On-farm management of rice genetic diversity: understanding farmers' knowledge on rice ecosystems and varietal development

The paper highlights the methodological development of identifying and characterizing rice (Oryza sativa L.) ecosystems and the varietal deployment process through participatory approaches. Farmers have intricate knowledge of their rice ecosystems. Evidence from Begnas (mid-hill) and Kachorwa (plain) sites in Nepal suggests that farmers distinguish ecosystems for rice primarily on the basis of moisture and fertility of soils. Farmers also differentiate the number, relative size and specific characteristics of each ecosystem within a given geographic area. They allocate individual varieties to each ecosystem, based on the principle of ‘best fit’ between ecosystem characteristics and varietal traits, indicating that competition between varieties mainly occurs within the ecosystems. Land use and ecosystems determine rice genetic diversity, with marginal land having fewer options for varieties than more productive areas. Modern varieties are mostly confined to productive land, whereas landraces are adapted to marginal ecosystems. Researchers need to understand the ecosystems and varietal distribution within ecosystems better in order to plan and execute programmes on agrobiodiversity conservation on-farm, diversity deployment, repatriation of landraces and monitoring varietal diversity. Simple and practical ways to elicit information on rice ecosystems and associated varieties through farmers’ group discussion at village level are suggested.

Microsaccades distinguish between global and local visual processing

Much is known about the functional mechanisms involved in visual search. Yet, the fundamental question of whether the visual system can perform different types of visual analysis at different spatial resolutions still remains unsettled. In the visual-attention literature, the distinction between different spatial scales of visual processing corresponds to the distinction between distributed and focused attention. Some authors have argued that singleton detection can be performed in distributed attention, whereas others suggest that even such a simple visual operation involves focused attention. Here we showed that microsaccades were spatially biased during singleton discrimination but not during singleton detection. The results provide support to the hypothesis that some coarse visual analysis can be performed in a distributed attention mode.

Statebuilding and governance: the conundrums of legitimacy and local ownership

The chapter explores the role of legitimacy in statebuilding. It first explores the concept of legitimacy and why it matters for successful statebuilding; it surveys how international statebilding efforts have tried to strengthen the legitimacy of post-conflict states; and examines the practices of local ownership in statebuilding, and how they relate to legitimation efforts.

Quantifying the relationship between temperature regulation in the ear and floret development stage in wheat (Triticum aestivum L.) under heat and drought stress

Thermal imaging is a valuable tool for the elucidation of gas exchange dynamics between a plant and its environment. The presence of stomata in wheat glumes and awns offers an opportunity to assess photosynthetic activity of ears up to and during flowering. The knowledge of spatial and temporal thermodynamics of the wheat ear may provide insight into interactions between floret developmental stage (FDS), temperature depression (TD) and ambient environment, with potential to be used as a high-throughput screening tool for breeders. A controlled environment study was conducted using six spring wheat (Triticum aestivum L.) genotypes of the elite recombinant inbred line Seri/Babax. Average ear temperature (AET) was recorded using a hand held infrared camera and gas exchange was measured by enclosing ears in a custom built cuvette. FDS was monitored and recorded daily throughout the study. Plants were grown in pots and exposed to a combination of two temperature and two water regimes. In the examined wheat lines, TD varied from 0.1°C to 0.6°C according to the level of stress imposed. The results indicated that TD does not occur at FDS F3, the peak of active flowering, but during the preceding stages prior to pollen release and stigma maturity (F1-F2). These findings suggest that ear temperature during the early stages of anthesis, prior to pollen release and full extension of the stigma, are likely to be the most relevant for identifying heat stress tolerant genotypes.