Participatory Varietal Selection for Promising Rice Lines

The purpose of rice breeding is to create varieties that are well adapted, highly productive, and acceptable to farmers. However, rice productivity is limited as a result of combined biotic stresses (pests/diseases). This study combines assessment by farmers with the evaluation by breeders with respect to promising rice lines within a range of environments. The aim is to investigate farmers’ preferences and to characterize the yield of promising rice lines, as well as their resistance to pests/diseases by consulting 120 farmers and breeders. This study used an oversite design replicated three times with thirteen promising lines and two varieties, which were all evaluated at farmers’ fields between December 2019 and May 2020. The Importance Performance Analysis was used to compare line performance and farmers’ expectations. Lines Gamapadi-2 and Gamapadi-4 had the highest acceptability scores based on the farmers’ preferences. The yield performances were evaluated using the Finlay–Wilkinson test and the genotypes were evaluated using environmental models (GGE biplot) to determine the most stable lines to be recommended for large-scale planting. The Finlay–Wilkinson and GGE biplot conclusion analyses also showed that the Gamapadi-2 and Gamapadi-4 lines exhibited high potential yield and stability, as well as indications of specific advantages. The results for both lines in all locations indicated no symptoms of damage caused by brown planthoppers or bacterial leaf blight. These lines in all age ranges at two sites showed no symptoms of leaf blast.

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Indirect selection for potential yield in early-generation, spaced plantings of wheat and other small-grain cereals: a review

Crop and Pasture Science ◽

10.1071/cp17409 ◽

2018 ◽

Vol 69 (5) ◽

pp. 439 ◽

Cited By ~ 40

Author(s):

R. A. Fischer ◽

G. J. Rebetzke

Keyword(s):

Stomatal Conductance ◽

Unit Cost ◽

Indirect Selection ◽

Breeding Systems ◽

Genotypic Differences ◽

Genetic Progress ◽

Early Generation ◽

Potential Yield ◽

Biotic Stresses ◽

Selection For

Early-generation (e.g. F2–F4) selection for grain yield itself is frustrated in particular by the small amounts of seed available. However, there has long been an interest in traits related to yield and reasonably faithfully expressed in spaced planting arrangements using little seed; these are potentially useful as indirect selection criteria for yield, with the view to increasing genetic progress per unit cost. This subject is revisited in this review, targeting potential yield (yield in the absence of abiotic and biotic stresses) of small-grain cereals. A brief assessment of current breeding systems for self-pollinated crops such as wheat reveals that all have some stage during which selection among visually acceptable spaced plants has to, or could, be practiced. The relative performance of different genotypes in such spaced plantings is then explored, highlighting interactions arising from intergenotypic competition as well as from the extra space itself. The theory of indirect selection is presented, along with some practical examples. After a brief survey of possible selection traits and developments in high-throughput measurement, harvest index, fruiting efficiency and stomatal conductance (and its surrogates) are chosen for in-depth review. All three traits show promise, especially in the light of possible new ways of reducing the cost of their measurement in early generations. Remote sensing of foliage temperature for the detection of genotypic differences in stomatal conductance makes this clearly the most promising trait for thorough testing in commercial breeding populations. Such traits could be used directly or they could complement genomic selection in early generations.

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Performance Analysis of (X,S)-Bottleneck Cell in Large-Scale Wireless Networks

Journal of Software ◽

10.3724/sp.j.1001.2012.03968 ◽

2012 ◽

Vol 23 (2) ◽

pp. 323-334

Author(s):

Guo-Feng YAN ◽

Jian-Xin WANG ◽

Shu-Hong CHEN

Keyword(s):

Wireless Networks ◽

Performance Analysis ◽

Large Scale

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Performance Analysis and Design Considerations of the Shallow Underwater Optical Wireless Communication System with Solar Noises Utilizing a Photon Tracing-Based Simulation Platform

Electronics ◽

10.3390/electronics10050632 ◽

2021 ◽

Vol 10 (5) ◽

pp. 632

Author(s):

Xiaozheng Wang ◽

Minglun Zhang ◽

Hongyu Zhou ◽

Xiaomin Ren

Keyword(s):

Performance Analysis ◽

Wireless Communication ◽

Ambient Noise ◽

Large Scale ◽

Delay Spread ◽

Simulation Platform ◽

Optical Wireless Communication ◽

Optical Wireless ◽

Analysis And Design ◽

The Impact

The performance of the underwater optical wireless communication (UOWC) system is highly affected by seawater´s inherent optical properties and the solar radiation from sunlight, especially for a shallow environment. The multipath effect and degradations in signal-to-noise ratio (SNR) due to absorption, scattering, and ambient noises can significantly limit the viable communication range, which poses key challenges to its large-scale commercial applications. To this end, this paper proposes a unified model for underwater channel characterization and system performance analysis in the presence of solar noises utilizing a photon tracing algorithm. Besides, we developed a generic simulation platform with configurable parameters and self-defined scenarios via MATLAB. Based on this platform, a comprehensive investigation of underwater channel impairments was conducted including temporal and spatial dispersion, illumination distribution pattern, and statistical attenuation with various oceanic types. The impact of ambient noise at different operation depths on the bit error rate (BER) performance of the shallow UOWC system was evaluated under typical specifications. Simulation results revealed that the multipath dispersion is tied closely to the multiple scattering phenomenon. The delay spread and ambient noise effect can be mitigated by considering a narrow field of view (FOV) and it also enables the system to exhibit optimal performance on combining with a wide aperture.

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