Water-wise Rice Production

Rice is a profligate user of water. It takes 3,000–5,000 liters to produce 1 kilogram of rice, which is about 2 to 3 times more than to produce 1 kilogram of other cereals such as wheat or maize. Until recently, this amount of water has been taken for granted. Now, however, the water crisis threatens the sustainability of the irrigated rice ecosystem. In Asia, 17 million ha of irrigated rice areas may experience ‘physical water scarcity’ and 22 million ha ‘economic water scarcity’ by 2025. To safeguard food security and preserve precious water resources, ways must be explored to grow rice using less water. IRRI, together with Plant Research International of Wageningen University and Research Centre, organized a thematic workshop on Water-Wise Rice Production held 8-11 April 2002 at IRRI, Los Baños, Philippines. The objectives were to present and discuss the state-of-the-art in the development, dissemination, and adoption of water-saving technologies at spatial scales ranging from the field to irrigation system. This book contains the papers presented at the workshop

Assessment of RNAi-induced silencing in banana (Musa spp.)

In plants, RNA- based gene silencing mediated by small RNAs functions at the transcriptional or post-transcriptional level to negatively regulate target genes, repetitive sequences, viral RNAs and/or transposon elements. Post-transcriptional gene silencing (PTGS) or the RNA interference (RNAi) approach has been achieved in a wide range of plant species for inhibiting the expression of target genes by generating double-stranded RNA (dsRNA). However, to our knowledge, successful RNAi-application to knock-down endogenous genes has not been reported in the important staple food crop banana

Model Transformation as Conservative Theory-Transformation

This is the final version. Available on open access from the Journal of Object Technology via the DOI in this recordModel transformations play a central role in model-driven software development. Hence, logical unsafe model transformation can result in erroneous systems. Still, most model transformations are written in languages that do not provide built-in safeness guarantees. We present a new technique to construct tool support for domain-specific languages (DSLs) inside the interactive theorem prover environment Isabelle. Our approach is based on modeling the DSL formally in higher-order logic (HOL), modeling the API of Isabelle inside it, and defining the transformation between these two. Reflection via the powerful code generators yields code that can be integrated as extension into Isabelle and its user interface. Moreover, we use code generation to produce tactic code which is bound to appropriate command-level syntax. Our approach ensures the logical safeness (conservativity) of the theorem prover extension and, thus, provides a certified tool for the DSL in all aspects: the deductive capacities of theorem prover, code generation, and IDE support. We demonstrate our approach by extending Isabelle/HOL with support for UML/OCL and, more generally, providing support for a formal object-oriented modeling method

Impact of alternate wetting and drying irrigation on rice growth and resource-use efficiency

Crop-based irrigationRiceFertilizersNitrogenRainCrop yieldPercolationSeepagePaddy fieldsExperiments

Recent Developments in OCL and Textual Modelling

The panel session of the 16th OCL workshop featured a lightning talk session for discussing recent developments and open questions in the area of OCL and textual modelling. During this session, the OCL community discussed, stimulated through short presentations by OCL experts, tool support, potential future extensions, and suggested initiatives to make the textual modelling community even more successful. This collaborative paper, to which each OCL expert contributed one section, summarises the discussions as well as describes the recent developments and open questions presented in the lightning talks

Effectiveness and safety of in vitro maturation of oocytes versus in vitro fertilisation in women with high antral follicle count : Study protocol for a randomised controlled trial

This work was supported by Ferring grant number 000323 and sponsored by My Duc Hospital.Peer reviewedPublisher PD

Maximizing genetic representation in seed collections from populations of self and cross-pollinated banana wild relatives

Background: Conservation of plant genetic resources, including the wild relatives of crops, plays an important and well recognised role in addressing some of the key challenges faced by humanity and the planet including ending hunger and biodiversity loss. However, the genetic diversity and representativeness of ex situ collections, especially that contained in seed collections, is often unknown. This limits meaningful assessments against conservation targets, impairs targeting of future collecting and limits their use. We assessed genetic representation of seed collections compared to source populations for three wild relatives of bananas and plantains. Focal species and sampling regions were M. acuminata subsp. banksii (Papua New Guinea), M. balbisiana (Viet Nam) and M. maclayi s.l. (Bougainville, Papua New Guinea). We sequenced 445 samples using suites of 16–20 existing and newly developed taxon-specific polymorphic microsatellite markers. Samples of each species were from five populations in a region; 15 leaf samples from different individuals and 16 seed samples from one infructescence (‘bunch’) were analysed for each population. Results: Allelic richness of seeds compared to populations was 51, 81 and 93% (M. acuminata, M. balbisiana and M. maclayi respectively). Seed samples represented all common alleles in populations but omitted some rarer alleles. The number of collections required to achieve the 70% target of the Global Strategy for Plant Conservation was species dependent, relating to mating systems. Musa acuminata populations had low heterozygosity and diversity, indicating self-fertilization; many bunches were needed (> 15) to represent regional alleles to 70%; over 90% of the alleles from a bunch are included in only two seeds. Musa maclayi was characteristically cross-fertilizing; only three bunches were needed to represent regional alleles; within a bunch, 16 seeds represent alleles. Musa balbisiana, considered cross-fertilized, had low genetic diversity; seeds of four bunches are needed to represent regional alleles; only two seeds represent alleles in a bunch. Conclusions: We demonstrate empirical measurement of representation of genetic material in seeds collections in ex situ conservation towards conservation targets. Species mating systems profoundly affected genetic representation in seed collections and therefore should be a primary consideration to maximize genetic representation. Results are applicable to sampling strategies for other wild species