CREA Journals (Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria)
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First records of Charipinae (Hymenoptera Cynipoidea Figitidae) from the Corsica island
Get PDFCharipinae fauna from the Corsica Island has been studied. Five Alloxysta and one Apocharips species are cited for the first time in this island: Alloxysta arcuata (Kieffer, 1902), A. brevis (Thomson, 1862), A. castanea (Hartig, 1841), A. citripes (Thomson, 1862), A. victrix (Westwood, 1833) and Apocharips trapezoidea (Hartig, 1841). These identifications are the first record of these two genera and the Charipinae subfamily from the Corsica Island. Short descriptions and diagnoses are given for all Charipinae species present in this island. A key to distinguish them is also given
Genetic analysis and assessment of stay-green traits in hybrids of temperate and tropical maize germplasm
Get PDFLeaf stay-green is a trait in which plants retain leaves with green tissue from flowering through physiological ma¬turity in maize. To assess whether this characteristic improved grain filling in maize, we analyzed five stay-green traits, five grain yield-related traits, and three photosynthetic parameters in 10 hybrids derived from an incomplete diallele cross mating design between five temperate and two tropical maize germplasm inbred lines. The hybrids were grown in three different environments. The degree of stay-green (DSG) was significantly positively correlated with grain yield, ear length, number of grains per row, number of visible green leaves at maturity (MNL), ratio of visible source leaves (RSL), and photosynthetic potential at maturity (MPP). The highest correlation between traits was between RSL and MNL. All five stay-green traits were significantly positively correlated with net photosyn¬thetic rate (Pn). RSL had the highest broad-sense heritability among the stay-green traits evaluated. Our findings suggest that RSL is an important stay-green trait and can be used as a selection criterion for improving stay-green traits in maize breeding programs
Soil respiration rate in summer maize field under different soil tillage and straw application
Get PDFDemanding for food security and current situation of global warming give a high and strict request to North China Plain in food production and inhibition of agricultural carbon emission. To explore the effective way to decrease CO2 emission and remain high grain yield, in 2012 summer maize growing season from a long term project in North China Plain, soil organic carbon, soil CO2-C evolution rate, soil temperature, grain yield, and ratio of soil respiration to grain yield in different soil tillage and straw application treatments were invested. The results showed that in 0-20 cm soil layer, the organic carbon in no tillage was significantly higher than that in conventional tillage. Both in no tillage and conventional tillage, straw application could enhance the soil organic carbon concentrations at ma¬turity. The mean soil CO2-C evolution rate in no tillage was significantly lower than that in conventional tillage; how¬ever, straw application could significantly increase soil CO2-C evolution rate, no matter in no tillage or conventional tillage. This result was mainly due to the changes in soil organic carbon, soil total porosity, and soil temperature. No tillage and straw application result in a significantly increase in grain yield and ratio of soil respiration to grain yield of summer maize. The result obtained in field crop conditions support the idea that both no tillage and straw application affect CO2 emissions in North China Plain
Effect of grazing intensities and seed furrow openers on corn development and yield in a crop-livestock system
Get PDFGrazing intensity determines both agricultural and livestock production and may shift the crop-livestock system either in a positive or negative direction. High grazing intensity may affect soil physical-chemical and biological traits, affecting a no-tillage system and as a result, reduce crop yields. These effects can be mitigated by the use of a no-till seed planter equipped with different furrow openers that can interact to optimize crop yield. This study aimed to evaluate grazing intensities and seed furrow openers on corn crop development and yield in an integrated crop-livestock system. The experiment was laid out as random block design in a split-plot arrangement with four replications. Black oat + ryegrass grazing intensities were characterized by different pasture sward management, with the entrance of grazing animal at pasture heights of 25, 30, and 35 cm and exit at heights of 5, 10, and 15 cm, respectively. Grazing was a rotational basis with a treatment without grazing as a control. After the grazing period, corn was established using two seed furrow openers (double disc and shank) in the sub-plot level. Soil bulk density was evaluated before and after the grazing period as well as the depth of seed deposition, corn plant development, corn yield components and yield. Soil bulk density increased as grazing intensity increased. Corn yield dynamics were affected by grazing intensity and the type of seed furrow opener
Over-expression of glutamine synthetase genes Gln1-3/Gln1-4 improved nitrogen assimilation and maize yields
Get PDFIn agriculture, certain fertilizers that contain nitrogen generally tend to provide the most macronutrients for plant growth and development. The cDNAs of Gln1-3 and Gln1-4 genes, encoding glutamine synthetase isoenzymes (GS1), were fused to the rice actin1 promoter and over-expressed in the inbred maize line DH9632 by Agrobacte¬rium-mediated genetic transformation. PCR assays demonstrated the integration of these genes in six transgenic lines. Transcription of Gln1-3 or Gln1-4 in the transformants was also confirmed by semi-quantitative RT-PCR and qRT-PCR; the transgenic lines had significantly higher expression compared with wild type. Transgenic lines L2 and L7 expressed the most Gln1-3 and Gln1-4 mRNA, respectively, and had the most enzyme activity in leaves below the ear after pollination for 14 days. Over-expression of these two genes led to increased chlorophyll con¬tent and improved photosynthesis after 14 days. In addition, yield-related traits such as ear length, ear diameter, ear weight, grain weight per ear, and hundred-kernel weight were improved in the transgenic lines. The plot yield of transgenic L2 was increased by approximately 20%. These results suggest that overexpression of Gln1-3 and Gln1-4 in maize improves yields and enhances nitrogen using efficiency. Thus, transgenic lines overexpressing Gln1-3 or Gln1-4 in maize could potentially be used in maize breeding
Quality protein introduced into waxy maize landraces of ethnic minorities
Get PDFEthnic minorities in South East Asia use waxy maize as a staple food, lacking in essential amino acids. Recently, we combined the recessive waxy and opaque2 alleles to double quality grains (w/o, pure amylopectin, high quality protein), which still must be introgressed into germplasm acceptable to ethnic minorities. Two w/o lines of Chinese and Thai background, respectively, were crossed once with two Vietnamese waxy landraces of good taste, WVN 3 and WVN 10. At the preferred harvest time for eating, dough stage, homozygous w/o F2 offspring with WVN 3 were equal in dehusked ear yield with commercial waxy hybrids and 40% superior in yield compared with WVN 10 F2 offsprings. In WVN 3 F2 crosses and F2 backcrosses with WVN 3, all w/o dehusked ears were equal in eat¬ing quality, grain protein content and a good leaf health; but the yield of dehusked ears and the grain tryptophan content was highest in the topcross. High quality germplasm is available now as a source of high quality protein for ethnic minorities. The two original w/o lines led to equal results in crosses with landraces, but their test hybrid was extremely high-yielding, indicating a good potential to breed for commercial high protein quality snacks in South East Asia
Detection of genetic diversity of seven maize races from the high central valleys of Mexico using microsatellites
No full textIn Mexico there is a broad diversity of maize. To design schemes of genetic improvement and germplasm con¬servation, this diversity must first be assessed. In this context, an analysis of microsatellites was conducted to estimate the degree of variation and to analyze the structure and genetic diversity of seven maize (Zea mays L) landraces from the High Central Valleys of Mexico (Arrocillo Amarillo, Cacahuacintle, Chalqueño, Cónico, Elotes Cónicos, Palomero Toluqueño and Purépecha) as well as the teosinte races Chalco [Zea mays ssp. mexicana (Schrader) Iltis] and Balsas [Zea mays ssp. parviglumis (Iltis and Doebley)]. Seed from 107 accessions kept in Mexican germplasm banks was used. We analyzed 31 SSR loci to estimate genetic variation based on the number of alleles per locus, proportion of polymorphic loci and index of expected heterozygosity, and genetic structure using Wright F statistics. Races were grouped based on principal component and cluster analyses. A total of 636 alleles were identified, averaging 20.52 alleles per locus, 92.75% of which were polymorphic loci. Also found were 100 alleles exclusive of some of the studied populations. Occurrence of these alleles was low, representing 16% of the total alleles found. It was determined that 76.3% of the genetic diversity of the cultivated landraces of the High Valleys of Mexico resides within populations and the remaining 23.7% is between populations. Well-defined groups of the races Cacahuacintle and Purépecha, as well as two groups of the Chalqueño race, were observed. The Purépecha race formed a compact group separate from the rest, while a large sample of the Elotes Cónicos race group was placed intermediately among one of the groups of the Chalqueño race
Multifunctionality assessment in forest planning at landscape level. The study case of Matese Mountain Community (Italy).
Get PDFThe main objective is to improve a method that aims at evaluating forest multifunctionality from a technical and practical point of view. A methodological approach - based on the index of forest multifunctionality level - is proposed to assess the “fulfilment capability” of a function providing an estimate of performance level of each function in a given forest. This method is aimed at supporting technicians requested to define most suitable management guidelines and silvicultural practices in the framework of a Forest Landscape Management Plan (FLMP). The study area is the Matese district in southern Apennines (Italy), where a landscape planning experimentation was implemented. The approach includes the qualitative and quantitative characterization of selected populations, stratified by forest category by a sampling set of forest inventory plots. A 0.5 ha area around the sample plot was described by filling a form including the following information: site condition, tree species composition, stand origin and structure, silvicultural system, health condition, microhabitats presence. In each sample plot, both the multifunctionality assessment and the estimate of the effect of alternative management options on ecosystem goods and services, were carried out. The introduction of the term “fulfilment capability” and the modification of the concept of priority level - by which the ranking of functions within a plot is evaluated - is an improvement of current analysis method. This enhanced approach allows to detect the current status of forest plot and its potential framed within the whole forest. Assessing functional features of forests with this approach reduces the inherent subjectivity and allows to get useful information on forest multifunctionality to support forest planners in defining management guidelines consistent with current status and potential evolutive pattern
Status and trend of atmospheric deposition chemistry at the CONECOFOR plots, 1998-2005
Get PDFIon deposition in the open field and under the canopy was monitored in 13 CONECOFOR plots during 1998-2005. In spite of the remote location of most plots, atmospheric deposition carries considerable amounts of anthropogenic ions (sulphate, nitrate and ammonium). Deposition acidity is buffered by the deposition of base cations, partially due to the long-range transport of Saharan dust. In the study period, sulphate deposition and deposition acidity significantly decreased, because of the decrease in sulphur dioxide emissions in Europe, while nitrate and ammonia deposition did not show a clear temporal pattern
Status and changes in key meteorological variables at the CONECOFOR plots, 1996 - 2005
Get PDFIn this paper, variability of precipitation, temperatures and temperature stress indexes of permanent monitoring plots (PMPs) of Italian CONECOFOR network are analyzed. The study is carried out in 16 Open Field areas over the period 1996-2005. For four areas among these (BOL1, EMI1, VAL1, VEN1) longer time series are considered. An eventual trend in time series is analysed using the Mann- Kendall test, applied to annual and seasonal values, and using the additive stochastic model to separate the seasonal variation, despite the limited number of available data. Both methods do not show clear temperature or precipitation trends on long-term period. Changes in annual climatic parameters for different areas may be related to fluctuations on short-term period