Department of Agricultural Sciences
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The Department of Agricultural Sciences consists of animal science, plant science and farm management and agribusiness staff members.
The range of research conducted is quite extensive including: conversion of forests into pasture, alternative dryland pasture species, grain legume agronomy, sustainability in farming systems, nitrogen fixation and nitrogen cycling, shelter on dairy farms, economic viability of NZ farming systems, animal nutrition, immunology etc.
Recent Submissions
Item Screening and identification of lncRNAs in preadipocyte differentiation in sheep(Springer Nature, 2024-03-04) Hao, Z; Jin, X; Hickford, Jonathan; Zhou, Huitong; Wang, L; Wang, J; Luo, Y; Hu, J; Liu, X; Li, S; Li, M; Shi, B; Ren, CStudies of preadipocyte differentiation and fat deposition in sheep have mainly focused on functional genes, and with no emphasis placed on the role that long non-coding RNAs (lncRNAs) may have on the activity of those genes. Here, the expression profile of lncRNAs in ovine preadipocyte differentiation was investigated and the differentially expressed lncRNAs were screened on day 0 (D0), day 2(D2) and day 8(D8) of ovine preadipocyte differentiation, with their target genes being predicted. The competing endogenous RNA (ceRNA) regulatory network was constructed by GO and KEGG enrichment analysis for functional annotation, and some differentially expressed lncRNAs were randomly selected to verify the RNA-Seq results by RT-qPCR. In the study, a total of 2517 novel lncRNAs and 3943 known lncRNAs were identified from ovine preadipocytes at the three stages of differentiation, with the highest proportion being intergenic lncRNAs. A total of 3455 lncRNAs were expressed at all three stages of preadipocyte differentiation, while 214, 226 and 228 lncRNAs were uniquely expressed at day 0, day 2 and day 8, respectively. By comparing the expression of the lncRNAs between the three stages of differentiation stages, a total of 405, 272 and 359 differentially expressed lncRNAs were found in D0-vs-D2, D0-vs-D8, and D2-vs-D8, respectively. Functional analysis revealed that the differentially expressed lncRNAs were enriched in signaling pathways related to ovine preadipocyte differentiation, such as mitogen-activated protein kinase (MAPK) pathway, the phosphoinositide 3-kinase protein kinase B (PI3K-Akt) pathway, and the transforming growth factor beta (TGF-β) pathway. In summary, lncRNAs from preadipocytes at different stages of differentiation in sheep were identified and screened using RNA-Seq technology, and the regulatory mechanisms of lncRNAs in preadipocyte differentiation and lipid deposition were explored. This study provides a theoretical reference for revealing the roles of lncRNAs in ovine preadipocyte differentiation and also offers a theoretical basis for further understanding the regulatory mechanisms of ovine preadipocyte differentiation.Item Horticultural management - Financial planning(Lincoln College, University College of Agriculture, 1982) Stevens, R.B.Financial planning is an essential function of the business manager. While none of the financial planning techniques are mathematically difficult, the role of those techniques in integrating the numerous business functions and describing their inter-relationships often gives the appearance of complexity. The purpose of this manual is to present instructional material and worked examples on financial planning techniques in a clear and structured manner. This manual will be complemented by individual study guides for each of the six sections in the course. These will state the educational objectives for each section and questions and exercises that must be done to show understanding and mastery of those stated objectives. It is not intended that this manual replace the desirability of attending lectures and tutorials or to take additional notes as appropriate. In fact, the manual layout has been designed to permit and encourage supplementary note-taking. Further explanation of topics, together with detailed examples will be given in lectures to elaborate on the content of the manual. The references or readings cited should be read to provide a broadened appreciation of the study topics.Item Horticultural management - Critical Path Method(Lincoln College, University College of Agriculture, 1982) Stevens, R.B.The CPM family of planning techniques are a potent tool in the organisation and control of work programmes. Techniques such as these are no panacea: problems in t.he collection of data, the setting of subobjectives and in the implementation of the work plan are recurring decisions to be taken by management otherwise the benefits of the formalised expression of the work plan will be negated. The use of CPM in horticulture has, to date, been limited to a few construction, crop scheduling and planting programmes. However, as the maintenance and development operations of local authority parks departments in particular, become constrained by the availability of finance, greater emphasis will be placed on the optimum utilisation of resources and associated financial control. For determining project resource requirements, for constructing the resource use plan and for assessing the project cost with regard to quantifiable contingencies, the critical path methods have, at present, no equal.Item Lactobacillus buchneri and molasses can alter the physicochemical properties of cassava leaf silage(Elsevier B.V., 2023-11) Bakare, AG; Zindove, Titus; Bhavna, A; Devi, A; Takayawa, SL; Sharma, AC; Iji, PAIn developing countries where feed resources are scarce, cassava leaves can be used as feed for animals. However, the use of cassava leaves is limited mainly because of their high fibre content and overall acceptability by animals. The resolution to this problem is to process the cassava leaves by ensiling and using additives. Therefore, the objective of the study was to determine the effects of including different inclusion levels of molasses and bacteria concentration on the physicochemical properties of cassava leaf silage. Molasses was added at inclusion levels of 0, 3, 5 and 7 g/100g of the chopped cassava leaves, and Lactobacillus buchneri was mixed with chopped cassava leaves at different concentrations of 0, 3.1 × 10⁶ cfu/ml, 3.1 × 10⁸ cfu/ml and 3.1 × 10¹⁰ cfu/ml. The effects of inclusion level of molasses on the colour, smell and texture of cassava leaf silage were significant (P < 0.05). Inclusion of bacteria concentration also influenced the smell of silage (P < 0.05). Effects of the inclusion level of molasses and bacteria concentration resulted in decreased pH, crude protein and crude fibre of silage (P < 0.05). There was a quadratic relationship between Ca and K with inclusion level of molasses in cassava leaf silage (P < 0.05). A positive linear relationship was observed between Mg and molasses inclusion levels in cassava leaf silage (P < 0.05). Using principal component analysis (PCA), molasses had a strong positive correlation with PCA 1, whereas crude fibre, pH and crude protein had a positive correlation with PCA 2. The inclusion level of bacterial concentration was negatively correlated to Ca, CP, P and CF. From the study, the use of molasses and L. buchneri can greatly improve the physicochemical qualities of cassava leaf silage.Item ESMAX for spatial agroecology: A conceptual spatial model for the quantification and visualisation of ES performance from different configurations of landscape(Wiley & Global Initiative of Sustainable Agriculture and Environment, 2024-03) Morris, R; Davis, Shannon; Grelet, GA; Gregorini, PabloIntroduction: Agriculture is confronted by the dual challenges of increasing global demand for food production while reducing negative impacts on the environment. One suggested solution is transitioning modern industrial agriculture to more agroecologically-informed practices, thus realigning increased food production with the carrying capacity of Earth Systems. The transition to multifunctional agroecological systems, that promote the production of multiple ecosystem services (ES) as well as food production, requires an adaptive management process that addresses climate-change, market complexity, practical implementation and knowledge transfer. Materials & Methods: This work proposes a spatially explicit methodology to support this process. Spatial agroecology, in this context, combines a new Geographic Information Systems (GIS)-based model (ESMAX) with development of a ‘solution space’ to assist stakeholders identify configurations of agroecological components (in this case, trees on farm) at the scale of a 1 ha paddock to supply a targeted range of regulating ES (cooling effect, flood mitigation and habitat). ESMAX uses distance-decay characteristics specific to each type of regulating ES to quantify and visualise the influence of spatial configuration of ES-supplying tree clumps on overall ES performance. Results: The results from this application of spatial agroecology suggest regulating ES production at farm and paddock scale is influenced by the arrangement of trees on farm. ESMAX's results show paddocks with large tree clumps return the best cooling effect, while small clumps deliver the best flood mitigation and most suitable habitat. Evenly dispersed arrangements of small tree clumps provide the best multifunctional performance across all three ES modelled in this work. Conclusion: Designed spatial agroecological interventions can affect landscape multifunctionality at paddock scale, where practical decisions are made and implemented. This provides spatially explicit support of an adaptive management process. Utilising agroecological systems as spatial mechanisms for supplying critical regulating ES also highlights a new function for agriculture in the Anthropocene epoch.