Tillage and residue retention effect on crop and water productivity of Indian mustard (Brassica juncea) under rainfed conditions

A field experiment was conducted during rabi season of 2014-15 and 2015-16 to study the effect of moisture conservation techniques and tillage management practices on growth, productivity and economics of Indian mustard [Brassica juncea (L.) Czernj and Coss.]. The experiment was laid out in split-plot design with three replications in cropping system mode. The main plot treatments consisted of four moisture conservation practices adopted inkharif season cropviz. ridges and furrows (RF), RF + crop residue (CR) 4 tonnes/ha, RF + CR 2 tonnes/ha + vesicular arbuscular mycorrhiza (VAM) and flat sowing (FS) and in sub plots; five zero tillage management techniques, viz. zero tillage (ZT), ZT + seed priming, ZT + CR 4 tonnes/ha, ZT + CR 2 tonnes/ha + Hydrogel and conventional tillage (CT) were executed in mustard. Results revealed that moisture conservation technique, RF + CR 4 tonnes/ha in main plot and tillage management practice ZT + CR 4 tonnes/ha in sub plot recorded significantly superior growth parameters, physiological indices, yield attributes and yield values over rest of the treatments. Sowing in furrows under RF + CR 4 tonnes/ha recorded highest values for seeds/siliqua and siliqua length to the tune of 13.16 and 4.17 cm, seed yield (2.12 tonnes/ha) and stover yield (7.46 tonnes/ha), respectively. Furthermore under RF + CR 4 tonnes/ha treatment registered significantly higherWUE (21.63 kg/ha/mm) as well as maximumN, P and K uptake values of 102.7, 21.02 and 97.15 kg/ha, respectively. Highest net returns of '54100/ha as well as B: C ratio (2.88) were obtained under RF + CR 4 tonnes/ha. In sub-plots, ZT + CR 4 tonnes/ha gave significantly higher values of siliquae/plant, seeds/siliqua and siliqua length to the tune of 342, 13.18 and 4.05 cm, respectively. ZT + CR 4 tonnes/ha recorded maximum seed yield (2.05 tonnes/ha) closely followed by ZT + CR 2 tonnes/ha + Hydrogel (1.94 tonnes/ha) and both the treatments were statistically at par. Water use efficiency under ZT sowing with CR 4 tonnes/ha and ZT + CR 2 tonnes/ha + Hydrogel, gave statistically at par values of 20.93 and 19.72 kg/ha/mm, respectively. In spite of higher cost of cultivation, significantly maximum net returns ((sic)49500/ha) were obtained under ZT + CR 4 tonnes/ha. Thus on the basis research findings, it can be established that under rainfed conditions after kharif crop harvest planting of Indian mustard can be done in left over furrows without any tillage with application of ex-situ CR 4 tonnes/ha or with CR 2 tonnes/ha + Hydrogel to save time, reduce cost and capitalize of residual moisture.