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1.
The acidic condition of soil intervened crop growth, especially for rice crop. This research aimed to examine whether application of SRI method on saline soil can improve the productivity of rice. This research applied SRI method in the hinterland of mangrove forest areas around Segara Anakan Lagoon of Indonesia through modified irrigation to reduce saline water intrusion. SRI along with deep furrows in this first implementation had reduced the use of synthetic fertilizers by 40%, reduced variable costs by 8.35%, increased the B/C ratio by 95% and crop productivity by 76% compared to the control methods and increased the B/C ratio by 161% and crop productivity by 133% compared to conventional methods. The farmer’s motivation to apply SRI along with deep furrows for both N-Ach and N-Aff majority was distributed from moderate to high. 相似文献
2.
Mustapha Ceesay 《Paddy and Water Environment》2011,9(1):129-135
Promising results from an increasing number of field evaluations of the System of Rice Intensification (SRI) conducted in
Asia and Africa indicate that African farmers could increase their rice production while lowering costs of operation and reducing
the need for water by utilizing its principles and practices. This system relies not on external inputs to raise productivity
but on alternative methods for managing rice plants and the soil and water resources devoted to their cultivation. Farmers
in sub-Saharan Africa increasingly have to cope with the impacts of adverse climate effects because water shortages and long
dry spells during the cropping season are becoming common, even in lowland rice agroecosystems. SRI management practices create
both larger rice root systems that make their plants more resistant to biotic and abiotic stresses and more conducive environments
for beneficial soil microflora and fauna to flourish. Better plant growth and development result from promoting plant–soil
synergies. Controlled fertilizer management experiments conducted with SRI practices in The Gambia have showed that grain
production can be significantly increased without higher application of inorganic fertilizer and with less requirement for
water. SRI management practices with fertilizer application at the national recommended dose produced a grain yield of 7.6 t ha−1. Water productivity was greatly increased, with 0.76 g of grain produced per kg total water input, compared to 0.10 g of
grain per kg of water when the crop was continuously flooded. Recent hikes in fuel prices and consequent rises in input costs
are making domestic rice production less attractive and importation even more attractive. Computation of production costs
showed that SRI production, not needing heavy applications of fertilizer, is economically cost-effective. Achieving yield
increases through ever-higher fertilizer applications is not economically or environmentally viable. SRI management with recommended
fertilizer applications produced a net return of $853 ha−1 compared to $853 ha−1 compared to 37 when using farmers’ present low-productivity practices. 相似文献
3.
A field experiment was conducted in 2005 to investigate the effects of modified rice cultivation methods on: water use efficiency,
the uptake of nutrients (N, P and K) by plants, and their distribution within plants and their internal use efficiency. The
treatments were modified methods of irrigation, transplanting, weeding, and nutrient management, comparing the System of Rice
Intensification (SRI) with standard rice-growing methods including traditional flooding (TF). Results showed that the uptake
of N, P, and K by rice plants during their growth stages was greater with SRI management compared to TF, except during the
tillering stage. At maturity stage, SRI plants had taken up more nutrients in their different major organs (leaves, stems,
and sheaths; panicle axis; and seeds), and they translocated greater amount of nutrients to the grain. Under SRI, the ratio
of N, P, and K in seed grain to total plant N, P, and K was 4.97, 2.00, and 3.01% higher, respectively, than with TF. Moreover,
under SRI management, internal use efficiency of the three macronutrients (N, P, and K) was increased by 21.89, 19.34, and
16.96%, respectively, compared to rice plants under TF management. These measurements calibrate the crop’s physiological response
to differences in cultural practices, including the maintenance of aerobic versus anaerobic environment in the root zones.
With SRI, irrigation water applications were reduced by 25.6% compared to TF. Also, total water use efficiency and irrigation
water use efficiency was increased with SRI by 54.2 and 90.0%, respectively. Thus, SRI offered significantly greater water
saving while at the same time producing more grain yield, in these trials 11.5% more compared to TF. 相似文献
4.
Irrigation management transfer (IMT) and system of rice intensification (SRI) practice in the Philippines 总被引:2,自引:2,他引:0
SRI practices can usually increase the yield of paddy without using special varieties of rice or chemicals. High yield of paddy can be simply achieved through the combination of transplanting single seedlings about 8–10 days old with just two leaves on 40 cm × 40 cm spacing, providing organic fertilizer, and intermittent irrigation. No pesticides are applied. Historically, integrated management of water and crop (particularly rice) in the Philippines, had its beginning with the Spaniards, but more formal events were recorded in the 1950s by Margate (1954) in “Rice: 100 Cavans (50 kg/cavan) per Hectare.” This was followed by the Water Management Manual released in the 1970s by the Asian Development Bank (ADB) and National Irrigation Administration (NIA). Recently, the Southern Philippines Irrigation Sector Project (SPISP), a joint ADB–NIA effort, has commenced trials with the system of rice intensification (SRI) practice. One of the most specific features of SRI is the intermittent irrigation system which requires assured water supply at necessary timing. It is easier to attain assured water supply on timely manner through irrigation management transfer (IMT) which encourages the empowerment of fair water distribution. This article analyzes the merit of IMT for SRI. 相似文献
5.
Strategies and engineering adaptions to disseminate SRI methods in large-scale irrigation systems in Eastern Indonesia 总被引:1,自引:0,他引:1
The system of rice intensification (SRI) developed in Madagascar has been controversial in part because there have been no
large-scale, long-term evaluations of the impact of its alternative methods. This paper summarizes experience with the dissemination
of SRI practices across eight provinces in Eastern Indonesia over nine seasons from 2002 to 2006 under a major irrigation
project. The Decentralized Irrigation System Improvement Project (DISIMP) was financed by the Japanese Government with project
management by a Nippon Koei consultant team. SRI has been introduced in Indonesia via several organizations and in different
parts of the country starting in 2000. The evaluation reported here, made by the DISIMP technical assistance team, is based
on data from 12,133 on-farm comparison trials that covered a total area of 9,429 ha. Under SRI management, average paddy yield
increase was 3.3 t/ha (78%). This was achieved with about 40% reduction in water use, 50% reduction in chemical fertilizer
applications, and 20% lower costs of production. The farmers whom DISIMP was assisting to take up SRI were usually cultivating
their paddy fields individually within irrigation systems where it was difficult to reduce water applications as recommended
for SRI. Accordingly, innovations had to be made in soil and water management to create relatively aerobic soil conditions
so that farmers could get the more productive rice phenotypes expected from SRI practice. This article describes the modifications
made to adapt SRI concepts, pointing to the value of introducing in-field ditches, which was confirmed through paddy tract
surveys. This experience and analysis showed how SRI methods could be utilized within irrigation systems where water management
was not (yet) tailored to SRI production practices. Subsequently, modifications in irrigation system management are being
made to be more supportive of SRI cultivation. 相似文献
6.
Much of the focus of agricultural improvement efforts in recent decades has been on modifying crops’ genetic potential more
than on improving cropping practices and production systems. Certainly, this genocentric approach has made significant contributions
to food production in certain parts of the world under the banner of “the Green Revolution.” Yields have been raised substantially
through varietal improvements and the increased use of inputs, including energy, agrochemicals, and delivering more water
to crops through irrigation technology. In the past two decades, however, gains from this strategy have decelerated, with
increasing economic and environmental costs of this input-dependent approach. Accordingly, there is reason to consider what
can be accomplished by making optimizing changes in crops’ growing environments both above ground and, especially, below ground.
The System of Rice Intensification (SRI) developed in Madagascar has been showing that, by modifying crop, soil, water and
nutrient management, it can under most of the circumstances evaluated thus far raise of the productivity of land, water, seeds,
capital, and labor used for irrigated rice production. This article summarizes and reflects on the evidence provided in the
preceding articles in this special issue. It draws on the scientific evaluations and field experience from Asia, Africa, and
Latin America to offer some conclusions about the methodology known as SRI. Since this methodology is still evolving, no final
assessment is possible. Much more research and evaluation remain to be done, and there will be further modifications and refinements
since making adaptations to local conditions is regarded as intrinsic to the methodology. Further improvements in SRI will
come from both researchers and farmers, with the latter considered as partners rather than simply adopters. This is consistent
with SRI’s representing a paradigm shift more than a fixed technology. The article identifies a number of areas for additional
research that can probably improve factor productivity still further. 相似文献
7.
Amod Kumar Thakur Rajeeb Kumar Mohanty Dhiraj U. Patil Ashwani Kumar 《Paddy and Water Environment》2014,12(4):413-424
The system of rice intensification (SRI) reportedly enhances yield with less water requirement. This claim was investigated to determine the effects of alternative cultivation methods and water regimes on crop growth and physiological performance. Treatment combinations compared SRI with the conventional transplanting system (CTS) using standard practices, evaluating both along a continuum from continuous flooding to water applications at 1, 3, 5, or 7 days after disappearance of ponded water (DAD), subjecting plants to differing degrees of water stress while reducing total water expenditure. SRI methods gave significant changes in plants’ phenotype in terms of root growth and tillering, with improved xylem exudation and photosynthetic rates during the grain-filling stage compared to CTS. This resulted in significant increases in panicle length, more grains and more filled grains panicle?1, greater 1,000-grain weight, and higher grain yield under SRI management. Overall, averaged across the five water regimes evaluated, SRI practice produced 49 % higher grain yield with 14 % less water than under CTS; under SRI, water productivity increased by 73 %, from 3.3 to 5.7 kg ha-mm?1. The highest CTS grain yield and water productivity were with the 1-DAD treatment (4.35 t ha?1 and 3.73 kg ha-mm?1); SRI grain yield and water productivity were the greatest at 3-DAD (6.35 t ha?1 and 6.47 kg ha-mm?1). 相似文献
8.
The effects of irrigation method, age of seedling and spacing on crop performance, productivity and water-wise rice production in Japan 总被引:4,自引:4,他引:0
A field experiment using system of rice intensification (SRI) techniques was conducted in Chiba, Japan during the 2008 rice-growing
season (May–September) with eight treatment combinations in a split–split plot design (S–SPD) to observe the potential of
SRI methods under the temperate climatic conditions in Japan. Intermittent irrigation with alternate wetting and drying intervals
(AWDI) and continuous flooding throughout the cropping season were the two main-plot factors, while the effects of age of
seedlings and plant spacing were evaluated as sub and sub–sub plot factors, respectively. The experiment results revealed
that the proposed AWDI can save a significant amount of irrigation water (28%) without reduced grain yield (7.4 t/h compared
with 7.37 t/h from normal planting with ordinary water management). Water productivity was observed to be significantly higher
in all combinations of practices in the intermittent irrigation plots: 1.74 g/l with SRI management and AWDI as compared to
1.23 g/l from normal planting methods with ordinary water management. In addition, the research outcomes showed a role of
AWDI in minimizing pest and disease incidence, shortening the rice crop cycle, and also improving plant stand until harvest.
Synergistic effects of younger seedlings and wider spacing were seen in tillering ability, panicle length, and number of filled
grains that ultimately led to higher productivity with better grain quality. However, comparatively better crop growth and
yields when using the same SRI practices with ordinary water management underscore a need for further investigations in defining
what constitute optimum wetting and drying intervals considering local soil properties, prevailing climate, and critical watering
stages in rice crop management. 相似文献
9.
System of rice intensification (SRI) is a water-saving agro-technique being popularized in Southern Asia including India. A particular key practice in SRI, reduced water application (no continuous flooding), needs to be more farmer-friendly for its mass adoption under traditional and non-traditional cultivation. A field experiment was conducted maintaining different water regimes throughout the crop season (vegetative as well as reproductive stages) by scheduling irrigation applications at 1, 3, or 5 days after disappearance of ponded water (DADPW), using two different plant spacings and two different varieties. With an increase in the period of water stress, tiller production was increased significantly (P ≤ 0.05) and found to be maximum under prolonged stress, i.e., 5 days after disappearance of ponded water (5 DADPW). Increased tiller production did not result in yield increments, but yield-contributing parameters (panicle weight, grain weight per panicle, filled grain percentage, and test weight) were confirmed as critical determinants of yield. Plant nutrient (NPK) uptake was reduced under stress conditions, but the translocation of phosphorus and potassium from sources to sink was increased significantly in this study. Nutrient utilization efficiency was also enhanced under mild (3 DADPW) to prolonged (5 DADPW) water stress conditions. No significant reduction in yield was recorded under mild water stress, and this resulted in increased water productivity; however, significant yield loss was observed under prolonged water stress (5 DADPW). 相似文献
10.
Niveta Jain Rachana Dubey D. S. Dubey Jagpal Singh M. Khanna H. Pathak Arti Bhatia 《Paddy and Water Environment》2014,12(3):355-363
System of rice intensification (SRI) is an alternate method of conventional puddled, transplanted, and continuously flooded rice cultivation for higher yield, water saving, and increased farmer’s income. The SRI may also have considerable impact on greenhouse gas emission because of difference in planting, water and nutrient management practices. A field experiment was conducted with three planting methods: conventional puddled transplanted rice (TPR), conventional SRI with 12-days-old seedling (SRI) and modified SRI with 18-days-old seedling (MSRI) to study their effect on methane and nitrous oxide emission. Seasonal integrated flux (SIF) for methane was highest in the conventional method (22.59 kg ha?1) and lowest in MSRI (8.16 kg ha?1). Methane emissions with SRI and MSRI decreased by 61.1 and 64 %, respectively, compared to the TPR method. Cumulative N2O–N emission was 0.69, 0.90, and 0.89 kg ha?1 from the TPR, SRI, and MSRI planting methods, respectively. An average of 22.5 % increase in N2O–N emission over the TPR method was observed in the SRI and MSRI methods. The global warming potential (GWP), however, reduced by 28 % in SRI and 30 % in MSRI over the TPR method. A 36 % of water saving was observed with both SRI and MSRI methods. Grain yield in the SRI and MSRI methods decreased by 4.42 and 2.2 %, respectively, compared to the TPR method. Carbon efficiency ratio was highest in the MSRI and lowest in the TPR method. This study revealed that the SRI and MSRI methods were effective in reducing GWP and saving water without yield penalty in rice. 相似文献
11.
Irrigation water reduction using System of Rice Intensification compared with conventional cultivation methods in Iraq 总被引:1,自引:1,他引:0
Khidhir Abbas Hameed Abdul-Kadhim Jawad Mosa Flayeh Abed Jaber 《Paddy and Water Environment》2011,9(1):121-127
A field study was conducted at Al-Mishkhab Rice Research Station (MRRS) during the summer season 2009 to evaluate irrigation
water use efficiency (IWUE) using Anbar 33 variety with the System of Rice Intensification compared to traditional methods.
During the growth phase, the number of leaves, stems, and roots, and the average plant height were measured every 15 days
for the two sets of methods. At maturity, the depth and length of plant roots was assessed, along with leaf area index (LAI)
of the flag leaf and plant height. The amount of irrigation water applied was measured by water meter for both methods. SRI
principles for plant age, spacing, etc., were implemented in the SRI plots. The results indicated more vigorous growth of
roots under SRI methods, reaching 13,004 cm plant−1 compared with non-SRI results of 4,722 cm plant−1. There was 42% increase in grain yield when SRI methods were used. These had water use efficiency (WUE) of 0.291 kg m−2 compared with WUE of 0.108 kg m−2 for non-SRI cultivation, almost a threefold difference. SRI practices reduced the need for irrigation water by 38.5%. 相似文献
12.
Marie-Soleil Turmel Juan Espinosa Le��n Franco Candelario P��rez Horacio Hern��ndez Eric Gonz��lez Guillermo Fern��ndez Carlos Rojas Daniel S��nchez Nicol��s Fern��ndez Manuel Barrios Joann K. Whalen Benjamin L. Turner 《Paddy and Water Environment》2011,9(1):155-161
On-farm trials were conducted to evaluate the potential of the System of Rice Intensification (SRI), a low-input crop management system, to increase rice yields and reduce water consumption on subsistence farms in several regions of Panama and to determine how inherent soil fertility might affect SRI yields and the yield response to SRI management in the first season of SRI management. SRI practices increased yield by 47% on average and showed potential to increase yield by over 90%, while reducing water consumption by as much as 86%. SRI yields were correlated with available soil K and the difference between SRI and the conventional system yields was positively correlated with extractable Ca, Mg and Mn. The results of this study indicate that SRI is a promising rice production system for smallholder farmers in rural Panama farming under Panamanian soil conditions. 相似文献
13.
Application of system of rice intensification practices in the arid environment of the Timbuktu region in Mali 总被引:1,自引:1,他引:0
Erika Styger Malick Ag Attaher Hamidou Guindo Harouna Ibrahim Mahamane Diaty Ibrahima Abba Mohamed Traore 《Paddy and Water Environment》2011,9(1):137-144
Cereal production is chronically deficit in the Timbuktu region of Mali, sufficient for only 4.5 months of annual household
consumption. Small-scale, village-based irrigation schemes, usually 30–35 ha in size, irrigated by a diesel motor pump, have
become important to improve food security in this arid region. The NGO Africare has worked during the past 12 years with farmers
in Goundam and Dire circles to establish irrigation schemes and provide them with technical assistance. In 2007, Africare
undertook a first test of the System of Rice Intensification (SRI) in Goundam circle. After farmers observed a yield of 9 t ha−1 of paddy compared to 6.7 t ha−1 in the control plot there was interest in larger scale testing of the SRI system. In 2008, Africare, in collaboration with
the local Government Agriculture Service and with support from the Better U Foundation, implemented a community-based evaluation
of SRI with 60 farmers in 12 villages. Farmers in each village selected five volunteers, who each installed both SRI and control
plots, side by side, starting the nurseries on the same day and using the same seed. For SRI plots, seedlings were transplanted
one plant hill−1 at the two-leaf stage (on average, 11.6 days old), with spacing of 25 cm × 25 cm between hills and aligned in both directions.
This allowed farmers to cross-weed with a cono-weeder, on average 2.4 times during the season. In the control plots, farmers
planted 3 plants hill−1 with seedlings 29.4 days old and spaced on average 23.7 cm, not planted in lines. Weeding was done by hand. 13 t ha−1 of organic matter was applied under SRI management, and 3 t ha−1 in the control plots. Fertilizer use was reduced by 30% with SRI compared to the control. Although alternate wetting and
drying irrigation is recommended for SRI, this was not optimally implemented due to constraints on irrigation management within
the scheme; thus water savings were only 10% compared to the control. Average SRI yield for all farmers reached 9.1 t ha−1, with the lowest being 5.4 t ha−1 and highest being 12.4 t ha−1. SRI yields were on average 66% higher than the control plots at 5.5 t ha−1, and 87% higher than the yields in surrounding rice fields at 4.9 t ha−1. Number of tillers and panicles hill−1, number of tillers and panicles m−2, and panicle length and number of grains panicle−1 were clearly superior with SRI compared to control plants. Farmers tested five varieties, all of which produced better under
SRI. The SRI system allowed for a seed reduction of 85–90%: from 40–60 kg ha−1 for the control plots to 6.1 kg ha−1 under SRI. Although production costs per hectare were 15% higher for SRI, revenue was 2.1 times higher than under the control.
Farmers were very satisfied with these results. In 2009/2010, Africare and the Government’s agriculture service worked with
over 270 farmers in 28 villages to scale up SRI practices and to test innovations, including composting techniques, optimization
of irrigation, and techniques to reduce labor requirements and production costs. The good crop performance along with other
advantages was confirmed in this third year with SRI yields of 7.7 t ha−1 (n = 130 farmers) compared to 4.5 t ha−1 in farmers’ fields. 相似文献
14.
Rishi Raj Anil Kumar I. S. Solanki Shiva Dhar Anchal Dass Ashish Kumar Gupta Vikash Kumar C. B. Singh R. K. Jat U. C. Pandey 《Paddy and Water Environment》2017,15(4):861-877
A field study on assessment of crop establishment methods on yield, economics and water productivity of rice cultivars under upland and lowland production ecologies was conducted during wet seasons (June–November) of 2012 and 2013 in Eastern Indo-Gangetic Plains of India. The experiment was laid-out in a split-plot design (SPD) and replicated four times. The main-plot treatments included three crop establishment methods, viz. dry direct-seeded rice (DSR), system of rice intensification (SRI) and puddled transplanted rice (PTR). In sub-plots, five rice cultivars of different groups like aromatic (Improved Pusa Basmati 1 and Pusa Sugandh 5), inbreds (PNR 381 and Pusa 834) and hybrid (Arize 6444) were taken for their evaluations. These two sets of treatments were laid-out simultaneously in two production ecologies, upland and lowland during both years. In general, lowland ecology was found favourable for rice growth and yield and resulted in 13.2% higher grain yield as compared to upland ecology. Rice grown with SRI method produced 19.4 and 7.0% higher grain yield in 2012 and 20.6 and 7.1% higher in 2013, over DSR and PTR. However, PTR yielded 13.1 and 14.5% higher grain over DSR during 2012 and 2013, respectively. On an average, Arize 6444 produced 26.4, 26.9, 28.9 and 54.7% higher grain yield as compared to PS 5, P 834, PNR 381 and IPB1, respectively. Further, the interaction of production ecologies × crop establishment methods revealed that, in upland ecology, SRI recorded significantly higher grain yield as compared to PTR and DSR, but in lowland, grain yield resulting from SRI was similar to the yield obtained with PTR and significantly higher than DSR. The latter two methods (PTR and DSR) yielded alike in lowland ecology in both study years. The production ecologies × crop establishment methods × cultivars interaction on grain yield showed that the growing of Arize 6444 cultivar using SRI method in upland ecology resulted in the higher grain yield (8.87 t/ha). But the cost of production was also highest in SRI followed by PTR and DSR across production ecologies and cultivars. Cultivation of hybrid (Arize 6444) involved higher cost of production than all other cultivars. Irrespective of crop establishment methods and cultivars, gross returns, net returns and B:C ratio were significantly higher in lowland compared to upland ecology. Owing to higher grain yield, SRI method fetched significantly higher gross returns and net returns over PTR and DSR. Average increase in net return with Arize 6444 was 68.8, 41.0, 37.7 and 33.1% over IPB 1, PNR 381, P 834 and PS 5, respectively. There was a saving of 30.7% water in SRI and 19.9% in DSR over PTR under upland ecology. Similarly in lowland ecology, water saving of 30.2% was observed in SRI and 21.2% in DSR over PTR. Due to higher yield and saving on water, SRI returned significantly higher total water productivity (TWP) (5.9 kg/ha-mm) as compared to DSR (3.5 kg/ha-mm) and PTR (3.6 kg/ha-mm) under upland ecology. In lowland ecology, also SRI (6.2 kg/ha-mm) resulted in higher TWP as compared to other two methods. However, DSR gave significantly higher TWP as compared to PTR. Among cultivars, hybrid Arize 6444 recorded the highest TWP in both upland and lowland production ecologies across crop establishment methods. Hence, growing of hybrid Arize 6444 with SRI method can enhance rice productivity and water-use efficiency in lowland and upland production ecologies of Eastern Indo-Gangetic Plains and in other similar regions. 相似文献
15.
Crop and water productivity as influenced by rice cultivation methods under organic and inorganic sources of nutrient supply 总被引:1,自引:0,他引:1
Y. V. Singh 《Paddy and Water Environment》2013,11(1-4):531-542
A field experiment was conducted during the wet seasons of 2010 and 2011 at New Delhi, India to study the influence of organic, inorganic, and integrated sources of nutrient supply under three methods of rice cultivation on rice yield and water productivity. The experiments were laid out in FRBD with nine treatment combinations. Treatment combinations included three sources of nutrient supply viz., organic, integrated nutrient management, and inorganic nutrition and three rice production systems viz., conventional transplanting, system of rice intensification (SRI) and aerobic rice system. Results indicated that the conventional and SRI showed at par grain and straw yields but their yields were significantly higher than aerobic rice. Grain yield under organic, inorganic and integrated sources of nutrient supply was at par since the base nutrient dose was same. Plant growth parameters like plant height, tillers, and dry matter accumulation at harvest stage were almost same under conventional and SRI but superior than aerobic rice system. Root knot nematode infestation was significantly higher in aerobic rice as compared to SRI and conventional rice. However, organic, inorganic and integrated sources of nutrient supply did not affect nematode infestation. There was significant advantage in term of water productivity under SRI over conventional transplanted (CT) rice and less quantity of water was utilized in SRI for production of each unit of grain. A water saving of 34.5–36.0 % in SRI and 28.9–32.1 % in aerobic rice was recorded as compared to CT rice. 相似文献
16.
Local governments, NGOs, system of rice intensification (SRI) adopters, and researchers in Cambodia have extensively discussed the SRI. Agreement on the benefits, however, remains elusive. Some claim SRI increases rice yields at lower costs; others state that the evidence is still inconclusive. The adoption and impact of innovations influenced by the most practical SRI principles, which adopters can and do implement, as well as other SRI labor requirement have yet to be comprehensively investigated. This study aimed at elucidating and comparing distinct aspects of SRI labor requirements and conventional practices that can lead to more intensive SRI adoption. A household survey and field observations were conducted in three rain-fed villages in the southern part of Cambodia: two in Kampot Province and one in Kampong Speu Province. Findings showed little or no difference between SRI labor requirements and conventional practices. Laborers are in high demand when preparing land and nurseries, transplanting seedlings, and harvesting. Rice farmers alone or hired laborers have generally proved sufficient to date. Hired labor costs depend on the supply of farmer-family labor and the efficacy of the “Sharing-hand” system, not on farming techniques per se. This system helps alleviate hired labor costs, one of the highest cost factors. The findings also indicated that the degree of SRI adoption shows no correlation between the home-to-plot distance and availability of farmer-family labor or hired labor. The key factors for improving the degree of SRI adoption are farmer zeal and careful attention rather than the home-to-plot distance and availability of labor. 相似文献
17.
18.
Priyanka Suryavanshi Y. V. Singh R. Prasanna Arti Bhatia Y. S. Shivay 《Paddy and Water Environment》2013,11(1-4):321-329
Methane (CH4) emission and water productivity were estimated in an experiment conducted during wet (rainy) season of 2010 at the research farm of Indian Agricultural Research Institute, New Delhi, India. Treatments comprising three methods of crop establishment viz., conventional transplanting (CT), system of rice intensification (SRI) and double transplanting (DT) were laid out in randomized block design with four replications. Scented rice (Oryza sativa L) variety ‘Pusa Basmati 1401’ was transplanted in puddle field. In CT and SRI 21 and 12-day-old seedlings, respectively, were transplanted while in DT overall 45-day-old seedlings were transplanted. In CT and DT flooded conditions while in SRI saturated conditions were maintained. Results indicated that among the methods of crop establishment, CT had maximum cumulative CH4 emission (32.33 kg ha?1) followed by DT (29.30 kg ha?1) and SRI (19.93 kg ha?1). Temporal CH4 flux fluctuated between 79.7 and 482.0 mg m?2 day?1 under CT; 46.0 and 315.0 mg m?2 day?1 in SRI and 86.7 and 467.3 mg m?2 day?1 in DT. Considerable temporal variations in the individual CH4 fluxes were observed. Flux of CH4 was generally higher in early stage of crop and peaked about 21 days after transplanting coinciding with tillering stage of crop. CH4 flux declined gradually from 75 days after transplanting and stabilized at the harvest stage of rice in all the three methods of transplanting. Global warming potential was highest in CT (807.4 kg CO2 ha?1) and lowest in SRI (498.25 kg CO2 ha?1). However, a reverse trend was observed with carbon efficiency ratio. The water savings to the extent of six irrigations was recorded in SRI over CT. A saving of 27.4 % irrigation water and 18.5 % total water was recorded in SRI over CT while the corresponding values of DT over CT were 14.5 and 9.8 %. Water productivity of SRI (3.56 kg/ha mm) was significantly higher as compared to DT (2.87 kg/ha mm) and CT (2.61 kg/ha mm). 相似文献
19.
Improving irrigation performance is a crucial issue for agriculture and irrigation development in the Lower Mekong River Basin
to secure food production for people’s livelihoods. Irrigation efficiency is the most important indicator to determine the
performance of an irrigation scheme. This study looks at water management practices and irrigation efficiency in three pilot
sites in the Lower Mekong River Basin: the Numhoum scheme in Laos, the Huay Luang scheme in Thailand, and the Komping Pouy
scheme in Cambodia. Irrigation efficiency and water productivity were analyzed using a water balance approach at the irrigation
scheme level and results in the pilot areas show efficiencies that are definitely higher using this approach than by using
the classical concept. Lower water productivity was observed at pilot schemes in areas of single cropping and higher productivity
in areas where multiple agricultural activities were practiced. Strict and active water management is required to control
and save water to meet agricultural demand and have sufficient water to expand cultivation areas while avoiding shortages.
Promoting multiple uses of water for various agricultural activities in command area will increase water productivity.
相似文献
Hiroshi OkudairaEmail: |
20.
A field experiment was conducted to investigate the effects of intermittent versus continuous irrigation, together with different
degrees of organic fertilization, on the growth and yield of hybrid rice, looking also at the functioning of the rhizosphere
as this is a key element affecting crop performance. The crop management practices employed generally followed the recommendations
of the System of Rice Intensification (SRI). The aim of the research was to learn how water management and organic fertilization
together would affect crop outcomes. Under intermittent water application as recommended with SRI management (aerobic irrigation,
AI), grain yield increased by 10.5–11.3%, compared to standard irrigation practice (continuous flooding, CF). The factor that
contributed most to higher yield was increased number of grains per panicle. It was seen that under the range of organic fertilization
treatments evaluated, intermittent irrigation compared with CF promoted greater dry matter production and higher leaf area
index (LAI) during the main growth stages. Also, the combination of intermittent irrigation and organic material applications
significantly increased soil redox potential (Eh), compared with CF, and also the numbers of actinomycetes in the rhizosphere
soil. Actinomycetes were evaluated in this study as an indicator of aerobic soil biota. It was seen that with intermittent
irrigation, the application of organic material improved the functioning of the rhizosphere and increased yield. However,
these results based on 2 years of study reflect relatively short-term effects. The effects of longer-term water management
and soil fertilization regimes should be also examined, to know whether these effects continue and, if they do, whether they
become greater or less. 相似文献