bluuebunny/crossref_metadata_2025_split huggingface dataset:
The influence of temperature on the susceptibility of vine weevil, Otiorhynchus sulcatus (Fabricius) (Coleoptera: Curculionidae), larvae to Metarhizium anisopliae (Deuteromycotina: Hyphomycetes)
Authors: MOORHOUSE E R , GILLESPIE A T , CHARNLEY A K 
Published: February 2008

SummaryMortality of Otiorhynchus sulcatus (Fabricius) larvae at 10oC, 15oC, 20oC and 25oC following treatment with 107conidia ml“1suspensions of six Metarhizium anisopliae (Metschnikoff) Sorokin isolates was temperature dependent. In all cases, the LT50s were inversely related to temperature, but the nature of this response varied between isolates. Strain 101‐82 was the most virulent isolate at 25oC with an LT50 of 3.7 days, but it was the least virulent isolate at 15oC and it failed to kill any O. sulcatus larvae at 10oC. In contrast, strain 159‐83 had the lowest virulence at both 20oC and 25oC, whereas it was the most virulent isolate at 10oC with an LT50 of 20.0 days. The mortality rates followed a similar pattern and were positively related to temperature in all cases with the exception of strain 159‐83 at 25oC. Mycosis development was examined on larvae treated with strain 275‐86 and significant differences were obtained between all four temperatures. Sporulation commenced after approximately 2.75 days at 25oC, but took nearly 11 days at 10oC. The infection rates also varied between temperatures; sporulation occurred on 98% of the treated larvae at 25oC, but only on 93%, 87% and 49% of the larvae at 20oC, 15oC and 10oC, respectively. The results of these bioassays demonstrate that temperature has a significant effect on the virulence of M. anisopliae. The differences between fungal strains also emphasises the importance of selecting isolates for specific situations on the basis of their temperature profiles.
Controlling potato tuber blemish diseases on cv. Estima with chemical and non‐chemical methods
Authors: HIDE G A , BOORER KATHRYN J , HALL SHARON M 
Published: February 2008

SummaryIn 3 years, seed tubers were treated or not with imazalil in March or April, sprouted and planted in field experiments. Tubers were harvested on several dates and cured under different conditions for 2 wk, or not cured, before storage for 6 months. In some years effects of irrigation, seed tuber size and seed stock were tested.Fungicide seed treatment decreased silver scurf, and was most effective in 1989 when the seed had little infection and the season was dry, but the treatment increased black dot. Silver scurf and black dot were decreased by harvesting early and also by drying tubers before storage (dry curing), and these practices also sometimes decreased black scurf and skin spot. The effects of fungicide seed treatment and of dry curing were greater the earlier the tubers were harvested. Irrigation decreased silver scurf and in one year decreased black scurf but greatly increased black dot. Silver scurf, black dot and skin spot were more common on tubers from large than small seed whereas black scurf was most common on tubers from small seed.In 2 years tubers were affected with a brown superficial blemish (golding blotch). This developed on the undersides of tubers in soil and was decreased by irrigation. Its cause is not known.
Sitona weevils (Coleoptera: Curculionidae) as agents for rapid transfer of nitrogen from white clover (Trifolium repens L.) to perennial ryegrass (Lolium perenne L.)
Authors: MURRAY P J , HATCH D J 
Published: February 2008

SummaryThe effects of root feeding by larvae of Sitona hispidulus (F.) (a common weevil pest of white clover) on the rate of transfer of nitrogen between plants of white clover (Trifolium repens L.) and perennial ryegrass (Lolium perenne L.) were investigated using a nutrient slant board technique. Clover plants, labelled with 15N were grown adjacent to ryegrass plants and were either infested with Sitona larvae or not infested. Ryegrass plants associated with the infested clover plants had a significantly higher dry matter yield and nitrogen content (75% and 74% respectively) than the uninvested plants, after 33 days exposure to insect herbivory. It was concluded that root feeding insects could play an important role in the cycling of nitrogen in grass/clover swards.
Movement of barley mild mosaic and barley yellow mosaic viruses in leaves and roots of barley
Authors: SCHENK P M. , ANTONIW J F. , BATISTA M deF , JACOBI V. , ADAMS M J. , STEINBISS H H. 
Published: February 2008

SUMMARYLeaves of barley plants were mechanically inoculated with barley mild mosaic virus (BaMMV) and roots were inoculated using viruliferous zoospores of the fungus vector Polymyxa graminis. At intervals after inoculation, leaves and roots were tested by different methods to detect virus coat protein (ELISA or Western blot) or nucleic acid (slot‐blot or reverse transcriptase‐PCR). Following inoculation with zoospores, virus could be detected in roots after 1 wk (Western blot or PCR) but not until 3–4 wk by ELISA. Virus moved to leaves in 5–6 wk but, except at temperatures of about 20°C, plants had to be cut back close to soil level to stimulate virus movement. Following mechanical inoculation, virus could be detected in leaves of a susceptible cultivar within 5 days by ELISA and 3 days by the other methods. Western blots and PCR showed that virus was present in the roots by 5 days. BaMMV was not detected by any method in leaves or roots of a resistant cultivar, indicating that the virus did not multiply in it. When leaves were mechanically inoculated on a small area only, BaMMV capsid protein was detected below the inoculated site at 4 days and in young growing leaves and roots at 13 days after inoculation but never above the inoculation site or in older leaves. After stem extension began, new leaves of infected plants were free of symptoms. The results are compared to observations of plants infected with barley yellow mosaic virus (BaYMV). It is proposed that movement of BaMMV and BaYMV is strongly related to the phloem transport and to the source‐sink pattern of winter barley plants.
Evaluation of an enzyme‐linked immunosorbent assay for detection of Mycosphaerella pinodes in pea seeds
Authors: Faris‐Mokaiesh S. , Corbiere R. , Lyons N F. , Spire D. 
Published: February 2008

SummaryA polyclonal antiserum was raised against soluble mycelial extracts of Mycosphaerella pinodes aiming at pathogen detection in infected pea seeds by ELISA. When tested against the homologous antigen, it allowed the detection of 5 ng fungal soluble protein ml‐1 buffer, by double‐antibody sandwich ELISA (DAS‐ELISA). Positive reactions were obtained with isolates of M. pinodes of wide geographical origins but also with all tested isolates of Ascochyta pisi and Phoma medicaginis var. pinodella, two closely related pathogens forming with the target organism the Ascochyta complex. Out of the 11 other genera of pea seed‐borne fungi tested, only two (Alternaria sp. and Stemphylium sp.) cross‐reacted strongly by both antigen‐coated plate (ACP‐ELISA) and DAS‐ELISA. Cross‐absorption of the crude antiserum could not lead to a species‐specific antiserum; however, a combination of P. medicaginis var. pinodella and Stemphylium sp. antigens resulted in an antiserum preferentially recognising A. pisi and M. pinodes. The cross‐absorbed antiserum detected 50 and 500 ng of fungal protein ml‐1 buffer and healthy seed extracts respectively. DAS‐ELISA proved suitable for the detection and quantification of M. pinodes in infected pea seeds tested singly.
The effect on yield in courgette and marrow of the mild strain of zucchini yellow mosaic virus used for cross‐protection
Authors: SPENCE N J , MEAD A. , MILLER A. , SHAW E D , WALKEY D G A 
Published: February 2008

Summary.The effects on yield in courgette and marrow (Cucurbita pepo) crops resulting from inoculation with the mild strain of zucchini yellow mosaic virus (ZYMV:WK), have been determined in polythene‐house trials and in three years of outdoor, commercial field trials. In polythene‐house trials ZYMV:WK inoculated plants were up to 10 days later in flowering than uninoculated plants and their cumulative yields were between 5% and 26% less than uninoculated plants depending on the cultivar. In most field trials cumulative yields from inoculated plants were between 4% and 38% less than uninoculated plants depending on the site and cultivar, but in one trial the yield was 7% higher from inoculated plants. In all experiments, courgette and marrow fruits harvested from ZYMV:WK inoculated plants were symptomless and indistinguishable from fruit harvested from uninoculated plants. The mild leaf symptoms induced by ZYMV:WK infection did not intensify to severe leaf symptoms and where there were natural outbreaks of severe ZYMV infection, fruits from inoculated plants remained symptomless whilst those from uninoculated plants were severely affected and unmarketable.
Gene transfer between canola (Brassica napus L. and B. campestris L.) and related weed species
Authors: BROWN JACK , BROWN ANGELA P 
Published: February 2008

Summary. Brassica species are particularly receptive to gene transformation techniques. There now exists canola genotypes with transgenic herbicide resistance for glyphosate, imidazolinone, sulfonylurea and glufosinate herbicides. The main concern of introducing such herbicide resistance into commercial agriculture is the introgression of the engineered gene to related weed species. The potential of gene transfer between canola (Brassica napus and B. campestris) and related weed species was determined by hand pollination under controlled greenhouse conditions. Canola was used as both male and female parent in crosses to the related weed species collected in the Inland Northwest region of the United States. Weed species used included: field mustard (B. rapa), wild mustard (S. arvensis) and black mustard (B. nigra). Biological and cytological aspects necessary for successful hybrid seed production were investigated including: pollen germination on the stigma; pollen tube growth down the style; attraction of pollen tubes to the ovule; ovule fertilisation; embryo and endosperm developmental stages. Pollen germination was observed in all 25 hybrid combinations. Pollen tubes were found in the ovary of over 80% of combinations. About 30% of the hybrid combinations developed to the heart stage of embryo development or further. In an additional study involving transgenic glufosinate herbicide resistant B. napus and field mustard it was found that hybrids occurred with relatively high frequency, hybrids exhibited glufosinate herbicide resistance and a small proportion of hybrids produced self fertile seeds. These fertile plants were found to backcross to either canola or weed parent.
Field and laboratory studies on the effects of temperature on the development of the carrot fly (Psila rosae F.)
Authors: COLLIER ROSEMARY H. , FINCH STAN 
Published: February 2008

SummaryThe thermal requirements for the pre‐oviposition period, egg, larval, pupal and adult stages of the carrot fly were measured under field conditions and at a range of constant temperatures in the laboratory.In the laboratory, the pre‐oviposition period lasted from 4 days at 24oC to 28 days at 9oC. In general, female carrot flies laid about 20–40 eggs in each batch. Once the first eggs had been laid, subsequent batches were laid after an average of 3 days at 24oC to 7 days at 11.5oC. The numbers of days required for egg, larval and pupal development ranged from 5, 31 and 24 days respectively at 21.5oC to 25, 145 and 84 days respectively at 9oC. Under laboratory conditions, complete development from egg to adult required from 60 days at 21.5oC to 254 days at 9oC.Newly‐formed carrot fly pupae were exposed to temperatures of 22–30oC for various 5–10 day periods during pupal development. Exposure to temperatures of 24oC and 26oC caused some, and exposure to 28oC and 30oC caused all, of the pupae to delay development. Pupae were sensitive to high temperatures only for approximately 4–10 days after pupation.Under field conditions between mid‐May and early September, full carrot fly development (egg‐adult) took 84–100 days. The numbers of day‐degrees required (base temperatures of 2oC and 4oC) for carrot fly development in the laboratory and in the field were similar for egg hatching but not for the pre‐oviposition period or for egg‐adult development. The thermal requirement for fly development in the field varied between inoculation dates, fewest day‐degrees being required when development was rapid.
Selection of Cassida spp. from southern Africa for the biological control of Chrysanthemoides monilifera in Australia
Authors: KLEINJAN C A. , SCOTT J K. 
Published: February 2008

SummaryFour species of tortoise beetle (Chrysomelidae, Cassidinae)(Cassida spatiosaSpaeth and three undescribedCassidaspecies, labelled 1. 2 and 3) from South Africa, were assessed as potential biological control agents againstChrysanthemoides monilifera monilifera(L.) T. Norl. andC. m. rotundata(DC.) T. Norl. These southern African plants are important weeds of conservation areas in Australia. In South Africa,Cassida spatiosawas found feeding onC monilifera subcanescens(DC.) T. Norl.,Cassidasp. 1 onChrysanthemoides monilifera pisifera(L.) T. Norl. andC m. monilifera, Cassidasp. 2 onC m. pisiferaandChrysanthemoides incana(Burm.f.) T. Norl. andCassidasp. 3 on C.m. rotundata.The life cycle of each species was completed in about three months on the leaves of the host.Cassidaspecies 1, 2 and 3 were tested against eight species of plant and only fed and completed development onChrysanthemoidesspecies and the related species.Calendula officinalisL.Cassidaspecies 1 and 3 showed no preference betweenCalendula officinalisandChrysanthemoidesspecies for oviposition.Cassidaspecies 3 was selected for further assessment as a biological control agent based on match to the host subspecies and target climate in Australia.
Ribes host range and erratic distribution within plants of blackcurrant reversion associated virus provide further evidence for its role as the causal agent of reversion disease
Authors: LATVALA SATU , SUSI PETRI , LEMMETTY ANNE , COX SARAH , JONES A TEIFION , LEHTO KIRSI 
Published: February 2008

SummaryReversion is the most important disease of blackcurrant crops world‐wide yet, despite research over more than 70 yr, the causal agent of this disease has not been identified. We reported recently the isolation of a new virus from reverted blackcurrant which had a very close association with the two recognised forms of blackcurrant reversion disease, and was detected in vector gall mites from reverted plants and in plants on which such mites had fed (Lemmetty et al., 1997). These data suggest that this virus, tentatively called blackcurrant reversion associated virus (BRAV), may be the causal agent of reversion disease. We now report the detection of BRAV by immuno‐capture reverse‐transcriptase PCR (IC‐RT‐PCR) in redcurrant and in the wild species, Ribes spicatum and R. alpinum, other known hosts of the reversion agent, but not in the non‐host, gooseberry, graft‐inoculated with scions from reverted blackcurrant plants. We also demonstrate the erratic distribution of BRAV in reversion‐affected blackcurrant plants, another characteristic of the reversion agent. Taken together with our earlier findings, these new data add further support to the suggestion that BRAV is the causal agent of reversion disease. We also report how changes to the various parameters of sample preparation and of the IC‐RT‐PCR protocol affect the sensitivity of BRAV detection.
Toxicity of anethole and its effects on egg production of Ceratitis capitata Wied. (Dipt., tephritidae)
Authors: BAZZONI EMANUELA , PASSINO GIOVANNI SANNA , MORETTI MARIO D L , PROTA ROMOLO 
Published: February 2008

SummaryWe report the effects of anethole on adult Ceratitis capitata Wied. (Diptera, Tephritidae) which cause serious damage to fruit crops. Because of the toxicological and environmental pollution due to the indiscriminate use of organophosphates against the endophagous larvae, the control of this pest is now mainly directed against the adults, by the application of bait sprays. Considerable toxic effects have been obtained by oral administration to adults of nutritive formulations containing 5% anethole with some hydrolised commercial proteins. In this test we observed high values of mortality (85% after 24 h) and a total inhibition of reproductive activity. The toxic effect produced by oral administration of the compound tested appears to be correlated to irreversible damage to the gut of the medfly.These results acquire a particular importance in view of the introduction of alternative methods for the control of the medfly. In particular, our objective is the testing of relevant formulations of this active principle in field. The use of anethole combined with protein baits, which can be used in the open field, is therefore particularly promising.
Detection and differentiation of African coconut phytoplasmas: RFLP analysis of PCR‐amplified 16S rDNA and DNA hybridisation
Authors: TYMON A M. , JONES P. , HARRISON N A. 
Published: February 2008

SummaryPhytoplasmas associated with lethal decline diseases of the coconut palm (Cocos nucifera) in west and east Africa were detected by the specific amplification of their 16S rRNA genes. The primers used were based on conserved mollicute‐specific and coconut‐phytoplasma 16S rRNA gene sequences. Phytoplasma 16S rDNA was amplified from all African decline affected palms, some periwinkle maintained phytoplasmas, but not from healthy palms, infected palms from Florida or from the Cocos spiroplasma and Acholeplasma sp. mollicutes. African phytoplasmas were also detected by DNA hybridisation using two probes from the palm lethal yellowing phytoplasma from Florida. Probes hybridised at moderate stringency to dot blots of lethal decline affected palms from Africa, indicating possible genetic relationships between different coconut phytoplasmas. RFLP analysis of rDNA fragments (length c. 1.45 kbp) detected polymorphisms, indicating that the pathogens found in west and east Africa are not identical. This provides a useful tool for further epidemiological studies of African coconut phytoplasmal diseases.
An empirical method for describing the joint effects of environmental and other variables on crop yield
Authors: LARK R M. 
Published: February 2008

SummaryThere is considerable interest in developing understanding of the spatial variation of crop yield within fields in relation to the spatial variation of environmental factors. Such understanding might allow inputs to crops to be used more efficiently by spatially variable application. The joint action of factors on crop yield (whether controlled treatments or environmental variables) may be additive, interactive or potentially limiting in the sense of von Liebig's “Law of the Minimum”. The nature of the joint action of an input and environmental factors has profound implications for the possibility of improving the efficiency of use of the input by spatially variable application. Conventional methods for analysing data on such factors and yield (e.g. multiple regression) make specific assumptions compatible only with a narrow range of permissible models. A procedure is proposed and demonstrated in this paper for the exploratory analysis of data from experiments and/or crop surveys in order to describe the joint action of important factors on crop yield. The procedure could be applied to specific experiments in order to indicate whether there is any scope for optimising rates of an input with respect to one or more spatially variable factors, and for indicating whether the relationship between the local optimum rate of the input and values of these factors is simple (factors act additively or in accordance with the Law of the Minimum) or complex (factors interact).
Genetic studies on seedling vigour in sesame
Authors: MPONDA O K K. , MORSE S. , GIBBON D. , ARTHUR A E. 
Published: February 2008

SummaryGenetic studies were carried out on seedling and agronomic characters amongst 50 sesame genotypes to estimate the genetic variation, determine the relationships amongst the characters and identify rapidly growing genotypes with vigorous seedling growth. The contribution of genetic variance was highest for the two mature characters, days to first flower (95.6%) and number of nodes to first flower (95.2%), and was medium/high (50–75%) for most of the seedling characters. Strong positive genetic correlations were obtained between various cotyledon and early leaf characteristics measured at 20 days after sowing. Based on these results several genotypes were identified as having rapid seedling growth and these could form an initial gene pool to provide material for screening for tolerance to sesame flea beetle.
Resistance of tomato infected with cucumber mosaic virus satellite RNA to potato spindle tuber viroid
Authors: YANG XICAI , KANG LIANGYI , TIEN PO 
Published: February 2008

Summary.Tomato (Lycopersicon esculentum cvs Rutgers and Lichun) plants were firstly pre‐inoculated either with a cucumber mosaic virus (CMV) isolate containing satellite RNA (CMV‐S52) or with a CMV isolate without satellite RNA, and then challenged 14 days later with a severe strain of potato spindle tuber viroid (PSTVd). Also, tomato plants transformed with CMV satellite cDNA and non‐transgenic control plants were directly inoculated with PSTVd. Protection effects were assessed by the observation of symptoms and by assay of PSTVd accumulation in tomato plants using return polyacrylamide gel electrophoresis and silver staining. The results indicated that the satellite‐transgenic plants and plants pre‐inoculated with CMV‐S52 showed much milder symptoms of PSTVd infection than the respective control plants. The concentration of PSTVd RNA in the satellite‐transgenic plants and CMV‐S52 pre‐inoculated plants was reduced to about 0.02‐0.03 of the controls. PSTVd infection did not increase the amount of satellite ds‐RNA in plants. It is concluded that the plant resistance to PSTVd is induced by the presence of satellite RNA rather than the CMV infection. It is suggested that as there is considerable sequence similarity between satellite RNA and PSTVd, base pairings may be a cause of reduction of both symptoms and the accumulation of PSTVd.
Diversity in greengram (Vigna radiata (L.) Wilczek) germplasm collection and its potential use in crop improvement
Authors: BISHT I S , MAHAJAN R K , KAWALKAR T G 
Published: February 2008

SummaryGreengram or mungbean (Vigna radiata (L.) Wilczek), which originated in the Indian sub‐continent, is an important pulse crop in India. Genetic diversity and patterns of variation among 111 accessions representing the better agronomic types from the entire collection of the National Bureau of Plant Genetic Resources were studied. Wide variation in morphological and agronomic traits viz. number of pods per plant, yield per plant, 100‐seed weight, fruit setting capacity, flowering period, maturity, number of pod bearing peduncles, plant height, number of primary branches, length of branch, nodulation and leafiness was observed. Grain yield was found to be significantly correlated with 100‐seed weight and pod length. The data were subjected to cluster and principal components analysis. The accessions were grouped into six discrete and well‐defined clusters. The study demonstrated the patterns of variation at the population level. The multivariate analysis was useful in identifying a group of accessions with yield enhancing traits within a highly diverse group of accessions and their potential value in greengram improvement is suggested.