20 research outputs found
Use of planting date to avoid injury from soybean insect pests
Seedcorn maggots (SCM) and bean leafbeetles (BLB) can substantially reduce soybean grain yield in Iowa and surrounding states. SCM feed on germinating seeds and the growing tips of seedlings, resulting in reduced stands and abnormal plants. Adult bean leaf beetles feed mostly on leaves and pods, with the most serious losses caused by pod feeding. Pod lesions caused by the beetles allow excess moisture and secondary plant disease organ isms to enter the pod, causing seed shriveling and discoloration. As a result, seed weight and quality are reduced. The pod feeding problem has increased in severity since the early 1980s, making the bean leaf beetle the most economi cally important insect pest on soybeans in Iowa
Biology and Management of Bean Leaf Beetle in Soybean
The bean leaf beetle, Cerotoma trifurcata (Forster), is a widespread pest of soybean in the major crop production areas of the U.S. It has been a significant problem in the South but, until the last decade, was an infrequent problem in the Midwest. During earlier times, the major concern was early season invasion of soybean fields and localized problems of seedling defoliation. In the 1980\u27s, however, grower reports of pod feeding were received, and these have increased significantly until the present. Indeed, today the bean leaf beetle has become the most consistently important insect problem on soybean in our region. The purpose of this presentation is to update specialists on the soybean and outline a basic integrated pest management (IPM) system for the species in Iowa. To accomplish this, we will discuss foundation elements of IPM, including identification and biology, sampling for adults and pod injury, and economic thresholds. We will conclude by describing both preventive and curative tactics that can be employed to reduce losses from this growing pest problem
Soil health and sustainability: managing the biotic component of soil quality
Soil health is the capacity of soil to function as a vital living system, within ecosystem and land-use boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and promote plant and animal health. Anthropogenic reductions in soil health, and of individual components of soil quality, are a pressing ecological concern. A conference entitled âSoil Health: Managing the Biological Component of Soil Qualityâ was held was held in the USA in November 1998 to help increase awareness of the importance and utility of soil organisms as indicators of soil quality and determinants of soil health. To evaluate sustainability of agricultural practices, assessment of soil health using various indicators of soil quality is needed. Soil organism and biotic parameters (e.g. abundance, diversity, food web structure, or community stability) meet most of the five criteria for useful indicators of soil quality. Soil organisms respond sensitively to land management practices and climate. They are well correlated with beneficial soil and ecosystem functions including water storage, decomposition and nutrient cycling, detoxification of toxicants, and suppression of noxious and pathogenic organisms. Soil organisms also illustrate the chain of cause and effect that links land management decisions to ultimate productivity and health of plants and animals. Indicators must be comprehensible and useful to land managers, who are the ultimate stewards of soil quality and soil health. Visible organisms such as earthworms, insects, and molds have historically met this criterion. Finally, indicators must be easy and inexpensive to measure, but the need for knowledge of taxonomy complicates the measurement of soil organisms. Several farmer-participatory programs for managing soil quality and health have incorporated abiotic and simple biotic indicators. The challenge for the future is to develop sustainable management systems which are the vanguard of soil health; soil quality indicators are merely a means towards this end
A cross-country comparison of accommodation manager perspectives on online review manipulation
Biceps Muscle Fatty Infiltration and Atrophy. A Midterm Review After Arthroscopic Tenotomy of the Long Head of the Biceps
Foraminifera from the Lower Kimmeridgian (Platynota beds) of the Northern and Middle Franconian Alb, GermanyâFauna and Palecology
Chemotherapy-Associated Hepatotoxicity and Hepatic Resection for Metastatic Colorectal Cancer
Association of a novel functional promoter variant (rs2075533 C>T) in the apoptosis gene TNFSF8 with risk of lung cancerâa finding from Texas lung cancer genome-wide association study
Published genome-wide association studies (GWASs) have identified few variants in the known biological pathways involved in lung cancer etiology. To mine the possibly hidden causal single nucleotide polymorphisms (SNPs), we explored all SNPs in the extrinsic apoptosis pathway from our published GWAS dataset for 1154 lung cancer cases and 1137 cancer-free controls. In an initial association analysis of 611 tagSNPs in 41 apoptosis-related genes, we identified only 10 tagSNPs associated with lung cancer risk with a P value <10â2, including four tagSNPs in DAPK1 and three tagSNPs in TNFSF8. Unlike DAPK1 SNPs, TNFSF8 rs2181033 tagged other four predicted functional but untyped SNPs (rs776576, rs776577, rs31813148 and rs2075533) in the promoter region. Therefore, we further tested binding affinity of these four SNPs by performing the electrophoretic mobility shift assay. We found that only rs2075533T allele modified levels of nuclear proteins bound to DNA, leading to significantly decreased expression of luciferase reporter constructs by 5- to â10-fold in H1299, HeLa and HCT116 cell lines compared with the C allele. We also performed a replication study of the untyped rs2075533 in an independent Texas population but did not confirm the protective effect. We further performed a mini meta-analysis for SNPs of TNFSF8 obtained from other four published lung cancer GWASs with 12 â214 cases and 47â 721 controls, and we found that only rs3181366 (r2 = 0.69 with the untyped rs2075533) was associated to lung cancer risk (P = 0.008). Our findings suggest a possible role of novel TNFSF8 variants in susceptibility to lung cancer