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Yoichiro Kato - One of the best experts on this subject based on the ideXlab platform.
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on farm assessment of a new early maturing drought tolerant rice cultivar for dry Direct Seeding in rainfed lowlands
Field Crops Research, 2018Co-Authors: Hoshie Ohno, Nino P M C Banayo, Crisanta Sunio Bueno, Junichi Kashiwagi, Taiken Nakashima, Kazuto Iwama, Aurora M Corales, Ricardo Garcia, Yoichiro KatoAbstract:Abstract Dry Direct Seeding of rice (DDSR) is becoming a common practice in drought-prone lowland areas where there is insufficient labor for transplanting, but early-season drought often causes poor crop establishment, which allows subsequent weed infestation. Although early-maturing drought-tolerant cultivars have been released in tropical Asia in the last decade, almost all farmers in these areas still use cultivars selected for irrigated lowlands. The objective of our study was to compare a new drought-tolerant cultivar (Rc348) and a popular cultivar of farmers (Rc10) in DDSR under rainfed lowland conditions. On-farm experiments in three villages in northern Luzon, the Philippines, showed that the yield of Rc10, but not Rc348, was negatively associated with soil drying. Although their average yields were comparable (Rc348, 3.03 t ha−1; Rc10, 3.00 t ha−1), Rc348 yielded 34% more with moderate to severe weed infestation or soil dryness (3.12 vs. 2.33 t ha−1). Weed infestation increased with increasing soil dryness, but the weed pressure was more severe for Rc10 than for Rc348. Rc348 had a higher seedling emergence percentage, number of seedlings m−2, and ground cover at 30 days after sowing than Rc10 in drought-prone fields at upper (drier) positions in the toposequence. These results were validated by an on-station experiment with controlled drought stress at the International Rice Research Institute. We suggest that the adoption of newly released cultivars from the breeding programs for rainfed rice with reliable seedling emergence and early vigor in the presence of fluctuating soil moisture would stabilize the yield of DDSR in the target drought-prone areas.
Timothy C Paulitz - One of the best experts on this subject based on the ideXlab platform.
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root diseases of wheat and barley during the transition from conventional tillage to Direct Seeding
Plant Disease, 2006Co-Authors: Kurtis L Schroeder, Timothy C PaulitzAbstract:The use of Direct Seeding (no-till) in place of tillage can reduce soil erosion and improve water infiltration. However, despite these improvements in soil quality, growers in the Pacific Northwest are reluctant to adopt Direct Seeding, partially because of fears of increased root diseases caused by Gaeumannomyces graminis var. tritici, Rhizoctonia spp., and Pythium spp. To examine the effect of the transition from conventional tillage to Direct Seeding, field plots were established at two locations. One site had been managed with Direct Seeding for 12 years, and the second had been conventionally tilled. Over 4 years, a portion of each plot was tilled or Direct seeded, and planted to wheat or barley. Plants in the tilled plots had consistently more crown roots than plants in Direct-seeded plots. Rhizoctonia root rot and yield did not differ between tillage types during the first 2 years of the study. However, in the third and fourth years of the transition to Direct Seeding, a higher incidence of Rhizoctonia root rot, increased hyphal activity of R. solani, and reduced yields were observed in Direct-seeded plots. Populations of R. oryzae and Pythium spp., and incidence of take-all were the same for both management practices.
Takashi Wada - One of the best experts on this subject based on the ideXlab platform.
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decrease in density of the apple snail pomacea canaliculata lamarck gastropoda ampullariidae in paddy fields after crop rotation with soybean and its population growth during the crop season
Applied Entomology and Zoology, 2004Co-Authors: Takashi Wada, Katsuya Ichinose, Yoichi Yusa, Naoyuki SugiuraAbstract:We compared the densities of the apple snail, Pomacea canaliculata, between fields that had been planted with soybean or rice in the previous summer. The densities of overwintered snails soon after irrigation at the beginning of rice planting were all very low in the fields after soybean. These values were much lower than the control threshold for the apple snail in Direct Seeding. Therefore, crop rotation with soybean seems to be a good economic measure to control the apple snail in Direct Seeding. The snail populations increased very rapidly in both types of fields, in particular, after soybean. Within two and a half summer months, the snail densities in the fields after soybean reached almost the same level as those in the fields after rice. This rapid population recovery in fields after soybean seems to be caused by density-dependent growth and reproduction in this species.
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strategies for controlling the apple snail pomacea canaliculata lamarck gastropoda ampullariidae in japanese Direct sown paddy fields
Jarq-japan Agricultural Research Quarterly, 2004Co-Authors: Takashi WadaAbstract:The apple snail Pomacea canaliculata becomes a much more serious pest in Direct-sown rice fields than in transplanted fields. In south Japan, it represents an important constraint on the implementation of Direct Seeding. Described here are possible measures to control the snails and suggestions for its management in Japanese Direct-sown rice fields. Crop rotation with upland crops is a practical way with the lowest extra cost. The apple snails were often not eradicated by growing an upland crop in the previous summer. However, snail densities always decreased below the control threshold in Direct-sown fields (0.5 snails/m 2 ). Longer drainage period after sowing greatly reduced snail damage. Thus, draining fields for 10 to 20 days after sowing is a basic practice to control snails in Direct Seeding. Tillage and puddling have a function to crush snails and, thus, reduce snail densities. "Intensive tillage", in which a field with compacted hard soil is tilled shallow with faster cultivator rotation, achieved higher snail mortality. It is recommended to lower the risk of snail damage after unexpected heavy rain. An application of bait type metaldehyde showed enough control effects to avoid rice damage by snails even in heavy rain conditions. The stable effects seemed to be due to the active ingredient in the bait type which is dissolved slowly. Improving techniques for weeding and for draining fields effectively are necessary for better snail management in Direct Seeding.
Aymeric Ricome - One of the best experts on this subject based on the ideXlab platform.
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constraints to farmers adoption of Direct Seeding mulch based cropping systems a farm scale modeling approach applied to the mountainous slopes of vietnam
Agricultural Systems, 2010Co-Authors: Francois Affholder, Damien Jourdain, Dang Dinh Quang, To Phuc Tuong, Marion Morize, Aymeric RicomeAbstract:Abstract Substantial initiatives are under way in the tropical world to develop and promote Direct-Seeding mulch-based cropping systems (DMC) in order to reduce soil erosion and improve crop nutrient and water balances. DMC have been adopted by large-scale mechanized farmers, especially in America and Australia, but seldom by resource-poor farmers in the developing world. This study was conducted in Vietnam with the aim of evaluating the feasibility of farmers’ implementing DMC in a mountainous area. The method involved simulation of rational households maximizing their income subject to food security constraints and availability of resources. It generated insight into why farmers of a small region were reluctant to adopt DMC due to the extra labor and input required to implement these techniques during the first years, which hampers their economic performance. In another region, under different biophysical and economic environmental conditions, the study showed that DMC were more likely to be adopted provided that possible constraints at the community level are overcome. The method also allowed us to discuss the types of technical improvements that would make DMC more attractive to farmers. For most farm types, labor required by mulch establishment would have to be reduced by more than 30%. This would mean spreading much less biomass than the 7 t ha −1 currently necessary, compromising the weed-control function of mulch. This would be technically feasible only by using herbicides but this would not be economically sound since it would increase cash requirements. The study showed that subsidies of 50 to more than 200 USD ha −1 were necessary to enable the conversion of all conventionally managed sloping land into DMC in the simulations. These amounts are high relatively to gross margins (250–750 USD ha −1 ) under conventional management.
Satoshi Yoshinaga - One of the best experts on this subject based on the ideXlab platform.
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improved lodging resistance in rice oryza sativa l cultivated by submerged Direct Seeding using a newly developed hill seeder
Jarq-japan Agricultural Research Quarterly, 2005Co-Authors: Satoshi YoshinagaAbstract:Submerged Direct-seeded rice is more susceptible to lodging during the ripening period than is transplanted rice. Comparing different Seeding methods of Direct Seeding cultivation, lodging resistance is considered to be highest in hill-seeded rice. However, practical hill-seeders did not exist, and previously Direct-Seeding had been conducted by broadcast- or row-Seeding. This paper discusses the development of a hill seeder and improvements in the lodging resistance of hill-seeded rice, both of which have contributed to the recent widespread cultivation of submerged, Direct-seeded rice in Japan. The newly developed hill-seeder effectively drives seeds intermittently into the puddled soil and enabled establishment of a hill which is composed of several plants as is a transplanted hill. Hill-seeded rice showed remarkable higher pushing resistance than broadcast-seeded rice across a range of seedling density and Seeding depth after heading, while the plant length was longer in hill-seeded rice. It is suggested that the high lodging resistance of the hill-seeded rice is derived from the larger number of panicles per hill, because the lodging resistance varied depending on the number of panicles in a hill. The area cultivated by hill-Seeding has been increasing since 1998, in 2004, it occupied 25% of the total submerged Direct-seeded area.
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improvement of lodging resistance in submerged Direct Seeding rice oryza sativa l cultivation using a newly developed shooting hill seeder effects of seedling density on the lodging resistance of hill seeded rice as compared with that of broadcast se
Japanese Journal of Crop Science, 2001Co-Authors: Satoshi Yoshinaga, Kenzo Wakimoto, Kohei Tasaka, Ken-ichi Matsushima, Tatsushi Togashi, Kunji ShimotsuboAbstract:The characteristics of lodging resistance in hill-seeded rice were compared with those in broadcast-seeded rice at three different plant densities (40, 80 and 160 plants m-2) to establish the submerged Direct Seeding rice cultivation using a newly developed 'Shooting hill-seeder'. In the hill-seeded rice, the culm was longer than in broadcast-seeded rice, applying a strong force to the basal part of the hill. However, they did not lodge easily because the percentage of productive tillers was high resulting in superior characteristics of the culm related to the lodging resistance, and they had extremely high pushing resistance. Such differences in the lodging resistance between hill-and broadcast-seeded rice plants were remarkable at a high plant density. In the broadcast-seeded rice, the number of panicles per hill is fewer than 10 when they are cultivated at a density higher than 40 plants m-2, and the lodging resistance decreased with decreasing number of panicles per hill. On the other hand, in the hill-seeded rice (40-160 plants m-2, 30cm inter-row and 20cm intra-row spacing), the number of panicles per hill is 20-25 even when the seedling density fluctuates within the range of 40-160 seedlings m-2 (2-10 seedlings per hill), and lodging resistance is stable. Because the fluctuation of seedling density is inevitable, the hill-Seeding cultivation with the above characteristics is favorable for the stabilization of submerged Direct Seeding cultivation.
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effects of drainage after submerged Direct Seeding on the effectiveness of fertilized nitrogen and the growth and yield of rice plants
Japanese Journal of Crop Science, 2000Co-Authors: Satoshi Yoshinaga, Kenzo Wakimoto, Kohei Tasaka, Ken-ichi Matsushima, Tatsushi Togashi, Mizuhiko Nishida, Kunji ShimotsuboAbstract:Drainage after Seeding has recently been practiced in general for the improvement of seedling emergence in submerged Direct-Seeding rice(Oryza sativa L.)cultivation. We examined the relationship between water management after Direct-Seeding and the effectiveness of fertilized nitrogen to clarify the effects of drainage on the growth and yield of rice. It was confirmed that the drainage after Seeding improved the seedling emergence rate and stimulated the initial growth of the seedling. When controlled release fertilizer(LPl00)was applied as basal dressing, water management after Seeding had no effect on the growth and yield. However, when ammonium sulfate was applied, the yield was reduced by the drainage after Seeding, due to the decrease in nitrogen uptake of rice at the panicle initiation stage, and resulting reduction in the number of spikelets. In this case, nitrogen uptake seemed to be reduced because nitrogen uptake in the early growth stage was increased by the increase in initial growth and tillering and because the content of ammonium nitrogen in soil was reduced by nitrification of the fertilized nitrogen during drainage. These results showed that the suppression of nitrogen uptake at the initial growth stage and the avoidance of nitrogen deficiency at the intermediate growth stage, are important to stabilize not only seedling emergence but also growth and yield for the management of drainage after Seeding.