Use of ERTS-1 data to assess and monitor change in the Southern California environment

There are no author-identified significant results in this report

A scoping study of IPM compatible options for the management of key vegetable sucking pests: Final report (Project Number: VG06094)

BACKGROUND BRIEFING The availability of specific soft option products for other pests such as Lepidoptera species control in vegetables has increased the importance of sucking pests in the modern day pest spectrum. Current vegetable sucking pest management practices are still heavily reliant on older broad spectrum pesticides. These non selective products prevent further adoption of an integrated pest management (IPM) system, and their frequent, multiple crop use pattern has the potential to enhance resistance development in the pest population. A limited number of more recently developed, pest specific or “softer” products for example spinosad (Success®) and pymetrozine (Chess®) are registered in some specific vegetable crops. The management of sucking pests is also complicated by the fact that virus transmission and product contamination are as, if not more important than the physical damage they can cause to vegetable crops. To modernise sucking pest control in the vegetable sector, work in a range of overlapping multifaceted areas needs to occur. A team of entomologist in consultation with crop consultants, growers and specialist reviewers conducted a scoping study of the impact of at least 5 sucking pests commonly found across vegetable crops. Literature reviews, an industry workshop, interstate producer interviews and farm visits were employed to collate information on current best 'fit' management options within an IPM system, relevant to the particular vegetable and potential future management options. Ideas for future research, development, and extension activities highlighted in the workshop process included ; biopesticides, improved beneficial insect management in current cropping systems, monitoring and early warning, improved knowledge of pest ecology, resistance issues, improved soft option products, increased grower awareness and information, extension and publications. Developing and testing fungal biopesticides against sucking pests, managing insecticide resistance and field testing biocontrol agents against thrips were considered the top three topics for further research of 28 topics listed and prioritised by the workshop participants

Agroforestry Opportunities for Enhancing Resilience to Climate Change in Rainfed Areas,

Not AvailableAgroforestry provides a unique opportunity to achieve the objectives of enhancing the productivity and improving the soil quality. Tree systems can also play an important role towards adapting to the climate variability and important carbon sinks which helps to decrease the pressure on natural forests. Realizing the importance of the agroforestry in meeting the twin objectives of mitigation and adaptation to climate change as well as making rainfed agriculture more climate resilient, the ICAR-CRIDA has taken up the challenge in pursuance of National Agroforestry Policy 2014, in preparing a book on Agroforestry Opportunities for Enhancing Resilience to Climate Change in Rainfed Areas at ICAR-CRIDA to sharpen the skills of all stakeholders at national, state and district level in rainfed areas to increase agricultural productivity in response to climate changeNot Availabl

Genotypic variation in climbing ability traits in a common bean RIL population

Climbing beans are vines that can be grown in either monoculture using wooden or bamboo trellises or in intercropping with other support crops such as maize, but in either case an important characteristic of climbing beans is their vegetative vigor and climbing ability. A range of climbing bean architecture exists; some are extremely vigorous producing more biomass at the top of the plant (type IVb), while others distribute biomass more uniformly across their the length of their vines (type IVa). Different types are selected by farmers in given situations, depending on climate, cropping system, harvesting method and growing period. Few studies have analyzed the inheritance of climbing ability in common bean or analyzed the interaction of this trait with soil fertility levels. Information about climbing ability and its component traits could be used by plant breeders to develop climbing bean ideotypes for different production systems. Therefore one of our research objectives has been to develop methods to analyze climbing bean growth and apply these to genetic mapping populations. In this research we analyzed a population of recombinant inbred lines derived from the cross of a climbing bean, G2333, by a bush bean, G19839, grown under high and low phosphorus treatments, for traits involved with climbing ability

The Potato Crop

Life sciences; Agriculture; Nutrition   ; Plant breeding; Food—Biotechnology; Agricultural economic

Fruit Metabolism and Metabolomics

Over the past ten years, metabolomics strategies have allowed the relative or absolute quantitation of metabolite levels for the study of various biological questions in plant sciences. For fruit studies, in particular, they have participated in the identification of the genes underpinning fruit development and ripening. This book proposes examples of the current use of metabolomics studies of fruit for basic research or practical applications. It includes articles about several tropical and temperate fruit species. The studies concern fruit biochemical phenotyping, fruit metabolism during development and after harvest, including primary and specialized metabolisms, or bioactive compounds involved in fruit growth and environmental responses. The analytical strategies used are based mostly on liquid or gas chromatography coupled with mass spectrometry, but also on nuclear magnetic resonance and near-infrared spectroscopy. The effect of genotype, stages of development, or fruit tissue type on metabolomic profiles and corresponding metabolism regulations are addressed for fruit metabolism studies. The interest in combining other omics with metabolomics is also exemplified

Population Genetics, Distributions and Phenology of Bombus Latreille, 1802 and Xylocopa Latreille, 1802 (Hymenoptera: Apidae)

This work addresses multiple knowledge gaps in bee ecology, population health and phylogeography in order to provide insights into the changing distributions of native bees. A comparison of Arkansas bumble bee records mirrors range-wide surveys, with records of stable species (Bombus bimaculatus Cresson, 1863 and B. impatiens Cresson, 1863) increasing three-fold, and records of the declining B. pensylvanicus (DeGeer, 1773) dropping to 60% of historical levels. However, nationally-recommended conservation-genetics tools did not mirror these results on a regional level. Stable and declining species had equivalent genetic diversity in samples from Arkansas and Tennessee (HS range: 0.46-0.63). Diploid males, which indicate inbreeding, were only detected in the species known to be stable, B. bimaculatus and B. impatiens. This could be an indication of broad similarity of these taxa in the region, or it could indicate that recommended microsatellite-based tools are less likely to detect genetic signatures of declines at a localized level. A three-year survey of floral associations and seasonality in a community of eight bee species across Northwest Arkansas found that local and landscape factors had no effect on the differential abundances of this community, but overall abundance increased with increasing plant richness at each site (F(1,11)=45.62, p\u3c0.001), as did the abundance of each bumble bee species. Bumble bees with long glossae, a group usually thought to be at higher risk of decline, were more specialized in their flower use, and although their food choices overlapped (O12=0.54), they skirted potential competition by maintaining different phenologies. Subspecies status was maintained for Xylocopa virginica texana Cresson, 1872, but not for X. v. krombeini Hurd, 1961. This morphological east-west differentiation is additionally supported by mitochondrial phylogeographic analyses which suggest that X. virginica expanded from multiple glacial refugia. On the other hand, X. micans haplotypes are consistent with a single origin, likely west of the Mississippi River. In spite of its interpopulation homogeneity, X. micans is quite genetically diverse (Hd=0.91±0.03) compared to X. virginica and (Hd=0.78±0.02), consistent with Hewitt\u27s leading-edge hypothesis for range disparity. Together, these results highlight the importance of an ecological perspective in the quest to understand bee distributions and decline

Nicotiana attenuata microbiome characterization and plant-bacterial interactions from single isolates to consortia

Plants rely on soil microbes for beneficial interactions i.e., growth promotion, nutrient availability and disease suppression. Biotic and abiotic factors shaping the root microbiome are still largely unknown. Furthermore, why and how plants acquire soil microbes during germination and their ecological and functional roles remain elusive. Most of the high-throughput sequencing studies are limited to model or crop plants and lack the complementation of a culture-dependent approach to reveal functional traits of dominant and rare microbial communities. Until now, poly-microbial disease complex and poly-microbial biocontrol application received little attention in the scientific community. In this dissertation, my work aims to address these intriguing questions. During my research work, I investigated the influence of the phytohormone jasmonic acid (JA) and plant developmental stages on leaf and root bacterial communities in wild tobacco N. attenuata. Roots and leaves of field grown plants of a previously characterized, isogenic line impaired in JA biosynthesis (irAOC) and an empty vector (EV) control line were harvested over five different developmental stages from rosette to flowering stages. A 454- pyrosequencing and culture dependent method were employed to characterize the bacterial communities. Neither JA nor plant developmental stages shaped the bacterial communities; however, tissue type had a major effect on community composition. Roots harbored higher bacterial diversity compared to leaves, irrespective of genotypes. The culture-independent results were further validated by a culture-dependent approach and demonstrated that JA does not influence the bacterial community composition of N. attenuata. Furthermore, bacterial plant growth promoting (PGP) effects are independent of the plant’s ability to produce endogenous JA. Moreover, I hypothesized abiotic factor such as soil types and the plant’s response to UVB exposure shape the N. attenuata root microbiome. To test this hypothesis, we harvested native grown N. attenuata from different locations at the Great Basin Desert, Utah. Deep-sequencing analysis revealed that root bacterial communities were independent of soil types. Moreover, root bacterial communities from five different locations clustered separately compared to soil types in a non-metric multi-dimensional scaling plot (NMDS), although chemical properties of soils are different. Diversity of soil samples is higher compared to roots and plants selectively recruit the microbial communities from soil, irrespective of location and genotypes. However, fungal recruitment is less specific by plants. Interestingly, in N. attenuata, the phylum Deinococcus-Thermus is unique compared to other plant species and more abundant in roots than in soils, which indicates selective enrichment of Deinococcus members in N. attenuata roots. Based on the UV resistant trait of Deinococcus-Thermus and the native habitat of N. attenuata characterized by high UVB fluence rates.We hypothesized that, plants response to UVB exposure and its UVB perception receptor UV RESISTANCE LOCUS 8 (UVR8) and response -flavonoid biosynthesis enzyme chalcone synthase (CHAL) – influences the colonization of Deinococcus- Thermus. We generated an isogenic line impaired in UVR8 expression (irUVR8) and used it along with a previously characterized UVB response line (irCHAL). In a microcosm experiment with a synthetic bacterial community, Deinococcus highly colonized wild type roots under UVB exposure, but not the isogenic lines impaired in UVB perception (irUVR8) and response (irCHAL). In a consecutive study, I addressed the current agricultural dilemma and long festering problem of monoculture practice and fungal outbreaks. The continuous usage of a field plot in N. attenuata’s native habitat using an agricultural set-up for the past 15 years led to the emergence of sudden wilt disease caused by fungal pathogen Fusarium and Alternaria disease complex. Sudden wilt disease is characterized by sudden collapse of the vascular system associated with roots turning black. Three different strategies such as microbial biocontrol, chemical fungicide and soil amendment were tested under field conditions. Among 7 different treatments, only bacterial consortia protected the plant from sudden wilt disease in 2013 field trial. In the consecutive year field trial 2014, bacterial consortia attenuated the sudden wilt disease, demonstrating the robustness of the protection effect. Bacterial protection effect is independent of genotypes and does not influence ecological traits of N. attenuata. Furthermore, bacterial consortia can be re-isolated from previously bacterial inoculated healthy plants indicating that these native consortia are excellent root colonizers. In conclusion, this work demonstrates that N. attenuata’s microbiome is not significantly sculpted by JA, plant developmental stages and soil types, whereas, tissue types and UVB supplementation influence it. In addition, this thesis addresses the importance of poly-microbial solutions to enhance the plants’ tolerance against poly-microbial disease complexes in an agricultural context; and it delineates the functional and ecological role of procurement of microbial communities by plants during germination

Integrated nematode management

This book outlines the economic importance of specific plant parasitic nematode problems on the major food and industrial crops and presents the state-of-the-art management strategies that have been developed to reduce specific nematode impacts and outlines their limitations. Case studies to illustrate nematode impact in the field are presented and future changes in nematode disease pressure that might develop as a result of climate change and new cropping systems are discussed.illustrato