Agriculture
Crop Production::Sugarcrops::Sweet Sorghum
 

SWEET SORGHUM (Sorghum bicolor)

CROP IMPROVEMENT

1. Season and Varieties

Season Variety (irrigated) Districts
Kharif (June- July) SSV 84, CSV 19 SS (RSSV 9) All Districts except Nilgris
Rabi ( Sept-Oct.) SSV 84, RSSV 9 All Districts except Cuddalore, Thanjavur, Thiruvarur, Nagapattinam and Nilgris
Summer(Mar.- April) SSV 84, RSSV 9 All Districts except Nilgris

Note: sowing should be avoided during July – August and November – January

2.  Varietal Particulars

Particulars SSV84 RSSV9
Parentage Sel From IS 23568 RSSV X SPV 462
Duration (days) 120-125 115-120
Area (districts) National level National level
Seasons (Pattam) Kharif Kharif
Grain yield Kg/ha 1000- 1200 800-1000
Green cane yield (t/ha) 30-35 35-40
Plant height (cm) 190- 210 240- 270
Juice extractability (%) 25.4 26.2
Brix (%) 17-19 18-20
Total soluble solids (%) 11.6 13.6
Reducing sugars (%) 3.18 1.81
Sucrose (%) 9.6 11.4
Ethanol yield (Kl/ha) 800- 1000 1000 -1200
CCS (q / ha) 16.5 25.8
Sheath color NT NT
Node 9-10 11-14
Midrib Green Dull Green
Earhead shape Oval Oval
Compactness Semi- compact Semi-compact
Grain colour White Creamy
Special features Turtle grain Round

1. TREATMENT OF SEED

Step 1: Treat the seeds 24 hours prior to sowing with Captan or Thiram 2 gm/kg of seed or Metalaxyl 4 gm / kg of seed to control downy mildew.

Step 2: Treat the seeds required for one hectare with 3 packets (600gm) of Azospirillum using rice gruel as binder.

Note: Dissolve 0.5 gm of gum in 20 ml of water. Add 4 ml of Chlorpyriphos 20 EC or Phosalone 35 EC. To this add 1.0 kg of seed, pellet and shade dry to control shootfly and stemborer.

2. FARM LAND PREPARATION

Form ridges and furrows at a spacing of 45 cm apart

3. SOWING

  • Seed rate of 10 kg/ha
  • Adopt a spacing of 45 x 15 cm (population 1,48,000/ha)
  • Sow the seeds at a depth of 2 cm and cover with soil

Note: Use increased seed rate upto 12.5 kg per hectare and remove the shoot fly damaged seedlings at the time of thinning or raise nursery and transplant only healthy seedlings.

4. IMPORTANCE OF INM

Application of inorganic nutrients alone in the long run will lead to soil and environmental pollution. Hence integration organic and inorganic fertilizer will sustain the soil heath and improve the cane yield of the sweet sorghum crop.

5. IMPORTANCE OF BALANCED NUTRITION

Application of balanced fertilizer at recommended dose in the right stage of the crop will not only improve the productivity but also improve the soil fertility and reduce the environmental pollution.

6. EVALUATION OF FERTILIZER REQUIREMENT

Soil testing is suggested tool for evaluating the fertilizer requirement. It has to be done before the cropping season well in advance so as to ascertain the native fertility of the soil and to recommend the correct dose of fertilizer which will reduce the fertilizer cost.

7. RECOMMENDED INM

  • Apply 12.5 tons of FYM/ha at last ploughing.
  • Soil application of Azospirillum @ 10 packets (2.0 kg/ha) after mixing with 25 kg of FYM + 25 kg of soil may be carried out before sowing/planting.
  • 12.5 kg /ha of MN mixture mixed with enough sand to make a total quantity of 50 kg and applied over the furrows and on top 1/3 of the ridges.
  • Apply NPK fertilizers as per soil test recommendations. If soil test recommendation is not available adopt a blanket recommendation of 120 : 40: 40 kg of NPK/ha

8. STAGES OF APPLICATION OF FERTILIZERS

  • Apply azospirillum and MN mixtures as basal
  • Apply half dose of N and full dose of P 2O 5 and K 2O basally before sowing.
  • Apply the balance N in two splits of 25% each on 15th and 30th day of sowing. 

4. Weed Management

  • Apply the pre-emergence herbicide Atrazine 50 WP – 500 gm /ha on 3 days after sowing followed by one hand weeding on 40-45 days after sowing may be given.
  • If herbicides are not used, hand weed twice on 15-20 and 30-40 days after sowing.

5.  Water Management

  • Water requirement: 400-450 mm
Stages No. of irrigation Days of transplanting / sowing of crop
Direct sown
Light soil
Irrigate for germination 1 1st day
Establishment 2 4th ,   15th day
Vegetative phase 1 28th  day*
Flowering stage 3 40th ,  52nd & 64th day*
Maturity phase 2 75th , 88th   day
Heavy soils
Irrigate for germination 1 1st day
Establishment 2 4th &17th   day
Vegetative phase 1 30th  day
Flowering stage 3 40th ,  52nd & 75th day
Maturity phase 1 90th   day

*Critical stage for water requirement

6. Post harvest Management

Harvesting

  • Consider the average duration (100-110 days) of the crop and observe the crop.  When the crop attains physiological maturity the hilum region of the seed will become dark in colour and indicate the ideal stage of harvest.  
  • Cut the earheads and sundry the panicles to remove the excess moisture.
  • Cut the stem at ground level after the removal of leaves at the nodes.
  • Canes are made in to bundles of 10 to 15 canes each and transported to the mills for crushing.
  • The harvested cane should be covered with leaves (trashes) to avoid direct sun light.
  • The canes are to be transported to the mills within 48 hours of cutting.

Storage of seeds

Dry the seeds below 10 per cent and mix 100 kg of grains with 1 kg of activated kaolin to reduce the rice weevil and rice moth incidence

Spray•malathion 50 EC 10 ml/lit @ 3 lit of spray fluid/100M2 over the bags during storage in godowns.

Sweet Sorghum

ETHANOL FROM SWEET SORGHUM VARIETIES

• Potential yield -80 to 100 t/ha (US reports)

• Longer maturity yield surpasses 100 t/ha

• Ethanol yield –2639 lit/ha (Brazil)–7000 lit (China)–3000 lit (South Africa)–4790 lit (US)

• National variety of India SSV 84 -40 –50 t/ha bio mass ; 40% of Juice yield and 4500 lit/ha of ethanol (NRCS report)