V. RAVI1 and T. RAMANANDHAM2
1Crop Production Division, Central Tuber Crops Research Institute, Sreekariyam, Thiruvananthapuram - 695 017, India
1ANGR Agricultural University Agricultural Research Station, Peddapuram, Andhra Pradesh, India
RAVI, V. and T. RAMANANDHAM, 2004. Zero energy cool chamber technique to increase the shelf life of cassava (Manihot esculenta L.) stem stored for propagation. Bulg. J. Agric. Sci., 10: 699-707
Healthy, mature stems of about 1.2 - 1.5 m length of three cassava cultivars viz., Sree Prakash, Sree Jaya and H - 165 were stored under two treatments viz., horizontally under the tree shade (T1) and in zero energy cool chamber (ZECC) (T2) for five months under hot, dry weather conditions. Insecticide chlorpyrifos (a.i. 20%) was applied to stems to protect from termite (Odontotermus sp.) and soft scale (Aonidomytilus albus) infestation. Fungicide mancozeb (a.i.75%) was applied to stems to protect from any fungal infection. Stems of three cassava cultivars stored in ZECC retained adequate moisture and carbohydrate content and showed greater percentage of sprouting. Stems of three cassava cultivars stored in ZECC retained greater moisture content (60.7 - 66.1%), greater percentage of fresh stems (61.2 - 75.0%), had greater starch content (264.0 - 268.3 mg / gram dry stem), showed greater percentage of sprouting (74.0 - 76.9%). Plants from these stems showed lesser reduction in storage root yield (3.5- 4.2 t/ha) as compared to storage root yield obtained from plants planted from fresh stems. It is therefore recommended that cassava stems can be stored horizontally in zero energy cool chamber with appropriate plant protection measures for a period of five months under hot dry weather conditions. Zero energy cool chamber technique ensures greater quantity of planting material and storage root yield than stems stored horizontally under the tree shade (traditional method).