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Cenopalpus wainsteini(Livshitz and Mitrofanov, Proceedings Nikitsky Botanic Garden 39:1–72, 1967), a mite species in the family Tenuipalpidae, was discovered on Pinus sylvestrisThumb. in Lima, Peru, and represents the first record of this species in the Americas. Previously, only Cenopalpus pulcher(Canestrini and Fanzago Acari Academia Cientifico Veneto 5:130-142, 1876) and C. officinalis(Papaioannou-Souliotis, Annals Institut Phytopathology Benaki 15:11–27, 1986) have been reported from the Nearctic and Neotropic regions. The current paper describes and illustrates the morphological characters of female, deutonymph, protonymph and includes the first description of the larval stage of the species. Species of C. wainsteinicollected in Peru were compared with specimens collected in Italy, as well as with the original description by Livschitz and Mitrofanov of specimens from Ukraine and the re-description of the species by Arabuli and Kvavadze Int J Acarology 39(7): 538–541 (2013) based on specimens collected in Georgia. Furthermore, notes on Cenopalpus lineola(Canestrini and Fanzago 1876) are included since it is frequently associated with C. wainsteini. Severe damage symptoms caused by this flat mite on its host plants were observed and are discussed herein.

The pin nematode, Paratylechus beltsvillensisn. sp. collected from rhizosphere soil of a Virginia pine tree (Pinus virginianaMill) growing in Little Paint Branch Park, Beltsville, Prince George’s County, Maryland, USA, is described and illustrated along with light and scanning electron photomicrographs. Females, males, and juveniles of this new species were recovered from soil samples using the sugar centrifugal flotation and Baermann funnel extraction methods. Morphologically, females are short, body length ranging from 245 to 267 μm, stylet from 70 to 75 μm long with anchor shaped knobs, vulva located at 70–73% and small vulval flap, spermatheca large, and ovoid filled with sperms. Lateral field with three incisures, of which the outer two are prominent. Tail slender, having a rounded tail terminus. Males without stylet and have a degenerated pharynx, spicules = 17–20 µm and gubernaculum = 5.0–5.5 µm. Both morphological observations and molecular analysis of ITS and partial 28S ribosomal RNA gene sequences indicated that the specimens collected from the soil at Beltsville Park from rhizosphere soil samples from Virginia pine represents a new pin nematode species.

A TDNA mutant, in the single copy Blistering1locus, was created in Penicillium expansum. The mutant showed reduced decay in apple fruit, undetectable levels of patulin, and blistered hyphae. Mass spectrometry of proteins in liquid medium and mycelia revealed that it failed to secrete degrative enzymes and ones involved in patulin synthesis. Quantitative mass spectrometry of mycelial proteins revealed altered cellular networks controlling protein processing. These data show that Blistering1affects internal and external protein processing involving vesicle-mediated transport.

Scanning electron and light microscopy were used to examine pollen of the currently recognized species (and forms) within the genus Citrullus(Cucurbitaceae). Materials examined included: C. lanatus(Thunb.) Matsum. & Nakai, the citron (C. amarusSchrad.), the egusi [C. mucosospermus(Fursa) Fursa], C. colocynthis(L.) Schrad., C. rehmiiDe Winter, C. ecirrhosusCogn., and the gemsbok cucumber [C. naudinianus(Sond.) Hook. f.]—also referred to in the literature as Acanthosicyos naudinianus(Sond.) C. Jeffrey. Pollen of all species were similar in shape differing slightly in their polar (P) and equatorial (E) axes and P/E. In general, all were characterized as prolate and tricolpate with a small polar area and reticulate ornamentation. Flow cytometry revealed C values for the taxa examined as ranging from 0.8 to 1.04 pg DNA per 2C nuclei. A mutant affecting pollen ornamentation was identified in PI 482261, a C. amaruscitron from Zimbabwe. Pollen ornamentation on PI 482261 was rugulate. An examination of 15 additional accessions from neighboring areas in Zimbabwe revealed a second rugulate type in PI 482312, while the remaining 14 C. amarusaccessions were reticulate. Successful hybridizations were made between C. colocynthis(PI 652554) and C. naudinianus(GRIF 14032), and between C. rehmii(PI 670011) and C. naudinianus(GRIF 14032). The F1hybrids of both crosses were extremely vigorous and exhibited some characteristics (i.e., branching and storage root formation) associated with the male parent. Other characteristics such as tendril length and shape, and leaf size and shape, were intermediate between the parents. To date, the interspecific F1hybrids have produced only shrunken (nonviable) pollen.

Radish (Raphanus sativusvar. longipinnatus)microgreens were produced from seeds inoculated with Escherichia coliO157:H7 by using peat moss-based soil-substitute and hydroponic production systems. E. colipopulations on the edible and inedible parts of harvested microgreen plants (7 days postseeding) and in growth medium were examined. E. coliO157:H7 was shown to survive and proliferate significantly during microgreen growth in both production systems, with a higher level in the hydroponic production system. At the initial seed inoculation level of 3.7 log CFU/g, E. coliO157:H7 populations on the edible part of microgreen plants reached 2.3 and 2.1 log CFU/g (overhead irrigation and bottom irrigation, respectively) for microgreens from the soil-substitute production system and reached 5.7 log CFU/g for those hydroponically grown. At a higher initial inoculation of 5.6 log CFU/g seeds, the corresponding E. coliO157:H7 populations on the edible parts of microgreens grown in these production systems were 3.4, 3.6, and 5.3 log CFU/g, respectively. Examination of the spatial distribution of bacterial cells on different parts of microgreen plants showed that contaminated seeds led to systematic contamination of whole plants, including both edible and inedible parts, and seed coats remained the focal point of E. coliO157:H7 survival and growth throughout the period of microgreen production.

Biofilm-forming bacteria resident to food processing facilities are a food safety concern due to the potential of biofilms to harbor foodborne bacterial pathogens. When cultured together, Ralstonia insidiosa,a strong biofilm former frequently isolated from produce processing environments, has been shown to promote the incorporation of Escherichia coliO157:H7 into dual- species biofilms. In this study, interactions between E. coliO157:H7 and R. insidiosawere examined under different incubating conditions. Under static culture conditions, the incorporation of E. coliO157:H7 into biofilms with R. insidiosawas not significantly affected by either low incubating temperature (10°C) or by limited nutrient availability. Greater enhancement of E. coliO157:H7 incorporation in dual-species biofilms was observed by using a continuous culture system with limited nutrient availability. Under the continuous culture conditions used in this study, E coliO157:H7 cells showed a strong tendency of colocalizing with R. insidiosaon a glass surface at the early stage of biofilm formation. As the biofilms matured, E coliO157:H7 cells were mostly found at the bottom layer of the dual-species biofilms, suggesting an effective protection by R. insidiosain the mature biofilms.

We have developed a two-step replica molding method for rapid fabrication of biomimetically patterned plant surfaces (BPS) using polydimethylsiloxane (PDMS-BPS) and agarose (AGAR-BPS). Beyond providing multiple identical specimens that faithfully reproduce leaf surface microstructure, this approach also offers unique chemical, physical, and biological features. PDMS-BPS provide good structural durability for SEM examination, have surface wettability comparable to plant surfaces for coating development, and allow for real-time monitoring of biosynthesis through incorporation into microfluidic devices. AGAR-BPS are compatible with bacterial growth, recovery, and quantification, and enable investigation of the effects of surface topography on spatially varying survival and inactivation of Escherichia colicells during biocide treatment. Further development and application of these biomimetically patterned surfaces to study (and possibly modify) other aspects of plant–bacteria interactions can provide insight into controlling pathogen contamination in a wide range of applications.

Similar to phytopathogens, human bacterial pathogens have been shown to colonize the plant phylloplane. In addition to environmental factors, such as temperature, UV, relative humidity, etc., the plant cultivar and, specifically, the leaf blade morphological characteristics may affect the persistence of enteropathogens on leafy greens. This study was conducted to evaluate the effect of cultivar-dependent leaf topography and the role of strain phenotypic characteristics on Escherichia coliO157:H7 persistence on organic spinach. Spinach cultivars Emilia, Lazio, Space, and Waitiki were experimentally inoculated with the foodborne E. coliO157:H7 isolate EDL933 and its isogenic mutants deficient in cellulose, curli, or both curli and cellulose production. Leaves of 6-week-old plants were inoculated with 6.5 log CFU per leaf in a biosafety level 2 growth chamber. At 0, 1, 7, and 14 days, E. coliO157:H7 populations were determined by plating on selective medium and verified by laser scanning confocal microscopy. Leaf morphology (blade roughness and stoma density) was evaluated by low-temperature and variable-pressure scanning electron microscopy. E. coliO157:H7 persistence on spinach was significantly affected by cultivar and strain phenotypic characteristics, specifically, the expression of curli. Leaf blade roughness and stoma density influenced the persistence of E. coliO157:H7 on spinach. Cultivar Waitiki, which had the greatest leaf roughness, supported significantly higher E. coliO157:H7 populations than the other cultivars. These two morphological characteristics of spinach cultivars should be taken into consideration in developing intervention strategies to enhance the microbial safety of leafy greens.

Three different injection molded bioplastic (BP) pots, BP 29, BP 32, and BP 45 pots, containing processed feather fibers, were evaluated. Growth and flowering of Liliumhybrid ‘Triumphator’ and Begonia‘Bonfire’ were evaluated in new and reused BP pots. Net photosynthesis was measured and macro- and micro-elements were analyzed in ‘Triumphator’ lily. Ultrastructure of epidermis cells of ‘Triumphator’ lily were analyzed using a low temperature-scanning electron microscope (LT-SEM). Surface changes, the weight, and macro- and micro-elements of the BP pots were also analyzed. When lilies were grown in BP 32 pots, root and shoot growth were inhibited, flowering was delayed and the net photosynthesis was negative, grana development, and starch granules were not observed as compared to those in BP 45 pots. Changes in the surface of BP 32 pots after forcing lilies (used once) showed a distinct space between feather fibers and other constituents which could be due to the chemical changes resulting from absorption of water. When BP pots were analyzed for pH and macro- and micro-elements, the pH and the concentration of ammonium nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, and iron were significantly higher in the new BP 32 than those of BP 29 and BP 45 pots. Based on the growth and development of lily and begonia and net photosynthesis and grana development of lily, and foliar analysis of begonia grown in three different BP pots, it is concluded that BP 45 is recommended to grow lily and begonia when proper levels of nutrition are maintained during culture. Poor root growth and development of ‘Triumphator’ lily grown in new BP 32 pots could be associated with leaching of toxic substances once the pots absorb water during the culture.

AbstractShiga-toxigenic Escherichia coliO157:H7 outbreaks have been linked to consumption of fresh produce. It is generally recognized that bacterial attachment to vegetal matrices constitutes the first step in contamination of fresh produce. Cellular appendages, such as curli fibers, and cellulose, a constituent of extracellular matrix, have been suggested to be involved in E. coliattachment and persistence in fresh produce. A comparative evaluation was conducted on the ability of Shiga toxin-producing E. coliO157:H7 strains EDL933 and 86-24, linked to two independent foodborne disease outbreaks in humans, and their mutants deficient in curli and/or cellulose expression to colonize and to firmly attach to spinach leaf. Inoculated spinach leaves were incubated at 22°C, and at 0, 24, and 48 h after incubation loosely and strongly attached E. coliO157:H7 populations were determined. Curli-expressing E. coliO157:H7 strains developed stronger association with leaf surface, whereas curli-deficient mutants attached to spinach at significantly (p<0.01) lower numbers. Attachment of cellulose-impaired mutants to spinach leaves was not significantly different from that of curliated strains. The relative attachment strength of E. coliO157:H7 to spinach increased with incubation time for the curli-expressing strains. Laser scanning confocal microscopy (LSCM) analysis of inoculated leaves revealed that curli-expressing E. coliO157:H7 were surrounded by extracellular structures strongly immunostained with anti-curli antibodies.Production of cellulose was not required to develop strong attachment to spinach leaf. These results indicate that curli fibers are essential for strong attachment of E. coliO157:H7 to spinach whereas cellulose is dispensable.

Abstract: This study was conducted to (a) characterize bio-plastic pellets containing feather fibers by low temperature-scanning electron microscopy (LT-SEM) and X-Ray diffraction analysis, (b) evaluate growth and flowering of Begonia boliviensis A. DC. ‘Bonfire’ when grown in a medium amended with pellets, and (c) analyze macro- and micro-elements in the medium and plant tissues of begonia. Based on physical and chemical analyses of six types of pellets mixed in the medium, pellets 32 (P 32), 37 (P 37), 40 (P 40), and P NaS (P NaS), P NaS containing sodium sulfite and > 30% glycerol were not suitable and not recommended for future evaluations. Pellets containing glycerol at 10% were not suitable for the use as an ingredient for commercial growing media and P 45 is considered suitable pellets to prepare pots.

Abstract: This study was conducted to evaluate the growth and flowering of Begonia boliviensis A. DC. ‘Bonfire’ when grown in the growing medium mixed with pellets from biobased plastic resins containing chicken feather fibers, and analyze macro- and micro-elements in soil and leaf tissues during different developmental stages of begonia. Growth, flowering, and foliar analysis of plants grown in 10 cm pots containing 95 grams medium mixed with 6 grams each of pellet 29 (P 29), 32 (P 32), 37 (P 37), or 40 (P 40), 3 grams of Na (P NaS), or 9 grams of 45 (P 45) were similar to the control plants. Extra nitrogen was available from P 32 and P 37 based on the growing medium and foliar analysis of plants grown in P 32 (P 32 plant) and P 37 plant during the first 59 days after planting (DAP). Slow growth, low flowering percentage, or even the death of B. boliviensis ‘Bonefire’ grown in P NaS medium is attributed to high pH and high sulfur concentration. Based on the pH, soluble salts level, and the concentrations of macro- and micro-elements in the medium and leaves, P 45 pellet is the suitable source, if nitrogen is supplied constantly to the optimum level. Pellets prepared following mixing > 30 feather fibers without using glycerol should be further tested.

Irrigation water and washing water have been inferred to be associated with contamination of fresh fruits and vegetables with pathogenic microorganisms infectious for humans. The objective of the present study was to determine whether apples experimentally contaminated with Cryptosporidiumoocysts represent a food safety concern. Laser scanning confocal microscopy revealed no morphological changes in Cryptosporidium parvumoocysts attached to apples after 6 weeks of cold storage, suggesting that oocysts might remain viable and possibly infectious during prolonged storage. Mice were fed apple peels from experimentally contaminated apples to determine whether oocysts had remained infectious on apples stored for 4 weeks. All mice developed cryptosporidiosis. To evaluate the strength of oocyst attachment to apples, washing methods that have been reported to be helpful for recovery of oocysts from various foodstuffs were evaluated, except that the intensity of washing was increased in the present study. None of the tested washing methods succeeded in completely removing oocysts from the apple peel. The most efficient removal (37.5%) was achieved by rigorous manual washing in water with a detergent and by agitation in an orbital shaker with Tris–sodium dodecyl sulfate buffer. Glycine and phosphate-buffered saline buffers had no effect on oocyst removal. Scanning electron microscopy revealed that some oocysts were attached in deep natural crevices in the apple exocarp and others were attached to the smooth surface of the peel. Some oocysts were closely associated with what appeared to be an amorphous substance with which they might have been attached to the apple surface.

Hybrids between Medicago sativasubsp. falcataand M. sativasubsp. sativacan result in high levels of heterosis for alfalfa forage production. However, commercially viable alfalfa cultivars also must have acceptable performance for other agronomic traits, including regrowth following harvest and appropriate autumn dormancy. In this study, we characterized an F1population derived from the cross of the two subspecies for the genetics of forage production, forage height, and forage regrowth at three harvests in two Iowa locations for 1 yr. Quantitative trait loci (QTLs) controlling these traits were mapped on a genetic linkage map developed from this population. Broad‐sense heritabilities and genetic correlations among the traits were high. Marker alleles associated with QTLs for these traits were contributed by each parental genome, suggesting that both subspecies of cultivated alfalfa may contribute to the improvement of these traits. Multiple regression models accounted for between 11 and 44% of the trait variation. The most marker–trait associations were detected during the first harvest. Marker effects were generally similar across harvests. Markers associated with autumn regrowth tended to be different from those associated with regrowth earlier in the season, suggestive of the identification of autumn dormancy effects. The winter hardiness gene MsaciBis a candidate locus for yield and regrowth, being associated with yield across three harvests and with autumn regrowth. A subset of alleles was associated with more than one of the traits. Major alleles for the three traits appear to reside primarily on linkage groups (LGs) 3, 4, 5, and 7.

Biomass production represents a fundamental biological process of both ecological and agricultural significance. The genetic basis of biomass production is unknown but asssumed to be complex. We developed a full sib, F1mapping population of autotetraploid Medicago sativa(alfalfa) derived from an intersubspecific cross that was known to produce heterosis for biomass production. We evaluated the population for biomass production over several years at three locations (Ames, IA, Nashua, IA, and Ithaca, NY) and concurrently developed a genetic linkage map using restriction fragment length polymorphism (RFLP) and simple sequence repeat (SSR) molecular markers. Transgressive segregants, many of which exhibited high levels of heterosis, were identified in each environment. Despite the complexities of mapping within autotetraploid populations, single‐marker analysis of variance identified 41 marker alleles, many on linkage groups 5 and 7, associated with biomass production in at least one of the sampling periods. Seven alleles were associated with biomass production in more than one of the sampling periods. Favorable alleles were contributed by both parents, one of which is from the M. sativasubsp. falcatagermplasm. Thus, increased biomass production alleles can be gleaned from unadapted germplasm. Further, the positive quantitative trait locus (QTL) alleles from the parents are partially complementary, suggesting these loci may play a role in biomass production heterosis.

A cytogenetic investigation was conducted on four historically putatively distinct nondormant alfalfa germplasm sources, African, Chilean, Peruvian, and Indian tetraploid alfalfa [Medicago sativassp. sativa(L.) L. & L.; 2n= 4x= 32]. C‐banding, image analysis, and cluster analysis was used to test the hypothesis that chromosome structure differed among the four nondormant alfalfa populations. Cytogenetic analyses revealed polymorphisms for heterochromatic DNA in the number and location of constitutive heterochromatic DNA both within and among genotypes. However, this variability did not prevent recognition of homologous chromosomes. Karyotypes of Peruvian and Indian populations were developed. The reference African population was used to compare the karyotypes of Peruvian and Indian populations as well as the previously published Chilean population. In general, the number of heterochromatic DNA bands was similar for the African, Chilean, and Peruvian populations; however, the Indian population had significantly fewer heterochromatic bands than the other three. Cluster analysis based on all eight chromosomes yielded no clear separation of the nondormant alfalfa populations possibly because of the lack of chromosomal rearrangements, similar genetic backgrounds of the initial introductions, intercrossing of the different sources, genetic drift during maintenance, and/or common genetic backgrounds of the original parental germplasm sources.

A cytogenetic investigation was conducted on the tetraploid alfalfa [Medicago sativasubsp. sativa(L.) L. & L.] Chilean germplasm source PI 536534 using the combined techniques of C‐banding and image analysis. Cluster and multiple correspondence analyses were utilized to compare the C‐banding patterns of the Chilean germplasm source and the previously published African germplasm source. Cytogenetic analyses revealed polymorphisms for heterochromatic DNA in the 19 plants observed in detail. Abundant variability in the number, intensity, and location of constitutive heterochromatic DNA was noted; however, this variability was not sufficient to preclude recognition of homologous chromosomes. Five out of the 50 plants studied were aneuploids (2n= 4x+ 1 = 33 or 2n= 4x− 1 = 31) because of the presence or absence of a chromosome with a satellite. The Chilean karyotype resembled the reference tetraploid African alfalfa karyotype; however, a reduction in the total amount of heterochromatic DNA was observed. Cluster analysis and multiple correspondence analysis based on all eight alfalfa genome chromosomes yielded no clear separation of Chilean and African germplasms. However, the analysis of C‐banding patterns of Homolog 1 of Chromosome 8 in Chilean and African germplasms was effective in separating the two germplasm sources with the exception of two individuals from each germplasm source which clustered together.

A reference karyotype of tetraploid alfalfa (Medicago sativasubsp. sativa, 2n=4x=32) African Population germplasm source (PI 536539) was constructed using the combined techniques of C‐banding and image analysis. The image analysis system is a method of obtaining enhanced images of chromosomes in which morphological data can be obtained for the development of karyotypes. In addition, C‐banding is a diagnostic tool for distinguishing the homologous chromosomes of alfalfa. Chromosome analysis of tetraploid alfalfa revealed that alfalfa has four similar series of chromosomes based on their chromosome morphology and C‐banding. The karyotype of African Population alfalfa germplasm consists of one set of chromosomes with satellites (SATs, Chromosome 8), four sets of submetacentric chromosomes (Chromosomes 1–4), and three sets of metacentric chromosomes (Chromosomes 5–7). All of the chromosomes have centromeric bands and a terminal band on the short arm, with the exception of the SAT. Interstitial bands were observed on the short arm of each of the chromosomes, with the exception of Chromosome 7. Chromosomes 1, 2, and 3 have interstitial bands on their long arms. There exists considerable variability in the number, intensity, and location of the constitutive heterochromatic DNA; however, this variability is not sufficient to preclude recognition of the homologous chromosomes. The chromosome banding pattern of the African Population germplasm resembles the distribution of heterochromatic DNA C‐bands of diploid M. sativasubsp. caerulea(Less. ex Ledeb.) Schmalh. The African Population karyotype of alfalfa developed in this study is suggested as the reference for the development of additional chromosome maps of diverse alfalfa populations.

Polyploidy in blackberries and ploidy differences between Rubus species are obstacles to the efficient introduction of valuable germplasm, both intra- and interspecific, into blackberry breeding programs. Expansion of the germplasm base would be facilitated by reducing the ploidy level of blackberry cultivars to the diploid level. In this report selection of twin seed, interspecific hybridization, and pollen irradiation were compared as methods in the recovery of dihaploids from tetraploid blackberry cultivars. One dihaploid was obtained through selection of twin seed and several were obtained following interspecific hybridization. The infrequency of twinning and difficulty in detecting twin seed in Rubus reduced the efficiency of this method. The efficiency with which dihaploids could be obtained following interspecific hybridization varied with the pollen parent. Reduced seed set and seed quality following pollinations with respectively R. parvifolius and R. hirsutus could be used to advantage in the recovery of dihaploids from blackberries. Ploidy reduction in several tetraploid blackberry cultivars was obtained following pollinations with 100 and 150 kR gamma irradiated pollen. Most of the seedlings obtained at the 50 kR dosage were aneuploid. Pollen irradiation at 150 kR was the most efficient method of obtaining dihaploids from tetraploid blackberries. Twenty percent of the seedlings obtained following this treatment were dihaploid.

The United States National Plant Germplasm System contains 3159 accessions from 36 species of annual Medicago. Although there is increasing interest in the annual medics for use in sustainable agriculture, the U.S. collection is under utilized because of lack of agronomic information. Development of a core collection could facilitate easier access to the germplasm collection and enhance its use. The core collection should consist of a sample of accessions that represents the range of variability within the germplasm collection with minimum redundancies. To select a core collection of annual Medicagospecies, a subset of 1240 accessions was evaluated during the summer of 1990 for 16 agronomic and morphological traits. Accessions within species were grouped by cluster analysis utilizing an unweighted pair group method with arithmetic averages. Intraspecific phenotypic diversity determined the number of accessions for that species selected for the core collection. One accession per cluster was selected for each species for the core collection. Accessions were chosen within a species to represent the greatest diversity in geographical regions. The selected core collection of 211 accessions was reevaluated during the summer of 1991. The core collection was found to represent the variability of the germplasm collection and to remain stable between the two evaluation years. This study can be used as a model method for selecting a core collection for multispecies germplasm collections.

Ostertagia ostertagiis an abomasal parasite with significant economic impact on the cattle industry. Early host immune responses are poorly understood.

The collophore of Entomobrya multifasciata (Tullberg) (Collembola: Entomobryidae) is composed of four segments. The third segment telescopes in and out of the second and the fourth is an eversible vesicle that is entirely enclosed in the third when not deployed. Low temperature scanning electron micrographs document that the collophore may remain adhered to the substrate even as the springtail initiates its jump. This adherence appears to force the posterior abdomen into the air, causing the jump itself to be initiated in a forward direction and accompanied by a forward flip. Among the several other documented functions of the collophore, we suggest that it may serve to affect the direction and trajectory of the springtail during its jump.

Calmodulin is a ubiquitous calcium sensor to recognize the different developmental and/or stimulus-triggered calcium changes and regulate plant growth and development. However, the function of calmodulin remains elusive for fleshy fruit development. We performed expression studies of a family of six calmodulin genes (SlCaMs) in tomato fruit. All calmodulins showed a double peak expression pattern. The first flat peak appeared at 10–30 days after anthesis, but their expression rapidly declined at mature green and breaker. Then a sharp and even higher peak came at turning/pink stages. Among six calmodulins, SlCaM1 had the highest expression during fruit enlargement, whereas SlCaM2 was the major calmodulin during fruit ripening. However, SlCaMs showed different patterns in three ripening mutants rin, Nor and Nr. In particular, at the stages corresponding to mature green and breaker, the expression levels of SlCaMs in those mutants were significantly higher than wild-type. Furthermore, SlCaMs, especially SlCaM2 were upregulated by ethylene. Transiently overexpressing SlCaM2 in mature green fruit delayed ripening, while reducing SlCaM2 expression accelerated ripening. Our results suggest that SlCaMs play double roles to regulate fruit ripening. Prior to the ethylene burst, the ethylene-independent repression of SlCaMs might be critical for fruit to initiate the ripening process. After the ethylene burst, SlCaMs could participate in the ethylene coordinated rapid ripening.

This paper reports the potential usefulness of low temperature-scanning electron microscopy (LT–SEM) to evaluate morphology and predation behavior of the six-spotted thrips (Scolothrips sexmaculatus Pergande) against the two-spotted spider mite [Tetranychus urticae (Koch)]. Morphological features of stage II larva, pupa, and adult six-spotted thrips are imaged for the first time, including fine detail of (1) chemoreceptors on larval and adult antennae and (2) structural differences of the mesothoracic spiracle (or the stigmata). Aspects of predation by the six-spotted thrips on the two-spotted spider mites are seen for the first time using LT–SEM. Based on these images, two possible functions of the barbed setae on the six-spotted thrips may be (1) its potential to eliminate sticky exudates on webbing laid down by the mite, and (2) barbs may redirect web strands away from the body of the thrips as it approaches its prey.