The botanical name of Tapioca is Manihot esculenta Crantz.; it belongs to family Euphorbiaceae
Varieties: CO 2, CO 3, CO (TP) 4, MVD 1, H 165, H 226, Sree Vishakam (H.1687), Sree
Sahaya (H.2304), Sree Prakash (S. 856), Sree Vijaya, Sree Jaya, Sree Rekha and Sree Prabha.
Soil: Any well drained soil preferably red lateritic loam with a pH range of 5.5-7.0. Thrives best in tropical, warm humid climate with well distributed rainfall of over 100 cm per annum. Cultivated
upto an elevation of 1000 m.
Season and planting: Plant throughout the year under irrigation. Plant during April for rainfed crop. Select healthy mosaic free vigorous plants for taking planting materials. Prepare setts of 15 cm long with 8 – 10 nodes from the middle portion of the stem. Avoid mechanical damage
while preparation and handling of setts. The cut end should be uniform. Dip the setts in Carbendazim 1 g in one lit of water for 15 minutes before planting. Plant the setts vertically with buds pointing upward on the sides of ridges and furrows. 17,000 setts are needed for one ha.
For rainfed conditions, treat the setts with a mixture of Potassium chloride @ 5 g/lit and micronutrients viz., ZnSO4 and FeSO4
each @ 0.5%for 20 minutes.
Dip the setts for 20 minutes in Azospirillum and phosphobacteria each at 30 g/lit.
Preparation of field: Plough the field 4 – 5 times to get a fine tilth. The soil depth should be atleast 30 cm. Form ridges and furrows at the following spacings:
Irrigated: 75 x 75 cm (17,777 setts) and 90 x 90 cm (12,345 setts)
Rainfed: 60 x 60 cm (27,777 setts)
Under Kanyakumari conditions: 90 x 90 cm (12,345 setts)
Irrigation: First irrigation is given at the time of planting. Life irrigation is given on the 3rd day followed by once in 7 – 10 days upto 3rd month and once in 20 – 30 days upto 8th month.
Sequential cropping: Raise CO 2 vegetable cowpea during March and harvest green pods before planting cassava during June –July. After green pod harvest, incorporate the cowpea haulms into the field by disc ploughing. Through sequential cropping 50% reduction in application of FYM (12.5 t/ha) and P (30 kg/ha) is ensured.
Manuring
Irrigated crops: Apply 25 t FYM/ha and incorporate at the time of planting. Apply 45:90:120 kg NPK/ha as basal and 45:120 kg NK/ha 90 days after planting during earthing up.
Rainfed crop: FYM at 12.5 t/ha along with 50 kg N, 65 kg P and 125 kg K/ha as basal. 2 kg of Azatobactor as soil application at 30 – 60 days after planting on receipt of showers (2.0 kg Azatobacter + 20 kg FYM + 20 kg soil per hectare).
Chlorosis: Foliar spray of 1% FeSO4 + 0.5% ZnSO4 at 60 and 90 DAP.
After cultivation: Fill up the gaps within 20 days of planting. Carry out 1st weeding 20 days after planting. Subsequent weedings should be done once in a month upto 5 months depending upon the weed intensity
Thin to two shoots per plant during 60th day. Grow aggregatum onion, coriander, short duration pulses and short duration vegetables as intercrops.
Plant protection protection Against Pests
Mites: Soaking spray with dicofol 18.5 EC 2.5 ml/lit during 3rd and 5th month.
White fly (Bemisia tabaci)
Integrated pest management practices:
1. Remove alternate weed hosts viz., Abutilon indicum.
2. Install yellow sticky trap at 12 Nos/ha.
3. Use nitrogen judiciously.
4. Avoid excessive irrigation.
5. Spray neem oil 3 % or fish oil rosin soap 25 g/lit or methyl demeton 25 EC 2 ml/lit. While using neem oil teepol or sandovit should be added at 1 ml/lit for better contact with foliage. Apply methyl demeton in the early stage and phosalone in the late stages of crop growth.
6. Avoid use of synthetic pyrethroids.
7. Avoid extending the crop growth beyond its duration.
Spiralling whitefly
1. Grow resistant genotypes.
2. Install sticky cum light trap and operate between 4 to 6 AM to attract the adult.
3. Spray dichlorvos 76 WSC @ 1 ml/lit or triazophos 40 EC 2 ml/lit. Add wetting agent.
4. Conserve parasitoids Encarsia haitiensis, E. guadeloupae.
Protection against Diseases
Mosaic: Select the planting materials from healthy plants. For the control of white fly vectors, adopt IPM practices mentioned above.
Cercospora Leaf spot: Spray Mancozeb at 2 g/lit twice at 15 days interval.
Tuber rot: Avoid water stagnation. Give good drainage facilities. Spot drenching with Copper oxychloride 2.5 g/lit.
Iron deficiency: Spray 3 to 4 times Ferrous sulphate 2.5 g/lit on the appearance of deficiency symptom at weekly intervals. Equal quantity of lime should be added for neutralising the solution.
Crop duration: 9 to 11 months.
Yield
Irrigated : 40 - 50 t/ha
Rainfed : 20 - 25 t/ha
