It is known that cropping causes soil carbon loss, which is a critical issue, especially in tropical agriculture. Nitrogen input generally increases net primary production but does not increase soil carbon content bec...It is known that cropping causes soil carbon loss, which is a critical issue, especially in tropical agriculture. Nitrogen input generally increases net primary production but does not increase soil carbon content because nitrogen input enhances soil organic carbon mineralization by microorganisms. A farmer conducted a trial in which he applied material with a high carbon:nitrogen (C:N) ratio without additional nitrogen fertilizer, and achieved a higher productivity than that of conventional farms. Based on his results, we conducted a survey to evaluate the effects of high C:N ratio organic material on the productivity, soil profile, microbial activity, and carbon and nitrogen balance of soil. Results demonstrate that high C:N ratio organic material enhanced the formation of the soil A horizon and increased soil carbon and nitrogen content. Approximately, 15 - 20 t·ha-1·crop-1 of fresh waste mushroom bed was applied to 15 crops over 4.5 years, and the total input of carbon and nitrogen were 5014 and 129 g·m-2, respectively. The soil nitrate nitrogen concentration was the same as that of the neighboring forest soil, which was lower than the standard limit for conventional agriculture;however, the average productivity of crops was approximately four times that of the national average. The soil Ap horizon increased in thickness by 7 cm, and aggregates reached a thickness of 29 cm in 4.5 years. The output/input ratios of total soil nitrogen and carbon were approximately 2.68 - 6.00 and 1.30 - 2.35, respectively, indicating that this method will maintain the carbon and nitrogen balance of the system. The observed soil microbial activity was one order of magnitude higher than that of a fallow field. The results indicate that this agricultural method remediates soil degradation, and improves food production.展开更多
Many tree planting programmes have long been initiated to increase forest cover to mitigate the effects of global climate change.Successful planting requires careful planning at the project level,including using suita...Many tree planting programmes have long been initiated to increase forest cover to mitigate the effects of global climate change.Successful planting requires careful planning at the project level,including using suitable species with favourable traits.However,there is a paucity of improvement data for tropical tree species.An experimental common garden of Shorea leprosula was established to study traits related to growth performance which are key factors in planting success.Seedlings of S.leprosula were collected from nine geographical forest reserves.To study the effects of genetic variation,seedlings were planted in a common environment following a randomized complete block design.From performance data collected 2017‒2019,one population showed the highest coefficient for relative height growth,significantly higher than most of the other populations.Interestingly,this population from Beserah also exhibited the lowest coefficient for scale insect infestation.This study provides preliminary results on growth performance and susceptibility to scale insect infestation in S.leprosula and the first common garden experiment site conducted on dipterocarp species.It lays a foundation for future genome-wide studies.展开更多
Iron toxicity is a major constraint to rice production, particularly in highly weathered soils of inland valleys in Sub-Saharan Africa where the rice growing area is rapidly expanding. This study aimed to improve the ...Iron toxicity is a major constraint to rice production, particularly in highly weathered soils of inland valleys in Sub-Saharan Africa where the rice growing area is rapidly expanding. This study aimed to improve the productiveness of iron toxicity sensitive’s rice fields as well as in the unsensitive fields by using local phosphate fertilizers. Eighteen (18) rice genotypes were been assessed in a split plot design in two areas: without iron toxicity and with iron toxicity. NPK, NK, Rock Phosphate, Triple super phosphate, Calcined phosphate and Acidulated phosphate were used as fertilizers. Data collection was focused on agronomic traits and yield (g/m<sup>2</sup>). The best fertilizers in the area without iron toxicity were NPK (820.2 g/m<sup>2</sup>) and triple super phosphate (751.7 g/m<sup>2</sup>). In the iron toxicity area, the best yields were performed by NPK (785.5 g/m<sup>2</sup>) and raw calcined phosphate (698.3 g/m<sup>2</sup>). Yet, the Accessions 15, Accessions 225, Accessions 226 and Accessions 270 were rainfed rice genotypes while CC109 A, HB 46 and HB 62 were low-land/irrigated rice genotypes. NPK, NK and acidulated phosphate fertilizers alleviate the best, iron toxicity in both sensitive and unsensitive rice fields.展开更多
This paper estimates a stochastic frontier function using a panel data set that includes 4 961 farmer households for the period of 2005-2009 to decompose the growth of grain production and the total factor productivi...This paper estimates a stochastic frontier function using a panel data set that includes 4 961 farmer households for the period of 2005-2009 to decompose the growth of grain production and the total factor productivity （TFP） growth at the farmer level. The empirical results show that the major contributor to the grain output growth for farmers is input growth and that its average contribution accounts for 60.92% of farmer’s grain production growth in the period of 2006-2009, whereas the average contributions sourced from TFP growth and residuals are only 17.30 and 21.78%, respectively. The growth of intermediate inputs is a top contributor with an average contribution of 44.46%, followed by the planted area （18.16%）, investment in fixed assets （1.05%）, and labor input （-2.75%）, indicating that the contribution from the farmer’s input growth is mainly due to the growth of intermediate inputs and that the decline in labor inputs has become an obstacle for farmers in seeking grain output growth. Among the elements consisting of TFP growth, the contribution of technical progress is the largest （32.04%）, followed by grain subsidies （8.55%）, the average monthly temperature （4.26%）, the average monthly precipitation （-0.88%）, the adjusted scale effect （-5.66%）, and growth in technical efficiency （-21.01%）. In general, the contribution of climate factors and agricultural policy factor are positive and significant.展开更多
To enhance the yield potential of an elite indica rice cultivar,an introgression(BC_3-derived) line of IR64,YTH288,was developed using a new-plant-type cultivar,IR66215-44-2-3,as a donor parent.YTH288 has agronomicall...To enhance the yield potential of an elite indica rice cultivar,an introgression(BC_3-derived) line of IR64,YTH288,was developed using a new-plant-type cultivar,IR66215-44-2-3,as a donor parent.YTH288 has agronomically valuable characteristics such as large panicles,few unproductive tillers,and large leaves inherited from NPT.To identify the genetic basis of these traits,we used 167 F_2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits:days to heading(DTH),culm length(CL),flag leaf length(FLL),flag leaf width(FLW),and filled spikelet number per panicle(FSN).Six putative QTL were detected:four on chromosome4(for CL,FLL,FLW,and FSN) and two on chromosome 2(for DTH and FLL).All QTL with the IR66215-44-2-3 allele,except that for FLL on chromosome 2,had positive effects on each trait.To confirm the effects of these putative QTL,we developed NILs with the IR64 genetic background by marker-assisted selection.We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes2 and 4.Additionally,four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropic To enhance the yield potential of an elite indica rice cultivar, an introgression(BC3-derived) line of IR64, YTH288, was developed using a new-plant-type cultivar,IR66215-44-2-3, as a donor parent. YTH288 has agronomically valuable characteristics such as large panicles, few unproductive tillers, and large leaves inherited from NPT.To identify the genetic basis of these traits, we used 167 F2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits: days to heading(DTH), culm length(CL), flag leaf length(FLL), flag leaf width(FLW), and filled spikelet number per panicle(FSN). Six putative QTL were detected: four on chromosome4(for CL, FLL, FLW, and FSN) and two on chromosome 2(for DTH and FLL). All QTL with the IR66215-44-2-3 allele, except that for FLL on chromosome 2, had positive effects on each trait. To confirm the effects of these putative QTL, we developed NILs with the IR64 genetic background by marker-assisted selection. We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes2 and 4. Additionally, four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropiceffects for unique agronomic traits. These NILs can be used as research materials for studying each trait and as breeding materials for yield improvement of indica rice cultivars.展开更多
Increasing rice yield potential is a continuous challenge posed by world population growth.To increase yield potential,favorable alleles of valuable genes need to be accumulated in promising germplasm.We conducted com...Increasing rice yield potential is a continuous challenge posed by world population growth.To increase yield potential,favorable alleles of valuable genes need to be accumulated in promising germplasm.We conducted comparative yield trials for two years in Tsukuba,Japan,in a temperate region and at the International Rice Research Institute(IRRI),Philippines,in a tropical region using five high-yielding rice cultivars:Takanari and Hokuriku193,developed in Japan,and IR64,NSIC Rc158,and YTH183,developed in the Philippines.Genotype plus genotype×environment interaction(GGE)biplot analysis across four environments(two regions×two seasons)classified the five cultivars into four categories:Takanari and YTH183 showed high adaptability to both tropical and temperate regions,Hokuriku193 was suitable for temperate regions,NSIC Rc158 was suitable for the tropics,and IR64 was inferior to the other cultivars in both regions.The high yield and adaptability in Takanari and YTH183 were attributed to their large sink capacity with good grain filling.The plant type for high yield was different,however,between the two cultivars;Takanari was a panicle-weight type,whereas YTH183 was a panicle-number type.Evaluations of F2 progeny of a cross between Takanari and YTH183 showed transgressive segregation for number of panicles per plant as well as number of spikelets per panicle,leading some F2 plants to produce more spikelets per plant(corresponding to larger sink size)than the parental cultivars in both regions.These results suggest the possibility of developing rice cultivars with high yield potential in both temperate and tropical regions by crossing temperate with tropical high-yielding cultivars.展开更多
Phospho compost application is important with respect to soil fertility and plant nutrition. Therefore, the objective was to evaluate the influence of phospho compost application on P availability and uptake by maize ...Phospho compost application is important with respect to soil fertility and plant nutrition. Therefore, the objective was to evaluate the influence of phospho compost application on P availability and uptake by maize in red soil. The phosphorus applied in the form of phospho compost, as compare to rock phosphate and super phosphate at a rate of 50 and 100 mg P2O5 Kg-1 soil. The application was done as spot and mix application. Results indicate that, spot application of 100 mg P2O5 kg-1 soil as phospho compost (b) registered significantly higher P uptake (2.1 and 5.31 mg·pot-1) and available soil P (19.1 and 21.0 mg·kg-1) as compare to Rock Phosphate alone (0.60 and 0.97 mg·pot-1) and (5.6 and 6.0 mg·kg-1) at 30 and 60 day after sowing, respectively. The probable chelating effect from phospho composting increased the phosphorus use efficiency and resulted into higher relative agronomic efficiency in phospho compost (b) spot application (40%) over mix application (15%). The dry matter yield had positive and significant correlation with available P in soil and P uptake by maize plants at 30 and 60 day after sowing. Results concluded that phospho compost enriched with FYM was most effective in increasing phosphorus availability in red soil and increasing dry matter yield of maize plants.展开更多
Field performance of whitebacked planthopper （WBPH）-resistance of four phenotypes was evaluated in Chunjiang 06 （C J-06） / TN1 DH rice lines, which were expressed by different combinations of sucking inhibitory an...Field performance of whitebacked planthopper （WBPH）-resistance of four phenotypes was evaluated in Chunjiang 06 （C J-06） / TN1 DH rice lines, which were expressed by different combinations of sucking inhibitory and ovicidal traits inherited independently from C J-06. WBPH established the highest populations in susceptible DH lines that had neither sucking inhibitorynor ovicidal resistance. Both immigration and subsequent population levels were kept below the damage-causing density in the sucking inhibitory DH lines even under a WBPH outbreak. WBPH could not build up populations in the DH lines having both the sucking inhibitory and ovicidal resistance. Although WBPH immigrated preferentially to non-sucking inhibitory DH lines with ovicidal resistance, subsequent population buildup was significantly suppressed. It was concluded that the differential performance to WBPH-resistance in CJ-06 / TN1 DH lines was primarily due to the sucking inhibitory trait, and complementarity to the ovicidal trait.展开更多
Teak (Tectona grandis L.) plantation management is said to be profitable, but small-scale farmers with teak plantations need to find appropriate and effective choices for plantation management because of their small p...Teak (Tectona grandis L.) plantation management is said to be profitable, but small-scale farmers with teak plantations need to find appropriate and effective choices for plantation management because of their small plots. There have been few studies on how combinations of site quality, rotation and plant spacing affect financial evaluations of teak plantation management quantitatively. In this study, we introduced the yield table for teak plantations in Northeast Thailand, and investigated the effects of site quality with rotation (15-year and 20-year) and spacing (2 m × 4 m and 4 m × 4 m) on the financial evaluation of teak plantation management using discounted cash flow analysis. The equivalent annual incomes (EAI) and benefit/cost ratios (BCR) were negative and <1, respectively, at site indexes (SI) of 14 and 18, but increased ~2 - 3 times as SI rose from 22 (site of medium quality) to 26 and 26 to 30. The 20-year rotation was generally preferable to the 15-year one, especially at SI 22. At SI 30, 2 m × 4 m was more profitable than 4 m × 4 m for both rotations, but at SI 22, 20-year rotation with 4 m × 4 m was the most profitable, followed by 20-year with 2 m × 4 m.展开更多
The original online version of this article (Noda, I. et al. (2014). Effects of Silvicultural Alternatives on Model-Based Financial Evaluation of Teak (Tectona grandis L.) Farm Forestry Management for Small-Scale Farm...The original online version of this article (Noda, I. et al. (2014). Effects of Silvicultural Alternatives on Model-Based Financial Evaluation of Teak (Tectona grandis L.) Farm Forestry Management for Small-Scale Farmers in Northeast Thailand. Open Journal of Forestry, 4, 558-569. http://dx.doi.org/10.4236/ojf.2014.45060) was published in October. The author wishes to correct Table 5.展开更多
Substantial potential exists to expand supplies of biomass for energy applications through more systematic collection of agricultural residues, more intensive cultivation of croplands, and reduced waste and losses in ...Substantial potential exists to expand supplies of biomass for energy applications through more systematic collection of agricultural residues, more intensive cultivation of croplands, and reduced waste and losses in the food chain. This study aims to show how the potential can be calculated from public information sources, to put the potential in the context of global needs for liquid transport fuels, and to suggest some practical policy options for bringing part of the potential to market. It finds that if the theoretical potential is fully realized, enough liquid biofuel could be produced to displace the equivalent of all current global liquid fuel use for transport.展开更多
Physiological responses were studied in temperature-controlled glass house at Okinawa, Japan to evaluate drought and high temperature resistances of cowpea cultivar/strains for Sahel, Africa. Four drought-tolerant cow...Physiological responses were studied in temperature-controlled glass house at Okinawa, Japan to evaluate drought and high temperature resistances of cowpea cultivar/strains for Sahel, Africa. Four drought-tolerant cowpea cultivar/strains （cv. TVu-11986; TVu-11979; IT-96D-604 and Dan Ilia）, and three sensible strains （cv. IT96K-238-3, IT96K-231-1 and TVu-7778） were grown in pots and imposed to drought （soil content; 9.7±1.9%（w/w））, high （30/26℃, day/night, 12/12 hour）, normal （27/23℃, control） and low （24/20℃） temperature conditions after flowering. Plant fresh weight reduced 80%, 26% and 1% by dry, high and low temperature, respectively. Stem diameter decreased 32% and 2% by dry and low temperature, respectively, but increased 5% by high temperature. Difference between the drought tolerant and sensible cultivars/strains, pre-evaluated by IITA, was explained by relationship between stem diameter and plant fresh weight with 77% of reliability. The 35% of misclassification were due to misjudgment of drought tolerant as sensible in dry plot. The stem diameter highly correlated with all parts of plant weight in all regimes except in dry treatment. Difference of the classification between IITA and our results may cause different survival strategy against drought. The cultivars/strains, evaluated as drought tolerant by IITA, might fatten up at early stage, and could avoid from drought at latter growing stage.展开更多
The bioconversion of lignocellulose has attracted global attention,due to the significant potential of agricultural and forestry wastes as renewable zero-carbon resources and the urgent need for substituting fossil ca...The bioconversion of lignocellulose has attracted global attention,due to the significant potential of agricultural and forestry wastes as renewable zero-carbon resources and the urgent need for substituting fossil carbon.The cellulosome system is a multi-enzyme complex produced by anaerobic bacteria,which comprises cellulases,hemicellulases,and associated enzymatic and non-enzymatic components that promote biomass conversion.To enhance their efficiency in degrading recalcitrant lignocellulosic matrices,cellulosomes have been employed to construct biocatalysts for lignocellulose bioconversion,such as consolidated bioprocessing and consolidated bio-saccharification.Hemicelluloses,the second most abundant polysaccharides in plant cell walls,hold valuable application potential but can also induce inhibitory effects on cellulose hydrolysis,thus highlighting the indispensable roles of hemicellulases within the cellulosome complex.This review evaluated current research on cellulosomal hemicellulases,comparing their types,abundance,and regulation,primarily focusing on eight known cellulosome-producing species of different origins.We also reviewed their growth conditions,their hemicellulose-degrading capabilities,and the inhibitory effects of hemicellulose on cellulosome-based lignocellulose saccharification.Finally,we proposed strategies for targeted enhancement of hemicellulase in cellulosomes to improve lignocellulose bioconversion in future studies.展开更多
cDNA libraries were constructed from the leaves of a rice (Oryza sativa L.) salt tolerancevariety Tesan抋i 2 growing in solutions with 150 mmol/L NaCl for 3 h or without salt stress. Three salt-responsive cDNA clones,...cDNA libraries were constructed from the leaves of a rice (Oryza sativa L.) salt tolerancevariety Tesan抋i 2 growing in solutions with 150 mmol/L NaCl for 3 h or without salt stress. Three salt-responsive cDNA clones, Ts1, Ts2 and Ts3 were isolated by differential screening. Northern blottinganalysis showed that the transcription levels of Ts1 and Ts2 increased within 3 h salt stress and kept onincreasing within 24 h, while the transcription level of Ts3 reached its peak within 3 h. Sequence analysisindicated that there were no homologies between the three cDNA clones and any known gene. The threecDNA clones were mapped using a doubled haploid (DH) population derived from an indica variety ZYQ8,which was a salt tolerance parent of Tesan抋i 2, with a japonica variety JX17. Ts1, Ts2 and Ts3 werelocated on chromosomes 1, 3 and 7, respectively. It was noted that Ts1, Ts2, and Ts3 were in or near theregions of major or minor salt tolerance quantitative trait loci (QTLs), which were mapped in the same DHpopulation in a parallel study.展开更多
文摘It is known that cropping causes soil carbon loss, which is a critical issue, especially in tropical agriculture. Nitrogen input generally increases net primary production but does not increase soil carbon content because nitrogen input enhances soil organic carbon mineralization by microorganisms. A farmer conducted a trial in which he applied material with a high carbon:nitrogen (C:N) ratio without additional nitrogen fertilizer, and achieved a higher productivity than that of conventional farms. Based on his results, we conducted a survey to evaluate the effects of high C:N ratio organic material on the productivity, soil profile, microbial activity, and carbon and nitrogen balance of soil. Results demonstrate that high C:N ratio organic material enhanced the formation of the soil A horizon and increased soil carbon and nitrogen content. Approximately, 15 - 20 t·ha-1·crop-1 of fresh waste mushroom bed was applied to 15 crops over 4.5 years, and the total input of carbon and nitrogen were 5014 and 129 g·m-2, respectively. The soil nitrate nitrogen concentration was the same as that of the neighboring forest soil, which was lower than the standard limit for conventional agriculture;however, the average productivity of crops was approximately four times that of the national average. The soil Ap horizon increased in thickness by 7 cm, and aggregates reached a thickness of 29 cm in 4.5 years. The output/input ratios of total soil nitrogen and carbon were approximately 2.68 - 6.00 and 1.30 - 2.35, respectively, indicating that this method will maintain the carbon and nitrogen balance of the system. The observed soil microbial activity was one order of magnitude higher than that of a fallow field. The results indicate that this agricultural method remediates soil degradation, and improves food production.
基金supported by the Government of Malaysia under the 10th and 11th Malaysia Plan.
文摘Many tree planting programmes have long been initiated to increase forest cover to mitigate the effects of global climate change.Successful planting requires careful planning at the project level,including using suitable species with favourable traits.However,there is a paucity of improvement data for tropical tree species.An experimental common garden of Shorea leprosula was established to study traits related to growth performance which are key factors in planting success.Seedlings of S.leprosula were collected from nine geographical forest reserves.To study the effects of genetic variation,seedlings were planted in a common environment following a randomized complete block design.From performance data collected 2017‒2019,one population showed the highest coefficient for relative height growth,significantly higher than most of the other populations.Interestingly,this population from Beserah also exhibited the lowest coefficient for scale insect infestation.This study provides preliminary results on growth performance and susceptibility to scale insect infestation in S.leprosula and the first common garden experiment site conducted on dipterocarp species.It lays a foundation for future genome-wide studies.
文摘Iron toxicity is a major constraint to rice production, particularly in highly weathered soils of inland valleys in Sub-Saharan Africa where the rice growing area is rapidly expanding. This study aimed to improve the productiveness of iron toxicity sensitive’s rice fields as well as in the unsensitive fields by using local phosphate fertilizers. Eighteen (18) rice genotypes were been assessed in a split plot design in two areas: without iron toxicity and with iron toxicity. NPK, NK, Rock Phosphate, Triple super phosphate, Calcined phosphate and Acidulated phosphate were used as fertilizers. Data collection was focused on agronomic traits and yield (g/m<sup>2</sup>). The best fertilizers in the area without iron toxicity were NPK (820.2 g/m<sup>2</sup>) and triple super phosphate (751.7 g/m<sup>2</sup>). In the iron toxicity area, the best yields were performed by NPK (785.5 g/m<sup>2</sup>) and raw calcined phosphate (698.3 g/m<sup>2</sup>). Yet, the Accessions 15, Accessions 225, Accessions 226 and Accessions 270 were rainfed rice genotypes while CC109 A, HB 46 and HB 62 were low-land/irrigated rice genotypes. NPK, NK and acidulated phosphate fertilizers alleviate the best, iron toxicity in both sensitive and unsensitive rice fields.
基金supported by Japan International Research Center for Agricultural Sciences
文摘This paper estimates a stochastic frontier function using a panel data set that includes 4 961 farmer households for the period of 2005-2009 to decompose the growth of grain production and the total factor productivity （TFP） growth at the farmer level. The empirical results show that the major contributor to the grain output growth for farmers is input growth and that its average contribution accounts for 60.92% of farmer’s grain production growth in the period of 2006-2009, whereas the average contributions sourced from TFP growth and residuals are only 17.30 and 21.78%, respectively. The growth of intermediate inputs is a top contributor with an average contribution of 44.46%, followed by the planted area （18.16%）, investment in fixed assets （1.05%）, and labor input （-2.75%）, indicating that the contribution from the farmer’s input growth is mainly due to the growth of intermediate inputs and that the decline in labor inputs has become an obstacle for farmers in seeking grain output growth. Among the elements consisting of TFP growth, the contribution of technical progress is the largest （32.04%）, followed by grain subsidies （8.55%）, the average monthly temperature （4.26%）, the average monthly precipitation （-0.88%）, the adjusted scale effect （-5.66%）, and growth in technical efficiency （-21.01%）. In general, the contribution of climate factors and agricultural policy factor are positive and significant.
基金the results obtained from phases Ⅲ , Ⅳ, Ⅴ, and Ⅵ of the IRRI – Japan Collaborative Research Project, which was supported by the Ministry of Foreign Affairs and the Ministry of Agriculture, Forestry and Fisheries of Japan
文摘To enhance the yield potential of an elite indica rice cultivar,an introgression(BC_3-derived) line of IR64,YTH288,was developed using a new-plant-type cultivar,IR66215-44-2-3,as a donor parent.YTH288 has agronomically valuable characteristics such as large panicles,few unproductive tillers,and large leaves inherited from NPT.To identify the genetic basis of these traits,we used 167 F_2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits:days to heading(DTH),culm length(CL),flag leaf length(FLL),flag leaf width(FLW),and filled spikelet number per panicle(FSN).Six putative QTL were detected:four on chromosome4(for CL,FLL,FLW,and FSN) and two on chromosome 2(for DTH and FLL).All QTL with the IR66215-44-2-3 allele,except that for FLL on chromosome 2,had positive effects on each trait.To confirm the effects of these putative QTL,we developed NILs with the IR64 genetic background by marker-assisted selection.We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes2 and 4.Additionally,four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropic To enhance the yield potential of an elite indica rice cultivar, an introgression(BC3-derived) line of IR64, YTH288, was developed using a new-plant-type cultivar,IR66215-44-2-3, as a donor parent. YTH288 has agronomically valuable characteristics such as large panicles, few unproductive tillers, and large leaves inherited from NPT.To identify the genetic basis of these traits, we used 167 F2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits: days to heading(DTH), culm length(CL), flag leaf length(FLL), flag leaf width(FLW), and filled spikelet number per panicle(FSN). Six putative QTL were detected: four on chromosome4(for CL, FLL, FLW, and FSN) and two on chromosome 2(for DTH and FLL). All QTL with the IR66215-44-2-3 allele, except that for FLL on chromosome 2, had positive effects on each trait. To confirm the effects of these putative QTL, we developed NILs with the IR64 genetic background by marker-assisted selection. We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes2 and 4. Additionally, four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropiceffects for unique agronomic traits. These NILs can be used as research materials for studying each trait and as breeding materials for yield improvement of indica rice cultivars.
基金financially supported by the Japan International Research Center for Agricultural Sciences International Rice Research Institute (JIRCAS-IRRI) collaborative breeding projecta grant from the Institute of Crop Science, NARO, Japan
文摘Increasing rice yield potential is a continuous challenge posed by world population growth.To increase yield potential,favorable alleles of valuable genes need to be accumulated in promising germplasm.We conducted comparative yield trials for two years in Tsukuba,Japan,in a temperate region and at the International Rice Research Institute(IRRI),Philippines,in a tropical region using five high-yielding rice cultivars:Takanari and Hokuriku193,developed in Japan,and IR64,NSIC Rc158,and YTH183,developed in the Philippines.Genotype plus genotype×environment interaction(GGE)biplot analysis across four environments(two regions×two seasons)classified the five cultivars into four categories:Takanari and YTH183 showed high adaptability to both tropical and temperate regions,Hokuriku193 was suitable for temperate regions,NSIC Rc158 was suitable for the tropics,and IR64 was inferior to the other cultivars in both regions.The high yield and adaptability in Takanari and YTH183 were attributed to their large sink capacity with good grain filling.The plant type for high yield was different,however,between the two cultivars;Takanari was a panicle-weight type,whereas YTH183 was a panicle-number type.Evaluations of F2 progeny of a cross between Takanari and YTH183 showed transgressive segregation for number of panicles per plant as well as number of spikelets per panicle,leading some F2 plants to produce more spikelets per plant(corresponding to larger sink size)than the parental cultivars in both regions.These results suggest the possibility of developing rice cultivars with high yield potential in both temperate and tropical regions by crossing temperate with tropical high-yielding cultivars.
文摘Phospho compost application is important with respect to soil fertility and plant nutrition. Therefore, the objective was to evaluate the influence of phospho compost application on P availability and uptake by maize in red soil. The phosphorus applied in the form of phospho compost, as compare to rock phosphate and super phosphate at a rate of 50 and 100 mg P2O5 Kg-1 soil. The application was done as spot and mix application. Results indicate that, spot application of 100 mg P2O5 kg-1 soil as phospho compost (b) registered significantly higher P uptake (2.1 and 5.31 mg·pot-1) and available soil P (19.1 and 21.0 mg·kg-1) as compare to Rock Phosphate alone (0.60 and 0.97 mg·pot-1) and (5.6 and 6.0 mg·kg-1) at 30 and 60 day after sowing, respectively. The probable chelating effect from phospho composting increased the phosphorus use efficiency and resulted into higher relative agronomic efficiency in phospho compost (b) spot application (40%) over mix application (15%). The dry matter yield had positive and significant correlation with available P in soil and P uptake by maize plants at 30 and 60 day after sowing. Results concluded that phospho compost enriched with FYM was most effective in increasing phosphorus availability in red soil and increasing dry matter yield of maize plants.
基金JIRCAS International Collaborative Project Fund(B33102-331)Grant Project of Zhejiang Province for International Collaboration(2002AA217111)supported this work
文摘Field performance of whitebacked planthopper （WBPH）-resistance of four phenotypes was evaluated in Chunjiang 06 （C J-06） / TN1 DH rice lines, which were expressed by different combinations of sucking inhibitory and ovicidal traits inherited independently from C J-06. WBPH established the highest populations in susceptible DH lines that had neither sucking inhibitorynor ovicidal resistance. Both immigration and subsequent population levels were kept below the damage-causing density in the sucking inhibitory DH lines even under a WBPH outbreak. WBPH could not build up populations in the DH lines having both the sucking inhibitory and ovicidal resistance. Although WBPH immigrated preferentially to non-sucking inhibitory DH lines with ovicidal resistance, subsequent population buildup was significantly suppressed. It was concluded that the differential performance to WBPH-resistance in CJ-06 / TN1 DH lines was primarily due to the sucking inhibitory trait, and complementarity to the ovicidal trait.
文摘Teak (Tectona grandis L.) plantation management is said to be profitable, but small-scale farmers with teak plantations need to find appropriate and effective choices for plantation management because of their small plots. There have been few studies on how combinations of site quality, rotation and plant spacing affect financial evaluations of teak plantation management quantitatively. In this study, we introduced the yield table for teak plantations in Northeast Thailand, and investigated the effects of site quality with rotation (15-year and 20-year) and spacing (2 m × 4 m and 4 m × 4 m) on the financial evaluation of teak plantation management using discounted cash flow analysis. The equivalent annual incomes (EAI) and benefit/cost ratios (BCR) were negative and <1, respectively, at site indexes (SI) of 14 and 18, but increased ~2 - 3 times as SI rose from 22 (site of medium quality) to 26 and 26 to 30. The 20-year rotation was generally preferable to the 15-year one, especially at SI 22. At SI 30, 2 m × 4 m was more profitable than 4 m × 4 m for both rotations, but at SI 22, 20-year rotation with 4 m × 4 m was the most profitable, followed by 20-year with 2 m × 4 m.
文摘The original online version of this article (Noda, I. et al. (2014). Effects of Silvicultural Alternatives on Model-Based Financial Evaluation of Teak (Tectona grandis L.) Farm Forestry Management for Small-Scale Farmers in Northeast Thailand. Open Journal of Forestry, 4, 558-569. http://dx.doi.org/10.4236/ojf.2014.45060) was published in October. The author wishes to correct Table 5.
文摘Substantial potential exists to expand supplies of biomass for energy applications through more systematic collection of agricultural residues, more intensive cultivation of croplands, and reduced waste and losses in the food chain. This study aims to show how the potential can be calculated from public information sources, to put the potential in the context of global needs for liquid transport fuels, and to suggest some practical policy options for bringing part of the potential to market. It finds that if the theoretical potential is fully realized, enough liquid biofuel could be produced to displace the equivalent of all current global liquid fuel use for transport.
文摘Physiological responses were studied in temperature-controlled glass house at Okinawa, Japan to evaluate drought and high temperature resistances of cowpea cultivar/strains for Sahel, Africa. Four drought-tolerant cowpea cultivar/strains （cv. TVu-11986; TVu-11979; IT-96D-604 and Dan Ilia）, and three sensible strains （cv. IT96K-238-3, IT96K-231-1 and TVu-7778） were grown in pots and imposed to drought （soil content; 9.7±1.9%（w/w））, high （30/26℃, day/night, 12/12 hour）, normal （27/23℃, control） and low （24/20℃） temperature conditions after flowering. Plant fresh weight reduced 80%, 26% and 1% by dry, high and low temperature, respectively. Stem diameter decreased 32% and 2% by dry and low temperature, respectively, but increased 5% by high temperature. Difference between the drought tolerant and sensible cultivars/strains, pre-evaluated by IITA, was explained by relationship between stem diameter and plant fresh weight with 77% of reliability. The 35% of misclassification were due to misjudgment of drought tolerant as sensible in dry plot. The stem diameter highly correlated with all parts of plant weight in all regimes except in dry treatment. Difference of the classification between IITA and our results may cause different survival strategy against drought. The cultivars/strains, evaluated as drought tolerant by IITA, might fatten up at early stage, and could avoid from drought at latter growing stage.
基金supported by the National Natural Science Foundation of China[32070028 and 32370035 to Y.-J.L.,32070125 to Y.F.,and 32170051 to Q.C.]the National Key Research and Development Program of China[2021YFC2103600 to Y.-J.L.and 2023YFC3402304 to Y.F.]+2 种基金the International Partnership Program of Chinese Academy of Sciences[323GJHZ2022004MI to Y.-J.L.and A.K.]Shandong Energy Institute[SEI I202142 to Y.-J.L.,SEI S202106 to Q.C.,SEI I202106 to Y.F.]QIBEBT[Grant No.QIBEBT ICP2023046 to Y.F.].E.A.B.is the incumbent of The Maynard I.and Elaine Wishner Chair of Bio-organic Chemistry.
文摘The bioconversion of lignocellulose has attracted global attention,due to the significant potential of agricultural and forestry wastes as renewable zero-carbon resources and the urgent need for substituting fossil carbon.The cellulosome system is a multi-enzyme complex produced by anaerobic bacteria,which comprises cellulases,hemicellulases,and associated enzymatic and non-enzymatic components that promote biomass conversion.To enhance their efficiency in degrading recalcitrant lignocellulosic matrices,cellulosomes have been employed to construct biocatalysts for lignocellulose bioconversion,such as consolidated bioprocessing and consolidated bio-saccharification.Hemicelluloses,the second most abundant polysaccharides in plant cell walls,hold valuable application potential but can also induce inhibitory effects on cellulose hydrolysis,thus highlighting the indispensable roles of hemicellulases within the cellulosome complex.This review evaluated current research on cellulosomal hemicellulases,comparing their types,abundance,and regulation,primarily focusing on eight known cellulosome-producing species of different origins.We also reviewed their growth conditions,their hemicellulose-degrading capabilities,and the inhibitory effects of hemicellulose on cellulosome-based lignocellulose saccharification.Finally,we proposed strategies for targeted enhancement of hemicellulase in cellulosomes to improve lignocellulose bioconversion in future studies.
基金Supported by Project of Knowledge Innovation Engineeringof Chinese Academyof Sciences(No.KZCX3-SW-444)creativeitemplan of graduate student of Northwest Sci-Tech University of Agriculture and Forestry(No.05YCH023).
文摘cDNA libraries were constructed from the leaves of a rice (Oryza sativa L.) salt tolerancevariety Tesan抋i 2 growing in solutions with 150 mmol/L NaCl for 3 h or without salt stress. Three salt-responsive cDNA clones, Ts1, Ts2 and Ts3 were isolated by differential screening. Northern blottinganalysis showed that the transcription levels of Ts1 and Ts2 increased within 3 h salt stress and kept onincreasing within 24 h, while the transcription level of Ts3 reached its peak within 3 h. Sequence analysisindicated that there were no homologies between the three cDNA clones and any known gene. The threecDNA clones were mapped using a doubled haploid (DH) population derived from an indica variety ZYQ8,which was a salt tolerance parent of Tesan抋i 2, with a japonica variety JX17. Ts1, Ts2 and Ts3 werelocated on chromosomes 1, 3 and 7, respectively. It was noted that Ts1, Ts2, and Ts3 were in or near theregions of major or minor salt tolerance quantitative trait loci (QTLs), which were mapped in the same DHpopulation in a parallel study.
