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Growth of Zea mays in response to artificial inoculation with endophytic Beauveria bassiana compared to Trichoderma sp. “atroviride B”
No full textDemand for sustainable crop production is putting pressure on growers to improve yield while using environmentally friendly solutions. Recently, entomopathogenic fungi have been reported to promote plant growth under certain conditions; however, colonisation of plants as endophytes may be inconsistent or persistence within plant tissues brief. We studied the effects of inoculating three Beauveria bassiana isolates in comparison with a known plant-growth-promoting isolate of Trichoderma sp. “atroviride B” as a positive control, on the growth of maize (Zea mays L.). We tested the plant response by measuring multiple parameters including biomass, length, chlorophyll content and root architecture following inoculation, to identify even subtle plant growth effects. Fungal isolates were inoculated by inserting hyphae through a small wound made in the stem of emerging seedlings, a technique that has not been previously used for B. bassiana. Results showed neutral effects on biomass, but plants exhibited root architecture changes because of inoculation with B. bassiana isolate (FRh2), which increased fine root length and because of T. sp. “atroviride B” which increased larger diameter root length. A higher chlorophyll content was observed for plants inoculated with B. bassiana isolate (J18), although this did not correlate with biomass differences. The inoculation technique enabled the comparison of systemic effects to the plants and may have affected subtle but important root-trait modifications. Changes to root architecture can impact resource acquisition in plants, therefore this study highlights the importance of measuring various physiological changes in the plant host when assessing for potential growth effects
Street smart: Do effective design guidelines exist for enhancing the main streets of rural small towns in New Zealand through landscape architecture? : A dissertation submitted in partial fulfilment of the requirements for the Degree of Masters of Landscape Architecture at Lincoln University
Get PDFRural small towns are significant contributers economically, culturally, recreationally and socially In New Zealand. They often function as service centres for surrounding agriculture operations, as well as key settlements for tourism, both of which are the counties top two export industries. However in recent years the attraction and liveability of these rural towns has caused many residents to leave and few tourist to visit. A major contributor to the recent decline in these significant towns is the safety, usability and attractiveness of the towns main streets. In New Zealand there are broad landscape and urban design guidelines for metropolitan centres such as Auckland and Christchurch, however there is no governing design document for rural small towns in decline. This dissertation will answer the primary research question of: Do effective design guidelines exist for enhancing the main streets of rural small towns in New Zealand through landscape architecture?. However It was established that there are no design guidelines existing for main street design of rural small towns in New Zealand. Therefore within this dissertation an effort to identify and describe key principles from existing guiding documents and adapt and abstract them to suit rural small towns in the hope of reversing the recent decline has been undertaken
Editorial: Insect physiological changes during insect-plant interaction
Get PDFThe interactions between phytophagous insects and their host plants result from a long and continuous evolutionary process (Beran and Petschenka, 2022). Such ecological relationships led to an extraordinary diversity of insects and shaped their complex physiological systems (Wheat et al., 2007). The impacts of host plants on the physiology of herbivorous insects have increasingly become a paramount focus that should not be ignored. Chemical compounds’ composition of plants have not only significant variations in the inter/intra species aspect but also show spatiotemporal variations in different developmental stages and tissue types, or under changeable environments in nature, which lead to the resource assimilation and fitness challenges of insects (Delucia et al., 2012; Brütting et al., 2017). These close interations with plants affect the ecological plasticity of the performance of insect herbivores (Barker et al., 2019). Currently, in-depth exploration of the host plants’ effect on insects has become a research hotspot of insect physiology, however to test the highly complex hypothesis can be difficult. The current Research Topic aimed to highlight the recent developments on 1) how physiological changes occurred in herbivores during their interaction with host plants, 2) how these physiological changes in insects could be affected by other biotic factors
Exploring the terminology, definitions, and forms of Post-Occupancy Evaluation (POE) in landscape architecture
Get PDFWhile the concept of Post-Occupancy Evaluation (POE) is widely applied in landscape architecture and other relevant fields, the term POE is not well-defined. By reviewing and analysing a representative set of POE definitions collected from existing academic and grey literature using content analysis methods, this study aims to enhance understanding of the breadth of the concept and its relevant practices. Our research found that the concept of POE was developed in architecture in the 1970s and subsequently adopted in landscape architecture in the 1980s. With the growth of the field in architecture and its adaptation to landscape architecture, the scope of POE was significantly expanded over recent decades, and with this growth, there have been considerable divergences in definitions and understandings of how to carry out POE. A range of different evaluation objects and four evaluation models were identified by this study. By surveying the conceptual terrain of POE, our research establishes the need for practitioners to be aware of the breadth of the concept and the potential ambiguity surrounding what is meant by the approach. Consequently, practitioners need to be specific and explicit about their understanding of POE. The findings also demonstrate how interdisciplinary differences appear to have been overlooked when adapting POE from one discipline to another. We, therefore, argue that it is crucial to keep shaping and trimming the concept to support the adaption of POE processes into different disciplinary domains
Pedogenic pathways and deep weathering controls on soil organic carbon in Pacific Northwest forest soils
Get PDFCharacterizing the distribution and dynamics of organic carbon in soil is critical for quantifying changes in the global carbon cycle. In particular, weathering controls on near-surface and deep (>1 m) soil organic carbon (SOC) dynamics have been proposed but limited data prevents us from predicting SOC over topographically complex landscapes and quantifying how changes in climate and perturbations, such as wildfire or land management, influence SOC stocks. To advance our understanding of how weathering alters soil geochemistry and influences SOC storage, we synthesize previous data with a new analysis of the Siuslaw River soil chronosequence from terraces in the Oregon Coast Range, a region that harbors the richest SOC inventories in the continental US. We analyze how the relationships between soil geochemistry, physical properties, and SOC storage vary with weathering status and pathways across soils that span 0.041 to 990 kyr and vary in depth from 1 m to >10 m. To distinguish the key properties and processes influencing SOC storage at different depths, we break our analysis into three depth intervals: 0–30, 30–100, and >100 cm. Our results suggest that the processes that control SOC stocks vary systematically with time and depth owing to weathering impacts on soil properties and pedogenic development. At 30 kyr we observe a peak in SOC stock in the top 100 cm coincident with a peak in oxalate extractable Al and Fe concentrations, representing secondary poorly crystalline minerals, which is consistent with previous studies. We also observe a decline in shallow SOC stock for >30 kyr soils as poorly crystalline minerals are replaced by more stable crystalline forms and soils become clay dominated. At 120 kyr, SOC below 100 cm starts to contribute significantly to the total SOC profile inventory and by 990 kyr, this fraction composes >40% of the total SOC stock. Taken together, our results indicate that total SOC stock increases with soil age as the increased intensity of bedrock weathering deepens the critical zone, creating accommodation space for deep SOC storage. These findings reveal the intimate link between poorly crystalline minerals and SOC and suggest that systematic analysis of soil development in the critical zone provides a first-order constraint on SOC stocks
An introduction to rural and agricultural development in the digital age
Get PDFThis special issue contributes to the development economics literature by highlighting the role of information communication and technologies (ICTs) in supporting rural and agricultural development. It is comprised of nine papers. Key findings from this special issue include: (1) internet use increases rural consumption diversity and agricultural productivity; (2) smartphone use empowers rural women in household decision-making and off-farm work participation; (3) smartphone-based agricultural extension services boost rural income growth; (4) a lack of ICT infrastructure and inadequate skills to use digital technologies are two key factors that lead to digital poverty traps for smallholder rural farmers; (5) ICT adoption increases the probability of rural households' access to credit and empowers rural women and farm households in relatively less developed regions to access credit; (6) digital financial inclusion reduces farmers' vulnerability to poverty; and (7) e-commerce adoption increases both sales prices and marketing costs, but the magnitude of increasing the former is higher than the magnitude of increasing the latter, which finally contributes to a higher gross return. This special issue also proposes practical instruments and implications for advancing the application of ICTs in rural areas to accelerate rural and agricultural development in the digital age
Can mechanized pesticide application help reduce pesticide use and increase crop yield? Evidence from rice farmers in Jiangsu province, China
Get PDFThis study is devoted to analyzing the effects of outsourcing machinery-intensive farming activities vis-à-vis using mechanized equipment in-house on pesticide use, utilizing cross-sectional data collected from rice farmers in Jiangsu province, China. The control function approach is utilized to address the endogeneity of the decision to outsource pesticide application or complete the task in-house. Our results suggest that outsourcing pesticide application decreases pesticide expenditure but in-house application using mechanized equipment increases it. Specifically, outsourcing pesticide application reduces pesticide expenditure by about 81 yuan per mu or around 0.18 yuan per kilogram of rice produced. In comparison, the in-house application using mechanized equipment increases pesticide expenditure by 118 yuan per mu or by 0.14 yuan per kilogram of rice output. We also find that both outsourcing and in-house pesticide applications increase rice yield
Root aphid (Aploneura lentisci) population size on perennial ryegrass is determined by drought and endophyte strain
Get PDFClimate change is anticipated to lead to an increase in the occurrence and intensity of drought and fluctuations in insect cycles that will challenge modern pasture systems. Feeding by root aphids such as Aploneura lentisci Pass. can be a significant challenge to pastures. These below-ground living aphids are commonly found in New Zealand and Australia, feeding year-round on the roots of graminaceous plants such as perennial ryegrass (Lolium perenne L.). Some strains of the fungal endophyte Epichloë festucae var. lolii in perennial ryegrass can provide protection against root aphids and greater resilience under drought, contributing to higher persistency and growth than endophyte-free plants. However, the interaction between insect pressure and drought is not understood. This study examined the effect of drought on root aphid populations and plant performance in perennial ryegrass plants relative to endophyte status (±) and endophyte strain (AR37, NZCT) in a glasshouse experiment. Plants were cloned across the drought and well-watered treatments, and half of the plants were inoculated with root aphids, whilst half of the plants were treated with insecticide. Endophyte infection with strain NZCT and AR37 reduced root aphid numbers. Aphid populations were significantly higher in drought-stressed than in well-watered plants in both endophyte-infected and endophyte-free treatments. Under drought conditions, root aphid populations were increased 4-fold in NZCT and 8-fold in AR37 and endophyte-free plants in comparison with their well-watered counterparts. Root aphids reduced shoot dry weight by 16% in drought-exposed and 26% in well-watered plants in comparison with their insecticide-treated counterparts whilst reducing root biomass by 49%. Our results suggest that root aphids are likely able to exploit the higher availability of amino acids in the plant sap of drought-exposed plants. This study provides evidence that climate change-mediated impacts of root aphids could reduce production in perennial ryegrass-dominant pastures. However, field trials would be necessary to determine whether this effect is seen in situ, where numerous additional factors will be operating at the same time
The taxonomy, systematics and ecology of jumping spiders (Araneae: Salticidae) inhabiting the South Island rocky alpine zone : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science at Lincoln University
Get PDFThe salticid (jumping) spider family is among the most heavily researched groups of invertebrates globally. Nevertheless, in Aotearoa New Zealand the vast majority of species have never been studied. While it is estimated there are approximately 200 endemic salticids found across the country, only around 50 have been described, and fewer than 10 are reliably identifiable. Of those inhabiting the alpine zone, none can be identified to genus or species, although it is widely recognised that these taxa exist. To address this, a search was conducted for Salticidae at 21 rocky alpine sites throughout the South Island to obtain a representative selection of specimens across their range. Through morphological examination and phylogenetic analysis of COI sequence data, 12 new alpine species were identified. Together these taxa comprise a new genus within the salticid family. Further phylogenetic analysis of combined COI and actin 5C datasets placed the new genus within the Australasian Astioida clade, and likely within the Viciriini tribe.
Using the 170 specimens collected during this fieldwork, plus some from existing collections, formal descriptions are provided for the new genus, here named Ourea gen. nov., and 12 new species. These spiders include some of the largest salticids known from New Zealand, and are remarkably well camouflaged on the rock substrates they inhabit. The genus is common and widespread throughout the South Island, with at least one species found at every rocky alpine locality visited in the study. In addition to the alpine species described here, the genus includes several lower-altitude taxa which remain to be described, and probably many more from throughout the country. It is also likely that three Subantarctic species, currently misplaced in the genus Clynotis (Simon 1901), and a widespread mainland species, Trite pollardi (Patoleta & Zabka 2017), would be better placed in this genus.
Field observations regarding the natural history of Ourea gen. nov. incuding distribution, life cycle, reproduction, diet and threats were recorded. Although most of the species described here were found exclusively in the alpine zone, one occurred in rocky habitats from sea level to above 1500 m. Parasitism by pompilid wasps was observed in two taxa. Intraspecific behaviour in the wild was unusual in that six of the species were found living closely together in conspecific, and even congeneric, groups. Despite this, cannibalism was also observed. Intraspecific display behaviour, studied in a laboratory setting, is described for a subset of four species. Displays were of similar complexity compared to other Salticidae
Relationship between internet use and negative affect
Get PDFWhile positive emotions like happiness and life satisfaction have received great attention, how to eliminate negative affect is largely neglected. This study contributes to the literature by examining the relationship between Internet use and people’s negative affect. Unlike previous studies that consider only one indicator, we capture negative affect from different dimensions by considering loneliness, sadness, and life hardship. We employ an endogenous ordered probit model to address the selection bias of Internet use and analyze the 20,107 individual-level samples sourced from the 2020 China Family Panel Studies survey. The results show that Internet use significantly reduces people’s loneliness, sadness, and life hardship. We also find that studying online and watching short videos would increase people’s loneliness feeling and shopping online deepens people’s life hardship. In contrast, using WeChat significantly reduces sadness and life hardship. Our findings confirm that guiding people to use the Internet appropriately is necessary to reduce negative affect and improve the quality of their life