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941.
Four snap bean varieties (green and yellow-podded) were grown in three water supplies (regularly irrigated, deficit-irrigated and non-irrigated) in order to examine the spectral reflectance at leaf and canopy levels, leaf area index (LAI) and their relationships with the yield and nutritional quality at the University of Debrecen, Debrecen, Hungary from 2011 to 2013. Under non-irrigated condition, the plant height decreased, SPAD values were high but LAI and normalized difference vegetation index (NDVI) were low. The difference in SPAD values was higher between the varieties during flowering under non-irrigated condition and it was more pronounced during pod development using deficit irrigation. In dry years, non-irrigated condition SPAD did not correlate with the yield but during pod development it was correlated with the dry matter content of the pods. The relationship of SPAD with protein and crude fiber content of pods was strongly dependent on the cropping years. Under deficit-irrigated condition, NDVI measured during flowering and pod development correlated closely with the yield where a higher NDVI (0.85) predicted either 6 or 9.5 t ha?1 of yield depending on the variety. Under this condition Serengeti variety with green pods was prominent based on the studied traits among the varieties.  相似文献   
942.
Precision agriculture provides important issues toward a more sustainable agriculture. Many farmers have the necessary technology to operate site-specifically, but they do not use it in practice, and thus available information and communications technology (ICT) systems are not used to their full potential. This paper addresses how to reduce the so-called “problem of implementation”, based on the knowledge that participatory approaches during the design and development process is one of the most important factors to frame technology adoption. The development of sustainable ICT systems through theories and methodologies from the fields of human computer interaction and user-centered design (UCD) is presented and an ongoing Swedish project for development of an agricultural decision support system (AgriDSS) for nitrogen fertilization is used as an example to frame the issue. The overreaching aim is to develop AgriDSSs that are sustainable in design as well as through design by stressing the importance of participatory approaches for the successful development of AgriDSSs. The Swedish project has the intention to apply a UCD approach, and some pitfalls on starting to use this way of working is identified as well as some suggestions on how to reduce them through co-learning processes. Despite the challenges presented in this paper, ICT can contribute significantly to long-term sustainable development. Thus, several competences and scientific disciplines need to act in concert to help develop a sustainable development of agriculture via a transdisciplinary approach that can make an impact on society at many levels.  相似文献   
943.
This paper describes the consequences of the ban on neonicotinoid seed treatments on pest management in oilseed rape. Since the ban was implemented in December 2013, there have been serious crop losses in 2014, 2015 and 2016 owing to cabbage stem flea beetles, Psylliodes chrysocephala, and aphids, Myzus persicae, which have developed resistance to the alternative pyrethroid sprays that were employed to control them. This has resulted in increased crop losses, decreased yields and a substantial decrease in the area grown, leading to fewer flowering crops available in the spring, especially in the eastern region of the United Kingdom. This is likely to have an adverse effect on bees locally. © 2016 Society of Chemical Industry  相似文献   
944.
Biological control is an important ecosystem service delivered by natural enemies. Together with breeding for plant defence, it constitutes one of the most promising alternatives to pesticides for controlling herbivores in sustainable crop production. Especially induced plant defences may be promising targets in plant breeding for resistance against arthropod pests. Because they are activated upon herbivore damage, costs are only incurred when defence is needed. Moreover, they can be more specific than constitutive defences. Nevertheless, inducible defence traits that are harming plant pest organisms may interfere with biological control agents, such as predators and parasitoids. Despite the vast fundamental knowledge on plant defence mechanisms and their effects on natural enemies, our understanding of the feasibility of combining biological control with induced plant defence in practice is relatively poor. In this review, we focus on arthropod pest control and present the most important features of biological control with natural enemies and of induced plant defence. Furthermore, we show potential synergies and conflicts among them and, finally, identify gaps and list opportunities for their combined use in crop protection. We suggest that breeders should focus on inducible resistance traits that are compatible with the natural enemies of arthropod pests, specifically traits that help communities of natural enemies to build up. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
945.
946.
Journal of Plant Diseases and Protection - Citrus black spot (CBS) is a disease caused by the fungus Phyllosticta citricarpa that is associated with significant yield losses. The pathogen forms...  相似文献   
947.
Journal of Plant Diseases and Protection - Avena fatua is one of the most abundant and competitive grass weed species in cereal cropping systems worldwide. Despite its main occurrence in summer...  相似文献   
948.
The pharmacokinetic profile, tolerability and efficacy of benzene‐poly‐carboxylic acids complex with cis‐diammineplatinum (II) dichloride (BP‐C1) were studied in dogs with mammary cancer. A three‐level response surface pathway designed trial was performed on seven dogs. At each level BP‐C1 was administered subcutaneously daily for 7 days followed by a 7‐day rest period in a dose escalating manner. Adverse events according to VCOG‐CTCAE, performance status and tumour progression were recorded. The pharmacokinetic profile followed a two‐compartment model with rapid absorption, short distribution, and a slow elimination phase. The overall elimination half‐life was 125 h. The maximum tolerated dose of BP‐C1 was estimated to be above 0.46 mg kg?1. A significant reduction in VCOG‐CTCAE toxicity which correlated negatively with increasing dose was found. The dogs' general performance status remained unchanged. No decrease in total tumour burden was found, although temporary tumour reduction was seen in some target tumours.  相似文献   
949.
950.
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