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[en] Sustainability analysis requires a joint assessment of environmental, social and economic aspects of production processes. Here we propose the use of Life Cycle Analysis (LCA), a metafrontier (MF) directional distance function (DDF) approach, and Data Envelopment Analysis (DEA), to assess technological and managerial differences in eco-efficiency between production systems. We use LCA to compute six environmental and health impacts associated with the production processes of nearly 200 Spanish citrus farms belonging to organic and conventional farming systems. DEA is then employed to obtain joint economic-environmental farm's scores that we refer to as eco-efficiency. DDF allows us to determine farms' global eco-efficiency scores, as well as eco-efficiency scores with respect to specific environmental impacts. Furthermore, the use of an MF helps us to disentangle technological and managerial eco-inefficiencies by comparing the eco-efficiency of both farming systems with regards to a common benchmark. Our core results suggest that the shift from conventional to organic farming technology would allow a potential reduction in environmental impacts of 80% without resulting in any decline in economic performance. In contrast, as regards farmers' managerial capacities, both systems display quite similar mean scores.
[en] By the availability of various mutant resources in Arabidopsis, it is now possible to investigate mutant lines for almost every gene. Arabidopsis is then, not only a model plant for plant research, but also a model species in which it is possible to carry out 'saturation mutagenesis' for all genes, and to totally analyze each gene and mutant of one organism. One of the future goals of the 'phenome' project is to collect information about the knockout-type mutant phenotypes for each Arabidopsis gene. We have generated thousands of Dissociation (Ds) transposon-tagged lines, which have a single insertion because of an advantage of the Activator/Dissociation (Ac/Ds) system, and deposited it to the RIKEN BioResource Center. In this resource, we selected 4,000 transposon-tagged lines with a transposon insertion in gene-coding regions, and systematically observed the visible phenotype of each line as a first step of phenome analysis. In total, about 200 clear visible phenotypes were classified into 43 categories of morphological phenotypes. Phenotypic images have been entered into a searchable database. Parallel to this, we have been selecting homozygous transposon-insertional plants, which would be useful resources to detect other phenotypes besides the visible ones. We are setting three categories of measurement to search various traits for total phenome analysis, such as physical, chemical or biological methods. Recently, we started to investigate biologically-measured phenotypes, which are stress-responsive or conditional phenotypes, using homozygous mutant resources. We are also collecting any mutant phenotype information from published reports in journal research activity to make a comprehensive phenotype database of Arabidopsis genes and mutants. (author)
[en] Gluten-free (GF) dry egg pappardelle was prepared with tigernut flour (50%), chickpea flour (50%) and pregelatinized TNF (0, 5, 10%), and compared to plain pasta (100% durum wheat semolina). The GF pasta may have a significant higher content of insoluble fibre, minerals and fat rich in oleic acid and a similar protein content. It was not found any clear relationship between the flour functional properties and its proximate composition. The use of PG did not imply an improvement on the firmness but did provide some continuity to the pasta structure. (Author)
[en] Basal leaves frequently senesce before anthesis in high population density crops. This paper evaluates the hypothesis that quantitative and qualitative changes in the light environment associated with a high leaf area index (LAI) trigger leaf senescence in sunflower (Helianthus annuus L.) canopies. Mean leaf duration (LD, time from achievement of maximum leaf area) of leaf 8 was significantly (P < 0.05) reduced from 51 to 19 days as crop population density was increased from 0.47 to 4.76 plants m−2. High compared to low plant population density was associated with earlier reduction in the photosynthetically active radiation (PAR) and red/far-red ratio (R/FR) reaching the target leaf. However the changes in R/FR preceded those in PAR. When the light environment of individual leaves of isolated plants growing under field conditions was manipulated using filters and FR-reflecting mirrors, LD was positively and linearly related with the mean daily PAR (MDR) received in the FR- (no FR enrichment) treatments. FR enrichment of light reaching the abaxial surface of the leaf significantly (P < 0.05) reduced LD by 9 days at intermediate PAR levels with respect to FR-controls, but did not affect LD at the maximum PAR used in these experiments. However, when light reaching both leaf surfaces was enriched with FR, LD (for leaves receiving maximum PAR) was 13 days shorter than that of the FR- control. These results show that basal leaf senescence in sunflower is enhanced both by a decrease in PAR and by a decrease in R/FR. (author)
[en] The research work was conducted at NIAB, Faisalabad and consists of three combinations of both F4 and F5 populations along with their parents and check varieties. In F4 generation significant differences for fibre strength and lint weight were observed whereas in F5 generation significant difference in micronaire, maturity, fibre length, fibre strength, lint weight were observed. Cross combination NIAB-2008 x MNH-886 form F4 generation and from F5, cross combination NIAB-852 x MNH- 886 followed by NIAB-777 x MNH-886 showed high mean values for fibre maturity, lint weight, micronaire and seed cotton yield per plant. In F4 and F/sub 5/ generations, seed cotton yield per plant was significantly and positively correlated with ginning out turn (GOT %), fibre maturity, fibre length, micronaire and lint weight at genotypic level. In both F4 and F5, path coefficient analysis showed that ginning out turn, fibre uniformity, fibre strength and lint weight had direct positive effects on seed cotton yield at both phenotypic and genotypic level. From the present findings it is concluded that cotton breeders can enhance the efficiency of selection with the help of information generated on the relationship between components associated with fibre quality and yield itself in the early generations. Both F/sub 4/ and F/sub 5/ generations exhibited highest direct effects combined with positive correlation in ginning out turn%, fibre length and lint weight with seed cotton yield. The result showed that while making selection these fibre traits should be given more emphasis. (author)
[en] The results of a research carried out in order to study the reflectance, absorptance and transmittance spectra of sunflower leaves as related to their stem position are reported. Two sunflower hybrids, which differed for growth habitus (''Monica'', with low size, and ''Hysun-32'' with normal size) were used. Reflectance, absorptance and transmittance spectra were measured in vivo when the plants were in the phases of appearance of inflorescence and anthesis. The measures were taken with a portable spectroradiometer with an external integrating sphere. The radiation over the wavelength range from 400 to 1,100 mm was measured at intervals of 1 mm. Absorptance was calculated. The results have evidenced that leaf position, related to its metabolic age, influence the capacity of reflecting, absorbing and transmitting the radiation in the photosynthetically active region. In the PAR region the variations are different with the spectral band considered. The leaves in medium-high position, as compared to the top and bottom leaves, have lower reflectance and transmittance values and higher absorptance values. No difference emerged in the near infrared region
[it]Vengono riportati i risultati diuna ricerca condotta al fine di studiare gli spettri della radiazione riflessa, assorbita e trasmessa dalle foglie di girasole in relazione alla loro posizione di inserimento sul fusto. Sono stati utilizzati due ibridi di girasole ben differenziati nell'habitus di crescita (''Monica'', a taglia bassa, e ''Hysun-32'' a taglia normale). Gli spettri della riflettanza e della transmittanza sono stati misurati in vivo in corrispondenza delle fasi di comparsa del bottone fiorale e di fioritura. Le misure sono state effettuate utilizzando uno spettroradiometro portatile dotato di sfera integrante di tipo esterno. e stata misurata, ad intervalli di 1mm, la radiazione compresa tra 400 e 1.100 nanometri. L'assorbanza e stata calcolata. I risultati ottenuti hanno evidenziato come nel girasole foglie inserite sul fusto in posizione diversa, e quindi con differente eta metabolica, presentino diversa capacita di riflettere, assorbire e trasmettere la radiazione nella regione del PAR. All'interno del PAR le variazioni sono risultate inoltre di entita diversa in dipendenza della banda spettrale considerata. Le foglie inserite in posizione medio-alta hanno presentato, rispetto a quelle apicali e basali, valori di riflettanza e di trasmittanza nettamente inferiori e valori di assorbanza nettamente superiori. Nessuna differenza e emersa nella regione dell'infrarosso vicino
[en] DiNitrogen-fixing capacity of four species of leguminous trees of Sri Lanka (Abarema bigemina, Adenanthera bicolor, Humboldtia laurifolia and Pericopsis mooniana) by analyzing their xylem sap and by taking acetylene reducyion (AR) measurements of nodulated roots of all species, except A.bicolor which had no nodules. Based on the results of the study on P.mooniana, a method to determine the C2H2/N2 conversion factor by analysing the total NH2 compounds is being developed
[en] Modeling genotype by environment interaction (GEI) is one of the most challenging aspects of plant breeding programs. The use of efficient trial networks is an effective way to evaluate GEI to define selection strategies. Furthermore, the experimental design and the number of locations, replications, and years are crucial aspects of multi-environment trial (MET) network optimization. The objective of this study was to evaluate the efficiency and performance of a MET network of sunflower (Helianthus annuus L.). Specifically, we evaluated GEI in the network by delineating mega-environments, estimating genotypic stability and identifying relevant environmental covariates. Additionally, we optimized the network by comparing experimental design efficiencies. We used the National Evaluation Network of Sunflower Cultivars of Uruguay (NENSU) in a period of 20 years. MET plot yield and flowering time information was used to evaluate GEI. Additionally, meteorological information was studied for each sunflower physiological stage. An optimal network under these conditions should have three replications, two years of evaluation and at least three locations. The use of incomplete randomized block experimental design showed reasonable performance. Three mega-environments were defined, explained mainly by different management of sowing dates. Late sowings dates had the worst performance in grain yield and oil production, associated with higher temperatures before anthesis and fewer days allocated to grain filling. The optimization of MET networks through the analysis of the experimental design efficiency, the presence of GEI, and appropriate management strategies have a positive impact on the expression of yield potential and selection of superior cultivars.
[en] In order to quantify the biological nitrogen fixation (BNF) and to evaluate the mycorrhiza effect in the BNF, an experiment was carried on by applying 15N-ammonium sulphate and mycorrhiza fungi to the soil. The treatments included legumes: mucuna negra(Stizolobium atterrinum Piper et Tracv) and caupi (Vigna unguiculoata L. Walp). Two control plants: non nodulating soybean (Glycine max L.Merril) and rice (Oryza sativa), were used for measuring the fixed N in the legumes by isotope dilution method. Both legumes and control plants assimmilated the same ammounts of nitrogen from the soil and fertilizer. The greater N content in the legumnes was determined as coming from the fixed nitrogen. Rice and non nodulating soybean showed to be good controls for measuring biological nitrogen fixation using isotopic dilution method. The values of fixed nitrogen for legumes calculated using rice as control plant were slightly greater than those with non nodulating soybean, nevertheless there were no significant statistical differences between the values. The mucuna fixed more N than caupi in both mycorrhiza treatments (76.7, 66.6 and 56. 7 per cent of N fixed, respectively). The mycorrhiza increased dry matter yield (13.84 per cent), accumulation of N in the plant(14.85 per cent N) and the biological N fixation (16.06 per cent N-fixed) in caupi
[en] Diploid cotton (Gossypium arboreum L.) being an Old World cultivated cotton species, evolved in Indo-Pak subcontinent, has been known for conferring resistance to biotic and abiotic stresses. To the extent of our knowledge, there is no comprehensive report available on the characterization of G. arboreum germplasm. Hence, the present study was conducted to characterize 26 G. arboreum genotypes by deploying univariate and multivariate analysis in 2010 at NIBGE, Faisalabad. All these genotypes were characterized for boll weight, GOT percentage, micronaire value, staple length, fiber bundle strength and uniformity index. Genotypic variation was significant (p<0.01) for all the analyzed traits except boll weight. Maximum boll weight (2.47g) was observed for genotype 23718. GOT ranged from 18.75% (Haroonabad) to 36.94 percentage (DC-116).The finest fiber was obtained from synthetic (4.37 micro g/inch) and this genotype also exhibited the higher values for staple length (23.81 mm) and fiber bundle strength (27.37 g/tex). Range for uniformity index was observed from 76.19 percentage (Garohill) to 77.98 percentage (212). Principal component analysis (PCA) exhibited that first five components accounted for >63 percentage of the total variability. Cluster analysis identified four groups based on their agronomic properties. Significant relationships among different traits can be useful to select best genotypes having good fiber quality traits. These genotypes may prove a valuable resource to fuel the breeding efforts for not only broadening the genetic base of the newly developed material but can also add synergy to various cotton genomic projects. (author)