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41.
The karyotypes of southern Italian samples of three species of the genus Allium L. belonging to the section Allium, were analyzed using Feulgen staining and C-banding techniques. Karyomorphological affinities and C-banding patterns clearly denote close phyletic relationships between A. commutatum Guss., A. ampeloprasum L. and A. atroviolaceum Boiss. Nevertheless, the karyotypes of the two tetraploid species revealed notable differences in the amount and distribution of C-banded heterochromatin. Marker chromosomes were identified which helped tracing evolutionary relationships among the three taxa considered. The results of morphological and karyological examinations allow the proposition of a possible phyletic pathway between the diploid species A. commutatum and the tetraploid ones A. ampeloprasum and A. atroviolaceum. The latter species seems to be particularly well adapted to southern Italian environments and might therefore contribute useful traits to closely related crops, such as leeks.  相似文献   
42.
The aim of this work was to study the effect of arbuscular mycorrhizal fungus Glomus mosseae on growth and nitrogen (N) metabolism of durum wheat (Tritcum durum) under various P soil contents. The analyses were extended to macro and micronutrient tissue concentrations, nitrate reductase and glutamine synthetase activities, as well as protein, aminoacids, pyridine dinucleotides and adenine nucleotides. Arbuscular mycorrhiza increased wheat growth in soil in which P availability was low and nitrate was the dominant N form. The root colonization occurred at the highest level in plants grown in limiting soil P and was inversely related to soil P content. The micorrhizal wheat plants contained also the highest concentrations of macro (P, K, Ca, N) and micronutrients (Fe, Zn, Mn) as well as free amino acids, protein, NAD, NADP, AMP, ADP, ATP in roots and leaves. In particular, the micronutrient tissue concentrations (Zn, Mn) supported that mycorrhiza actively modulated their uptake limiting interferences and optimizing growth better than the plant roots, like a very efficient “rootstock”. Control plants grown at the highest soil P did not reach the same concentration as the mycorrhizal plants. Nitrate reductase activities in the roots of mycorrhizal plants were higher than in the control ones, while glutamine synthetase activities were highest in the leaves. Protein and amino acids concentrations, as well as AMP, ADP, ATP, NAD(P), and NAD(P)H were also higher than in the control. Among the free amino acids in the roots, the high levels of glutamine, asparagine, arginine, support the view that ammonium was transferred through the arbuscules to the root cells where it was re‐assimilated in the cortical cells, forming high N : C ratio‐amino acids. They were transferred to the leaves where all the other N compounds could be largely synthesized using the carbon skeletons supplied by photosynthesis.  相似文献   
43.
A field experiment was carried out in Southern Italy from 2007 to 2010 adopting a two-year rotation of tomato and maize. In this paper, the results of maize cultivation were reported, with the aim to investigate the effects of different water qualities and fertilizers on yield and soil properties. The following treatments were compared: mineral nitrogen (N) fertilizer and irrigation with fresh water (FWF); mineral N fertilizer and irrigation with saline water (SWF); Municipal Solid Waste (MSW) compost and irrigation with fresh water (FWC); MSW compost and irrigation with saline water (SWC). These treatments were compared with an unfertilized control and irrigation with fresh-water (FW0) and an unfertilized control and irrigation with saline water (SW0). At harvest, yield, grain moisture content, dry matter, grain protein, starch, fat content and soil characteristics were determined. The treatments with compost increased the average grain yield of the 11% compared to mineral fertilizer treatments. Furthermore, the grain yield in SWC increased of the 19% respect to average of SWF and SW0, indicating that MSW compost applied as amendment mitigated the adversely effects of saline water. Compost application significantly increased the Total Organic Carbon (TOC). In particular, the FWC and SWC treatments showed an average increase of the 25% compared to the mean TOC value of FWF and SWF. Moreover, at the end of the experiment, electrical conductivity decreased in SWC treatment respect to the SWF (?21%).  相似文献   
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In 1970s it was thought that two species of ‘farro’, namely emmer (Triticum dicoccon Schrank) and einkorn (T. monococcum L.), were no longer present in Italy, but in 1981, some populations were discovered in a mountain area of the Appennino Sannita (central southern Italy). In 2006/2007 three monitoring missions were carried out to check the current situation of these ancient hulled wheats, specifically in the same areas where they were formerly collected. The same zones were also investigated by both paleo-ethnobotany and agrobiodiversity points of view. The results of this research have shown that nowadays einkorn is completely extinct while emmer is still cultivated in very few traditional farms, mainly as a fodder crop. A strong genetic erosion was detected also for emmer and several nowadays samples were contaminated by seeds of modern spelt (T. spelta L.) varieties. In the present study the causes of this genetic erosion and which safeguarding actions to be undertaken are discussed.  相似文献   
46.
The methodology for the inclusion of tebuconazole (TBC) in beta-cyclodextrin (betaCD), spectroscopic characterization of the inclusion complex, and its activity for the control of a major soilborne disease of wheat caused by Fusarium culmorum are reported. Controlled release measured by chemical shift of the diagnostic protons H(3) and H(5) of betaCD confirmed stability of the complex at the solid state and in aqueous solution. Greenhouse and field experiments were conducted on durum wheat (Triticum durum cv. Prometeo) sown in substrate or in soil artificially infested with a virulent strain of F. culmorum. The inclusion complex betaCD-TBC, applied as seed dressing in combination or not with carboxymethylcellulose, reduced the disease incidence caused by F. culmorum and improved grain yield, showing effects that were generally comparable to those observed upon application of a commercial formulation of TBC. In the field experiment, only seed treatment with the inclusion complex betaCD-TBC allowed yield that was not different from that obtained from the uninoculated control. These results prove that by the use of the betaCD-TBC complex it is possible to obtain release of TBC and bioavailabilty of the fungicide without compromising its effectiveness.  相似文献   
47.
In this work we detected the extent of variability at nuclear and cytoplasmic DNA level of regenerated plants belonging to Solanum genotypes with a different genetic background and somatic chromosome number. As for the nuclear characterization, a total of 66 (18.5%) polymorphic bands were scored using 13 ISSR primers on 45 randomly selected regenerants. Our results show that the regenerants obtained from clone cmm 1T and, at lower level, those from cph 1C are unstable under in vitro conditions or rather more prone to in vitro-induced stress leading to somaclonal variation than the other genotypes used. Two types of changes were observed: disappearance of parental ISSR fragments, termed “loss”; appearance of novel ISSR fragments, termed “gain”. The most frequent event occurring in the regenerants was the loss of fragments (41 bands). Regenerated plants were analyzed with seven plastid universal primers to determine the cytoplasmic composition at chloroplast level. All cpDNA primer pairs tested produced amplicons of the same size in all genotypes analyzed and no polymorphic fragments were observed with any universal primers used. Our results show that under in vitro culture conditions genotype affects the integrity of the genome. In addition, the absence of polymorphism at plastid level confirms the greater genetic stability of cytoplasmic DNA.  相似文献   
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49.
The aim of this study was to evaluate the effect of exogenous progesterone supplementation on superovulatory response in buffaloes that has undergone a multiple ovulation program. Fourteen Mediterranean buffaloes were divided into two groups and received a 4-day decreasing dosage of an equal mixture of 500 IU of FSH and LH starting on day 8 of the cycle. In group A (n = 7) a progesterone-releasing intravaginal device was removed on day 8, whereas in group B (n = 7) it was left till day 10, when PGF2a {\hbox{PG}}{{\hbox{F}}_{{2}\alpha }} was administered. Eighty hours later, buffaloes were artificially inseminated and after 6 days they undergone uterine flushing. A higher (P < 0.05) number of corpora lutea (8.3 vs. 5.7) and embryo/flushing/buffalo (2.3 vs. 1.3) were recorded in group B vs. group A if responsive buffaloes are considered (n = 12) and the number of corpora lutea was highly correlated with the number of embryos (r = 0.65; P < 0.05). In conclusion, progesterone supplementation during the first 2 days of the superovulation treatment seems to enhance the recovery rate in buffalo species. A high ovulation rate, associated with a high number of corpora lutea, can represent a parameter for estimating embryo recovery.  相似文献   
50.
Anthrax is a non-contagious disease, known since ancient times. However, it became a matter of global public interest after the bioterrorist attacks in the U.S.A. during the autumn of 2001. The concern of politicians and civil authorities everywhere towards this emergency necessitated a significant research effort and the prevention of new bioterrorist acts. Anthrax is primarily a disease that affects livestock and wildlife; its distribution is worldwide; and it can represent a danger to humans but especially more so when it occurs in areas considered to be free and in atypical seasons and climatic conditions. The atypicality of the phenomenon may lead health workers to misdiagnose and, consequently, an inappropriately manage of affected carcasses with a consequent and inevitable increase in the risk of human infection. This article emphasises the importance of paying increasing attention to this zoonosis. The biggest risk is its underestimation.  相似文献   
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