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Romeo M Visperas - One of the best experts on this subject based on the ideXlab platform.
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synergic effect of flooding and nitrogen application on alleviation of soil sickness caused by aerobic rice monocropping
Plant Production Science, 2012Co-Authors: Lixiao Nie, B A M Bouman, Shaobing Peng, Farooq Shah, Jianliang Huang, Kehui Cui, Jing Xiang, Romeo M VisperasAbstract:The “aerobic rice” system is the cultivation of high yielding rice cultivars under non-Flooded Conditions in non-puddled (aerobic) soil with supplemental irrigation. The major constraint in wide ad...
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crop performance nitrogen and water use in Flooded and aerobic rice
Plant and Soil, 2005Co-Authors: P Belder, A R Castaneda, J.h.j. Spiertz, B A M Bouman, Shaobing Peng, Romeo M VisperasAbstract:Abstract Irrigated aerobic rice is a new system being developed for lowland areas with water shortage and for favorable upland areas with access to supplementary irrigation. It entails the cultivation of nutrient-responsive cultivars in nonsaturated soil with sufficient external inputs to reach yields of 70–80% of high-input Flooded rice. To obtain insights into crop performance, water use, and N use of aerobic rice, a field experiment was conducted in the dry seasons of 2002 and 2003 in the Philippines. Cultivar Apo was grown under Flooded and aerobic Conditions at 0 and at 150 kg fertilizer N ha–1. The aerobic fields were flush irrigated when the soil water potential at 15-cm depth reached –30 kPa. A 15N isotope study was carried out in microplots within the 150-N plots to determine the fate of applied N. The yield under aerobic Conditions with 150 kg N ha–1 was 6.3 t ha–1 in 2002 and 4.2 t ha–1 in 2003, and the irrigation water input was 778 mm in 2002 and 826 mm in 2003. Compared with Flooded Conditions, the yield was 15 and 39% lower, and the irrigation water use 36 and 41% lower in aerobic plots in 2002 and 2003, respectively. N content at 150 kg N ha–1 in leaves and total plant was nearly the same for aerobic and Flooded Conditions, indicating that crop growth under aerobic Conditions was limited by water deficit and not by N deficit. Under aerobic Conditions, average fertilizer N recovery was 22% in both the main field and the microplot, whereas under Flooded Conditions, it was 49% in the main field and 36% in the microplot. Under both Flooded and aerobic Conditions, the fraction of 15N that was determined in the soil after the growing season was 23%. Since nitrate contents in leachate water were negligible, we hypothesized that the N unaccounted for were gaseous losses. The N unaccounted for was higher under aerobic Conditions than under Flooded Conditions. For aerobic rice, trials are suggested for optimizing dose and timing of N fertilizer. Also further improvements in water regime should be made to reduce crop water stress.
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yield and water use of irrigated tropical aerobic rice systems
Agricultural Water Management, 2005Co-Authors: B A M Bouman, A R Castaneda, Shaobing Peng, Romeo M VisperasAbstract:Abstract Increasing water scarcity necessitates the development of irrigated rice systems that require less water than traditional Flooded rice. In irrigated aerobic rice systems, rice grows in nonFlooded and nonsaturated soil under supplemental irrigation. The development of such systems should start with the identification of promising varieties and the quantification of yield potential, water use, field water outflows, and water productivity. In this paper, we report on the results of growing different tropical upland and lowland rice varieties under irrigated aerobic Conditions during six seasons in 2001–2003 at the International Rice Research Institute in the Philippines. The highest yields under aerobic Conditions were realized in the dry season with the improved upland variety Apo (5.7 t ha−1) and the lowland hybrid rice Magat (6 t ha−1). These high yields were obtained in relatively wet soil with seasonal-average soil moisture tensions in the root zone of 10–12 kPa and with maximum values of around 40 kPa. On average, the mean yield of all varieties was 32% lower under aerobic Conditions than under Flooded Conditions in the dry season and 22% lower in the wet season. Total water input was 1240–1880 mm in Flooded fields and 790–1430 mm in aerobic fields. On average, aerobic fields used 190 mm less water in land preparation, and had 250–300 mm less seepage and percolation, 80 mm less evaporation, and 25 mm less transpiration than Flooded fields. Without plastic sheets to prevent seepage in Flooded fields, the water productivity of rice (with respect to rainfall and irrigation water input) under aerobic Conditions was 32–88% higher than under Flooded Conditions. We conclude that the concept of aerobic rice holds promise for farmers that do not have access to enough water to grow Flooded lowland rice. More research is needed into the development of improved varieties, the optimization of crop and water management, and the sustainability of aerobic rice under continuous cropping.
B A M Bouman - One of the best experts on this subject based on the ideXlab platform.
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synergic effect of flooding and nitrogen application on alleviation of soil sickness caused by aerobic rice monocropping
Plant Production Science, 2012Co-Authors: Lixiao Nie, B A M Bouman, Shaobing Peng, Farooq Shah, Jianliang Huang, Kehui Cui, Jing Xiang, Romeo M VisperasAbstract:The “aerobic rice” system is the cultivation of high yielding rice cultivars under non-Flooded Conditions in non-puddled (aerobic) soil with supplemental irrigation. The major constraint in wide ad...
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performance of aerobic rice varieties under irrigated Conditions in north china
Field Crops Research, 2006Co-Authors: B A M Bouman, Xiaoguang Yang, Huaqi Wang, Zhimin Wang, Junfang Zhao, Bin ChenAbstract:Abstract In Northern China, high-yielding aerobic rice varieties are released to farmers to grow rice as a supplementary-irrigated upland crop to cope with water scarcity. If the key factors contributing to the high yield of these varieties are understood, rapid advancements can be made in developing aerobic rice varieties for water-scarce environments in other parts of Asia. In 2001–2002, we conducted experiments with aerobic varieties HD502 and HD297 and lowland variety JD305 under aerobic and Flooded Conditions. Five irrigation treatments were implemented in aerobic soil to create different soil moisture regimes. Under Flooded Conditions, all three varieties had comparable radiation use (RUE) efficiencies of 2.09–2.26 g dry matter (DM) MJ−1 in 2001 and 2.40–2.53 g DM MJ−1 in 2002, and harvest indices (HI) of 0.38–0.40 in both years. Differences in yield among the varieties are explained by differences in growth duration. Under aerobic Conditions, mean RUE over water treatments dropped to 1.70–1.72 g DM MJ−1 for all three varieties in 2001, and to 1.62 for HD502, 1.71 for HD297 and 1.86 for JD305 in 2002. With increasing dryness of the soil, the amount of intercepted light decreased at about the same rate for all varieties, but RUE decreased faster in the lowland than in the two aerobic varieties. The HI of JD305 decreased dramatically with increasing soil dryness and reached values of 0.19–0.21 in 2002. In contrast, the HI of both aerobic varieties remained relatively high under aerobic Conditions, with lowest values of 0.27–0.28 for HD297 and 0.34–0.35 for HD502 in 2002. The relatively high HI of the aerobic varieties compensated for their relatively short growth duration so that their yields were higher than that of JD305 in all treatments. A high percentage filled grains is a key factor contributing to the high HI of the aerobic varieties under aerobic Conditions.
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crop performance nitrogen and water use in Flooded and aerobic rice
Plant and Soil, 2005Co-Authors: P Belder, A R Castaneda, J.h.j. Spiertz, B A M Bouman, Shaobing Peng, Romeo M VisperasAbstract:Abstract Irrigated aerobic rice is a new system being developed for lowland areas with water shortage and for favorable upland areas with access to supplementary irrigation. It entails the cultivation of nutrient-responsive cultivars in nonsaturated soil with sufficient external inputs to reach yields of 70–80% of high-input Flooded rice. To obtain insights into crop performance, water use, and N use of aerobic rice, a field experiment was conducted in the dry seasons of 2002 and 2003 in the Philippines. Cultivar Apo was grown under Flooded and aerobic Conditions at 0 and at 150 kg fertilizer N ha–1. The aerobic fields were flush irrigated when the soil water potential at 15-cm depth reached –30 kPa. A 15N isotope study was carried out in microplots within the 150-N plots to determine the fate of applied N. The yield under aerobic Conditions with 150 kg N ha–1 was 6.3 t ha–1 in 2002 and 4.2 t ha–1 in 2003, and the irrigation water input was 778 mm in 2002 and 826 mm in 2003. Compared with Flooded Conditions, the yield was 15 and 39% lower, and the irrigation water use 36 and 41% lower in aerobic plots in 2002 and 2003, respectively. N content at 150 kg N ha–1 in leaves and total plant was nearly the same for aerobic and Flooded Conditions, indicating that crop growth under aerobic Conditions was limited by water deficit and not by N deficit. Under aerobic Conditions, average fertilizer N recovery was 22% in both the main field and the microplot, whereas under Flooded Conditions, it was 49% in the main field and 36% in the microplot. Under both Flooded and aerobic Conditions, the fraction of 15N that was determined in the soil after the growing season was 23%. Since nitrate contents in leachate water were negligible, we hypothesized that the N unaccounted for were gaseous losses. The N unaccounted for was higher under aerobic Conditions than under Flooded Conditions. For aerobic rice, trials are suggested for optimizing dose and timing of N fertilizer. Also further improvements in water regime should be made to reduce crop water stress.
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yield and water use of irrigated tropical aerobic rice systems
Agricultural Water Management, 2005Co-Authors: B A M Bouman, A R Castaneda, Shaobing Peng, Romeo M VisperasAbstract:Abstract Increasing water scarcity necessitates the development of irrigated rice systems that require less water than traditional Flooded rice. In irrigated aerobic rice systems, rice grows in nonFlooded and nonsaturated soil under supplemental irrigation. The development of such systems should start with the identification of promising varieties and the quantification of yield potential, water use, field water outflows, and water productivity. In this paper, we report on the results of growing different tropical upland and lowland rice varieties under irrigated aerobic Conditions during six seasons in 2001–2003 at the International Rice Research Institute in the Philippines. The highest yields under aerobic Conditions were realized in the dry season with the improved upland variety Apo (5.7 t ha−1) and the lowland hybrid rice Magat (6 t ha−1). These high yields were obtained in relatively wet soil with seasonal-average soil moisture tensions in the root zone of 10–12 kPa and with maximum values of around 40 kPa. On average, the mean yield of all varieties was 32% lower under aerobic Conditions than under Flooded Conditions in the dry season and 22% lower in the wet season. Total water input was 1240–1880 mm in Flooded fields and 790–1430 mm in aerobic fields. On average, aerobic fields used 190 mm less water in land preparation, and had 250–300 mm less seepage and percolation, 80 mm less evaporation, and 25 mm less transpiration than Flooded fields. Without plastic sheets to prevent seepage in Flooded fields, the water productivity of rice (with respect to rainfall and irrigation water input) under aerobic Conditions was 32–88% higher than under Flooded Conditions. We conclude that the concept of aerobic rice holds promise for farmers that do not have access to enough water to grow Flooded lowland rice. More research is needed into the development of improved varieties, the optimization of crop and water management, and the sustainability of aerobic rice under continuous cropping.
Satoshi Shimamura - One of the best experts on this subject based on the ideXlab platform.
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secondary aerenchyma formation and root growth response of soybean glycine max seedlings under Flooded Conditions
Improving food energy and environment with better crops. 7th Asian Crop Science Association Conference IPB International Convention Center Bogor Indon, 2013Co-Authors: Toshihiro Mochizuki, Satomi Sakazono, Sayuri Kajihara, Satoshi ShimamuraAbstract:Most of wetland species can develop their roots into Flooded soils because of the presence of longitudinal aerenchyma channels that facilitates oxygen diffusion from shoot to root tips. This tissue is called as primary aerenchyma because it is formed in fundamental tissues. It is also formed in rice root, consequently rice plants can grow well in paddy field. On the other hand, it is considered that most of mesophytes such as field crops cannot grow under Flooded and excess moisture Conditions because of their low ability to develop aerenchyma. However, we found that soybean plants could develop aerenchyma and grow well in flooding compared with other leguminous crops such as Vigna and Phaseolus species. This type of aerenchyma, which is consisted of white spongy tissue filled with gas space and is differentiated from secondary meristem (phellogen), is called assecondary aerenchyma. It plays a role in supplying oxygen from the aerial parts to the Flooded roots and nodules. In our recent study, it was observed that there was a wide range of varietal differences on secondary aerenchyma formation and adventitious root development in soybean seedlings under flooding. Although the research for secondary aerenchyma in soybean plants is on the way, it may be able to breed soybean varieties with flooding tolerance.
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formation and function of secondary aerenchyma in hypocotyl roots and nodules of soybean glycine max under Flooded Conditions
Plant and Soil, 2003Co-Authors: Satoshi Shimamura, Toshihiro Mochizuki, Youichi Nada, Masataka FukuyamaAbstract:Flooding is a major problem in many areas of the world and soybean is susceptible to the stress. Understanding the morphological mechanisms of flooding tolerance is important for developing flood-tolerant genotypes. We investigated secondary aerenchyma formation and function in soybean (Glycine max) seedlings grown under Flooded Conditions. Secondary aerenchyma, a white and spongy tissue, was formed in the hypocotyl, tap root, adventitious roots and root nodules after 3 weeks of flooding. Under irrigated Conditions aerenchyma development was either absent or rare and phellem was formed in the hypocotyl, tap root, adventitious roots and root nodules. Secondary meristem partially appeared at the outer parts of the interfascicular cambium and girdled the stele, and then cells differentiated to construct secondary aerenchyma in the Flooded hypocotyl. These morphological changes proceeded for 4 days after the initiation of the flooding. After 14 days of treatment, porosity exceeded 30% in Flooded hypocotyl with well-developed secondary aerenchyma, while it was below 10% in hypocotyl of irrigated plants that had no aerenchyma. When Vaseline was applied to the hypocotyl of plants from a Flooded treatment to prevent the entry of atmospheric oxygen into secondary aerenchyma, plant growth, especially that of roots, was sharply inhibited. Thus secondary aerenchyma might be an adaptive response to flooding.
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secondary aerenchyma formation growth and yield of soybean plants grown under continuously Flooded Conditions
Japanese Journal of Crop Science, 2003Co-Authors: Satoshi Shimamura, Toshihiro Mochizuki, Youichi Nada, Masataka FukuyamaAbstract:湛水田におけるダイズ栽培の可能性について検討するため, 二次通気組織が良く発達するダイズ品種アソアオガリを用い, 湛水条件下における二次通気組織の形成経過, 乾物重の推移および子実収量を調査した. ポット栽培および圃場栽培実験を行い, 初生葉展開期から必要に応じて潅水する潅水条件 (対照区) と水位を土壌表面上約3cmに保つ湛水条件 (湛水区) で栽培した. 両実験において, 湛水区のダイズは枯死することなく収穫まで至った. 対照区では, 二次通気組織は胚軸, 主根, 不定根および根粒のいずれにもほとんど形成されなかったが, 湛水区では, 生育初期から形成が認められ, 形成量は生育に伴って増加した. また, 胚軸の空隙率は生育期間を通じて対照区に比べて高かった. ポット栽培の湛水区では, 植物体は小型化し, 子実収量も減少したが, 圃場栽培では, 密植により, 対照区と同程度の面積当たり稔実莢数や稔実粒数が得られ, 子実収量は300g/m2以上であった. 以上の結果から, 本品種は湛水条件下では二次通気組織を速やかに形成し, これを生育後期まで維持することによって, 常時湛水条件下においても生育を全うしたものと推察され, 湛水田におけるダイズ栽培の可能性が示唆された.
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secondary aerenchyma formation and its relation to nitrogen fixation in root nodules of soybean plants glycine max grown under Flooded Conditions
Plant Production Science, 2002Co-Authors: Satoshi Shimamura, Toshihiro Mochizuki, Youichi Nada, Masataka FukuyamaAbstract:Soybean (Glycine max (L.) Merr.) is considered to be susceptible to flooding, a major agronomic problem in the world, and nitrogenase activity rapidly declines due to oxygen deficiency in root nodu...
Masataka Fukuyama - One of the best experts on this subject based on the ideXlab platform.
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formation and function of secondary aerenchyma in hypocotyl roots and nodules of soybean glycine max under Flooded Conditions
Plant and Soil, 2003Co-Authors: Satoshi Shimamura, Toshihiro Mochizuki, Youichi Nada, Masataka FukuyamaAbstract:Flooding is a major problem in many areas of the world and soybean is susceptible to the stress. Understanding the morphological mechanisms of flooding tolerance is important for developing flood-tolerant genotypes. We investigated secondary aerenchyma formation and function in soybean (Glycine max) seedlings grown under Flooded Conditions. Secondary aerenchyma, a white and spongy tissue, was formed in the hypocotyl, tap root, adventitious roots and root nodules after 3 weeks of flooding. Under irrigated Conditions aerenchyma development was either absent or rare and phellem was formed in the hypocotyl, tap root, adventitious roots and root nodules. Secondary meristem partially appeared at the outer parts of the interfascicular cambium and girdled the stele, and then cells differentiated to construct secondary aerenchyma in the Flooded hypocotyl. These morphological changes proceeded for 4 days after the initiation of the flooding. After 14 days of treatment, porosity exceeded 30% in Flooded hypocotyl with well-developed secondary aerenchyma, while it was below 10% in hypocotyl of irrigated plants that had no aerenchyma. When Vaseline was applied to the hypocotyl of plants from a Flooded treatment to prevent the entry of atmospheric oxygen into secondary aerenchyma, plant growth, especially that of roots, was sharply inhibited. Thus secondary aerenchyma might be an adaptive response to flooding.
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secondary aerenchyma formation growth and yield of soybean plants grown under continuously Flooded Conditions
Japanese Journal of Crop Science, 2003Co-Authors: Satoshi Shimamura, Toshihiro Mochizuki, Youichi Nada, Masataka FukuyamaAbstract:湛水田におけるダイズ栽培の可能性について検討するため, 二次通気組織が良く発達するダイズ品種アソアオガリを用い, 湛水条件下における二次通気組織の形成経過, 乾物重の推移および子実収量を調査した. ポット栽培および圃場栽培実験を行い, 初生葉展開期から必要に応じて潅水する潅水条件 (対照区) と水位を土壌表面上約3cmに保つ湛水条件 (湛水区) で栽培した. 両実験において, 湛水区のダイズは枯死することなく収穫まで至った. 対照区では, 二次通気組織は胚軸, 主根, 不定根および根粒のいずれにもほとんど形成されなかったが, 湛水区では, 生育初期から形成が認められ, 形成量は生育に伴って増加した. また, 胚軸の空隙率は生育期間を通じて対照区に比べて高かった. ポット栽培の湛水区では, 植物体は小型化し, 子実収量も減少したが, 圃場栽培では, 密植により, 対照区と同程度の面積当たり稔実莢数や稔実粒数が得られ, 子実収量は300g/m2以上であった. 以上の結果から, 本品種は湛水条件下では二次通気組織を速やかに形成し, これを生育後期まで維持することによって, 常時湛水条件下においても生育を全うしたものと推察され, 湛水田におけるダイズ栽培の可能性が示唆された.
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secondary aerenchyma formation and its relation to nitrogen fixation in root nodules of soybean plants glycine max grown under Flooded Conditions
Plant Production Science, 2002Co-Authors: Satoshi Shimamura, Toshihiro Mochizuki, Youichi Nada, Masataka FukuyamaAbstract:Soybean (Glycine max (L.) Merr.) is considered to be susceptible to flooding, a major agronomic problem in the world, and nitrogenase activity rapidly declines due to oxygen deficiency in root nodu...
Midori Okami - One of the best experts on this subject based on the ideXlab platform.
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root growth dynamics and stomatal behaviour of rice oryza sativa l grown under aerobic and Flooded Conditions
Field Crops Research, 2010Co-Authors: Yoichiro Kato, Midori OkamiAbstract:Abstract Aerobic rice culture is a new technology designed to reduce water use, but the vulnerability of rice to aerobic condition has limited its development. The objective of this study was to characterize the root growth and stomatal behaviour of four rice cultivars grown in Flooded and aerobic culture for 2 years. In aerobic culture, where the soil water potential at 20-cm depth averaged between −15 and −30 kPa, total root biomass was significantly lower than in Flooded culture for the whole growth period, owing to a reduction in root biomass in the surface layer. Dry-matter partitioning to roots decreased, but the ratio of deep root biomass to total root biomass tended to be higher in aerobic culture than in Flooded culture. The low root-to-shoot ratio and poor root growth in the surface layer in aerobic culture are attributable to the considerable reduction in adventitious root number. As a result, the varietal difference in total root biomass was due largely to individual root growth in aerobic culture. Stomatal closure was distinct at the vegetative stage in aerobic culture, even when the soil water potential was near field capacity, partly because of the poor rooting vigour. When the soil water potential at 20-cm depth was below −50 kPa, the stomatal behaviour reflected the root growth in the subsurface layer. These results suggest the role of vigorous root growth in soil water uptake and hence, in maintaining transpiration in aerobic rice culture.