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211.
Precision agriculture is a farming management concept based on observing, measuring and responding to inter- and intra-field variability in crops. In this paper, we focus on responding to intra-field variability in potato crops and analyse variable rate applications (VRAs). We made an overview of potential VRAs in potato crop management in The Netherlands. We identified 13 potential VRAs in potato, ranging from soil tillage to planting to crop care to selective harvest. We ranked them on availability of ‘proof of concept’ and on-farm test results. For five VRAs, we found test results allowing to make a cost-benefit assessment. These five VRAs were as follows: planting, soil herbicide weed control, N side dress, late blight control and haulm killing. They use one of two types of spatial data: soil maps or biomass index maps. Data on costs and savings of the VRAs showed that the investments in VRAs will pay off under practical conditions in The Netherlands. Savings on pesticide use and N-fertilizer use with the VRAs were on average about 25%, which benefits the environment too. We foresee a slow but gradual adoption of VRAs in potato production. More VRAs will become available given ongoing R&D. The perspectives of VRAs in potatoes are discussed.  相似文献   
212.
This paper surveys issues and developments emerging from the keynotes and participants’ presentations during the 20th EAPR Triennial Conference, held in Versailles, France, in July 2017, and puts them into the perspective of the general theme of the meeting: potato facing global challenges. It reveals important and far-reaching innovations in many areas of potato research, including breeding (genomic selection, high-throughput phenotyping, genome editing), plant protection (biocontrol) and seed production, but also a general innovation approach that follows an incremental pathway (and maintains many existing lock-in situations), and favours substitution strategies over system re-conceptualisation and testing, however urgently needed these might be to achieve or improve the sustainability of potato production in the medium to long run. While the assets and importance of potato as both a wholesome food and an essential part of future worldwide food systems were once more evidenced and highlighted, the contributions also revealed (i) a growing dichotomy between research activities carried out in high-income vs in low- or moderate-income countries, respectively; (ii) some gaps in the assessment of the sustainability of potato production in the medium to long run (external inputs such as fertilisers or pesticides, land and energy use efficiency); and (iii) persistent weaknesses in the integration of individual solutions into complete, operational potato production systems. Some areas for future investigations are identified.  相似文献   
213.
CRISPR-Cas technology has raised considerable interest among plant scientists, both in basic science and in plant breeding. Presently, the generation of random mutations at a predetermined site of the genome is well mastered, just like the targeted insertion of transgenes, although both remain restricted to species or genotypes amenable for plant transformation. On the other hand, true genome editing, i.e. the deliberate replacement of one or several nucleotides of the genome in a predetermined fashion, is limited to some rather particular examples that generally concern genes allowing positive selection, for example tolerance to herbicides. Therefore, further technological developments are necessary to fully exploit the potential of genome editing in enlarging the gene pool beyond the natural variability available in a given species. In principle, the technology can be applied to any quality related, agronomical or ecological trait, under the condition of upstream knowledge on the genes to be targeted and the precise modifications necessary to improve alleles. Published proof of concepts concern a wide range of agronomical traits, the most frequent being disease resistance, herbicide tolerance and the biochemical composition of harvested products. The regulatory status of the plants obtained by CRISPR-Cas technology raises numerous questions, in particular with regard to the plants that carry in their genomes the punctual modifications caused by the presence of the Cas9 nuclease but not the nuclease itself. Without clarification by the competent authorities, CRISPR-Cas technology would continue to be a powerful tool in functional genomics, but its potential in plant breeding would remain untapped.  相似文献   
214.
Global challenges like sustainable development, climate change, malnutrition and gender inequality can be tackled from an agricultural perspective. Micronutrient deficiency is a major problem for the health and food security of the population. In Colombia, iron deficiencies affect 32% of the children under the age of five; and 43% of the Colombian population have zinc and vitamin A deficiencies. We designed and implemented a research-for-development programme that links agriculture and nutrition through a two-stage project. In the first stage, we selected three new yellow potato cultivars with better nutritional contents, higher yield and better resistance to late blight than the traditional yellow cultivars. We characterized the Colombian germplasm, Solanum tuberosum Group Phureja, for its nutritional attributes. During this stage, studies of the social and nutritional status of the communities were also conducted. In the second stage, we focused on scaling up new potato cultivars to reach potato producers and consumers by promoting the production and marketing of good quality seed potatoes, by establishing four Rural Entrepreneurs Nuclei. The programme promotes gender equity, good dietary habits, the consumption of more nutritious potatoes and empowers local leadership to strengthen governance. Field work was conducted in southern and central regions of Colombia by employing social strategies such as the Family Farming Community Schools. In 50% of the cultivated area, we are replacing the originally used traditional yellow potatoes by the new, more nutritious, potatoes to reach 6 million consumers. A good quality seed system for small-scale potato growers has been implemented. These achievements have been reached through a comprehensive approach in a period of two years.  相似文献   
215.
This research aims to make an analysis of energy use efficiency of apple (‘Starkrimson Delicious’ and ‘Golden Delicious’) production in E?irdir region of Turkey, during the production season of 2012. Production data this research was collected in 2013. In order to determine the energy use efficiency of apple, various surveys have been conducted in 71 apple farms, selected through Simple Random Sampling method, located in E?irdir region of Turkey. The data have been collected through face to face questionnaires and first hand observations. The energy input and output values in apple production have been calculated as 34,703.63 MJ ha?1 and 95,034 MJ ha?1, respectively. Energy inputs consist of diesel fuel energy by 29.04?%, chemical fertilizers energy by 24.28?%, machinery energy by 15.70?%, chemical energy by 9.84?%, human labor energy by 8.54?%, electricity energy by 5.63?%, irrigation energy by 3.97?%, farmyard manure energy by 2.88?% and lime energy by 0.12?%. Energy use efficiency, energy productivity, specific energy and net energy in apple production have been calculated as 2.74, 1.16 kg MJ?1, 0.86 MJ kg?1 and 60,330.36 MJ ha?1, respectively. The total energy input consumed has been classified as direct, by 47.17?%, indirect, by 52.83?%, renewable, by 15.38?% and non-renewable, by 74.62?%.  相似文献   
216.
This research was conducted to determine the changes in the seasonal carbohydrates of annual shoots and growth characteristics of 10 years old ‘Trakya ?lkeren’ grape variety. Grapevines are grafted on 5BB and 5C rootstocks and they were grown in heavy clay soil conditions. In the study, changes of sugar, starch and total carbohydrates were determined from bud burst to dormancy. While sugar, starch and total carbohydrates showed significant differences (P < 0.01) there were no differences between rootstocks. Although sugar, starch and total carbohydrates of shoots decreased from bud burst to blooming, they increased thereafter until vegetative growth stopped. Total carbohydrates of annual shoots have been found to accumulate in period from blooming to harvest. Total and mean leaf area, shoot length and diameter, total chlorophyll and chlorophyll a/b ratio showed significantly variation among rootstocks and phenological stages (P < 0.01). Whereas the highest chlorophyll contents were found in the blooming, it was found at the lowest through to harvest. Overall mean and total leaf area, shoot length and shoot diameter, total chlorophyll content and chlorophyll a/b ratio were significantly higher on 5BB grafted vines. In the study, 5BB rootstocks are found suitable in terms of shoot carbohydrate accumulation and growth characteristics for ‘Trakya ?lkeren’ grape variety.  相似文献   
217.
This study was carried out in ?scehisar district of Afyonkarahisar on ‘0900-Ziraat’ sweet cherry cultivar for two successive years in 2011 and 2012. Ten different applications consisting of 80?g FeSO4.7H2O tree?1, 20?g FeEDDHA tree?1, 420?mL TK?-Hümas tree?1, 80?g FeSO4.7H2O + 420?mL TK?-Hümas tree?1, 200?g powder sulphur (S) tree?1, 80?g FeSO4.7H2O + 200?g powder S tree?1, 25?g ZnSO4.7H2O tree?1, 25?g ZnSO4.7H2O + 420?mL TK?-Hümas tree?1 and 25?g ZnSO4.7H2O + 200?g powder S tree?1 were subjected for determination of their effect on vegetative growth of sweet cherry. In this study, shoot diameter, shoot length, leaf total chlorophyll content, leaf area and leaf iron (Fe) and zinc (Zn) contents were obtained. Shoot length, shoot diameter and leaf area showed general increases in 80?g FeSO4.7H2O + 200?g powder S tree?1 and 25?g ZnSO4.7H2O + 200?g powder S tree?1 treatments.The results clearly indicated that he treatments had different effects on the shoot length and shoot diameter although there was a differences between the experimental years. Particularly, significantly positive effects of the treatments on leaf total chlorophyll was apparent for the second year’s observations. In addition, Fe and Zn concentrations in leaf were markedly increased in response to the treatments.  相似文献   
218.
Yield management is important subject in modern grape growing and winter pruning and cluster thinning treatments were used for yield control. Standard cluster thinning is generally labor intensive and expensive method and grape growers try to new methods, which are alternative to cluster thinning for reducing berry set. The goal of the present research was to investigate the effects of chemical thinning treatments such as ethephon (ETH), gibberellic acid (GA3), naphthalene acetic acid (NAA) and non-chemical thinning treatments such as early leaf removal (ELR) and standard cluster thinning (SCT) on decreasing grape yield and enhancing berry composition of cv. Shiraz. In this study, percentages of berry set of cv. Shiraz were decreased by both chemical and non-chemical thinning treatments compared to Control. The results from these two different thinning methods shown certainly significant differences in berry composition of cv. Shiraz. Eventually, the best results in improved quality characteristics of cv. Shiraz were obtained from ELR treatment and treatments of ELR, ETH, GA3, NAA and SCT successively resulted in considerable enhancements in quality attributes of cv. Shiraz.  相似文献   
219.
The aim of this research is to compose the energy input-output analysis of plum in Nevsehir province in Turkey. This research was conducted at the plum cultivating facilities during the 2015–2016 production seasons in Nevsehir province of Central Anatolian Region in Turkey. The agricultural input energies and output energies used in plum cultivation were calculated to determine the energy input-output analysis. According to the research findings, the energy inputs in plum cultivation were calculated respectively 3920?MJ ha?1 (44.99%) chemical fertilizers energy, 1618.91?MJ ha?1 (18.58%) diesel fuel energy, 1125.85?MJ ha?1 (12.92%) chemicals energy, 1069.20?MJ ha?1 (12.27%) machinery energy, 723.24?MJ ha?1 (8.30%) human labour energy and 255?MJ ha?1 (2.93%) irrigation water energy. Production output plum yield were calculated as 12,112.50?MJ ha?1. The energy output/input ratio, specific energy, energy usage efficiency and net energy calculations were calculated respectively as 1.39, 1.37?MJ kg?1, 0.73?kg MJ?1 and 3400.30?MJ ha?1.  相似文献   
220.

Context

Habitat loss, fragmentation and degradation are widespread drivers of biodiversity decline. Understanding how habitat quality interacts with landscape context, and how they jointly affect species in human-modified landscapes, is of great importance for informing conservation and management.

Objectives

We used a whole-ecosystem manipulation experiment in the Brazilian Amazon to investigate the relative roles of local and landscape attributes in affecting bat assemblages at an interior-edge-matrix disturbance gradient.

Methods

We surveyed bats in 39 sites, comprising continuous forest (CF), fragments, forest edges and intervening secondary regrowth. For each site, we assessed vegetation structure (local-scale variable) and, for five focal scales, quantified habitat amount and four landscape configuration metrics.

Results

Smaller fragments, edges and regrowth sites had fewer species and higher levels of dominance than CF. Regardless of the landscape scale analysed, species richness and evenness were mostly related to the amount of forest cover. Vegetation structure and configurational metrics were important predictors of abundance, whereby the magnitude and direction of response to configurational metrics were scale-dependent. Responses were ensemble-specific with local-scale vegetation structure being more important for frugivorous than for gleaning animalivorous bats.

Conclusions

Our study indicates that scale-sensitive measures of landscape structure are needed for a more comprehensive understanding of the effects of fragmentation on tropical biota. Although forest fragments and regrowth habitats can be of conservation significance for tropical bats our results further emphasize that primary forest is of irreplaceable value, underlining that their conservation can only be achieved by the preservation of large expanses of pristine habitat.
  相似文献   
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