食品加工への非穀物性カラフル作物の利用特性

博士（農学）岩手大

Response of 10 elite “green super rice” genotypes to weed infestation in aerobic rice systems

In recent years, water and labor shortage in Southeast Asia is driving the farmers towards dry-seeded rice systems. Weed infestation is a serious threat for adoption of these systems. A study was conducted in the wet and dry seasons to evaluate the performance of 10 elite “Green Super Rice” (a recently named group of rice genotypes bred for unfavorable marginal environments) genotypes at two different weed infestation levels (partial and moderate weed control) under dryseeded conditions. Average yield loss due to weed competition in the partial weed control treatment ranged from 12-57% in the wet season and 2-23% in the dry season. In the partial weed control plots, the drought pyramiding genotype IR83140-B-11-B performed well, resulting in 2850 and 4610 kg ha-1 of yield in the wet and dry seasons, respectively. The yield loss of this genotype in the partial weed control plots relative to the moderate weed control plots was only 21% in the wet season and 10% in the dry season. Results clearly showed that grain yield in different genotypes were positively correlated with leaf area at an early stage of the crop. The study also found negative and linear correlation between grain yield and weed biomass at harvest, demonstrating the importance of weeds in dry-seeded rice systems. The study suggested that genotypes with a larger leaf area could be integrated with other weed management strategies to achieve sustainable weed control in dry-seeded rice systems

Effects of vertical distribution of soil inorganic nitrogen on root growth and subsequent nitrogen uptake by field vegetable crops

Information is needed about root growth and N uptake of crops under different soil conditions to increase nitrogen use efficiency in horticultural production. The purpose of this study was to investigate if differences in vertical distribution of soil nitrogen (Ninorg) affected root growth and N uptake of a variety of horticultural crops. Two field experiments were performed each over 2 years with shallow or deep placement of soil Ninorg obtained by management of cover crops. Vegetable crops of leek, potato, Chinese cabbage, beetroot, summer squash and white cabbage reached root depths of 0.5, 0.7, 1.3, 1.9, 1.9 and more than 2.4 m, respectively, at harvest, and showed rates of root depth penetration from 0.2 to 1.5 mm day)1 C)1. Shallow placement of soil Ninorg resulted in greater N uptake in the shallow-rooted leek and potato. Deep placement of soil Ninorg resulted in greater rates of root depth penetration in the deep-rooted Chinese cabbage, summer squash and white cabbage, which increased their depth by 0.2–0.4 m. The root frequency was decreased in shallow soil layers (white cabbage) and increased in deep soil layers (Chinese cabbage, summer squash and white cabbage). The influence of vertical distribution of soil Ninorg on root distribution and capacity for depletion of soil Ninorg was much less than the effect of inherent differences between species. Thus, knowledge about differences in root growth between species should be used when designing crop rotations with high N use efficiency

Abatacept in individuals at high risk of rheumatoid arthritis (APIPPRA): a randomised, double-blind, multicentre, parallel, placebo-controlled, phase 2b clinical trial

\ua9 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Background: Individuals with serum antibodies to citrullinated protein antigens (ACPA), rheumatoid factor, and symptoms, such as inflammatory joint pain, are at high risk of developing rheumatoid arthritis. In the arthritis prevention in the pre-clinical phase of rheumatoid arthritis with abatacept (APIPPRA) trial, we aimed to evaluate the feasibility, efficacy, and acceptability of treating high risk individuals with the T-cell co-stimulation modulator abatacept. Methods: The APIPPRA study was a randomised, double-blind, multicentre, parallel, placebo-controlled, phase 2b clinical trial done in 28 hospital-based early arthritis clinics in the UK and three in the Netherlands. Participants (aged ≥18 years) at risk of rheumatoid arthritis positive for ACPA and rheumatoid factor with inflammatory joint pain were recruited. Exclusion criteria included previous episodes of clinical synovitis and previous use of corticosteroids or disease-modifying antirheumatic drugs. Participants were randomly assigned (1:1) using a computer-generated permuted block randomisation (block sizes of 2 and 4) stratified by sex, smoking, and country, to 125 mg abatacept subcutaneous injections weekly or placebo for 12 months, and then followed up for 12 months. Masking was achieved by providing four kits (identical in appearance and packaging) with pre-filled syringes with coded labels of abatacept or placebo every 3 months. The primary endpoint was the time to development of clinical synovitis in three or more joints or rheumatoid arthritis according to American College of Rheumatology and European Alliance of Associations for Rheumatology 2010 criteria, whichever was met first. Synovitis was confirmed by ultrasonography. Follow-up was completed on Jan 13, 2021. All participants meeting the intention-to-treat principle were included in the analysis. This trial was registered with EudraCT (2013–003413–18). Findings: Between Dec 22, 2014, and Jan 14, 2019, 280 individuals were evaluated for eligibility and, of 213 participants, 110 were randomly assigned to abatacept and 103 to placebo. During the treatment period, seven (6%) of 110 participants in the abatacept group and 30 (29%) of 103 participants in the placebo group met the primary endpoint. At 24 months, 27 (25%) of 110 participants in the abatacept group had progressed to rheumatoid arthritis, compared with 38 (37%) of 103 in the placebo group. The estimated proportion of participants remaining arthritis-free at 12 months was 92\ub78% (SE 2\ub76) in the abatacept group and 69\ub72% (4\ub77) in the placebo group. Kaplan–Meier arthritis-free survival plots over 24 months favoured abatacept (log-rank test p=0\ub7044). The difference in restricted mean survival time between groups was 53 days (95% CI 28–78; p<0\ub70001) at 12 months and 99 days (95% CI 38–161; p=0\ub70016) at 24 months in favour of abatacept. During treatment, abatacept was associated with improvements in pain scores, functional wellbeing, and quality-of-life measurements, as well as low scores of subclinical synovitis by ultrasonography, compared with placebo. However, the effects were not sustained at 24 months. Seven serious adverse events occurred in the abatacept group and 11 in the placebo group, including one death in each group deemed unrelated to treatment. Interpretation: Therapeutic intervention during the at-risk phase of rheumatoid arthritis is feasible, with acceptable safety profiles. T-cell co-stimulation modulation with abatacept for 12 months reduces progression to rheumatoid arthritis, with evidence of sustained efficacy beyond the treatment period, and with no new safety signals. Funding: Bristol Myers Squibb

Eyes Up: A Reinforcement Learning-Based, Task-Relevant Sensor Selection Framework

To complete the task it was designed for, a robot must have the ability to obtain information from the outside world. This ability of perception usually involves rich capabilities, which give the robot a thorough understanding of its physical environment. In practice, robots with rich sensory capabilities become too sensitive to irrelevant environmental information, like background colors or textures. On the other hand, robots with insufficient sensory capabilities can fail to complete the task. I propose a novel reinforcement learning (RL) framework to automatically tune the richness of a robot’s sensory data. The intuition of my framework is to allow a robot to jointly discover control policies and select sensors; ideally, the robot’s elected sensors provide enough task-relevant information to complete a task. Results on a toy problem indicate that my framework finds a successful navigation policy while dropping out sensors that vanilla RL frameworks do not, but only after extensive training and hyperparameter tuning. The problem statement for another task, robot manipulation, is also presented. After a discussion of privacy and robotics, a topic motivated by my proposed framework, I conclude with proposed directions for future work

Weed management and grain yield of rice sown at low seeding rates in mechanized dry-seeded systems

Because of the rapid depletion of water and shortage of labor, farmers in many Asian regions are moving from puddled transplanted rice to dry-seeded rice. However, weed infestations are a serious problem in dry-seeded rice systems because dry cultivation practices and aerobic soil conditions are conducive to the germination and growth of weeds. A field study was conducted in the wet season of 2011 and the dry season of 2012 to evaluate the effect of two rice cultivars and different herbicides on weed growth and rice yield under dry-seeded rice. The rice cultivars (one hybrid and one inbred) were dry-seeded at 20-22kgseedha-1 with a combine drill fitted with knife-point openers. Rice plant densities ranged from 44 to 56plantsm-2 in the first season and from 67 to 77plantsm-2 in the second season. Weed density, weed biomass, rice panicle number, and rice yield were not influenced by the cultivars; however, they were strongly influenced by the weed control treatments. In terms of percent, the hybrid cultivar had 11-12% higher yield than the inbred cultivar. Weed competition in the control plots (one hand-weeding) lowered yield by 39-41% compared with the weed-free plots. All herbicides significantly reduced weed biomass compared with the control treatment, providing 75-93% weed control. Herbicide-treated plots had similar grain yield and the yield in these plots was 76-86% of the yield of the weed-free plots (4.2-4.4tha-1), suggesting further scope to improve rice yield in dry-seeded systems. Compared with the control treatment (one hand-weeding), herbicide-treated plots had 27-41% greater yield. Future research in dry-seeded rice systems should focus on the integration of appropriate agronomic practices with herbicide application timing and combinations to improve the effectiveness of weed management practices

Effect of tillage systems and herbicides on weed emergence, weed growth, and grain yield in dry-seeded rice systems

Farmers in many Asian countries are moving from puddled-transplanted rice to dry-seeded rice systems. Dry-seeded rice can be sown after land preparation or under zero-till conditions. Weeds, however, are the major constraint to the production of dry-seeded rice. A study was conducted during the wet season of 2011 and dry season of 2012 at the farm of the International Rice Research Institute to evaluate the effect of tillage systems (zero-till and conventional tillage) and herbicides on weed emergence, weed growth, and grain yield in dry-seeded rice systems. In the zero-till system, the densities of Digitaria ciliaris, Eleusine indica, Eclipta prostrata, and Ludwigia octovalvis increased many-fold from the first season to the second. The efficacy of herbicides (oxadiazon followed by fenoxaprop+ethoxysulfuron and oxadiazon followed by penoxsulam+cyhalofop) was lower in the zero-till system than in the conventional tillage system. Grain yield in the herbicide-treated and weed-free plots was similar between the tillage systems and this response was consistent during both the seasons. However, grain yield in the zero-till-control (one hand-weeded) plots was lower (0.9-1.5tha -1) than in the conventional tillage-control plots. The information gained from this study suggests that yields in zero-till systems similar to those in conventional-tilled systems can be achieved if weeds are effectively controlled. In the absence of effective weed control, zero-till systems may result in poor grain yield