Vegetables

Most seeds normally remain viable for 2 or 3 years if stored under good conditions. To grow best vegetables either for home garden or for growing commercially try only certified seeds with, trueness to type and freedom from certain diseases. Good seeds are clean, viable, free from disease and true to the name variety. Therefore, buy only from seed firm of known integrity. High yielding, high price seeds should have 90% germination. Seeds of 50% germination is very poor.

Germination of Seeds

For germination of seeds adequate moisture, temperature and aeration are essential. The requirement of temperature for various vegetable seeds varies markedly. Some seeds do not germinate at low temperature while some others at high. Usually germination is optimum in between 40⁰ F and 60⁰ F. Seeds absorb moisture and swell and vital activities starts. Respiration begins and energy is supplied and this requires oxygen. Aeration is essential to supply oxygen. If supply of water is more or over wet aeration is poor and may hinder in germination.

Seed Treatments

Vegetable seeds are usually grown in nursery beds or in boxes. There are three types of seed treatments to control diseases.

1 Disinfestation

2 Disinfection.

3 Seed protection.

The first eliminates organisms present on the surface of seeds. Calcium hypochlorite, mercuric chloride and bromide water may be used. The second disinfectant eliminates organisms present within the seeds. For this hot water, formaldehyde and mercuric chloride are effective. In hot water treatment dry seeds are immersed in hot water 45 to 55⁰ C for 10 to 15 minutes. The third treatment protectants are fungicides to protect seeds from soil fungi. Nursery soil should be drenched before sowing of seeds. Commercial materials are also now available to treat seeds like Captan, Cerason, Thiram, Bavistin, Agrosan GN and antibiotics such as Agrimycin (0.01%), Streptocyline (0.01%) etc. To secure healthy seedling the seed treatments should be invariably done. If the outside nursery bed contain worms, maggot and such insects a combination of insecticides and fungicides should be applied like Aldrin, Dieldrin with Captan, Thiram etc. All chemicals should be handled carefully according to directions of the manufacturer.

If boxes are used for growing seedling the soil should be disinfected by heating the soil to 180 F for atleast one hour. If nursery beds are used the soil may be disinfected by 40% Formalin. One part formaldehyde (40%) mixed in 50 parts of water and saturates the soil. After 24 hours of treatments the seeds may be sown. If captan and formaldehyde is used, the nursery soil may be drenched about 10-12 days before seed sowing.

Preparation of nursery beds

The nursery beds should be prepared before the soil treatments. The nursery beds should be of one meter width and length four to five meter. The soil should be cultivated to a find tilth. All weeds, stones etc. should be removed. The beds should be raised to 15 to 20 cm. heights. If necessary, shade or shelter may be provided. Usually total bed area of 80-100 sq.m. is sufficient for most of transplanted seedlings to cover one hectare.

NPK nursery mixture may be applied along with compost on FYM during preparation of soil. After complete preparation and levelling the beds should he given soil treatment as mentioned above.

Sowing of seeds

The vegetable seeds should be sown in nursery beds in lines at 1.5-2 cm. below surface soiled at a distance of 5-6 cm. The distance from line to line should be 10-15 cm. After sowing cover the seeds with sieved compost very lightly. The beds should be watered with a sprinkler. The above distance from plant to plant or row to row may be changed according to size of seeds, kind of vegetables and type of seedlings. Similarly the depth of covering with compost varies with the kind of seed. Very fine seeds may be dusted over the nursery bed. Covering of other seeds may be one to two times their minimum diameter. During germination and after sprinkle water in the beds but no excessive. Over watering creates high humidity and poor aeration and contributes to "damping off" disease.

To transplant the vegetable seedlings to its permanent location the seedlings should be stocky, healthy and vigorous rather than spindly, weak and elongated plants. Moderate temperatures produce stocky growth. To harden some vegetable seedlings, seedlings may be transplanted one or two times to another nursery bed. In large scale condition watering may be withheld two to three days ahead of transplanting to permanent site.

The young seedlings in the nursery bed should protected against diseases and pests. Regular spray to young plants with Malathion 50 EC or Dithane M-45 or Sevin (0.2%) similar material at 10-15 days interval is necessary.

Most of the vegetable seedlings in the nursery bed is ready for transplanting when the seedlings are 4 to 6 weeks old. During uprooting every care should be taken not to damage roots. Light watering should be given at least 12 hours before lifting.

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(Horticulture)