Using organic wastes as compost and mulch for potato (Solanum tuberosum) in low water-retaining hill soils of north-west India

A field study was conducted during 1992-96 to evaluate the usefulness of Pamakani (Eupatorium adenophorum Sprengel) as compost and pine (Pinus roxburgii Sarg.)-needle as mulch in potato (Solanum tuberosum L.) all silty clay-loam, Typic Hapludalf having pH 5.6. The euopatorium compost contained 1.8% N, 0.05% P and 0.45% K compared with farmyard manure containing 1.62% N, 0.08% P and 0.32% K. The treatments included application of 20 tonnes/ha farmyard manure at planting of potato with no mulch and pine needle mulch @ 10 tonnes/ha and 2 levels of N (60 and 120 kg N/ha). Another treatment combination was application of 10 tonnes/ha eupatorium compost + 10 tonnes/ha farmyard manure and 2 levels of 60 and 120 kg N/ha. Potato tuber yield under treatment 10 tonnes/ha farmyard manure + 10 tonnes/ha eupatorium compost was similar to that recorded under both levels ofN + 20 tonnes/ ha farmyard manure, showing possibility of 50% substitution of farmyard manure with eupatorium compost. Pineneedle mulching maintained higher soil and plant water status, more roots and saved N equivalent to 60 kg/ha over no mulch treatment. The practice also saved 1 irrigation and gave about 50% higher yield of autumn and 22% higher tuber yield of spring crop.