Effect of planting methods and varieties on performance of modified TNAU cassava harvester

Abstract
Cassava is one of the most important tropical tuber crops that ensure food and nutritional security in the developing countries. In India, cassava is cultivated mainly in the southern states viz., Tamil Nadu, Kerala and Andhra Pradesh. Harvesting is one of the major difficult and labour intensive operations in cassava cultivation. In India, cassava is mostly harvested manually by hand. This study was attempted to evaluate the performance of tractor operated Tamil Nadu Agricultural University (TNAU) cassava harvester with two industrial varieties (H-165 and Mulluvadi) and two commercial planting system (Mound and Ridge) using six treatments in a randomized complete block design (RCBD). Based on the field performance trial, the shank length and width of digging blade were modified and then their dimensions were optimized for better performance. Among the selected treatments, it was found that a minimum damage of 4.12% was observed for H-165 variety under manual harvesting and a maximum damage of 9.05% for Mulluvadi variety in mound planting system under mechanized harvesting was noticed. The tuber spread length was highly correlated with the per centage damage (%) of cassava tubers. Thus, the tuber spread length is an important agronomical parameter to be considered while selecting the variety for mechanization of cassava harvesting. This study also confirmed that the ridge planting system is highly suitable for operating mechanized harvester as compared to mound planting system.