The Rice Plant
No one can lay claim solely for discovering or developing rice as food source or as an ingredient for many preparations for food and its other uses. Rice has existed since ancient times in many countries.According to published reports, rice has been used and consumed by man as early as 4,000 years ago or even older. Archeologists have discovered grains of rice buried deep on the ground in certain places in China. When the rice grains were subjected to studies, they were found to be more than 4,000 years old.
Studies also indicate that rice originated in several places in a broad area that covered Northern India, Myanmar, Thailand, Laos, Vietnam up to China.
In the Philippines, rice cultivation started thousands of years ago. In fact, the rice terraces in Banaue which were built some 3,000 years ago, were constructed by the people specifically for the cultivation of rice.
Of course, the rice that we know today may not be the same rice that was known to the early people of the world. But just the same, then as it is now, rice played an important role in human history. There is no indication that rice will be less important in the lives and culture of people who depend on them in the future.
Rice Plant: The versatile grass
The rice plant is a grass. But it is a very versatile plant and most important to most of mankind.
Without this plant, hundreds of millions of people will die because it is their staple food. Many countries of the world and even entire civilizations may eventually disappear if there are no rice plants.
This is the reason why this plant must be given very high regard, importance and attention. Everyone must consider giving help in different ways in order to provide the good conditions it needs to grow well and develop in order to provide what is most needed from it – which is food.
Not all rice plants, though, are the same in physical characteristics and attributes. Their needs in order to grow properly may not also be the same. This is because this plant has many varieties that in order to make them grow well, their specific needs, conditions for growing, and other factors must be considered, provided or eliminated.
Although some rice plants are not the same in many ways, they are alike in their basic parts. Proper understanding of the parts of this plant will help very much in understanding the development process to make this plant grow well and fully develop.
To know well these different parts, it is important to understand how they develop and function.
NEEDS OF RICE PLANT
Understanding the needs of the rice plant will help in guiding the growers in their activities to create an ideal environment for the excellent growth and development of the rice plants. Inadequate supply of the needs of rice plants make the difference between a good or poor harvest.
It must be understood, however, that some of the needs of the rice plants for their growth and development cannot be supplied by the growers as they are provided only by nature.
But except for those that cannot be controlled by farmers, most of the needs of the rice plants are readily available or can either be produced or managed by farmers.
To know well these different parts, it is important to understand how they develop and function.
Among the most important needs of the rice plants are the following: Soil, Water, Nutrients, Light, and Air
For farmers, the soil is a natural medium for all land plants that include the rice plant.
It differs, however, in classification, characteristics, physical and chemical compositions, and many other characteristics.
As an ideal medium for the good growth and development of rice plants, the soil should contain all the elements needed for the growth and development of this plant.
The absence, however, of the elements needed may be supplied by farmers.
Water is a raw material needed by the rice plant for manufacturing its food. Without it, the plant cannot manufacture its food.
Water carries carbohydrates, which is the compound needed for food manufacturing, and mineral nutrients to the different parts of the plant. These carbohydrates and minerals are essential for the life of the rice plant.
In most of the various stages of the development of the rice plant, water is very much needed. In terms of volume, however, the water needed by the rice plant differs.
During the seedling stage, the water needed by the rice plant is lower in quantity.
In the rice field, the rice plants during their early stage of growth and development (vegetative stage) need only shallow depth of water in order to facilitate tiller production and to promote firmer anchorage of the roots in the soil. During their reproductive stage, the rice plants need larger amount of water most especially during panicle initiation up to the flowering stage.
During the ripening stage, which is from milk, dough, yellowish and full ripening of grains, only a little amount of water is needed by the rice plants. No standing water is needed after the grains have become yellowish in color.
Normally, no more water is needed when the ripened grains of the rice plants are about to be harvested. The draining of the farm land is usually done ten days before harvesting the grains.
Nutrient deficiency may stunt the growth of rice plants. Too much of any of the nutrients can also affect proper growth and development.
There is direct relationship between the nutrients provided to the rice plants and their attainable yield.
The nutrients required by the rice plants can be divided into two groups. They are the major elements, which are needed in large amount, and the minor or trace elements, which are required in small amounts.
Most of these elements are obtained by the rice plants from the soil, water or air. But they may not be sufficient in amount. In order to supply the nutrients needed by the rice plants, fertilizers are applied in the soil.
Fertilizers are organic or inorganic. The organic fertilizers are from decayed matters while the inorganic fertilizers are those that are produced in factories.
Inorganic fertilizers are also called chemical fertilizers. Most of these chemical fertilizers come in granule form which are broadcast on the soil and some are in liquid form which is applied to the leaves of the rice plants by spraying it. The liquid fertilizer is commonly called foliar fertilizer.
The abundance or deficiency in certain elements needed by the rice plants may be determined through soil analysis. This can be done in specialized laboratories where soil samples are brought. After the analysis, soil experts can identify which nutrients are available or not in the soil.
Light is important during the panicle differentiation stage which is about three weeks before and three weeks after heading. Absence of light during this stage of the plant’s life-cycle will greatly affect yield.
The sun is the main source of light energy needed by the rice plants. During the dry season, when there is abundant sunlight, the rice plants give more yield compared during the rainy season. This is because the rice plants receive greater solar radiation during the dry season.
During the rainy season, the rice plants grow taller and have more leaves. This condition makes the rice plants shade each other and thus they do not get enough light energy thus producing less grains.
Gentle wind is helpful in dispersing the rice plant’s pollen. It also replenishes carbon dioxide supply needed by the plant for grain yield. But when it blows strongly, it can damage the rice plant especially after the heading stage. It can also cause lodging of the plants and inflict damage to their leaves.
Strong winds also enhance the spread of diseases like bacterial blight and those caused by fungi.
CARE OF RICE PLANT
Taking care of the rice plant is an important aspect of work in rice growing. Without proper care, the rice plant may not give the maximum yield expected by the growers.
Thus, rice growers should always observe the plant to determine its needs. It is not a good practice in rice
growing to visit and observe the plant only once in long intervals which is commonly done by most farmers.
Among the important tasks that should be undertaken in providing care to the rice plant are the following: Application of fertilizer, Weed control, Insect control, Disease control
Fertilizers play an important role in the manufacture of food, reproduction, maintenance, and growth of the rice plant. Thus, application of the correct fertilizer in the correct amount helps greatly in the proper growth and development of the rice plant.
Weeds compete with rice plants for nutrients, water, space, and light. They also harbor pests and diseases, increase cost of production, and lower the quality of the crop.
Uncontrolled weeds can reduce the potential yield of the rice plant. Losses in yield can reach up to 60% in rice production in upland crops, 34% in transplanted plant, and 45% in direct-seeded, lowland rice plant.
There will always be a threat of insect pest infestation on the rice plant. This is because insects, which are best adapted to warm and humid environment, continue reproducing throughout the year.
Diseases in rice plants affect both the quantity and quality of the grains produced by the rice plant.
The diseases that affect rice plants are mainly caused by living organisms. These organisms are classified into four groups; fungi, bacteria, viruses and nematodes.
Planting rice can be done in different ways. Examples of methods for planting them are by transplanting the seedling, broadcasting the pre-germinated seeds, or by drilling the seeds in the holes or furrows.
Another practice being popularized in the country is by way of mechanical rice planter. There is still another one and it is called “parachute planting”.
Among these methods of planting rice, the most popular is rice transplanting. Next in popularity is the broadcasting of the pre-germinated seeds which is called “Sabog-Tanim”.
The drilling of the seeds in the holes is commonly done in hilly areas where land cultivation is difficult.
These practices of rice planting are presented in some details for better understanding.
The rice plants do not bear fruits or grains at the same time though. This is because rice varieties have different number of days to reach maturity. Among the rice varieties now being used for planting by farmers are varieties that reach 102 days while others have up to 135 days from the time of planting up to harvesting.
The best way to determine when the grains are to be harvested is when about 80 to 85 percent of the grains in the panicle are ripe. If the grains are harvested too early, they become powdery when milled and therefore not good for eating. On the other hand, if they become over-riped, they will easily fall off from the panicles and unto the ground. Over-riped grains when milled result in broken rice grains which are not preferred by the consumers.
The more scientific way of determining whether the grains are ready to be harvested is through the use of a moisture meter which measures the moisture content of the grains. The rice grains are ready for harvesting if the moisture content is between 20 to 24 percent. However, the moisture meter is only useful during the dry season.
Normally, the harvesting of the grains is performed manually with the use of a sickle. The stalks which hold the panicles are cut at the right length. Since the common way of threshing is performed with the use of mechanical rice threshers, the stalks that bear the panicle are cut shorter than when threshing is done through other means.