Bamboo and Rattan/Rattan/Course-1 Unit-5
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- 1 Seed Collection, handling, processing and storage
- 2 Assignment
- 3 Assignment
- 4 Assignment
- 5 Assignment
Seed Collection, handling, processing and storage
Rattan is extensively used in the manufacture of a wide range of furniture and handicraft items for low, medium and high-end markets. Most of the raw material of the local industry is obtained by harvesting the wild rattan resources from the natural forests. As cane furniture became more popular and enterprenuership in cane products started proliferating more and more demand for raw materials arose. These demand for raw cane was also increased from the international market. These demands coming from both domestic as well as international markets resulted in the need to harvest more cane from the natural forests. This led to cutting of so much cane from the forests that the growth of cane did not keep pace with the harvest amount. This led to over-exploitation of canes. Coupled with greater demand for cane from the forests there was destruction of the natural forests due to changing land use. This has resulted in some useful rattans becoming scarce or even being reduced to very low population levels in many areas.
At present the naturally available quantity of canes is not sufficient to meet the increasing demands. There is a wide gap between demand and supply and this can be minimized only by augmenting the existing resources by large scale cultivation in the natural habitat. Large scale cultivation requires detailed knowledge of methods of seed collection, propagation and making nursery as also planting practices. Plants can be easily raised from seeds but when seeds are not available in sufficient quantities, other methods such as use of suckers and rhizomes or tissue culture techniques can be used for seedling production. The cost of production is cheaper when plants are raised from seeds as compared to use of suckers, rhizomes etc.
Check Your Progress Exercise 1
5.2 Flowering and fruiting
Flowering of rattans generally occur annually. The flowering time varies with the species, and with geographical location (Unit 3). In general, mature fruits can be collected for most of the species during March to June.
5.3 Handling of Seeds
5.3.1 Seed collection
Fruits of nearly all rattans contain only one seed. Only ripe fruits should be collected since only seeds from ripe fruits would give good germination percentage. The ripeness is checked by pressing the fruits in between the fingers. If the scaly cover gets detached easily then the fruits are ripe enough for collection. The outer scaly cover of the fruits and the fleshy inner part should be removed to increase the germination percentage of the seeds. This is carried out in two stages. First the scaly cover is removed by crushing the fruits with hands or under foot after mixing with sand. The seeds are then soaked in water for about 48 hours to induce fermentation. This makes it easy to remove the fleshy part of the seed by rubbing with hands. Cleaned seeds can be stored for a week under moist conditions. Seeds should not be dried since dry seeds fail to germinate.
Figure 5.1: VS and CS cross-section of fruit showing all the layers
5.3.2 Seed storage
Seeds germinate best when sown soon after extraction and cleaning. However, when large batches of fruits are harvested a longer period of storage is sometimes necessary. Care should be taken that the seeds are not allowed to dry during storage. Often the fruits or the seeds are stored in plastic bags. The term ‘viability’ is used to describe the ability of the seeds to germinate and form seedlings, and later plants. In rattan, if more than 50 per cent of the seeds produce healthy seedlings the seed lot is said to be viable. The moisture content during storage is very critical - the moisture content of naked seeds must be kept between 45% and 55% during the storage period. This is because a seed moisture content of more than 60% will induce seed germination during storage itself and if it is less than 40% it will decrease the seed viability.
The seed viability under various storage conditions is given in the following table:
.Need to put a table here
Check Your Progress Exercise 2
5.4 Raising of seedlings
5.4.1 Establishment of Nursery Beds
Sowing of seeds directly in soil cannot be done for Rattans – the germination percentage of seeds so-sown is very low. For good germination of seeds the soil needs to be porous - this enables the young roots to grow easily. Also though the soil has to be moist it should not be water-logged. Such conditions can be met by preparation of raised nursery beds. A bed should be prepared by arranging a 10 cm thick layer of sandy loam on the flat ground. This sandy layer should be overlain with a 3 cm thick layer of saw dust. To prevent the saw dust and sand from being washed away when the bed is watered we need to provide support from the sides. This is carried out by supporting the bed from all sides with wooden planks, bricks or split bamboo. The standard size of the bed is 12 m x 1.2m. The increase in width of the nursery bed can result in overcrowding, over shading, more rapid spread of pest diseases, and interference in carrying out routine weeding, fertilizing and watering.
The site chosen for the seed bed should be flat and should be near a reliable water source. Since the seedlings grown in the seed-beds have later to be transferred into polythene bags, having the nursery beds adjacent to the polythene bag nursery would facilitate transplanting work later.
Since rattan is usually grown in areas that have heavy rain a shelter is built over the seed bed to protect the seeds and young seedlings from heavy rain and direct sunlight. Heavy rains churn up the seed bed and expose the seeds. This can create a lot of extra work when thousands of seeds/seedlings are handled. Locally available materials such as palm fronds, grass etc are used for building a shelter. In case of permanent nurseries, the use of agro-nets is advisable.
Figure 5.2: Picture of a shelter
5.4.2 Seed sowing and after care
The processed seeds should be carefully spread over the seed bed and covered with 2 cm thick layer of sawdust. All the seeds should be covered completely. Daily watering is needed to keep the bed moist. Only a fine spray of water is used while irrigating the seeds to avoid churning up the beds. Any exposed seeds should be covered up immediately.
Many plants other than rattan seedlings may also grow – these are called weeds. Periodic removal of weeds from the seed beds – called weeding – has to be carried out.
Check Your Progress Exercise 3
At the right time seedlings have to be removed from the nursery beds and placed in soil contained in polybags – this process is called transplantation. As rattan seeds germinate, the first sign is the emergence of a spear like protuberance from which the seedling leaves expand later. Seedlings are generally ready for transplanting when the first seedling leaves are fully expanded.
Figure 5.3: Seedlings ready for transplantation.
Before transplantation, the nursery beds should be thoroughly watered to loosen the sowing medium so that seedlings can be picked out easily with minimum damage to the root system. A hole - deep enough to accommodate the seedling roots - is made in the soil medium of the polybag to which the seedling is to be transplanted.
Figure 5.4: Side-view of a pot showing the depth of the hole into which the seedling is planted
For carrying out the transplantation the seedling is held between the fingers with its roots suspended into the hole. The hole is then filled with soil before the seedling is released so that the roots are not compressed and crumpled. Seedlings are watered thoroughly immediately after transplantation. Within a week or so, a survey of the nursery should be carried out to know any casualties. Plants that did not survive the transplantation shock – dead plants – should be replaced with fresh transplants, as soon as possible, so that the polybag nursery space is not left vacant.
5.5.2 Maintenance of seedlings in polybags
The aftercare of seedlings in poly bags consists of
- Continual replacement of weak or dead seedlings: Any dead or weak seedling should be replaced as soon as possible to ensure uniformity in size of living seedlings.
- Regular watering: Depending on weather conditions, watering should be carried out as often as necessary to keep the soil medium moist. On a hot day it may be necessary to water the plants twice.
- Weeding: Weeding and breaking the soil crust can be done together and should be carried out before application of fertilizer.
- Fertilization: About two weeks after transplanting, fertilizer application is started with 8-10 granules of compound fertilizer (NPK) per seedling. Thereafter, fertilization can be carried out once a month and the amount can be gradually increased. Two months after transplanting, a mixture of cow dung and groundnut cake with water may be poured in the polybags which will increase the
- Pest & disease control: There is a need to ensure that the plants are kept free of pests and diseases. A detailed description is given in the block/unit on diseases.
Check Your Progress Exercise 4