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Cereal-legume intercropping can increase yields, reduce fertilizer input and improve soil quality compared with pure culture. Designing intercropping systems requires the integration of plant species trait selection with choice of crop configuration and management. Crop growth models can facilitate the understanding and prediction of the interactions between plant traits, crop configuration and management. However, currently no existing crop growth model has been calibrated and tested for cereal-legume intercrops throughout Europea. We calibrated the Agricultural Production Systems sIMulator (APSIM) for pure cultures of wheat and faba bean using data from Dutch field trials, and determined the phenological parameters to simulate pure cultures and intercrops from seven field experiments across Europe. APSIM successfully reproduced aboveground dry matters and, for wheat only, grain yields in pure cultures. In intercrops, APSIM systematically overestimated the aboveground dry matter and grain yield of faba bean and underestimated those of wheat. APSIM was reasonably capable of simulating plant heights in pure cultures, but respectively overestimated and underestimated the height of faba bean and wheat in intercrops. In order to simulate wheat-faba bean intercrops better, APSIM should be improved regarding the calculation of biomass partitioning to grains in faba bean and of height growth in both species.

Mixed cultivation of two or more crop species on the same piece of land at a given time may enhance crop yield stability. We assessed yield stability by first calculating the expected coefficients of variance (CV%) for cereal-legume mixtures grown across contrasting environments based on the corresponding yield variation of the mixture components grown separately in pure cultures; and then dividing the expected CV% by the observed CV% for each mixture. The ratio between the expected and observed CV% is the stability index, with values >1 indicating greater stability of the mixed crops and values 3.7. The results are relevant in the discussion of crop mixtures as means to increase yield stability.

The ban of raw GMO materials for preparation of feedstuff (Law 422 29/12/00) has steered the animal productive system to find alternative grain of legumes to replace soybean meal as protein source for animal feeding. There are few research about performance of heavy pig fed with grasspea. In a review Hambury et al. (2000) reported that in pig’s diet the substitution rates is up to 30%. The goal of this research was to evaluate the effect of partial replacing soybean meal and barley with grasspea (Lathyrus sativus L.) on fattening and slaughtering performance of pigs.........

The widespread occurrence of 2n gametes (i.e. gametes with the somatic chromosome number) in the Medicago sativa-coerulea-falcata complex supports the concept that gene flow from diploid to tetraploid species occurs continuously in nature and plays a key role in alfalfa evolution. Breeders realized early that gene transfer between ploidy levels via 2n pollen and 2n eggs would have had potential use in cultivated alfalfa improvement. Cytological investigations provided insights into the types of meiotic abnormalities responsible for the production of 2n gametes. Alterations were defined as genetically equivalent to first (FDR) or second division restitution (SDR) mechanisms. For breeding purposes,data have proven that 2n gametes of the FDR type are more advantageous than those obtained by SDR for transferring parental heterozygosity and retaining epistatic interactions. The use of diploid meiotic mutants that produce 2n gametes is now recognized as one of the most effective methods available for exploiting heterosis and introgressing wild germplams traits into cultivated tetraploid alfalfa via unilateral (USP) and bilateral sexual polyploidization (BSP) schemes. A main goal in alfalfa breeding could be the introduction of functional apomixis (i.e. apomeiosis and parthenogenesis) in cultivated alfalfa stocks. In the future, the efficiency of alfalfa breeding programs based on the use of reproductive mutants could be improved by direct selection at the genotype level using RFLPs and PCR-based markers. Molecular markers have recently been used in alfalfa for studying the inheritance of 2n gamete formation and identifying polymorphisms associated to genes involved in meiotic abnormalities. Molecular tagging of 2n egg and 2n pollen formation not only should explain the genetic control and regulation of these traits, but may also be an essential step towards marker-assisted selection of 2n gamete producers and implementation of USP and BSP breeding schemes. Future perspectives include strategies for the map-based cloning of genomic DNA markers, and screeing of EST mini-libraries related to flowers at different developmental stages from meiotic mutants and wild-types can lead to the identification of mRNAs and thus of candidate genes that control 2n gamete formation in alfalfa.

Mixed cultivation of two or more crop species on the same piece of land at a given time may enhance crop yield stability. We assessed yield stability by first calculating the expectedcoefficients of variance (CV%) for cereal-legume mixtures grown across contrastingenvironments based on the corresponding yield variation of the mixture components grownseparately in pure cultures; and then dividing the expected CV% by the observed CV% foreach mixture. The ratio between the expected and observed CV% is the stability index, withvalues >1 indicating greater stability of the mixed crops and values 3.7. The results are relevant in the discussionof crop mixtures as means to increase yield stability.