bluuebunny/crossref_metadata_2025_split huggingface dataset:
Maize Rabl7 overexpression in Arabidopsis plants promotes osmotic stress tolerance
Authors: FIGUERAS M , PUJAL J , SALEH A , SAVE R , PAGES M , GODAY A 
Published: July 2006

SummaryRabl7 is a Late Embryogenesis Abundant (LEA) protein from maize, which accumulates largely during embryogenesis and also in vegetative tissues when subjected to stress conditions. We have analysed the effect of Rab 17 expression under a constitutive promoter in vegetative tissues of transgenic Arabidopsis thaliana plants. These transgenic plants have higher sugar and proline contents, and also higher water loss rate under water stress. In addition, these plants are more tolerant than non‐transformed controls to high salinity and recover faster from mannitol treatment. Our results point to a protective effect of Rabl7 protein in vegetative tissues under osmotic stress conditions.
Understanding down‐regulation of photosynthesis under water stress: future prospects and searching for physiological tools for irrigation management
Authors: FLEXAS JAUME , BOTA JOSEFINA , CIFRE JOSEP , MARIANO ESCALONA JOSÉ , GALMÉS JERONI , GULÍAS JAVIER , LEFI EL‐KADRI , FLORINDA MARTÍNEZ‐CAÑELLAS SARA , TERESA MORENO MARÍA , RIBAS‐CARBÓ MIQUEL , RIERA DIEGO , SAMPOL BARTOLOMÉ , MEDRANO HIPÓLITO 
Published: July 2006

AbstractPhotosynthetic down‐regulation and/or inhibition under water stress conditions are determinants for plant growth, survival and yield in drought‐prone areas. Current knowledge about the sequence of metabolic events that leads to complete inhibition of photosynthesis under severe water stress is reviewed. An analysis of published data reveals that a key regulatory role for Rubisco in photosynthesis is improbable under water stress conditions. By contrast, the little data available for other Calvin cycle enzymes suggest the possibility of a key regulatory role for some enzymes involved in the regeneration of RuBP. There are insufficient data to determine the role of photophosphorylation.Several important gaps in our knowledge of this field are highlighted. The most important is the remarkable scarcity of data about the regulation/inhibition of photosynthetic enzymes other than Rubisco under water stress. Consequently, new experiments are urgently needed to improve our current understanding of photosynthetic down‐regulation under water stress. A second gap is the lack of knowledge of photosynthetic recovery after irrigation of plants which have been subjected to different stages of water stress. This knowledge is necessary in order to match physiological down‐regulation by water stress with controlled irrigation programmes.
Production of monoclonal antibodies to Tomato leaf curl Bangalore virus
Authors: DEVARAJA By , GANGATIRKAR PRADNYA , SUNITHA S N , NARAYANASWAMY KIRTHI , KARANDE ANJALI , MUNIYAPPA V , SAVITHRI H S 
Published: July 2006

SummaryPurified Tomato leaf curl Bangalore virus (ToLCBV) was injected into mice and the splenocytes were used for establishing hybridoma lines. Initial screening of culture supernatants showed that 13 lines produced antibody, and after further screening four produced functional monoclonal antibodies. Upon characterisation, these were found to be of low affinity, probably due to host protein contamination and poor yield of native virus in the original preparations. In order to circumvent these problems, the coat protein of ToLCBV was over‐expressed in Escherichia coli. Fusion experiments using recombinant coat protein as antigen yielded two primary hybridoma clones G11 and E4 that exhibited good affinity of binding to the antigen. Sub‐cloning yielded four monoclonal antibodies G11E7E7, G11E7G12, E4E2 and E4G6. G11E7E7 and G11E7G12 successfully detected ToLCBV in infected leaf extracts of tomato and Nicotiana benthamiana, viruliferous whiteflies and weed samples. These monoclonal antibodies could also detect other type III geminiviruses such as Pumpkin yellow vein mosaic virus and Bhendi yellow vein mosaic virus. Thus these monoclonal antibodies can be used for testing field‐collected samples.
The incidence and distribution of viruses infecting lettuce, cultivated Brassica and associated natural vegetation in Spain
Authors: MORENO A , De BLAS C , BIURRUN R , NEBREDA M , PALACIOS I , DUQUE M , FERERES A 
Published: July 2006

SummaryA virus survey was conducted during the spring and autumn of 2001 and 2002 to determine the presence, prevalence and distribution in Spain of the viruses that are most commonly found infecting lettuce and Brassica worldwide. Crop plants showing virus symptoms from the principal lettuce and Brassica‐growing regions of Spain, and some samples of the annual and perennial flora nearby, were tested by enzyme‐linked immunosorbent assays using specific commercial antibodies against the following viruses: Alfalfa mosaic virus (AMV), Broad bean wilt virus 1 (BBWV‐1), Beet western yellows virus (BWYV), Cauliflower mosaic virus (CaMV), Cucumber mosaic virus (CMV), Lettuce mosaic virus (LMV), Pea seed‐borne mosaic virus (PSbMV), Turnip mosaic virus (TuMV) and Tomato spotted wilt virus (TSWV). Samples were also tested with a Potyvirus genus antibody. Virus incidence was much lower in spring than in autumn, especially in 2001. In spring 2002, CMV and LMV were the most prevalent viruses in lettuce, while CaMV was the most important virus present in Brassica crops grown in Navarra, followed by CMV and BWYV. In the autumn, the spectrum of viruses was different; potyviruses were widespread in lettuce grown in Madrid, but TSWV and BWYV were predominant in the Murcia region. The prevalent Potyvirus detected in lettuce fields was LMV, but none of the samples collected were positive for PSbMV or TuMV. In Brassica crops, TSWV was the most abundant in autumn‐sown crops, especially in the Navarra region. All of the viruses present in lettuce and Brassica were also frequently detected in their associated natural vegetation at the same time, suggesting that they probably play an important role as virus reservoirs. Sonchus spp. were particularly common and were frequently infected with CMV, LMV and BWYV. Another common species, Chenopodium album, was often infected with TSWV and BWYV. Multiple infections were common, especially in non‐crop plants, and the most common combination was BWYV and TSWV. The role of weeds in the epidemiology of viruses that infect lettuce and Brassica crops in Spain is discussed.
Potato virus Y reduction by straw mulch in organic potatoes
Authors: SAUCKE H , DÖRING T F 
Published: July 2006

Summary Potato virus Y (PVY) is transmitted non‐persistently by winged morphs of many aphid species and is a major problem in seed potato production. In order to evaluate the potential of straw mulch applications (4–5 t ha−1) and presprouting on PVY reduction, small scale organically managed field experiments were carried out in Northern Hessen, Germany, over 3 yr. In all years mulching significantly reduced aphid infestation on leaves as well as PVY incidence in tubers. For the effect of presprouting the temporal coincidence of two factors was crucial – crop emergence and aphid flight activity. Presprouting decreased PVY incidence when in the phase of early crop emergence aphid spring flight activity was low, but increased it, although not significantly, when prominent aphid flight peaks occurred in this critical period. Straw mulch was most effective when vector pressure was concentrated early in the year acting as a PVY protectant for young plants. In later growth stages its effect declined gradually with increasing ground coverage of the crop. Combined mulching and presprouting had a synergistic, complementary effect on reduction of PVY incidence. In an on‐farm experiment in 2001 scaling up the area mulched stepwise from 100 m2 to 900 m2 consistently kept aphid infestation at reduced levels.
Fertility table and rate of population growth of the predator Supputius cincticeps (Heteroptera: Pentatomidae) on one plant of Eucalyptus cloeziana in the field
Authors: COLA ZANUNCIO JOSÉ , CHRYSLEY LACERDA MÁBIO , SALAZAR ZANUNCIO JUNIOR JOSÉ , VINHA ZANUNCIO TERESINHA , MARIA CAMÊLO DA SILVA ANA , CURITIBA ESPINDULA MARCELO 
Published: July 2006

SummaryThe reproductive potential and population growth (rm and λ) of the predator Supputius cincticeps (Heteroptera: Pentatomidae) were evaluated using a life and fertility table. S. cincticeps was reared on one plant of Eucalyptus cloeziana in the field and fed with Tenebrio molitor (Coleoptera: Tenebrionidae) pupae. Females of this predator had a net reproductive rate (R0) of 21.02 females/female; an intrinsic rate of population increase (rm) of 0.041 and finite rate of increase (λ) of 1.042. This resulted in population growth of S. cincticeps in the eucalyptus plant with a doubling time of 17.01 days. This natural enemy can be reared under field conditions with alternative prey for use in biological control. Such individuals of S. cinticeps will be better adapted to field conditions when they are liberated.
Prospects for genetically modified crops
Authors: HALFORD NIGEL G 
Published: July 2006

SummaryGenetically modified (GM) crops have been in use commercially around the world for almost a decade. This review covers the successes and failures of GM crop varieties in that time, the current status of GM crop adoption and the traits that are being used. It also describes some of the GM crops that might come on to the market in the next decade. The barriers in the way of GM crop development in Europe, including consumer hostility, the difficulty in gaining official approval and discriminatory labelling laws are discussed.
Studies on the physiological effects of viruses on sweet potato yield in Kenya
Authors: NJERU R W , MBURU M W K , CHERAMGOI E , GIBSON R W , KIBURI Z M , OBUDHO E , YOBERA D 
Published: July 2006

SummaryExperiments to determine the effect of the three viruses most common on Kenyan sweet potato varieties were carried out at the University of Nairobi Kabete farm. The sweet potato varieties were Bungoma, Kemb 10 and Ex‐Shimba hills which were either virus‐free or infected with Sweet potato feathery mottle virus (SPFMV), Sweet potato mild mottle virus (SPMMV), Sweet potato chlorotic stunt virus (SPCSV) or a combination of SPFMV and SPCSV. Canopy photosynthetically active radiation (PAR) interception and the relative chlorophyll content of the plants were determined. At harvest, marketable tuber yield, harvest index (HI), leaf area index (LAI) and specific leaf weight (SLW) were measured.Infection with single viruses caused no or mild symptoms and had no significant effect on chlorophyll content of leaves of any variety. Dual infection with SPFMV and SPCSV resulted in severe symptoms characteristic of sweet potato virus disease complex (SPVD) and significantly reduced chlorophyll content. Only SPCSV and SPCSV + SPFMV reduced PAR interception, the latter combination especially. Generally, infection with single viruses increased the SLW but a decrease occurred in plants dually infected with SPFMV and SPCSV. Whereas SPVD significantly reduced the harvest index (78%) and tuber yield (98%) in the three varieties, infection with single viruses caused a reduction only in the varieties Bungoma and Kemb 10. SPVD reduced yield through reducing leaf chlorophyll content, PAR interception, LAI and HI. The single virus infections possibly reduced assimilate translocation from leaves to tubers as is inferred from high SLW. Effects of viruses on physiological processes and yield are discussed.
A field trial to assess the effects of rabbit grazing on spring barley
Authors: DENDY JULIE , MCKILLOP GORDON , FOX SUE , WESTERN GAVIN , LANGTON STEVE 
Published: July 2006

SummarySpring barley is widely grown throughout the UK and significant yield loss can occur as a result of rabbit grazing. In a 3‐yr trial, spring barley was grown in six enclosures following current agronomic procedures and was subjected to grazing by different population densities of rabbits. The annual yield loss at the end of the trial was 0.5% rabbit−1 ha−1. The yield loss per rabbit was calculated to be around 25 kg and the financial loss was calculated as £2.00 per rabbit at 1998 prices (approx. £80 tonne−1). Models allowing farmers to predict the levels and costs of damage by rabbits to winter wheat and for silage have already been developed. The results from this trial enable farmers to extend their predictions to include spring barley. The implications for this are discussed.
Instrumental test to estimate a model of forecast yield: a non‐parametric application to the pollen index in South Italy
Authors: ORLANDI F , LANART D , PIERONP L , ROMANO B , FORNACIARI M 
Published: July 2006

SummaryA statistical test is described to verify the characteristics of the biological information contained in the dynamics of the flowering process. The test focuses on interactions between the pollen index and climatic variables to investigate if the biological indicator can synthesise the information of the pre‐flowering phases.The multiple‐regression model is built upon two pre‐flowering climate macro‐indicators extracted by Principal Component Analysis (PCA) and the optimised pollen index is obtained by non‐parametric estimation.The empirical analysis is applied to 15 stations located in southern Italy in regions that have a longstanding tradition of olive production. Using the variance explained, we find that an optimised pollen index is fairly well predicted by the pre‐flowering climatic data. We conclude that the optimised pollen index makes more parsimonious the modelling for predicting olive production.
Number of genes controlling slow rusting resistance to leaf rust in five spring wheat cultivars
Authors: DAS M K , RAJARAM S , MUNDT C C , KRONSTAD W E 
Published: July 2006

SummaryThe number of genes controlling slow rusting resistance to leaf rust (Puccinia triticina) was estimated in five spring wheat (Triticum aestivum) cultivars using quantitative formulae. Parents and F6 families were evaluated in replicated field trials under epidemics initiated by artificial inoculation. The F6 families resulted from a diallel cross involving the fast‐rusting cultivar Yecora 70 and five slow‐rusting wheat cultivars: Sonoita 81, Tanager ‘S’, Galvez 87, Ures 81, and Moncho ‘S’. The area under the disease progress curve (AUDPC) was used to measure leaf rust severity over time. Results indicate that cultivar Sonoita 81 has three or four genes, Tanager ‘S’ has two or three genes, Galvez 87 has three genes, and both Ures 81 and Moncho ‘S’ have two genes for slow rusting resistance to leaf rust. Based on this result and previously reported moderate to high narrow‐sense heritability estimates for slow rusting resistance in these materials, early‐generation selection for slow leaf rusting would be effective.
Fast accumulation of few polyhedra mutants during passage of a Spodoptera frugiperda multicapsid nucleopolyhedrovirus (Baculoviridae) in Sf9 cell cultures
Authors: REGINA DA SILVA PEDRINT MÁRCIA , LUIZ CALDAS WOLFF JOSÉ , REID STEVE 
Published: July 2006

SummaryBaculoviruses are a group of viruses that infect invertebrates and that have been used worldwide as a biopesticide against several insect pests of the Order Lepidoptera. In Brazil, the baculovirus Spodoptera frugiperda multicapsid nucleopolyhedrovirus (SfMNPV; Baculoviridae) has been used experimentally to control S. frugiperda (Lepidoptera: Noctuidae), an important insect pest of corn (maize) fields and other crops. Baculoviruses can be produced either in insect larvae or in cell culture bioreactors. A major limitation to the in vitro production of baculoviruses is the rapid generation of mutants when the virus undergoes passages in cell culture. In order to evaluate the potential of in vitro methods of producing SfMNPV on a large‐scale, we have multiplied a Brazilian isolate of this virus in cell culture. Extensive formation of few polyhedra mutants was observed after only two passages in Sf9 cells.
Flow cytometric analysis for ploidy level differentiation of 45 hairy vetch accessions
Authors: YEATER KATHLEEN M , BOLLERO GERMAN A , BULLOCK DONALD G , RAYBURN A LANE 
Published: July 2006

SummaryDetermining the ploidy of plant germplasm is a necessary step in breeding or genetic studies in species. The purpose of this research was to determine the presence of ploidy level differentiation of hairy vetch (Vicia villosd) germplasm. Flow cytometry and root tip chromosome squashing methods were employed to assess 45 accessions labeled V. villosa available through the USDA germplasm collection. Flow cytometry determined that 43 of the accessions were 2C, one accession was 4C, and one accession was 6C. Analysis of accessions by root tip chromosome counts indicated that all accessions were diploid. The 2C accession contains 14 chromosomes and their chromosomes were approximately one‐half and one‐third in size as compared to the chromosomes of the 4C and 6C accessions, respectively. The 4C accession was observed to have 16 chromosomes and the 6C accession was observed to have 14 chromosomes. The large‐scale differences in DNA amounts were due to chromosomal size variability as opposed to ploidy differences. This revealed the incidence of species misidentification of these two V. villosa accessions to be Vicia pannonica. All the V. villosa accessions were observed to be diploid and have similar DNA amounts. Flow cytometry proved to be useful in the efficient assessment of these accessions.
Control of potato cyst nematodes and economic benefits of application of 1,3‐dichloropropene and granular nematicides
Authors: MINNIS S T , HAYDOCK P P J , EVANS K 
Published: July 2006

SummaryThe two species of the potato cyst nematodes (PCN) Globodera pallida and G rostochiensis are the most problematic pests of the potato crop in the UK. There are no commercially available cultivars with full resistance to G. pallida and both crop rotation and granular nematicides are less effective at controlling this species than G. rostochiensis. In situations of very high PCN levels it may be possible to reduce populations and yield losses by using an autumn application of the soil fumigant 1,3‐dichloropropene (1,3‐D) followed by a spring application of a granular nematicide. Two field experiments were done to look at the integration of methods for the control of PCN. The Common Field experiment (G. rostochiensis infested) compared the use of 1,3‐D with the granular nematicides aldicarb, oxamyl and fosthiazate when growing the susceptible cv. Estima. The Four Gates experiment (infested with both PCN species but mainly G rostochiensis) compared the performance of cv. Santé (partially resistant to G. pallida, fully resistant to G. rostochiensis) with that of the susceptible cv. Estima when treated with 1,3‐D and oxamyl at full and half‐rates. The results of the experiments show that an integrated approach to nematode control on heavily infested sites, including granular and fumigant nematicides and cultivar resistance, can lead to significant decreases in nematode population densities and reduce yield losses. An economic evaluation of the experiments modelled the gross margins from the different nematicide treatments. In Common Field, the highest gross margins were achieved with the combined use of fumigant and granular nematicides. In Four Gates, there was a clear economic benefit for both cultivars from the use of 1,3‐D. In this experiment, oxamyl was of economic value to Estima but not to Sante and full‐rate oxamyl was of more benefit than half‐rate to Estima.
Spatial and temporal patterns of abundance of the potato leafhopper among red maples
Authors: BENTZ J , TOWNSEND A M 
Published: July 2006

SummaryA study was conducted in the 2001 growing season to examine the relative abundance, dispersion and distribution of the potato leafhopper (Empoasca fabae) among trees of 24 red maple (Acer rubrum) clonal selections. Yellow sticky traps hung from the trees were used to estimate the relative number of aerial potato leafhoppers among trees, starting on 1 May 2001 and stopping on 4 September 2001. More insects were collected from the east side of the plot than from the other sides in May, but no differences were significant late in the season. Few leafhoppers were collected during May, but the number of leafhoppers collected on traps rapidly increased and peaked during June. Afterwards, populations decreased and just a few individuals were trapped late in the season. Overall, significantly more leafhoppers were caught on traps hanging from trees of clone 56026 and 55410 than on trees of the other clones. Dispersion of the potato leafhopper changed from being aggregated in May, to being random in August, and also differed among the different clones. Populations tended to aggregate with increases in population numbers. Positive significant autocorrelations were detected at short distances in May, suggesting an aggregated spatial pattern early in the season. Yet, different autocorrelation patterns were detected within each block later in the season. Our results indicate that management practices could be developed to minimise pesticide use by targeting smaller areas with the highest populations at the right time of the season.
Occurrence and distribution of cassava begomoviruses in Kenya
Authors: WERE H K , WINTER S , MAISS E 
Published: July 2006

SummaryA survey for cassava mosaic disease (CMD) was conducted in Kenya, to investigate the factors contributing to the generally increased incidence and severity of CMD in the cassava growing regions and to study the distribution of the disease's causal begomoviruses, African cassava mosaic virus (ACMV) and East African cassava mosaic virus (EACMV) and their strains. Special emphasis was given to the occurrence of the destructive recombinant Uganda variant strain of EACMV (EACMV‐UG2). Samples from 91 farmers' fields in the main cassava‐growing areas of coastal and western Kenya were collected and subjected to ELISA and PCR for detection and typing of the begomoviruses present. CMD incidence was highest in western Kenya (80–100%) and lowest in the Coast province (25–50%). In Western and Nyanza provinces, 52% of the samples tested contained EACMV‐UG2, 22% ACMV and 17% contained both ACMV and EACMV‐UG2. EACMV was found in four cases at different sites. In cassava samples from the coast province, only EACMV with DNA‐A sequences similar to EACMV strains present in Kenya and Tanzania was found. East African cassava mosaic Zanzibar virus (EACMZV) was present in several farms in the Kilifi district. In 15% of all cassava samples with CMD symptoms, flexuous, filamentous virus‐like particles were also found, providing evidence for a more complex virus situation in cassava grown at the Kenyan coast. In western Kenya, where intense cassava cultivation takes place, CMD is rampant and EACMV‐UG2 was found in mixed virus infections with ACMV driving the epidemics. In coastal areas, where farms are scattered and in isolation, EACMV is endemic, however, with a lower disease incidence and with a limited impact to cassava production.