Mulching-Induced Alteration of Microclimatic Parameters on the Morpho-Physiological Attributes in Onion (Allium cepa L.)

Abstract

The effects of mulches (rice husk, sawdust, ash and burnt soil) on soil temperature, moisture conservation of soil and to relate them with morpho-physiological attributes of onion were studied. All mulches except ash were effective in conserving soil moisture. Sawdust mulch retained soil moisture most effectively followed by rice husk and burnt soil. Almost at all stages of growth and at any time of the day, ash mulch retained the soil temperature most effectively and least effectively by sawdust. Dry matter accumulation, leaf area index (LAI), plant height and root lengths were significantly influenced by these mulches. Mulching caused a higher number of scapes but the effect on number of scapes, their fresh and dry weights were insignificant. Ash mulch induced early flowering while the other mulches significantly delayed it. Thus, the use of ash as mulch was better compared to the other three mulches. This might be due to the increased soil temperature under the ash mulch. Further work is required to elucidate the fertilising effect of the mulches.