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Förlängt kalvningsintervall
Get PDFSvenska mjölkkors mjölkavkastning ökar för varje år som går. Ett kalvningsintervall om 12–12,5 månader är vanligt och har varit rekommendationen de senaste 30 åren för att uppnå en maximal vinst då försök visat att mjölkavkastningen sjunker ju längre laktationen går. Samtidigt visar flera studier på att sjukdomsförekomsten är som störst just kring kalvning, att fruktsamheten förbättras vid förlängt kalvningsintervall och att det inte stämmer att mjölkavkastningen skulle minska vid en förlängd laktation.
Syftet med denna studie är därför att ta reda på om rekommendationerna om ett kalvningsintervall om 12–12,5 månader fortfarande är det mest lönsamma. Detta genomförs genom att granska och räkna på data ifrån ett försök på 226 kors första laktation med randomiserat traditionellt och förlängt kalvningsintervall och beräkna de kostnader och intäkter som varierar dem emellan. Försöket genomfördes mellan den 23 augusti 2018 – 27 september 2020. För att avgränsa arbetet så kommer bland annat olika rasers påverkan inte tas i beaktan och endast konventionella priser kommer att användas.
Resultatet från studien visar på att medelavkastningen för förstakalvare inte sjunker om den förlängs från 12,3 till 15,4 månader. Intäkterna visade ingen signifikant skillnad men det gjorde däremot kostnaderna där korna för det förlängda kalvningsintervallet var i genomsnitt 2 kronor billigare per dag. Ett förlängt kalvningsintervall medförde en bättre fruktsamhet vilket innebar färre semineringar och ett kortare intervall mellan första och sista seminering. Intäkterna för slaktkor minskade samtidigt som kostnaderna för rekryteringskvigor också minskade.
Resultatet visar att ett traditionellt kalvningsintervall om 12–12,5 månader inte behöver vara det mest lönsamma för förstakalvare och att en strategi om individuella laktationslängder skulle kunna vara gynnsamt. Strategier om kalvningsintervallets längd bör fattas med stor omsorg då det påverkar dynamiken av djurflöden och kan påverka lönsamheten.The average milk yield of Swedish dairy cows increases by each year. A calving interval of 12-12.5 months is common and has been the recommendation for the past 30 years to achieve a maximum gain as studies have shown that the milk yield decreases every day past 60 days in milk. At the same time, several studies show that the incidence of disease is greatest around calving, that fertility improves with an extended calving interval and that the daily milk yield won´t decrease if the calving interval becomes longer.
The purpose of this study is therefore to find out whether the recommendations for a calving interval of 12–12.5 months still is the most profitable. This is done by reviewing and calculating data of 226 primiparous cows first lactation with a randomized short and long calving interval and calculating the costs and revenues that vary. The experiment was done between 23 August 2018 - 27 September 2020. To limit the work, the impact of different breeds will not be considered and only prices of conventional dairy production will be used.
The results from the study show that the average yield of primiparous cows does not decrease if it is extended from 12.3 to 15.4 months. The income did not show a significant difference, but the costs did, where the cows for the extended calving interval were on average 2 SEK cheaper per day. An extended calving interval resulted in better fertility, which meant fewer inseminations and a shorter interval between the first and last insemination. Revenues for slaughter cows decreased at the same time as the costs for replacement heifers also decreased.
The results show that a calving interval as short as 12–12.5 months doesn’t have to be the most profitable for primiparous cows and that a strategy of individual lactation lengths could be favourable. Strategies about the length of the calving interval should be taken with careful consideration as it affects the dynamics of replacement and can affect the profitability
The Use of Hoverflies as Multi -Tool for Pollination and Biological Control of Aphids and Grey Mould
Get PDFThe ascomycete Botrytis cinerea is a major pathogen in strawberry (Fragaria x ananassa) and causes enormous fruit losses if not controlled. In biological control, microbes such as the yeast Metschnikowia fructicola are sprayed on the flowering crops to alleviate the infestation. Besides spraying, biological control agents can be applied by entomovectoring which is established for bumble or honey bees. In this study, the aphidophagous hoverfly species Eupeodes corollae was tested as a vector for M. fructicola. First, the antagonistic effect of M. fructicola to B. cinerea was evaluated in a dual culture test. Then, the capacity of adult E. corollae to vector M. fructicola cells was examined In vitro and In vivo towards strawberry flowers. The efficiency of yeast dispersal was compared to spray application of M. fructicola on the flower. The final aim was to survey whether the application of M. fructicola by fly-vectoring on flowers decreased B. cinerea severity on developing fruits in comparison to spray application of M. fructicola. The results showed an inhibitory effect of M. fructicola (UDA 10) on B. cinerea (B05.10) in a dual culture. In vitro, the yeast was vectored by E. corollae. In vivo, E. corollae vectored M. fructicola cells to the flowers. In a small-scaled preliminary experiment, yeast cells vectored by hoverflies to the flower could not reduce the grey mould severity on later strawberry fruits kept in cold storage. This was the first attempt to explore the potential of the hoverfly species for the entomovector technology. Further research is needed to survey if E. corollae can complement existing entomovectoring systems, and if the hoverfly-vectoring can be an alternative to spray application of fungicides. Confirmation that E. corollae is an efficient vector of yeast to suppress grey mould, the hoverfly species could be used as a multitool in strawberry production combining biological control of aphids, grey mould, as well as pollination services
Smittspridning och förebyggande åtgärder för East Coast Fever
Get PDFEast Coast Fever orsakas av den encelliga parasiten Theileria parva och är en av de viktigaste sjukdomarna hos nötkreatur i Afrika då många djur smittas och dör genom kliniska symptom. Utöver att sjukdomen är plågsam påverkas även djurvälfärden negativt. Lantbrukare drabbas även ekonomiskt, både på grund av de förebyggande åtgärder som görs samt genom förlusten av djur. Parasiten som sprids via fästingen Rhipicephalus appendiculatus till nötkreatur har även den vilda afrikanska buffeln som värddjur. Bufflarna drabbas dock inte av samma allvarliga kliniska symptom som boskapen. På många platser betar boskap och afrikanska bufflar på delade betesmarker vilket kan öka sannolikheten att boskap utsätts för smitta och interaktionen har visat sig ha en betydande roll för smittspridning av ECF. R. appendiculatus trivs i specifika abiotiska förhållanden, där luftfuktighet-, temperatur-, latitud- och säsongsvariationer spelar en viktig roll för fästingens möjlighet att utvecklas. Förhållanden som påverkar fästingen är bland annat regnsäsong då aktiviteten hos den icke färdigutvecklade fästingen ökar samt luftfuktighet som påverkar fästingens utvecklingsfas. Genom kunskap och förståelse för hur R. appendiculatus påverkas under olika förhållanden, samt hur T. parva sprider sig mellan sina värddjur, kan olika förebyggande åtgärder användas för att minska spridning av ECF. Åtgärder som kan vara effektiva är betesplanering vid delade betesmarker samt behandling med acaricider på boskapen.East Coast Fever is caused by the obligate intracellular parasite Theileria parva and is one of the most important diseases for cattle in Africa as many animals becomes infected and dies from clinical symptoms. In addition to the disease being painful, animal welfare is also negatively affected. At the same time, farmers are affected economically, both due to the preventive measures and through the loss of animals. The parasite, which spreads through the tick Rhipicephalus appendiculatus to cattle, has the wild African buffalo as its host animal as well. However, the buffaloes do not suffer from the same serious clinical symptoms as cattle. In many places, livestock and African buffalos graze on shared pastures. This can increase the likelihood of livestock being exposed to infection as the interaction has been shown to play a significant role in the spread of ECF. R. appendiculatus thrives in specific abiotic conditions, where humidity, temperature, latitude and seasonal variations play an important role in the tick's ability to develop. Conditions like wet season affect the undeveloped tick’s activity, whereas humidity is important for the tick's development phase. Through knowledge and understanding of how R. appendiculatus is affected under different conditions, together with how T. parva spreads between its host animals, various preventive measures can be used to reduce the spread of ECF. Measures that can be effective are pasture planning on shared pastures and treatment with acaricides on livestock
Design for green structures in densifying hospital areas : a design proposal for Skåne University Hospital Malmö
Get PDFSkåne University Hospital Malmö has been
going through a process of densification for
over 120 years. The original planning of the
institution from 1896 was characterised
by a castle-like building located in a park
environment. Due to the growing city of
Malmö the hospital has been forced to adjust
and expand. Densification of the hospital area
has led to an extensive loss of green space,
left are fragments of the former park. The
main objective of this research is to make a
design proposal for SUS Malmö. The aim is
to explore how design can be used as a tool to
create resilient green structures in densifying
hospital areas. The following questions guide
the research: How to design resilient green
structures in densifying hospital areas? What are
the key challenges?
The overarching method is Landscape
Biography. This is a method that is based on the
notion that landscapes are layered with stories,
and shaped by various ongoing processes. It is
a method that is interdisciplinary, it includes
history, geography and architecture and it
is promoted to include methods from other
fields as well. The research is non-linear,
it includes literature reviews, site analysis,
cartographic investigations, historical
research, visits to reference landscapes and
design. The literature review gives context
ABSTRACT
to driving forces of densification and theory
on alternative strategies in urban planning,
including evidence-based design for healthcare
environments. Site analysis provides practical
knowledge and insights to design challenges
within the area. Examination of maps exposes
the continuous transformation of SUS
Malmö and shed light on green structures
that have survived the process. Learnings of
former use and values within the landscape
are found in historical narratives. Visits to
reference landscapes provide inspiration for
design and shed light on factors important
for the survival of green space. Main findings
from the study are explored through design of
a specific area within SUS Malmö. The design
process is used as a method to investigate the
retrieved theoretical and practical knowledge.
The result is a design proposal where new
insights of the challenges within the landscape
become apparent. Many factors affect the
resilience of green structures, political, social,
historical and aesthetical are some of them. To
design for resilience, the various flows within
the landscape need to be acknowledged and
carefully considered in the process
Identifiering och uttryck av gener som är involverade I Ababinoxylans biosyntetiska bana
Get PDFOat is one of the most cultivated cereal crops in the world, and Arabinoxylan (AX) is a dietary fiber in oats with positive health effects. The biosynthetic pathway AX in Oat is still unknown, and which genes are active in its production. Ortholog genes have been identified in oat from other species like rice, wheat, barley, and Arabidopsis. These genes include GT43, GT47, GT61, UAM1, and UAM2. Expression analysis of three oat mutant populations was made in the early, middle, and late developmental stages. Quantifying of AX was also made in the reference oat variety Belinda in 4 different developmental stages. All genes analyzed were expressed in oat with a higher upregulation in the earlier stages except GT61. Accumulation of AX had a similar pattern, suggesting that AX accumulation and gene expression is higher in its first developmental stages. A phylogenetic tree was built using the protein sequences of GT43, GT47, GT61, UAM1, and UAM2 in Arabidopsis thaliana (At), Avena sativa (As), Oryza sativa (Os), Triticum aestivum (Ta), and Hordeum vulgare (Hv) by the maximum likelihood method. The phylogenetic tree showed homology between the genes in the different species. Another phylogenetic tree was also built for the genes identified in oat and showed a clear relation between the genes
Questioning public green space & affordable housing in times of densifying cities
Get PDFThis thesis examines the perceived relationship between public green space inequality in districts and how that is perceived to affect housing prices as greeneries value in cities has increased. The purpose is to investigate these perceived values and provoke questions in the thesis on how planning is experienced by active planners in the profession and how green spaces are viewed by residents. These connections are investigated with the help of a case study in two urban districts in Uppsala municipality. Eriksberg and Norby are the districts that are investigated, these are in the western part of Uppsala and differ from each other by, socio-economic background of the residents and housing types, form and among other things. The districts are chosen to be able to look at the perceived issues in different forms of urban districts. And in Eriksberg it is discussed what the consequences potentially be as it faces densification with new housing and renovation of existing homes. Affordable housing and methods to reduce segregation and prevent gentrification are discussed concerning the development and the districts as they are today from different perceptions. Meanwhile discussing the work against segregation, it is also discussed how the planners from Uppsala municipality are viewing and working with social sustainability in the correlation to green spaces decreasing. To be able to investigate these connections, empirical study, interviews with planners from Uppsala municipality and questionnaires in which residents in both Eriksberg and Norby have participated are used. Results from the methods combined with theories from researchers on the same subject are discussed at the end of the study. Conclusions drawn from a planner's perspective are that they need to work more actively with affordable housing. However, the planners never present a concrete plan or actions they are willing to take to deal with the problems that exist. The residents in the area feel strongly about nature and value it, however, the future development in Eriksberg is making the residents unsure of what will be left of nature. The residents are also unsure if they will afford to still live in Eriksberg after the development as the rents will increase. The planners say that everybody will not afford but most will. The quality of green spaces is questioned by the residents on how the municipality will act on the issue due to the lack of plans on how planners will implement socially sustainable solutions. Eriksberg is perceived to be engaged in questions that involve humans and biodiversity, meanwhile, residents in Norby are only engaged in questions that involve a change in their district, this is a strong sign that Norby is and wants to be segregated from other districts. Planners together with the municipality's active choice and stance on making housing accessible to all will reflect how segregated districts will become or remain in the future
Resiliens i det svenska lantbruket
Get PDFLivsmedel har alltid varit en viktig del i mänsklighetens förmåga att utvecklas. Men vad händer när
en störning påverkar landet och dess livsmedelsförsörjning? Sverige har länge haft en hög
självförsörjningsgrad på livsmedel. Men sedan Sverige gick med i EU 1995 har den minskat till
endast 50 %. Under den senaste tiden har även lantbruket påverkats av stora prishöjningar på
insatsvaror vilket kan leda till en lägre inhemsk produktion av livsmedel.
Frågan kring livsmedelsförsörjningen har blivit mer aktuell, det som påverkat i högsta grad är Covid-
19 pandemin och krig i Ukraina. Detta i sin tur ställer frågor kring lantbrukets motståndskraft där
resiliens är ett begrepp som beskriver ”ett systems förmåga att motstå svängningar i marknaden”
eller studsa tillbaka som ordets betydelse är på latin. Hur ser svenska lantbrukare och myndigheter
på livsmedelsproduktionen i Sverige och dess resiliens?
I denna studie redovisas ett arbete om hur svenska lantbrukare och myndigheter ser på lantbrukets
resiliens och dess påverkan på livsmedelsförsörjningen. Studien utförs med hjälp av kvalitativa
intervjuer som tar avstamp i det teoretiska ramverket, där begreppet resiliens beskrivs och hur det
kan implementeras i olika sammanhang. Inledningsvis ges en beskrivning kring lantbrukets
utveckling inom livsmedelsförsörjningen samt påverkan av det som händer i omvärlden.
Totalt medverkade fem respondenter, två lantbrukare samt tre sakkunniga på myndigheter som
jobbar med bland annat frågor kring livsmedelsförsörjning och resiliens. Respondenterna var
utspridda i Sverige vilket gjorde att vissa intervjuer kunde göras på plats medan vissa utfördes med
hjälp av videosamtal.
Sammanfattningsvis visar studien att det finns en bred syn bland respondenterna kring begreppet
resiliens. I modellerna syns två synsätt på resiliens där den ena är att återgå till det ursprungliga läget
och den andra är att utvecklas efter en störning. Myndigheterna som jobbar i ett större perspektiv
menar att förmågan att återgå till det normala är utgångspunkten, medan lantbrukarna som har sin
gård som utgångspunkt ser resiliens som förmågan att anpassa och utvecklas. För att förtydliga den
breda synen på resiliens utvecklade vi en egen modell på som inte har en cirkulär rörelse utan en
framåtgående rörelse. Efter det kom vi fram till ett förslag på ett ord som kan användas när återgång
till det normala inte är ett alternativ, proceliens. Begreppet kan beskriva hur en störning kan
användas för att utvecklas i stället för att åter gå till det normala.Food has always been an important part of humanity's ability to evolve. But what happens when a
disturbance affects the country and its food supply? Sweden has had a high degree of self-sufficiency
in food for a long time. Since Sweden joined the EU in 1995, it has decreased to only 50%. In recent
times, the agriculture has been affected by large price increases for inputs, which may lead to lower
domestic food production.
The issue of food security has become increasingly topical, some big impacts are the Covid-19
pandemic and the war in Ukraine. This leads to questions about the resistance of the agriculture.
Resilience is a term which describes "a system's ability to withstand fluctuations in the market" or
as it translates from Latin, bounce back. What are the Swedish farmers and authorities view of food
production in Sweden and its resilience?
This study reports the Swedish farmers and authorities view of agricultural resilience and its impact
on food security. The study is based on a theoretical framework, which describing the concept of
resilience and how it can be implemented in different contexts. By way of introduction, a description
is given of the development of agriculture in the food supply and the impact of what is happening
in the outside world.
A total of five respondents participated, two farmers and three experts at authorities who work with
questions about food supply and resilience. The respondents were spread over Sweden, which meant
that some interviews were done face-to-face while some were conducted with the help of videochat.
In summary, the study shows that there is a broad view among the respondents around the concept
of resilience. The models show two views of resilience where one view is to return to the original
state and the other one is to develop from a disturbance. The authorities work in a larger perspective
and believe that the ability to return to normal is the starting point, while farmers have their starting
point at their farm, see resilience as the ability to adapt and develop. In order to clarify the resilience
as a broad spectrum, we created a model who have a circular movement. After that, we came up
with a suggestion for a word that can be used when returning to normal is not an option, prosilience.
The new word can describe how a disturbance can be used to develop instead of returning back to
normal
Odling av växter för naturvård i Sverige
Get PDFFörlusten av biologisk mångfald är numera ett erkänt problem över hela världen. Många forskare och organisationer har gått ut med att vi måste restaurera stora naturområden med utarmade ekosystem för att bromsa och helst vända denna trend (Balvanera et al. 2019; IUCN 2019). För att göra detta räcker det inte alltid att använda sig av det växtmaterial som finns naturligt på platsen utan det kan även krävas komplettering med inköpta växter. I dessa fall är det ofta värden så som biologisk mångfald, genetisk variation och ekosystemtjänster som styr. Trädgårdsmarknaden är i dagsläget däremot mer inriktad på värden så som estetik, skörd och resistens.
I en del andra länder finns flera plantskolor som arbetar med inhemskt och oförädlat material som mer styrs av de värden som används inom naturvården (Basey et al. 2015). I detta arbete undersöker jag hur behovet ser ut för liknande plantskolor i Sverige och hur odlingsprocessen skiljer sig från konventionell odling.
Arbetet är baserat på enkätsvar och intervjuer. Det är uppdelat i en behovsanalys som fokuserat på naturvård i offentlig verksamhet och en processbeskrivning som fokuserat på odlingen och kompetensen hos olika odlingsföretag eller organisationer i Sverige. Hela arbetet inleds också med en kort litteraturstudie som undersöker hur växterna som används inom naturvård särskiljer sig och exempel på hur de kan användas.
Resultaten av arbetet visar att det finns ett stort behov av inhemska växter av lokal proveniens, något som inte erbjuds på marknaden i dagsläget. Odlingsprocessen skiljer sig en del inom detta område, främst då man inte arbetar med förädlade sorter. Det behövs kunskaper om de vilda växternas egenskaper och ståndorter samt kunskaper om hur man undviker selektion för att bevara en bred genetisk mångfald i odlingen.The loss of biodiversity is now a recognized problem worldwide. Many researchers and organizations have stated that we must restore large areas with degraded ecosystems in order to slow down and hopefully reverse this trend (Balvanera et al. 2019; IUCN 2019). To do this, it is not always enough to use the plant material that is naturally present on the site. It might be necessary to supplement with purchased plants. In these cases, it is often values such as biodiversity, genetic variation and ecosystem services that are important. The garden market, on the other hand, is currently more focused on values such as aesthetics, harvest and disease resistance.
Some other countries have plenty of nurseries that work with indigenous and natural plants and that are more led by the values used in nature conservation (Basey et al. 2015). This study aims to investigate the need for similar nurseries in Sweden and how the propagation process is different compared to conventional plant nurseries.
The methods are based on a questionnaire and interviews. It is divided into a customer demand analysis that focuses on nature conservation work in public sector and a process description that focuses on cultivation and competence within various relevant nurseries in Sweden. The thesis also begins with a short literature review that examines the characteristics of plants used in nature conservation and examples of how they can be used.
The results show that there is a great need for indigenous plants of local provenance, something that is not offered on the Swedish market at present. The propagation process is quite different compared to conventional plant production, mainly because the nurseries do not use cultivated varieties. The growers need to have knowledge of the characteristics and natural conditions for the relevant plant species as well as knowledge of how to avoid selection in order to preserve genetic diversity in production
Potato vine killing : effect on visual quality of the tuber depending on killing methods
Get PDFI matpotatisodling är knölens slutliga kvalitet alltid högt prioriterad, både den invändiga och utvändiga kvaliteten har stort fokus. Eftersom det har stort inflytande på konsumentens vilja att köpa produkten.
Efter att den kemiska substansen Dikvat blivit förbjuden inom EU, har sprutmedlet Reglone upphört att vara ett av de kemiska verktygen för blastdödning i svensk konventionell potatisodling och fått ersättas med andra alternativ. Förbudet har gett upphov till en upplevd försämring inom skalkvalitet och att andelen skalmissfärgning har ökat.
Syftet med arbetet är att undersöka hur blastdödningsmetoden påverkar den yttre kvaliteten hos potatis. Blastdödning är ett viktigt hjälpmedel för att plantan ska dö, vilket gör att knölen slutar växa och skalet kan mogna.
Det finns olika sätt att blastdöda potatis, både mekaniskt, termiskt och kemiskt. Inom de mekaniska metoderna ingår exempelvis blastkrossning, vältning och ryckning. Flamning och el - teknik är termiska alternativ, både mekaniskt och termiskt går även att använda i ekologisk odling. Det minst arbetskrävande är den kemiska metoden, där 60 g/l Karfentrazonetyl (Spotlight Plus) och 26,5 g/l Pyraflufenetyl (Gozai) är de två godkända medlen som fanns att tillgå hösten 2021.
För att kontrollera om blastdödningen gör någon skillnad på knölens yttre kvalitet sattes ett försök upp, där två olika behandlingar jämfördes. En behandling enbart innehållande kemiska insatser, där 0,8 l/ha Gozai (21,2 g Pyraflufenetyl) applicerades två gånger med 7 dagars mellanrum, vilket ger en totaldos på 42,4 g/ha. Den andra behandlingen bestod av blastkrossning kombinerat med vältning, vilket följdes upp 7 dagar senare med 1 l/ha Spotlight Plus (60 g Karfentrazonetyl). Behandlingarna upprepades på tre platser i en befintlig odling, därför är försöket inte helt randomiserat och innehåller stora försöksrutor.
När upptagningen av knölarna gjordes i hela provrutan, togs samtidigt mindre stickprov ut för visuell granskning, av en potatisrådgivare efter lagringstid. Alla prover sattes in i lager samtidigt, stickproven granskades och sorterades efter sjukdom/fel vid årsskiftet. Detta gjordes även med hela skörden av en optisk sorterare vid paketering.
I resultatet från stickproverna blev medeltalet för antalet bortsorterade knölar 42 % i båda behandlingarna. Det finns en statistisk signifikant skillnad i bortsortering mellan behandlingarna på en stickprovspunkt, där andelen bortsorterade knölar är högre i Gozai ledet. Annars finns enbart tendenser till skillnad mellan behandlingarna inom olika typer av skador/sjukdomar. Exempelvis tenderar andelen lackskorv att vara högre i blastkrossat led och mekanisk skada tenderar att vara högre i Gozai ledet. Stickproven skiljer sig dock beroende på vart i provrutan de är tagna, vilket gör att det finns statistisk skillnad inom försökrutan, framför allt i mätningen av specfikvikt och skalmissfärgning. När hela skörden från behandlingarna gått igenom den optiska sorteraren finns ingen skillnad mellan behandlingarna.
Försöket har få upprepningar och varje block har en stor yta, vilket skapar en variation inom provrutan och det ger ett opålitligt resultat. Försöket borde göras igen med fler upprepningar, på en provtagen jord för att få ett bättre underlag till lika förutsättningar. Det skulle ge ett resultat som är mer tillförlitligt.
I denna studie finns ingen statistisk skillnad mellan de två olika behandlingarna, utifrån frånsortering av kvalitetsskäl.
I resultatet finn vissa tendenser och en statistisk signifikant skillnad på att behandlingarna påverkar några av de skador och sjukdomar som återfinns på knölarna. Men med den låga andelen prov och den stora fältvariationen går det inte dra någon slutsats av detta, utan fler studier i ämnet behövs.In cultivation of table potatoes, the quality of the tuber is always high priority, both the internal and external quality is in great focus. The appearance is important, because it has a major influence on the consumer´s willingness to buy the product. After EU banned the chemical substance Diquat, the pesticide Reglone got removed from the market and the strategy for vine killing in potato production needed to change. After the ban, the feeling of tubers having worse skin quality and more skin discoloration has occurred.
The purpose of this work is to investigate how the vine killing method effects the external quality of the tubers. Potato crop is the fifth most cultivated crop in the world and that makes the knowledge of how good quality is achieved important. Vine killing is one of the important things that makes the farmer able to control tuber quality. It plays an important role for the skin set to start, which is important for protection of the tuber, both from diseases and skin injuries.
To vine kill you can use different methods, mechanical, thermal, and chemical. The mechanical strategy includes flail chopping, rolling, and vine pulling. Possible thermal methods consist of flaming and electrocution. Both mechanical and thermal methods are often used in organic farming. Last, we have the chemical method, which is least labour-intensive and the most common in conventional cropping. In autumn 2021 there were two approved substances for vine killing, 60 g/l Carfentrazone ethyl (Spotlight Plus) and 26,5 g/l Pyraflufen-Ethyl (Gozai).
To check if the vine killing method affect the external quality of the tuber, an experiment was setup to compare two different methods. The first strategy contained only chemical treatment, in form of 0,8 l/ha Gozai (21,2 g Pyraflufen-Ethyl), which was applied twice at a 7-day interval. The second strategy consisted of flail chopping combined with rolling, which was followed up 7-days later with 1 l/ha Spotlight Plus (60g Carfentrazone ethyl). The treatments were repeated 3 times in an existing culture, therefore the plots were not completely randomized and the area contained uncounted variations.
When the big samples were harvested, smaller samples were taken at specific places in the field, for visual inspection by a potato expert after a time in storage. All samples were placed in the same storage, at the same time. The smaller samples were examined and sorted by disease/error in late December 2021 and in January 2022. The main samples were put through the production line and sorted by an optical sorter during packaging, this action was performed continuously during February 2022.
The small samples from both treatments had an averaged result of 42% tuber removed for bad external quality. There was a statistically significant difference of removed tubers at one of the places, where the smaller samples were taken. The higher amount of tuber removal occurred in the Gozai treatment. There were tendencies to difference in what type of injuries/diseases the tuber got removed for. Every plot area was big in size, but the smaller sample plots were placed in a way that were supposed to eliminate the infield difference, if they were compared to the plots beside them. But if the small samples were compared along the rows, there were a tendency to difference between the start of the field and the end. The difference was observed in the measurement of the specific gravity and in removal due to skin discoloration. The bigger samples do not show any differences between the treatments. The big conclusion is that the treatments are not repeated enough to get a respectable number of samples, the blocks are also in a vast area where the soil can shift a lot. To obtain a better result, a new test should be done with new soil samples and smaller blocks.
This study shows that the two tested vine killing method, fail chopping + 1l/ha Carfentrazone ethyl and 0,8l/ha Pyraflufen-Ethyl + 0,8l/ha Pyraflufen-Ethyl, doesn’t make a difference on the external quality of the tuber.
The results show trends and one statistically significant difference in the treatments that influence what kind of disease or injuries the tuber get. The amount of black scurf tends to increase in flail chopping + Spotligth Plus. The mechanical damage on tubers tends to be higher in Gozai + Gozai, but the samples are few and that makes a conclusion impossible
How hot are retention patches as structural hotspots? : comparing key elements for biodiversity in retention patches and reference forest stands
Get PDFSweden’s historical and current forestry regime has created structurally simplified
forest stands with little resemblance of boreal old-growth forests, leading to a
decline in many forest dwelling species. Retention forestry was introduced to
counteract the negative development by retaining biologically important forest
elements. Retention patches are intact forest areas left to represent conditions in the
pre-harvest stand for harbouring of threatened species and structurally enriching
managed forests. However, many biodiversity preservation goals connected to
forests remain unfulfilled, which indicate a need for evaluation of what is retained
during harvest and possible influences on why. I used the Swedish Forest Agency
method for inventorying woodland key habitats to evaluate differences in substrate
supply, conservational quality and physical prerequisites in retention patches
compared to structurally similar reference forest stands located in spruce�dominated boreal forests in Hälsingland, Sweden. My results showed how retention
patches scored lower in the natural value assessment, contained less deciduous live
conservation trees and less coarse deadwood. In general, substrate amounts are
either lower or indifferent in retention patches compared to in reference forests,
indicating that retention patches are not structural hotspots. If retention patches do
not hold equal conservation values as the pre-harvest stand, the forest landscape
would continuously be impoverished, and the threatened species disfavoured. The
structure of retention patches, underlying causes of retention decisions, and
following implications for biodiversity need further studying to ensure that areas
with the highest conservational importance are preserved