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51.
The aim of this study was to analyse the soil compaction and its spatial variability on an alluvial plain in K?z?l?rmak River Delta in Turkey, which is an important agricultural area where vegetable, rice, cereals and other crops have been grown under conventional tillage and irrigation over a long period. Penetration resistance (PR) was measured at 5 cm depth intervals between 0 and 40 cm soil depth, and gravimetric water content (GWC), field capacity (FC) and texture were determined for 0–20 cm and 20–40 cm. Penetration resistance values in some parts of the area were higher than the critical value for root growth limitation, the mean PR values at all depths were considerably lower than the critical value despite a relative increase in PR with soil depth. The areas with values greater than 3.0 MPa, except for 0–5 cm, were generally located in the fields with high sand content, especially near the K?z?l?rmak River. In contrast, for 0–5 cm, the areas with PR greater than 3.0 MPa, which is the value accepted for root growth limitation, were usually located in the west and northwest of the study area and had a high clay content.  相似文献   
52.
The incidence of Alfalfa mosaic virus (AMV), Potato leafroll virus (PLRV), and Potato virus Y (PVY) in potato crops derived from various types of seed potatoes was assessed visually and confirmed by direct tissue blot immunoassay, over two winter growing seasons (1999/2000, 2000/2001) at three locations, Elnaiya, Elshehinab, and Shambat in Khartoum State, the main potato growing region in Sudan. Virus infection was most prevalent in 2000/2001. In general, crops grown directly from imported certified seed potatoes and from “improved seed”, produced in Sudan from imported basic seed, showed the lowest levels of PLRV and PVY compared with crops grown from Sudanese farm saved seed. For AMV, however, only crops grown directly from imported certified seed potatoes had low levels of AMV. Crop location also affected virus incidence, although this varied with year. For AMV, levels were similar at all locations in 1999/2000, but were greatest at Elnaiya in 2000/2001. For PVY, levels were greatest at Elnaiya in 1999/2000 and Shambat in 2000/2001. For PLRV, no symptoms were observed in 1999/2000 and virus levels were similar for all locations in 2000/2001. This study reports for the first time the occurrence of AMV in potatoes grown in Sudan.  相似文献   
53.
<正>印度尼西亚是世界上岛屿最多的国家,由Java、Sumatra、Sulawesi、Kalimantan和IrianJaya等5个较大的岛屿组成。辣椒是印度尼西亚人的重要蔬菜和调味佳品,咖喱饭调味品是最具特色的辣椒制品。  相似文献   
54.
The bulb onion (Allium cepa L.) has been cultivated for thousands of years and used as an important component of human diet. Recent studies suggest that onions can be used to cure, reduce, or prevent some of the health problems such as cancer, cardiovascular diseases, antidiabetic, asthma, antibiosis, and prebiotic effects due to its high antioxidant effect. In this study, we determined the antioxidant capacities of a wide range of onion cultivars; nine commercial cultivars and five advance selections differing in color. The variables tested include bulb size, scale color, total phenolic (TP), total antioxidant activity determined by both “Ferric reducing ability of plasma” (FRAP) and “Trolox equivalent antioxidant capacity” (TEAC). We found that yellow onion had the greatest TP content (3.7 mg GAE/g dw); and, the red group had higher TP mean than the white group (2.2 mg GAE/g dw vs. 1.1 mg GAE/g dw). For the antioxidant capacity measurements, the red group had the greatest means by both methods (15.4 μmol TE/g dw and 9.3 μmol TE/g dw for TEAC and FRAP). Yellow onions had higher TEAC (14.7 μmol TE/g dw vs. 8.7 μmol TE/g dw) and FRAP values (9.8 μmol TE/g dw vs. 5.6 μmol TE/g dw) than white onions. Among the cultivars tested great differences of TP, TEAC and FRAP was observed. The TP content of Me-Tan 88 (8.3 mg GAE/g dw) was two times higher than the yellow group. Yellow color Dayton had the greatest TEAC (20.5 μmol TE/g dw) and FRAP (12.3 μmol TE/g dw) means followed by yellow color Me-Tan 88 (19.4 and 11.4 μmol TE/g dw). The two antioxidant measurements were found to be highly correlated (0.99) where absolute values of FRAP were about 40% less than those of TEAC. The values of TEAC and FRAP were significantly correlated by TP with similar rs (0.74 and 0.73, respectively). TP, TEAC and FRAP were significantly and positively correlated to soluble solids (0.41, 0.43, and 0.40, respectively). Our results suggested that the red onions had higher antioxidant activities than yellow and white onions although yellow onions had the richest phenolic contents.  相似文献   
55.
The effect of high temperature on survival and longevity of Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) female adults was studied in the laboratory by daily exposure of the beetles to 35°C (mean r.h. 52%) combined with 1-, 2- and 3-h intervals of thermal treatment at 38, 40, 42 and 44°C (r.h. 46–48%). Fifty percent of females survived until the 12th–13th day of the thermal treatment at 38°C (depending on the exposure time), the 2nd–10th day at 40°C for 1–2 h exposure and the 4th–5th day at 42°C for 1 h exposure. Survival was 25–38% on the 1st–2nd day of the thermal treatment at 40, 42 and 44°C for 3, 2 and 1 h of exposure, respectively. Three hours of exposure of female C. montrouzieri at 42°C and 2 h exposure at 44°C were lethal for the beetles. Mean longevity of the predator was 33.13?±?1.22 days at 35°C and was significantly shorter as the temperature of the thermal treatments increased from 38o to 44°C. These results suggest that daily temperature regimes of 35°C combined with 38–40°C for 1–3 h are marginal for the survival and longevity of the C. montrouzieri, whereas temperatures above 42°C are lethal even at short exposure. These results can partly justify the inability of C. montrouzieri to be permanently established in Pakistan environments and could contribute to a pre-evaluation assay of its potential adaptability in such environmental systems.  相似文献   
56.
Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage (CT) is more productive than zero tillage (ZT)/reduced tillage (RT). Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC (108 g a.i. ha-1), lactofen 24 EC (168 g a.i. ha-1), haloxyfop 10.8 EC + lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I.Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop + lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides×CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides×CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I.Khan.  相似文献   
57.
Protein efficiency ratio (PER), relative PER (RPER), net protein ratio (NPR) and relative NPR (RNPR) values, and amino acid scores were calculated for 20 food products (casein, casein + Met, beef salami, skim milk, tuna, chicken frankfurters, sausage, heated skim milk, peanut butter, rolled oats, soy isolate, chick peas, pea concentrate, kidney beans, wheat cereal, pinto bean, lentils, rice-wheat gluten cereal, macaroni-cheese, and beef stew). In most cases, PER, RPER, NPR or RNPR ranked the products in the same order and positive correlations among the protein quality methods were highly significant (r=0.98–0.99). Amino acid scores (based on the first limiting amino acid, Lys-Met-Cys, Lys-Met-Cys-Trp or lys-Met-Cys-Trp-Thr) were positively correlated to the PER, RPER, NPR or RNPR data (r=0.61–0.75). Inclusion of the correction for true digestibility of protein improved the correlations between amino acid scores and the indices based on rat growth. The correlations were especially high between Lys-Met-Cys scores (corrected for true digestibility of protein) and PER, RPER, NPR or RNPR (r=0.86–0.91). Inclusion of the correction for true digestibility of individual amino acids did not result in further improvements of the correlations in most cases. It is concluded that adjusting amino acid scores for true digestibility of protein would be sufficient and further correction for digestibility of amino acids would be unnecessary in mixed diets.This paper was presented in part at the 71st annual FASAB meeting, Washington, DC, March 29–April 2, 1987.  相似文献   
58.
59.
The effects of vitamin E and vitamin E-selenium combination on seminal plasma arginase activity and nitric oxide level and some spermatological properties in rams were investigated in this study. For control group, animals were injected intramuscularly with physiological saline. For vitamin E group, rams were injected intramuscularly with 300 mg/ram vitamin E. For vitamin E + selenium group, animals were injected intramuscularly with 5 ml/ram vitamin E + selenium. The semen was collected by artificial vagina at 1st, 4th, 24th, 48th and 72nd hr after administration in each group. Significant decreases in seminal plasma arginase activity (at 1st, 24th and 48th hr), nitric oxide level (at 72nd hr) and abnormal sperm rate (at 1st, 24th and 72nd hr), and significant increases in semen volume (at 24th hr), semen mass activity (at 24th and 48th hr), sperm motility (at 24th, 48th and 72nd hr) and concentration (at 1st hr) were observed in vitamin E group compared with control group. Similarly, significant increase in semen volume (at 1st, 24th and 48th hr), mass activity, (at 48th hr), motility (at 48th and 72nd hr) and concentration (at 4th, 24th and 48th hr), and significant decrements in abnormal sperm rate (at 1st, 24th, 48th and 72nd hr), seminal plasma nitric oxide level (at 1st, 4th, 24th and 48th hr) and semen pH (at 24th and 48th hr) were detected in vitamin E + selenium group in comparison to the control group. As a result, it is suggested that vitamin E and/or vitamin E + selenium applications may improve reproductive performance.  相似文献   
60.
Tropical Animal Health and Production - This study examined the analysis of personal and production performance of broiler farming in 10 cities of central Punjab (Lahore, Sheikhupura, Kasur, Okara,...  相似文献   
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