Zero Energy Cool Chamber Technique to Increase the Shelf Life of Cassava (Manihot esculenta L.) Stem Stored for Propagation

摘要

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 (T_1) and in zero energy cool chamber (ZECC) (T_2) for fivemonths under hot, dry weather conditions. Insecticide chlor-pyrifos (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 protectfrom 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 periodof 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).