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451.
Journal of Plant Diseases and Protection - In a survey of Botrytis populations in Northern Germany in 2012-2014, an average of 67.7% and 73.8% of isolates from strawberry and raspberry fields... 相似文献
452.
Dionisio Andújar Victor Rueda-Ayala José Dorado Roland Gerhards César Fernández-Quintanilla 《Gesunde Pflanzen》2014,66(1):17-22
Sorghum halepense (L.) Pers. is one of the most troublesome weeds in warm climates. Its control is difficult, and understanding the factors affecting its spreading is crucial. A study was conducted in 47 commercial maize fields, which account for more than 400 ha in the Spanish provinces of Albacete, Badajoz and Madrid, to analyse the distribution of S. halepense as a function of various agricultural variables. The results showed significant effects of agricultural management on the presence of this weed. Crop rotation decreased the infestation of S. halepense. Furrow irrigation system favored the establishment of large patches with high plant density, while the sprinkler irrigation system favored the presence of isolated plants or small patches. Apparently, moldboard tillage promoted the establishment of large patches. The combination of different variables also had effects on the characteristics of the present infestations, and its management could lead to a better control in maize fields. 相似文献
453.
Perrin R Launois T Brogniez L Desbrosse FG Coomer RP Clegg PD Reda AA Gehin SG Vandeweerd JM 《Veterinary surgery : VS》2010,39(8):1030-1036
Objective: To assess the reliability of computed tomography (CT) to identify the direction of implant insertion for cortical screws along the longitudinal axis of intact (nonfractured) distal sesamoid bones. Study Design: In vitro study. Sample Population: Cadaveric paired equine forelimbs (n=16). Methods: Insertion of a cortical screw in lag fashion along the longitudinal axis of intact (nonfractured) distal sesamoid bones was evaluated in 2 groups (3.5 and 4.5 mm) of 8 paired limbs. In each group, the direction of the distal sesamoid bone was determined by CT (Equine XTC 3000 pQCT scanner). Screw placement was verified by specimen dissection. Implant direction was considered satisfactory if the entire screw length was within the distal sesamoid bone and not damaging the articular or flexural surfaces. Results: In our sample and according to our criteria, the proportion of satisfactory direction of screws was 0.63 (5/8) for 4.5 mm implants, and 0.87 (7/8) for 3.5 mm implants. Conclusions: CT is a useful imaging modality to identify anatomic landmarks for insertion of a 3.5 mm cortical screw in the distal sesamoid bone. 相似文献
454.
Impact of anthropogenic induced nitrogen input and liming on phosphorus leaching in forest soils 总被引:1,自引:0,他引:1
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Stefan Holzmann Anna Missong Heike Puhlmann Jan Siemens Roland Bol Erwin Klumpp Klaus von Wilpert 《植物养料与土壤学杂志》2016,179(4):443-453
Phosphorus (P) is essential for sustainable forest growth, yet the impact of anthropogenic impacts on P leaching losses from forest soils is hardly known. We conducted an irrigation experiment with 128 mesocosms from three forest sites representing a gradient of resin extractable P of the A‐horizon. On each site we selected a Fagus sylvatica and a Picea abies managed subsite. We simulated ambient rain (AR), anthropogenic nitrogen input (NI) of 100 kg (ha · a)?1 and forest liming (FL) with a dolomite input of 0.3 Mg (ha · a)?1. Soil solution was extracted from the organic layer, 10 cm depth and 20 cm depth of the mesocosms, and analyzed for molybdate reactive phosphorus (MRP) and molybdate unreactive phosphorus (MUP). Additionally, we separated colloids from the soil solution using Asymmetric Field Flow Fractionation for assessing the colloidal fraction of total element concentrations. NI increased MRP and MUP concentrations for all plots with one exception, while FL decreased MRP and MUP with the exception of another plot. While the irrigation treatments had little impact on the P‐richest site, MRP and MUP concentrations changed strongly at the poorer sites. The colloidal fraction of P in the soil solution equaled 38–47% of the total P load. Nitrogen input and liming also affected the Fe, Al, Ca, and Corg contents of the colloidal fraction. 相似文献
455.
456.
Heterosis and heritability in crosses among Asian and Ethiopian parents of hot pepper genotypes 总被引:1,自引:1,他引:0
Hot pepper is the most important worldwide grown and consumed spice and vegetable crop. Though hybrid breeding has been proposed
for genetic improvement in the crop, but there is lack of information on heterosis in crosses among crop genotypes in Ethiopia.
Twelve genotypes (nine Asian and three Ethiopian parents) of hot pepper were crossed in 2003 cropping season in a half-diallel
fashion to fit Griffing’s fixed effect model analysis. An open field experiment was conducted in 2004/2005 to investigate
heterosis for fourteen traits in 66 F1 hybrids grown together with their 12 selfed parents. Highly significant genotypic differences were observed for all the traits
except for leaf area. Variance component due to specific combining ability (dominance) were larger than that due to general
combining ability (additive) for each of the studied traits with few exceptions. Broad sense heritability (H
b2) for fruit traits were more than 60% and with wide gap from narrow sense heritability (h
n2) for most of the important traits like number of fruit per plant (H
b2 = 88.3% and h
n2 = 46.0%), days to maturity (H
b2 = 87.2% and h
n2 = 23.1%) and dry fruit yield per plant (H
b2 = 72.6% and h
n2 = 14.6%). Maximum heterosis over mid-parent and better-parent, and economic superiority of hybrid over standard check were
recorded, respectively for dry fruit yield per plant (163.8, 161.8 and 92.1%), number of fruits per plant (104.4, 79.6 and
136.4%) and days to maturity (−29.8, −31.5 and −23.6%). These observations suggested a possibility of utilizing dominance
genetic potentiality available in diverse genotypes of the crop by heterosis breeding for improving hot pepper to the extent
of better economic return compared to the current commercial cultivar under production in the country. Low narrow sense versus
very high broad sense heritability for days to maturity and dry fruit yield per plant could be a sign for achievability of
earliness and high fruit yield using heterosis in hot pepper. The maximum heterobeltiosis were recorded either from F1s obtained from Ethiopian and Asian crosses or from within Asian crosses, suggesting the possibility of maximizing heterosis
by considering genetically diverse parental genotypes. The manifestation of highest heterosis in hybrids from among Asian
lines indicated existence of genetic diversity among Asian genotypes and the potentiality for improvement of hot pepper using
genotypes from different regions of the world along with elite inbred lines from local cultivars. 相似文献
457.
Plant Foods for Human Nutrition - En conclusion, les orientations agronomiques à préconiser seraient celles-ci: 相似文献
458.
459.
OBJECTIVE: To define a 3-dimensional (3-D) coordinate system with clear definitions of origins and axes relative to hoof anatomic features and determine whether solar surfaces of Thoroughbred racehorse hooves have geometric asymmetry in the mediolateral and dorsopalmar directions. SAMPLE POPULATION: Left forelimb hooves from 20 Thoroughbred racehorse cadavers. PROCEDURE: A right-handed 3-D coordinate axes system centered on the collateral sulci was defined for the left front hoof. Orthogonal distances of anatomic features from the dorsopalmar axis and the plane coincident with the ground were measured and compared between medial and lateral sides and between dorsal and palmar regions of the hoof. RESULTS: The hoof was wider and had a greater radius laterally than medially. The most distal part of the lateral bar of the frog was further from the dorsopalmar axis than that of the medial bar. Overall, mediolateral asymmetries in depth were not observed. The sole at the perimeter was deeper medially in the dorsal part of the hoof and laterally in the palmar part, with depth overall being greater palmarly than dorsally. Most features had dorsopalmar asymmetry. CONCLUSIONS AND CLINICAL RELEVANCE: When the angle bisected by the collateral sulci is used to determine the dorsopalmar axis of the hoof, most central structures (bars and collateral sulci) have mediolateral symmetry. However, the hoof wall and sole have some mediolateral asymmetries and most structures have dorsopalmar asymmetry. These findings may assist the development of devices for attachment to hooves and studies of the interaction of hooves with bearing surfaces. 相似文献
460.
Aged laying hens at oviposition were given four levels of dietary vitamin D3 and three levels of 1,25-dihydroxyvitamin D3 (1,25[OH]2D3) to determine the effects of the additives on the medullary and endosteal bone. Oxytetracycline hydrochloride labeling and histomorphometry of undecalcified sections were used in the determination of changes in medullary bone and endosteal surface of mid-diaphyseal tibiotarsal bones. Treatment with 1,25(OH)2D3 increased mineralized medullary bone area, endosteal surface length, amount of tetracycline labeling in medullary and endosteal bone, total number of osteoclasts on endosteal and medullary bone, and appositional rate of mineralizing bone. Vitamin D3 increased mineralized medullary bone area and total tetracycline labeling in endosteal bone but decreased endosteal mineral apposition rate. Medullary bone matrix with no mineral was observed only in the group receiving neither supplement. These areas were much larger than typical osteoid seams usually seen in trabecular bone. Both 1,25(OH)2D3 and vitamin D3 were effective in stimulating bone formation and retention of mineral within medullary bone matrix at oviposition. 相似文献