000			05129nab a22004937a 4500
001			G95861
003			MX-TxCIM
005			20240528161505.0
008			210720s2012 ne |||p|op||| 00| 0 eng d
022	0		_a0378-4290
024	8		_ahttps://doi.org/10.1016/j.fcr.2011.11.026
040			_aMX-TxCIM
041			_aeng
090			_aCIS-6695
100	1		_aJohansen, C. _96569
245	1	0	_aConservation agriculture for small holder rainfed farming : _bopportunities and constraints of new mechanized seeding systems
260			_aAmsterdam (Netherlands) : _bElsevier, _c2012.
500			_aPeer review
500			_aPeer-review: Yes - Open Access: Yes|http://science.thomsonreuters.com/cgi-bin/jrnlst/jlresults.cgi?PC=MASTER&ISSN=0378-4290
520			_aSmall holder farmers in rainfed agriculture believe that soil tillage is needed to maximize crop yields. However, as cropping intensity, and hence tillage intensity, increases there may be a decline in particular physical, chemical and biological properties of the soil which limit crop yield. This is primarily caused by declining soil organic matter, its oxidation being accelerated by tillage, particularly in warmer climates, and exacerbated by the limited return of above-ground biomass to the soil due to its competing use for other purposes. In large-scale commercial agriculture declining soil quality has been effectively addressed by conservation agriculture—cropping systems based on minimum tillage, crop residue retention and appropriate crop rotations and associations, preferably including legumes. This has required development of minimum tillage planting equipment along with herbicide technology to achieve weed control that is traditionally achieved through tillage. However, a shortage of mechanized options suitable for small holder farmers is creating an impediment to the adoption of conservation agriculture practices that would arrest the decline in soil quality in their fields. In South Asia, two-wheel tractors are replacing animal-drawn ploughing in small holder plots. This speeds the tillage operation and hence the turnaround time between crops, which may increase opportunities for crop intensification, but the problems associated with full tillage remain. Over the previous decade planter attachments to two-wheel tractors have been developed which permit seed and fertilizer placement with minimum to zero tillage in a single-pass. Recent tests have demonstrated that use of these implements can produce crop yields equal to or better than conventional tillage involving hand broadcasting of seed and fertilizer. Further, fuel and labour costs, seed and fertilizer inputs and turnaround time between crops can be reduced. In Africa, the introduction of animal-drawn rippers and direct seeders, originally developed for small-scale farmers in Brazil, is considered as a major breakthrough to small-scale farmer mechanization. It significantly reduces labour required for planting and benefits may be even greater if herbicides can be effectively used for weed control. Nevertheless, movement towards minimum tillage with two-wheel tractor mounted planters and animal-drawn direct seeding equipment is constrained by weed management issues. There are problems of availability and of safe and effective use of herbicides by resource-poor farmers and there is a need to develop more integrated weed management strategies that can be combined with small-scale planters. There is also a need to optimize the performance of small-scale planters to suit farmers’ needs in different agro-ecological environments. Tools and concepts are now available to implement conservation agriculture for small holders and thereby increase profitability of their cropping practices and at the same time improve soil quality and sustainability of their livelihoods. However, much more adaptive research and on-farm evaluation is needed across a diverse range of soils, cropping systems and agro-ecological regions to bring conservation agriculture to more small holders.
536			_aConservation Agriculture Program
546			_aText in English
591			_aElsevier
594			_aINT2939
595			_aCSC
650		7	_aAnimal power _2AGROVOC _926454
650		7	_aDirect sowing _2AGROVOC _91792
650		7	_aCrop rotation _2AGROVOC _91807
650		7	_aMinimum tillage _2AGROVOC _98744
650		7	_aMulching _2AGROVOC _95840
650		7	_aSeed drills _2AGROVOC _930977
650		7	_aSoil organic matter _2AGROVOC _93022
650		7	_aStrip tillage _2AGROVOC _910798
650		7	_aTractors _2AGROVOC _95220
650		7	_aWeed control _2AGROVOC _91308
650		7	_aZero tillage _2AGROVOC _91753
700	1		_aHaque, M.E. _916878
700	1		_aBell, R.W. _96570
700	1		_aThierfelder, C. _gSustainable Intensification Program _gSustainable Agrifood Systems _8INT2939 _9877
700	1		_921487 _aEsdaile, R.J.
773	0		_tField Crops Research _gv. 132, p. 18-32 _dAmsterdam (Netherlands) : Elsevier, 2011. _wG444314 _x0378-4290
856	4		_uhttps://hdl.handle.net/20.500.12665/228 _yAccess only for CIMMYT Staff
942			_cJA _2ddc _n0
999			_c28804 _d28804