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81.
Sesamia nonagrioides Lef. and Ostrinia nubilalis (Hübn.) are two corn borers present in the Mediterranean area that share a similar feeding habitat. The female sex pheromones of the two species consist of (Z)-11-hexadecenyl acetate, (Z)-11-hexadecen-1-ol, (Z)-11-hexadecenal and dodecyl acetate (77:8:10:5 w/w) and (Z)-11-tetradecenyl acetate and (E)-11-tetradecenyl acetate (97:3 w/w) respectively. Although the pheromones share no common components, previous work had shown the inhibition of the response by O. nubilalis males to their own pheromone owing to the presence of S. nonagrioides pheromone. In this study, the pheromone of O. nubilalis and its two components separately were shown to inhibit the attraction of S. nonagrioides males to the synthetic female pheromone in both laboratory wind-tunnel bioassay and field trapping studies. In the wind tunnel, the number of contacts of S. nonagrioides males with the source were significantly (P < 0.05) reduced by the single pheromone components of O. nubilalis. In the field, the addition of 1% of O. nubilalis pheromone significantly (P < 0.05) reduced the catches of S. nonagrioides males. The components of both pheromones also elicited electroantennographic responses from antennae of male S. nonagrioides moths. The ecological consequences and the possibilities of applying this cross-inhibition for mating disruption techniques are discussed.  相似文献   
82.
Zusammenfassung Durch Anwendung des TTC-Schnelltestes wurde versucht, ein praktisch brauchbares Keimprüfungsverfahren für Kaffeesamen zu entwickeln. Es wird eine Routinemethode zur Keimprüfung mit TTC vorgeschlagen, die mit isolierten Embryonen von Kaffee arbeitet. Dieses Verfahren wurde an 4 verschiedenen Samenproben von Kaffee überprüft. Die Übereinstimmung der Ergebnisse aus den Keimprüfungen, die vergleichend unter natürlichen Bedingungen vorgenommen wurden, mit denen des TTC-Testes war gut, so daß eine praktische Anwendung des Verfahrens für den Kaffeeanbau gerechtfertigt erscheint.
Application of triphenyltetrazolium chloride for rapid testing of the viability of seeds fromCoffea arabica L.
Summary Using TTC we tried to develop a useful method for testing the germination capability of coffee seeds. A routine test method for germination using TTC is suggested, which works with isolated embryos of the coffee seeds. This method was tested with 4 different samples of coffee seeds and compared with the germination of coffee seeds at natural conditions. The agreement of the results from both germination tests was very good. Therefore the application of the test with TTC is proposed for the practical coffee farming.

-- Coffea arabica L.
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Despite the fact that the use of rosemary and thyme residues and essential oils in animal feeding was widely documented, that of myrtle is scarce. To test the hypothesis that myrtle essential oils (MEOs) could improve goats' carcass characteristics and meat quality traits, twenty-one male goats received a ration consisted of 40% oat hay and 60% concentrate. Experimental goat kids received the control diet supplemented with 0, 0.3 and 0.6% of myrtle essential oils (MEOs) for C, Myrt1 and Myrt2 groups respectively. The administration of MEO did not improve the daily DM intake (p > 0.05). Kids of C and Myrt2 groups had higher average daily gain than Myrt1 group (75 versus 55 g). The goats slaughtered at 19.9 kg of weight did not differ (p > 0.05) in carcass weights and carcass yield in terms of commercial dressing percentage (CDP = 41%) and real dressing percentage (RDP = 52%). The administration of MEO increased the meat polyphenol content, being higher in both Myrtle groups (87 versus. 56 μg gallic acid equivalents g-1 fresh matter, p < 0.05). Myrtle EO administration protected kids’ meat against oxidation (0.48 versus. 0.91 mg MDA/kg of meat for Myrtle and C groups, respectively, at the 9th day of storage; p < 0.05). It could be useful to include MEO as a dietary supplement in goats’ rations since it improves meat's oxidative status without negative effects on FA profile.  相似文献   
87.
A Review of Combine Sensors for Precision Farming   总被引:9,自引:0,他引:9  
Reyns  P.  Missotten  B.  Ramon  H.  De Baerdemaeker  J. 《Precision Agriculture》2002,3(2):169-182
To maximize economic return from agricultural production units, costs have to be minimized and benefits maximized. For grain, kernel yield and quality have to be maximized while the use of seeds, fertilizer, herbicides and fungicides have to be optimized.The best location to evaluate productivity levels, by measuring yield and quality of grain and straw, is the combine harvester. Moreover, other grain quality characteristics like density or test weight can be determined for use as an evaluation tool. In this paper, an overview is given of the past and current research toward the evaluation of currently available commercial sensors (e.g., for measuring grain yield and grain moisture content) as well as toward the development of new sensors (e.g., grain protein content and straw yield).  相似文献   
88.

Purpose

The impact of agriculture on water resources has long been a problem associated with the formation of runoff, the siltation of lakes and reservoirs, and overall depletion of water quality. In Brazil, these problems are mainly related to soil degradation by water erosion. However, studies of catchment-scale erosion are still rare particularly in grain-producing regions which have adopted conservative tillage systems for soil protection. In order to contribute to a better understanding of the impact of conservation agriculture on water resources, this study determined the runoff coefficient and sediment yield for two agricultural catchments.

Materials and methods

Hydrological and sedimentological monitoring was conducted in two catchments: the Conceicao catchment is characterized by grain production in weathered soils and a gently sloping landscape, while the Guapore catchment is characterized by heterogeneous soils and topography. Both catchments have problems associated with water erosion.

Results and discussion

The magnitudes of annual runoff coefficients and sediment yield were high, even if compared to similar agricultural regions, including a catchment with widespread adoption of no-tillage. The sediment yield was 140 t km?2 year?1, and the runoff coefficient was 14 % for the Conceicao catchment, while the sediment yield was 270 t km?2 year?1, and the runoff coefficient was 31 % for the Guapore catchment. The results indicate that problems such as gullies, soil compaction, runoff, floods, siltation, and water quality depletion associated with the misuse of agricultural areas in terms of soil conservation and water use are still evident and important even in regions with widespread adoption of no-tillage systems.

Conclusions

The magnitudes of both runoff and sediment yield clearly indicate the need to adopt complementary practices of soil conservation measures, such as mechanical runoff control.  相似文献   
89.
Tropical Animal Health and Production - The objective of this study was to assess aspects of the social behavior of a mixed-breed herd of beef cows as a potential source for stress and economic...  相似文献   
90.

Introduction   

This article explores the possibility of including multiple spatial scales into a mixed model for predicting the density of human-caused fire ignitions in Catalonia (North-East Spain).  相似文献   
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