Mulch and compost effects on yield and corm rots of taro

Abstract

The potential of reducing losses due to corm rots on taro ( Colocasia esculenta cv. Bun-long) using organic farming practices was evaluated in an Andisol under rain-fed conditions during successive seasons between 1996 and 1998. Treatments were: (1) inorganic fertilizer plus pre-emergent herbicide (control); (2) control with additional calcium (Ca) and alfalfa pellets; (3) chicken manure with silage mulch; (4) chicken manure with wood chip mulch; (5) chicken manure with macadamia nut compost and silage mulch; and (6) solarization plus chicken manure and silage mulch. Taro corms were harvested at 7, 9, and 11 months after planting (MAP). There were no significant effects of compost, Ca+alfalfa pellets, or solarization on taro yield. Plots that included mulch produced significantly greater fresh weight corm yields and higher percentage corm dry matter, but also showed a higher incidence of corm rots compared to non-mulched plots. Mulching appeared to increase soil moisture content which promoted both growth of taro and conditions conducive to corm rot. Although yields were increased in treatments with mulch, these increases in crop value were not sufficient to cover increased costs of production.