice and seed of other grasses
3.	Fruit bat ( Cynopterus sphinx , Vahl )	Fruit and flower nectar
4.	Green stink bug ( Nesara viridula, L. )	Second crop ( suck on the juice )
5.	Rhinoceros beetle ( Xylotrupes Gideon, L.)	Coconut stem apex

            Plant disease is an abnormality on plants caused by pathogen organism and disturbance of environmental factors which leads to the damage of the plants. Plant disease caused damage or abnormality in absorbing and transporting food, mineral, water, food synthesize or other metabolic process disturbance that influence the appearance ( quality )and the yield of crops (quantity ). Disease causing agent on plants can be in the form of biotic and abiotic agent.

The biotic agent ( biology ) is pathogenic organism, especially bacteria, fungi, virus, parasitic plant, and nematode worm. Pathogenic organism causes disease by :

1.       Absorbing food or cell content continuously that makes the host week.

For examples are bacteria, parasitic plant, nematode, and virus.

2.       Killing cell or causing damage on metabolic activity of host cell by secreting substances, such as enzyme or toxin into the host cell.

For examples are fungi that cause wither on leaf of potato and fungi that cause corn seed smut .

3.       Disturbing transportation of food, mineral, and water on host vascular tissue.

For examples is fungi that cause wither on leaf of tomato.

4.       Preventing photosynthesis process.

 The following are several factors considered as biotic agents.

1)       Extreme temperature, such as very hot or very cold

2)       Too much or too little water

3)       Low or high light intensity

4)       Insufficient amount of nutrients

5)       Too acid or too alkaline soil

6)       Poisonous chemical drugs, such as insecticide fungicide, nematicide, molusicide, and another pesticide.