What is Zero Tillage• Placement of seed in to soil without soilpreparation• It is an extreme form of minimumtillage. Primary tillage is completely avoided& secondary tillage is restricted to seedbedpreparation in the row zone only• it is the direct sowing of seed in the fieldwithout any disturbance to the soil e.g.sowing of wheat in standing cotton.
Some confusing terms• Reduced tillage: Tillage operation is reduced to actualnumber of tillage required for that crop.• Minimum tillage: Minimum tillage is aimed atreducing tillage to the minimum necessary forensuring a good seedbed, rapid germination, asatisfactory stand and favorable growing conditions.• Double zero tillage: If both consecutive crops aresown by using zero tillage practices ,then this practiceis called double zero tillage. e. g. if wheat and cottonare sown by ZT
Importance of zero tillage• Water shortage is a major constraint to sustainingand increasing the productivity of both cotton &rice-wheat cropping systems.• In recent years , drought has become a limiting factorin crop production , and farmers have come to realizethe full effects of soil erosion. It has been shownthrough research and farmer experience thatexcessive tillage removes surface residues whichprotect the soil. Also, in the dry years during the 80’s,the importance of saving soil moisture wasemphasized.
• As late sowing of wheat is a major problem ofboth rice and cotton cropping system and is amajor constraint in getting high yield. Byadopting zero or minimum tillage, we can sowwheat crop at proper time and not to wastetime in seed bed preparation.
In Pakistan this system consumes around 1.7million hectares. Punjab covers 70 per cent of thetotal rice area of the country. Around 80 per centof it is covered by fine Basmati varieties whichmature in November.Farmers remain busy in harvesting, thrashing andhandling of rice straw until early December. Thisalong with land preparation delays wheat sowing.The best time to plant wheat after rice is fromNovember 1-21. Thereafter, delay of one dayresults in yield reduction by 30-35kg per hectare.
• Zero-tillage planting is a resource-conserving approach (Erenstein et al.2007)• Helps to control obnoxious weeds ( Erenstein and Laxmi 2008)• Less fuel consumption, shortened ﬁeld time during tillage operations(Juergens et al., 2004)• Better soil structure, texture and aggregate stability (Ghuman and Sur,2001)• Protective effect of crop residues left over the soil (Dabney et al., 2004).• Increased soil water availability and increased number of Biopores, thatmay facilitate root growth (Martino and Shaykewich, 1994).
• Increase in soil density.• Reduced infiltration rate and pore space.• The seedling establishment in zero tillage is 20% less than inconventional methods.• Require 20-30% more seed and fertilizer
Contradiction• zero tillage is simply placing the seed on soil surfaceand no tillage operation is carried out for instancesurface seeding of wheat in standing cotton in relaycropping system.• All crop may not be sown through surface seeding sozero tillage may be defined as sowing of crop with notmore than two number of tillage via zero tillagemachines like happy seeder.
• A common perception by farmers is that zero tillingdoesnt work, that crop yields will be lower, and thatcrop quality is poorer. Some• People think a zero tilled field is less aestheticallypleasing since the field is left alone with plant andweed residues over its surface, indicating thepotential for increased pesticide or herbicide costs.However, these perceptions may be false. It takesapproximately 5 years before a real benefit can beobserved and demonstrated, and most• People tend to ignore benefits that aren‘t readily seen
References• Erenstein, O., and V. Laxmi. 2008. Zero tillage impacts in indias rice-wheat systems: A review. Soil and TillageResearch 100 (1−2): 1−14• Erenstein, O. 2007. Resource conserving technologies in rice-wheat systems: Issues and challenges. In Science,technology, and trade for peace and prosperity: Proceedings of the 26th International Rice ResearchConference, October 9–12, 2006, New Delhi, India, ed. P. K. Aggarwal, J. K. Ladha, R. K. Singh, C.Devakumar, and B. Hardy. Los Baños, Philippines, and New Delhi, India: International Rice ResearchInstitute, Indian Council of Agricultural Research, and Nationa Academy of Agricultural Science.• Ghuman, B.S., Sur, H.S., 2001. Tillage and residue management effects on soil properties and yields on rainfedmaize and wheat in a subhumid subtropical climate. Soil Till. Res. 58, 1–10.• Juergens, L.A., Young, D.L., Schillinger, W.F., Hinman, H.R., 2004. Economics of alternative no-till springcrop rotations in Washington’s wheat–fallow region. Agron. J. 96, 154–158• Dabney, S.M., Wilson, G.V., McGregor, K.C., Foster, G.R., 2004.History, residue, and tillage effects on erosionof loessial soil.Trans. ASAE 47, 767–775• Martino, D.L., Shaykewich, C.F., 1994. Root penetration proﬁles of wheat and barley as affected by soilpenetration resistance in ﬁeld conditions. Can. J. Soil Sci. 74, 193–200.