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1.
In the United States, yellow starthistle (Centaurea solstitialis) is an annual invasive weed with Mediterranean origins. Malformed plants displaying witches' broom, fasciations, abortion of buds and flower virescence symptoms were observed in central Italy. Attempts to transmit the causal agent from the natural yellow starthistle host to periwinkle by grafting, resulted in typical symptoms of a phytoplasma, i.e. yellowing and shortening of internodes. The detection of phytoplasmas was obtained from both symptomatic yellow starthistle and periwinkle by the specific amplification of their 16S-23S rRNA genes. PCR amplification of extracted DNA from symptomatic plant samples gave a product of expected size. Asymptomatic plants did not give positive results. An amplicon obtained by direct PCR with universal primers P1/P7 was cloned and sequenced. The homology search using CLUSTALW program showed more than 99% similarity with Illinois elm yellows (ILEY) phytoplasma from Illinois (United States) and 97% with Brinjal little leaf (BLL) phytoplasma from India. Digestion of the nested-PCR products with restriction enzymes led to restriction fragment length polymorphism patterns referable to those described for phytoplasmas belonging to the clover proliferation (16S-VI) group. Since this is a previously undescribed disease, the name Centaurea solstitialis virescence has been tentatively assigned to it. This is a new phytoplasma with closest relationships to ILEY and BLL, but distinguishable from them on the basis of 16S rDNA homology, the different associated plant hosts and their geographical origin.  相似文献   
2.
A study was conducted to evaluate a non-destructive method able to predict Magness–Taylor (MT) penetrometric firmness of blood oranges, potentially applicable for on-line selection. The method consisted of multivariate modelling of non-destructive penetrometric measurements performed on intact oranges with a 11.3 mm diameter probe by digital dynamometric equipment. The tests were carried out on 366 blood oranges (Citrus sinensis (L.) Osbeck cv. Tarocco); 60 were used as a control group to verify the non-destructive nature of the tests. Four test factors were used on the fruit: two different levels of non-destructive deformation (1 and 3 mm), at two different deformation speeds (5 and 30 mm s?1). In order to obtain the reference parameter (MT firmness), a destructive penetrometric test followed each non-destructive deformation on the same fruit (deformation of 20 mm at 1 mm s?1). The force–deformation curves of the non-destructive tests were elaborated to calculate different texture parameters (max force, elasticity, work). These parameters with raw curve data (force values for constant deformation steps) were used, after autoscaling pre-processing, as X-block datasets in supervised multivariate modelling (partial least squares) to predict MT firmness values. Among the test factors used, the 30 mm s?1 speed and 3 mm deformation provided the best overall prediction of MT firmness. This comprised an r value of 0.76 and standard error of prevision (SEP) of 2.99 N for a MT firmness mean value of 35.65 N (8.4%). The time needed to apply the selected deformation may lead to a sorting speed of about 10 fruit per second, representing an acceptable value for commercial application.  相似文献   
3.
Agroforestry Systems - The use of native trees in agroecosystems is a promising way to increase litter deposition and nutrient cycling and foster the recovery of degraded areas, especially in...  相似文献   
4.
Buffalo milk represents an indispensable source of nourishment in many parts of the world and it is the second most consumed milk worldwide. Buffalo milk is actually used for the production of many dairy products such as pasteurized or concentrated milk, butter, yogurt, ice‐cream, dehydrated milk products and cheeses. Due to its high nutritional value and the presence of natural bioactive substances, buffalo milk can also provide health benefits to consumers. In Italy, buffalo milk is used mainly for cheese making, mozzarella PDO (Protected Designation of Origin), which is a highly valued dairy product. This 3‐year study, carried out between 2011 and 2013, was aimed at evaluating the quality of bulk Italian Mediterranean buffalo milk by monitoring physico‐chemical parameters, somatic cell and total bacterial counts. A total of 51 samples of bulk milk were collected from one herd throughout the monitored period. Analysis of variance, carried out to test month, season and year main effects, highlighted remarkable seasonal effects for fat, protein and lactose content, as well as for predicted mozzarella cheese yield, and somatic cell counts. The calculation of simple correlations allowed the identification of positive correlations between estimated cheese yield and fat and protein content.  相似文献   
5.
It is becoming increasingly difficult to manage and expand statutory conservation areas (i.e., parks and formally protected areas). Therefore, alternative opportunities for land conservation merit closer attention. This paper examines the extent to which privately owned conservation areas contribute to biodiversity representation. Gap analyses were performed for a large semi-arid region in South Africa with a comprehensive database of private conservation areas. The distribution of private conservation areas was compared to statutory conservation areas using several landscape characteristics: biome and vegetation variant, elevation class, ecological process area, total area, and threat status (endangerment). Conservation target achievement for the vegetation variants was also assessed, as was the degree to which private conservation areas complemented statutory conservation areas by representing different landscape characteristics. The number of targets achieved nearly tripled if private conservation areas were considered in addition to statutory conservation areas. Further, private conservation areas significantly complemented statutory conservation areas in the types of biomes, elevation classes, and threat status classes conserved. Private conservation areas were especially important in conserving lower elevation habitat, and by association, endangered vegetation. This particular relationship is expected to be common worldwide. Our results indicate that private lands conservation deserves an increased allocation of resources for both research and implementation.  相似文献   
6.
This review covers both physical and chemical modifications of cellulose fibre surface and their impact on the properties of the ensuing papers. It is not restricted to actual industrial operations, but also deals instead with ongoing research in this area, which appears promising in terms of possible applications to papermaking.  相似文献   
7.
Numerous plants ofSilene nicaeensis having symptoms resembling those associated with the presence of phytoplasmas were observed in an extensive coastal area in the south of Italy. Microscopic observation showed histological abnormalities in the organization of tissues in symptomatic plants, and molecular tests, including PCR/RFLP analyses and nucleic acid sequencing, revealed the presence of phytoplasmas belonging to the aster yellows group (‘Candidatus phytoplasma asteris’). This is the first report of phytoplasma infection inS. nicaeensis, a wild species that colonizes the Calabrian coast. http://www.phytoparasitica.org posting June 12, 2008  相似文献   
8.
In order to extend scientific knowledge on autochthonous Italian equine meat, the physical–chemical parameters of Catria Horse Longissimus thoracis (LT) muscle and its nutritional characteristics have been investigated. Ten steaks of Catria foal raised at pasture and fattened indoors for 2 months were dissected, and LT muscle was analyzed for chemical composition, total iron, drip loss, colorimetric characteristics, intramuscular fat, fatty acid profile and nutritional indexes. Steak dissection showed that LT muscle accounted for 36.78% and fat accounted for 9.19% of weight of steak. Regarding chemical composition, protein and fat content was 20.31% and 2.83%, respectively. Total iron content (1.95 mg/100 g) was lower than data reported in the literature. Color parameters showed a luminous and intense red hue muscle. The sum of unsaturated fatty acid composition (50.3%) was higher than the sum of saturated fatty acids (46.64 %). The fatty acid profile and nutritional values of Catria Horse meat could be modified adopting extensive rearing systems and grazing. The data suggests that further investigation on the composition of Catria Horse meat should be carried out to valorize this autochthonous breed, reared in sustainable livestock systems, and its meat in local short‐chain systems.  相似文献   
9.
10.
Epidemiological field controls in different Italian locations and seedling evaluations of the ‘Thatcher’ near-isogenic lines (NILs) carrying the leaf rust resistance genes Lr1, Lr9, Lr24 and Lr47 were conducted during 5 years of testing. These genes confirmed their effectiveness in both field and greenhouse conditions. Moreover a backcross program was carried out by using as recurrent parents the susceptible high-quality common wheat cvs ‘Bolero’, ‘Colfiorito’, ‘Serio’ and ‘Spada’ and the ‘Thatcher’ NILs carrying the above mentioned genes as donor parents. The progenies of different cross combinations were selected by both resistance tests and marker assisted selection using molecular markers (STS, SCAR, CAPS) closely linked to Lr genes: a complete cosegregation was observed between the resistance genes used and the corresponding molecular markers.  相似文献   
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