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Integration of chickpea and other rabicrops into rainfed rice-based systemsof the High Barind TractC. Johansen, A.M. Musa, D. Harris, M. Shafiqul Islam, and M. Omar AliThis paper examines some of the major constraints to developing rainfed ricerabicropping systems in the High Barind Tract (HBT) and suggests means ofalleviating them. Traditional rainfed rice cultivation in the HBT does not readilysynchronize with the subsequent cultivation of rainfed rabi crops primarilybecause of the creation of soil conditions unfavorable to the following cropsand the delayed sowing of rabi crops. For chickpea, there is a gradual lineardecline in yield with a delay in sowing from early November to mid-December.However, there are instances of poor yields with early sowing and high yieldswith sowing in December, depending on the relative incidence of the biotic andabiotic stresses that affect chickpea. If these can be adequately managed, highyields are also possible with December sowing. The advent of direct seeding ofrice and the use of short-duration rice varieties widen the sowing window anddecrease the cultivation risk of chickpea and other rabi crops. A wider range ofcropping options becomes possible, thus diversifying the risk associated withany one crop.The possibilities for genetic improvement of chickpea for the High Barind Tract(HBT) were considered by soliciting farmer feedback on their preferences for traitsand varieties through a participatory varietal selection (PVS) program. A farmer-researcherideotype was thus formulated suggesting the traits required to improve uponthe currently most preferred chickpea variety in the region, BARI chola 5. Such traitsincluded shorter duration and tolerance of cold, drought, soil fungal diseases, and Helicoverpapod borer. However, continued cultivation of chickpea on the same land isnot recommended due to the inevitable buildup of chickpea diseases, and rotation withother rainfed rabi crops is required. The relative profitability of rainfed wheat, barley,rapeseed mustard, linseed, and coriander was compared in farmer-implemented trialsin operational-scale plots. Yields of all crops, including chickpea, varied markedly overspace and time, which could be attributed mainly to surface soil moisture status duringcrop establishment. It is suggested that this risk could be markedly reduced by usingmechanized minimum tillage with uniform seed placement, as would be possible withthe further development of seeders attached to power tillers. In favorable soil moistureIntegration of chickpea and other rabi crops into rainfed rice-based systems of the High Barind Tract 135
conditions, wheat, barley, and mustard could match the profitability of chickpea, andthus provide a viable option for diversifying rainfed rabi crops. Although increasedrabi cropping will improve livelihoods in the HBT, it is suggested that substantialimprovements will depend on diversification of the entire agricultural productionsystem (including vegetable production, animal husbandry, fisheries, forestry, etc.),with particular attention paid to improving water-use efficiency.The traditional cropping system of the HBT of Bangladesh has been rainfedrainy-season rice, cultivated during June to December, with the land remaining fallowfor the rest of the year (Hamid and Hunt 1987). The advent of deep tube wellirrigation in the 1980s has substantially increased postrainy-season (rabi) croppingopportunities in the HBT but it is currently estimated that this form of irrigation willnot extend to beyond 50% of the HBT area. Declining water tables suggest that theremay indeed be a decline in irrigated area in the future. Therefore, there is a large scopefor cropping in rice fallows, using mainly the residual soil moisture remaining afterthe harvest of rice.Integrating other crops with rice into a rice-based cropping system is difficult.Soil conditions conducive to rice cultivation are unfavorable to crops requiring anaerobic root environment. With annual plowing and soil puddling for rainfed ricecultivation, a hard pan with high bulk density and low permeability to water developsat 10–15-cm depth. On the one hand, this hard pan helps retain water at the surfacefor rice cultivation but, on the other hand, it impedes root penetration of other crops(Samson and Wade 1998). Deep plowing to improve root penetration of aerobic cropswould be detrimental to maintaining flooded conditions for subsequent rice crops.However, when surface soil in the HBT remains moist, at or near field capacity, it ispossible for roots of some rabi crops, such as chickpea (Cicer arietinum L.), to readilypenetrate the hard-pan layer and reach depths of >1 m, despite the high bulk densityof the hard-pan layer as well as the soil at deeper layers (Ali et al 2002).Another difficulty in establishing a rainfed rice-rabi crop system is that the durationof the rice crop often extends beyond the optimum time for planting of the rabi crop.Swarna is currently the most common rice variety grown in the HBT in the rainy seasonand it is normally harvested in late November or early December. Optimum plantingtime for most rabi oilseed and pulse crops in Bangladesh is considered to be beforemid-November (Huda and Hussain 1989). Delayed sowing of these crops results inyield penalties due to limited biomass formation before the winter period when growthis minimal (December-January) and receding residual moisture from the soil surface. Afurther problem in establishing rice-rabi cropping systems is that rice, being the majorstaple food crop, attracts disproportionately more economic incentives, infrastructuresupport, and research attention than rabi crops with which it can be grown in rotation,ultimately discouraging the cultivation of rainfed rabi crops.The purpose of this paper is to examine some of the major constraints to developingrainfed rice-rabi cropping systems in the HBT and to suggest means of overcomingthese constraints. Chickpea has proven to be the most suitable rainfed rabi crop tofollow rice (Islam et al 1994) but, in order to diversify the system, prospects of otherrabi crops will also be examined.136 Johansen et al
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Improving AgriculturalProductivity
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Bangladeshi experiences with a drum
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AcknowledgmentsIRRI is most gratefu
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The High Barind Tract: a challengin
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irrigation across the entire Barind
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Workshop synthesis
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and, with representatives from the
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Subsistence pressureLand pressure,
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HerbicidesEarlier efforts to introd
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volume). PVS is an effective way to
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Farmers may use wet-seeded DSR as a
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process and distributing HNPV to fa
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an NGO, have successfully collabora
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Workshop discussionParticipants dis
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How can we identify a short-duratio
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to fixed tenancy. The implication i
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Opportunities for improving ricepro
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that the reliability and productivi
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Table 1. Planting dates, direct-see
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Table 2. (A) Mean effect of fertili
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Table 5. On-farm trials of a drum s
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Upper toposequenceYield (t ha -1 )7
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and perennial grasses (e.g., Ischae
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Direct-seeded rice in the HighBarin
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Table 1. Sample selection for costs
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Table 4. Variations in weed managem
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Table 7. Labor requirements (days h
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Table 10. Farmer perceptions of dis
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Farmers (no.)1412108DSRWet-seededDr
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able commercially. Other OFT farmer
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Box 1. Farmers’ comments on DSRPo
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NotesAuthors’ addresses: M.A. Jab
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This paper explores the role of som
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(Olsen method, atomic absorption),
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Mean biomass (g m −2 )1,000.000Fi
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Fig. 3. Log rank abundance of weed
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attested by Fig. 2). Diversity in t
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Bangladeshi experiences with a drum
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Table 1. Grain yield and crop durat
Page 92 and 93: Table 5. Grain yield and growth dur
Page 94 and 95: ACEy = 0.0001x + 0.7089Yield (t ha
Page 96 and 97: Table 11. Partial budget analysis f
Page 98: ConclusionsDirect wet-seeded rice u
Page 101 and 102: A 178% increase in rice production
Page 103 and 104: Table 1. Components of yield gaps d
Page 105 and 106: Table 3. Weed management in Comilla
Page 107 and 108: Table 5. Weed management practices
Page 109 and 110: Table 7. Significance (P H o ) of t
Page 111 and 112: Since 2000, there has been an incre
Page 114 and 115: Identifying varieties for the High
Page 116 and 117: Table 1. Rice varieties bred by cli
Page 118 and 119: Table 2. Grain yield advantage of J
Page 120 and 121: Table 3. Plant height and crop dura
Page 122 and 123: Table 6. Summary of adoption and sp
Page 124 and 125: Freeman GH, Perkins J.M. 1971. Envi
Page 126: Opportunities for improving rabi cr
Page 129 and 130: Grain yield (t ha -1 )2.0npp1.5LSD
Page 131 and 132: In each of the plots, numbers of He
Page 133 and 134: Table 2. Effect of IPM components o
Page 135 and 136: Unit plot size was 10 10 m and the
Page 137 and 138: Yield (t ha -1 )5Straw4321GrainP (g
Page 139 and 140: Nodulation score3AControl Soil Mo P
Page 141 and 142: even at low levels of production. B
Page 146 and 147: Grain yield (t ha -1 )3.02.51989-99
Page 148 and 149: Improved Improved Rainfed rainfed C
Page 150 and 151: Table 1. Preharvest and postharvest
Page 152 and 153: Greater resistance to Helicoverpa p
Page 154 and 155: wheat varieties). There is also sco
Page 156 and 157: Developing seed systems fordissemin
Page 158 and 159: This paper describes attempts to em
Page 160 and 161: seed needed to attain the recommend
Page 162 and 163: introduced to permit sale beyond th
Page 164: pesticides, inoculation with benefi
Page 168 and 169: for the rabi crop in 2001. Hence, b
Page 170: where farmers decided not to relay-
Page 174 and 175: Table 2. Mean dates of T. aman harv
Page 176 and 177: Table 4. Subsistence pressure and r
Page 178 and 179: Table 7. Subsistence pressure and r
Page 180 and 181: cite the absence of rent as a facto
Page 182 and 183: abi cropping in the HBT through ear
Page 184 and 185: Formulation and dissemination ofimp
Page 186 and 187: in India, for which shorter-duratio
Page 188 and 189: Applied researchOFTsAdaptive resear
Page 190 and 191: Table 1. Recommended package of pra
Page 192 and 193: Table 2. Grain yields (kg ha -1 ) o
Page 194 and 195:
Table 4. Grain yields (t ha -1 ) of
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Table 6. Mean grain yields (t ha -1
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constraints present. This in itself
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Extending rabi cropping in rice fal
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Table 1. Estimates of rice area dur
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Yield (kg ha -1 )1,2001,00080060040
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Future disseminationThrough dialogu
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Direct seeding of rice andopportuni
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Table 1. Time of establishment and
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Table 3. Weed density and biomass a
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than in Central Java and many farme
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Proportion abundance (log scale)Ran
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CAN FIELD BE DRAINED?YesCAN FIELD B
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Johnson DE, Mortimer AM. 2005. Issu
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Zhao DL, Atlin GN, Bastiaans L, Spi
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