Micropropagation

Use of Tissue Culture in Sugarcane Agriculture
Tissue Culture technology is useful in developing plantlets of any plant in the laboratory from any young part of the plant. Using apical meristem culture technique faster multiplication of a sugarcane variety can be done. Apical meristem (growing part of sugarcane) is dissected and inoculated on a growth medium having definite nutrient composition. The apical meristem starts producing tillers in the laboratory after about 45 days of incubation in temperature and light controlled conditions. The procedure of separation of tillers, inoculation in a suitable medium and incubation under suitable conditions is repeated so that from one apical meristem one can develop millions of plantlets in a period of seven to eight months. The plantlets thus produced are absolutely disease free and true to their original variety from which apical meristem is obtained. The plantlets developed in the laboratory are hardened in temperature and humidity controlled green houses. The well hardened plantlets thus developed are useful in planting Breeders seed nursery in three tier system of seed multiplication. A seed multiplication ratio of 1:25 to 30 (planting material for 25-30 hectares is obtained from one hectare seed nursery) is obtained from the seed nursery planted with tissue culture plantlets. Conventionally a seed multiplication ratio of 1:15 (and in conventional Breeders seed nursery 1:5 or 1:7) is obtained with two eye bud sets. The well hardened plantlets developed when used give 98 to 100 % survival under field condition.

Salient Features of Sugarcane Micropropagation Plantlets

1. The plantlets are genetically pure, true to type, disease free and quality seed material.
2. The 98 to 100 % survival of well hardened plantlets under field condition.
3. Quicker and synchronous tillering and uniform growth
4. Higher seed germination and seed multiplication rate under field condition.
5. One hectare seed plot with 13500 tissue culture plantlets / breeder seed material for planting 25-30 hectares area using two eye-budded setts after 10 months of crop age.
6. Quicker and more than 95% germination of the seed material obtained from tissue cultured plantlets.
7. Quality seed material derived from three tier seed program resulted increase in sugarcane yields to the tune of 28-30 tons per hectare in commercial cane.

Three tier seed multiplication using tissue cultured sugarcane plantlets

Three tier seed production technology is the vital component of quality seed cane production.
1. Breeder seed
Sugarcane tissue cultured plantlets are recommended as breeder seed.
2. Foundation seed
Tissue cultured plantlets are recommended to grow foundation seed plot. It is very essential to follow the recommended package of practice to grow seed nurseries. A seed multiplication ratio 1:30 (planting material for 30 hectares is obtained from one hectare tissue culture planted seed nursery) is obtained from the seed nursery planted with tissue culture plantlets. Conventionally a seed multiplication ratio of 1:15 is obtained with two eye budded setts.
3. Certified seed
Ten month old canes obtained from the foundation seed plots are recommended as seed to plant certified seed plots. Single or two eye bud setts with planting distance between two sett should be one feet. From the one hector certified seed will sufficient to plant 15 ha commercial sugarcane field (Ratio 1:15).

Single eye bud settling production:
Seed material raised through tissue culture can be utilized for production of single eye bud settlings plantlets which will resulted in production of quality planting material. There is 98 to 100% germination of eye bud if tissue cultured seed cane used for single eye bud plantlets.

Transplanting of Plantlets in field

The following methodology was developed for getting quality planting material from micropropagated sugarcane plantlets

• The plantlets well established and hardened in plastic bags are supplied in cardboard boxes. Each box contains 100 plantlets.
• These plantlets are treated with Vasant Urja for induced abiotic and biotic stress tolerance and improved growth.
• A well drained field should be selected and prepared as usual for raising seed nursery. Furrows should beopened at four feet distance. The recommended doses of manures and basal dose of fertilizers need tobe applied while preparing the field. The applied fertilizers should be well mixed in the soil.
• It is advisable to plant the plantlets in the field next day of supply. This helps in increasing survival underfield condition. If next day planting is not possible due to unavoidable circumstances, then removeplantlets from the boxes and keep them in bright sunlight and water them profusely once in a day.
• It is necessary to withhold watering the plantlets a day before planting in the field so that the soil in the plastic bag becomes hard and compact. This prevents damaging the root system during the removal of plastic bag. The damaged root system increases mortality in the field.
• Under more saturated atmosphere it is necessary to withhold watering of the plantlets for more than two to three days so that the soil in the plastic bag becomes hard and compact
• Keep the plastic bags containing plantlets in the field on ridges.
• Dig the pits of the size of the plastic bag at two feet distance in the center of the furrow.
• Remove the plastic bag carefully by taking a vertical cut with a sharp blade without disturbing the soil ball.
• The other field operations and subsequent care should be taken as per the recommended practice for the conventional seed nursery.
• Apply 15 Kgs. (4%) of granular Cartap hydrochloride or 25 kg Phipronil per hectare in the soil after fifteen days of transplantation and irrigate the field. This helps in preventing early shoot borer infestation.
• While applying the subsequent doses of fertilizers care should be taken not to injure the transplanted plantlets. The soil should be dug along the furrow away from the base of the plantlets with the help of pickaxe, fertilizer applied and subsequently covered with soil and irrigation is given immediately. Spot application of fertilizers or ring method of application of fertilizers need strictly be avoided.
• If necessary main shoot may be removed 35-40 days after transplanting.
• The major earthing up needs to be done at 90-100 days after transplanting.
• The major earthing up needs to be done at 90-100 days after transplanting

Advantages of using planting material from tissue cultured plantlets

• The planting material obtained from tissue culture plantlets is genetically pure.
• The planting material is disease and pest free. Therefore there is no need of giving Hot Water Treatment or Moist Hot Air Treatment to the planting material for making seed disease free..
• Multiplication of a sugarcane variety is faster.
• 2 to 2 1/2 times more planting material can be obtained from an unit area as compared to the conventionally planted seed plot.
• Bud germination in the field is 98-100 %. All buds germinate within a period of ten days after planting.
• Increase in sugarcane productivity to the tune of 30-35% and that in sugar recovery to the tune of 15%.
• Helpful in implementing season and varietal planting and harvesting programme in the area of operation of a sugar factory.
• Seed material obtained from Tissue Cultured plantlets is highly suitable for raising single eye bud settlings due to quicker and higher germination ability.It saves time, seed and cost

Precautions for using seed material obtained from micro propagated sugarcane plantlets

• While planting Certified Seed Nursery with the help of planting material obtained from tissue cultured plantlets care should be taken to use only nine to ten month old canes.
• The seed cane should be cut in to two eye budded setts with the help of sharp cutting knife and these need to be planted at a distance of nine to twelve inches.
• Plating of Certified seed nursery from foundation seed nursery raised from tissue cultured plantlets sett treatment with vasant urja solution (5ml/liter) should be done for 30 minutes.
• Recommended doses of fertilizers need to be applied as per the schedule.
• There is profuse tillering in the foundation and Certified seed plot planted with tissue culture planting material,. It is necessary to perform small earthing up operation after one and half months of planting and major earthing up after three to three and half months of planting to restrict unwanted tillering and to obtain good quality planting material.