Rate Of Increase In Length Research Articles

Cantang Group (Epinephelus Fuscoguttatus >< Epinephelus Lanceolatus) Hatcheries At The Blitok Installation Of Breach Water Cultivation Fisheries Center (BPBAP) Situbondo, East Java

To achieve success in the maintenance of cantang grouper requires mastery of techniques in good hatchery of cantang grouper (Epinephelus fuscoguttatus >< Epinephelus lanceolatus) in order to produce optimal productivity both in terms of quantity and quality. The aims of this study were: 1) To find out the development and growth rates in cantang grouper hatcheries (Epinephelus fuscoguttatus – lanceolatus), 2) To determine the condition of water quality in cantang grouper hatcheries (Epinephelus fuscoguttaus – lanceolatus), and 3) To determine the feasibility of cantang grouper hatcheries (Epinephelus fuscoguttaus – lanceolatus). The data analyzed in this study include data on growth, water quality, and business analysis. The results of the analysis showed that: 1) In a day the average length increase reached 0.074 cm and the percentage rate of increase in length of cantang grouper larvae for 29 days from the age of D30 – D58 was 7.4%. At the beginning of measuring the length of cantang grouper larvae, the average length was 1.12 cm and at the end of the observation the average value was 3.28 cm. 2) From the results of water quality maintenance, the temperature ranged from 29 – 31°C, oxygen dissolved 4.37 – 4.87 mg/L., pH 7.4 – 7.9, and salinity 28 – 30 ppt, 3) In terms of financial or business feasibility the cantang grouper hatchery activity at the Blitok BPBAP Situbondo Installation can be said to be feasible to do and profitable with a net profit of Rp. 665,904,233/year with an R/C ratio of 3.7. Break Event Point (BEP) price of Rp. 111,539,155/year with production BEP reaching 37,179 heads. Payback Period (PP) for 1 year.

PENGARUH POPULASI TANAMAN DAN DOSIS BIOFERTILIZER EXTRAGEN TERHADAP PERTUMBUHAN DAN HASIL TANAMAN WORTEL (Daucus carota L.) DI DATARAN RENDAH

A research with an aim to determine the effect of plant population, rate of biofertilizer ExtraGEN and their interaction on the growth and yield of carrot (Daucus carota L.) plants on the lowland was conducted. The experiment was carried out in the University of Mataram experimental field located in Narmada, West Lombok, NTB at an altitude of 136 m above the sea level from May to July 2019. The research used a Completely Randomized Factorial Design, consisting of 2 factors, namely the plant population and rate of biofertilizer ExtraGEN. The plant population consisted of 3 level : 1 plant/polybag, 3 plants/ polybag and 5 plants/polybag. The rate of biofertilizer ExtraGEN consisted of 4 levels: without biofertilizer ExtraGEN (control), with 100 ml/polybag biofertilizer ExtraGEN, with 200 ml/polybag biofertilizer ExtraGEN, and with 400 ml/polybag biofertilizer ExtraGEN. The combinations resulted in 12 interactions which were repeated 5 times. The data obtained were analyzed using Analysis of Variance (ANOVA) at 5 % significant level and followed by an Honestly Significant Difference (HSD) at the same level. The results showed that plant population affected the rate of increase in the length of petioles, total fresh weight of the roots/polybag and total dry weight of roots/polybag, but did not affect other parameters. Higher the plant population, lowered the rate of increase in length of the petioles increased the total weight of fresh roots biomass/polybag and the weight of total dry biomass/ploybag. Biomass weight per plant was obtained 4,07 g population of 1 plant/polybag, 1,37 g population of 3 plants/polybag and 0,56 g population of 5 plants/polybag. The rates of biofertilizer ExtraGEN did not affect the growth and yield of carrot plants on the lowland.

Current extent, temporal trends, and rates of gully erosion in the Gumara watershed, Northwestern Ethiopia

Gully erosion is among the foremost challenges for the sustainability of the land resource and agricultural activities in sub-humid northwestern Ethiopia. Understanding the situation of the current extent and temporal variation of gully expansion can help to curb the problem. However, temporal gully erosion studies are very limited. In this paper, the current extent, temporal change trends, and rates of gully erosion in the Gumara watershed are studied. A total of 241 cross-sections representing 44 gullies were surveyed, and their temporal changes over the period 2001–2018 are analyzed. The analysis was performed using a time series high-resolution satellite imageries and field surveys. The study result shows that currently, the total gully length is 10.04 km, and gully density is 1.87 km km−2. The total soil loss was 273, 066 t since the first gully incision in 1985. Similarly, the estimated total surface area damage was 11.42 ha. Gully length, density, surface area damage, and soil loss had increased from 3.83 to 10.04 km, 0.71–1.87 km km−2, 3.31–11.42 ha, and 60.58 to 273.07 × 103 t, respectively over the period 2001–2018. The average short-term rate of change of gully length, surface area damage, and soil loss were 1.75 m ha−1 yr−1, 13.44 m2 ha−1 yr−1, and 30.5 t ha−1 yr−1, respectively from 2001 to 2005. The medium-term average rate of increase in length, surface area damage, and soil loss was 0.68 m ha−1 yr−1, 8.91 m2 ha−1 yr−1, and 23.34 t ha−1 yr−1, respectively, over the period 2001–2018. Gullies are young and actively expanding. The expansion trend has been increasing with a decreasing rate, but the rate is still very high. However, gully rehabilitation practices so far are very limited, although, little effort is made in eucalyptus tree plantations by smallholder farmers. Therefore, the existing soil and water conservation practices on plots need to be strengthened, and large-scale gully bank rehabilitation is recommended by participating in all stakeholders’.

Experimental evaluation of the effect of water velocity on the development of string-attached kelp seedlings (Laminariales) with implications for hatchery and nursery production

Kelp sea farming is performed using seedlings (early stage of sporophyte development) attached to string, known as seedling string, which are produced from an indoor culture under controlled environmental conditions. However, very little is known about the influence of water movement and the optimal growth level of early kelp sporophytes on string. Thus, the present study evaluated the development of string-attached kelp seedlings (Undaria pinnatifida) simultaneously exposed to simulated seawater velocities in an indoor tank. The experiment was conducted using string that had seedlings approximately 2mm in length, whose growth was measured after 28 and 56 days of culture. Seawater velocity level was found to significantly influence both the rates of increase in total biomass (dry weight) and in length of kelp seedlings on string. Seedling growth rates increased up to a water velocity range of 15.8–17.1cm s−1 beyond which it declined. This pattern is similar for the two time periods explored during the experiment, although both growth rates were significantly higher during the first 28 days of culture than after 56 days of culture. This difference is related to the increase in kelp seedling size throughout the experiment, and this increase could affect the requirements and/or optimal environmental conditions for their growth. In addition, comparatively, the rate of total biomass increase for seedlings was significantly higher than the rate of length increase for seedlings, indicating seawater velocity favours greater biomass productivity over length increase. Based on these results, suitable seawater velocities are recommended that would be the most productive for kelp seedling growth on strings in hatchery and nursery phases.

Variation in the shell form of the swan mussel, Anodonta cygnea (Linea, 1876) in response to water current

A biometric study was conducted on the populations of swan mussel, Anodonta cygnea , belonged to water bodies with different water current velocity (high current: HC; low current: LC). The shell length, width, height, weight and age of the collected mussels were measured. The two groups had different age-classes distributions. The HC mussels had larger mean and maximal values of the biometric parameters. A high and medium correlation coefficient (width-length, height-length, and weight-length) were found in the HC and LC mussels, respectively. The weight-length relationships showed negative allometric pattern (HC: weight=3.6121x 0.8561 ; LC: weight=3.1362x 0.8508 ). The 1-2 years old mussels had the highest rates of increase in length, width and height in both groups. Based on the results, water current velocity influences biometric features and population structure of A. cygnea .

Access DeniedSingle-track length measurements of step-etched fission tracks in Durango apatite: “Vorsprung durch Technik”

Fossil and induced confined fission-tracks in the Durango apatite do not etch to their full etchable lengths with the current protocols. Their mean lengths continue to increase at a diminished rate past the break in slope in a length vs. etch-time plot. The mean length of the fossil tracks increases from 14.5(1) to 16.2(1) μm and that of the induced tracks from 15.7(1) to 17.9(1) μm between 20 and 60 s etching (5.5 M HNO 3 ; 21 °C); both are projected to converge toward ~18 μm after ~180 s. This increase is due to track etching, not bulk etching. The irregular length increments of individual tracks reveal a discontinuous track structure in the investigated length intervals. The mean lengths of the fossil and induced tracks for the standard etch time (20 s) for the (5.5 M HNO 3 ; 21 °C) etch are thus not the result of a shortening of the latent fission tracks but instead of a lowering of the effective track-etch rate v T . The rate of length increase of individual fossil confined tracks correlates with their length: older tracks are shorter because they etch slower. Step etching thus makes it possible to some extent to distinguish between older and younger fossil fission tracks. Along-track v T measurements could reveal further useful paleo-temperature information. Because the etched length of a track at standard etch conditions is not its full etchable length, geometrical statistics based on continuous line segments of fixed length are less secure than hitherto held.

Ecology of Fucus vesiculosus (Phaeophyceae) at its southern distributional limit: growth and production of early developmental stages

Growth and survival of two populations of Fucus vesiculosus were studied at its southern limit of distribution on the eastern Atlantic coast. Experimentally denuded areas at an estuarine and a semi-exposed site in an upwelling area (NW Spain) were followed for 17 months. Three different cohorts were detected during the sampling period. Differences among the three cohorts in terms of growth, reproduction and survival were detected. These differences may be due to the different time of appearance of the different cohorts or the presence of the previously established individuals when the second and third cohorts were recruited. Although growth of the cohorts recruiting in autumn was faster than for the cohorts recruiting in spring and summer, individual growth was represented in all cases by a logistic function, as the fastest rates of increase in length occurred during the first 6 months of life, and maximum length was attained after the thallus reached 1 year in age. In the same way, production was maximum for the first cohort, recruiting in autumn, even when it had the lowest survival rate, because of the rapid growth of survivors during spring and summer. For both populations, reproduction was continuous through the year but it was maximal during spring and summer. Protection from waves might have been thought to favour higher production and standing stock biomass values at the estuarine site compared with the semi-exposed site, while turnover rates of biomass were higher at the latter. Contrary to expectations, most of the nutrients available for the studied populations were not related to upwelling. Despite the fast initial growth of new recruits, both populations appeared to be very sensitive to clearance.

Edad y crecimiento de la carpa mayor de la India <i>Labeo rohita</i> (Cypriniformes: Cyprinidae) de los ríos tropicales de la cuenca Ganga, India

Labeo rohita is a member of the Indian major carp species and originally an inhabitant of the Ganga river network in India. It is among the top ten aquaculture species of the world. Since there is a lack of information on the growth pattern of the wild populations of this species, this study aimed at evaluating the pattern of age and growth, to support the development of effective management plans. A total of 1082 samples of L. rohita were obtained from May 2009 to July 2012 in six drainages of the Ganga basin. Scales of the fish were used to determine the age and growth by analyzing the annual rings growth. Out of six populations, a maximum 8+ age classes were recorded from two rivers (Betwa and Sharda). The back-calculated lengths at 8+ age class ranged from 86.22 cm to 91.66 cm. However, for the rest of rivers up to 7+ age classes were recorded. Among growth parameters, specific rate of length increase (C(l)) and specific rate of weight increase (Cw) showed decreasing trend, and three distinct life stages of L. rohita were recorded based on growth constant data (C(lt)). Analysis of variance (ANOVA) of the back-calculated length data set of six populations indicated a significant difference (p < 0.05). All three populations showed significant variation in length attainment during 1+ and 3+ age groups, while two populations showed significant variation in length attainment during the 2+ and 7+ age classes. Additionally, analysis of age frequency at different length intervals indicated that with increase in age class, number of fish samples was reduced. Since the pattern of life history traits of L. rohita have not been attempted in the recent past; therefore, this study will guide fisheries biologists about the current stock structure of this fish across different spatial scale of the Ganga basin.

Gypsum attack: performance of silicic pozzolans and Portland cements as determined by ASTM C 452-68

An earlier study with metakaolin and 10 Portland cements (PC) suggested that the ASTM C 452-68 test could be used to characterise and differentiate 28-day blended cements prepared with metakaolin. ASTM C 452-68 testing was once again conducted on 67 cements: the above 10 PC and 57 blended cements (POZC) containing 20%, 30% or 40% silica fume or diatomites (D or N) (= Z pozzolan). ASTM C 452-68 specimens were made from all the cements and their daily rate of increase in length was determined. The results showed that in a gypsum and water environment, the pozzolanic reactions induced by the reactive silica, SiO2r−, present in Z pozzolans, prevailed over the sulfatic hydration of the pozzolans themselves, reaching completion within 28 days. The explanation is that the formation rate (Vf) of the calcium silicate hydrate gel and silanol groups from the SiO2r− present in the Z pozzolan finishes being greater than the Vf observed for the ettringite forming slowly (ett-lf) from the C3A of ordinary Portland cement, which declines to zero, even though sulfatic hydration continues. The positive 7 and/or 28-day results obtained with the Frattini test (EN 196-5) and the tests set out in standards EN 450, ASTM C 311-07, EN 13263-1 or ASTM 618-95a provided proof that the ASTM C 452-68 test can be validly used to characterise 28-day POZC prepared with any natural or artificial pozzolan, subject, however, to the establishment of suitable standard physical-chemical requirements and specifications.

Growth of the Antarctic octocoral Primnoella scotiae and predation by the anemone Dactylanthus antarcticus

Growth rates in Antarctic marine ectotherms have been demonstrated to be slowed by two to five times compared to shallow-water temperate species, with no previous reports for octocorals. Here growth rates were estimated in the single axis, non-branching Antarctic octocoral Primnoella scotiae using repeated in situ length measures covering both summer and winter periods, for tagged colonies from three sites at Signy Island over a two year period. Mean rates of length increase at the different sites ranged from 0.96mmyr−1 to 55.3mmyr−1. The fastest individual colony growth rate at any site ranged from 2.55mmyr−1 to 175.6mmyr−1. The mean of the fastest growth rates across all sites was 33.0mmyr−1±14.7 (s.e.). Growth was significantly different between sites, and also between seasons and years. The mean overall increase in diameter of the average sized colony in the study (222.5mm in axis length) was 0.053mm yr−1. This is the slowest reported growth rate of any octocoral to date, and is five times slower than growth in most cold water octocorals. During the study it was noted that colonies were being attacked and consumed by the anemone Dactylanthus antarcticus. At one of the sites studied, between 5% and 8% of colonies surveyed were attacked each month. Anemone dispersal was via whole body inflation and drifting to new prey colonies that were attached to using tentacle-like column protuberances.

Fibre Length in Relation to the Distance from vessels and contact with rays in Acacia Mangium

Fibre length, as a function of radial or tangential distance from a vessel was estimated from serial cross sections. This new method is easier and faster than earlier methods which rely on photographic prints of transverse images for the analysis. When necessary virtual tangential and radial sections were produced from 3D data to enable fibre length estimation. Fibre length up to the 5th and 2nd fibres away from a vessel in radial and tangential directions, respectively, were significantly shorter than fibres at greater distance from the vessels. Fibre length strongly correlated with radial vessel distance (r = 0.83) up to the 5th fibre and then leveled off. Vessel-adjacent fibres on the radial or tangential side of a vessel did not significantly differ in length. However, the rate of length increase differed significantly in the radial and tangential directions. Percentage of contact with rays varied independently of fibre length.

Computed tomography measurement of the auricle in Han population of north China

A large number of anthropometric studies of the human auricle have been conducted in various populations. However, data from Han Chinese population are currently not available. The morphology of the auricle is highly complex. Consequently, traditional direct measurement techniques are unable to provide sufficient detail and accuracy. The present study sought to provide anthropometrical data on the auricles of Han Chinese individuals using a three-dimensional (3D) computed tomography (CT) reconstruction technique. A total of 485 data sets were utilised for this study. This sample consisted of data from 241 females aged 18-75 years and 244 males aged 18-74 years. All participants were categorised by gender and further into three age groups. Twelve anthropometrical dimensions of normal auricles were measured with 3D CT. Auricular, tragal, lobular and conchal indices were calculated to further examine the auricles. Earlobes were classified into three basic groups according to the angle of the junction of the earlobe with the cheek. Few of the anthropometrical data showed significant bilateral differences in auricular dimensions. The height of the tragus, lobular length, lobular width, conchal width, protrusion at tragal level and inclination angle of auricles showed no significant differences between males and females. All the linear dimensions of auricles, except the height of the tragus, conchal length and width, increased with age for both males and females. Protrusion at the superaurale and tragal levels showed a decrease of between 4% and 9% for males and 4% and 10% for females across all age groups. This study is the first to report CT measurement of normal auricles in a northern Han Chinese population. We found that this method enabled the complexity of the ear to be measured easily and accurately. Increasing our knowledge of normal auricular dimensions will be beneficial for plastic surgeons.

Hindmilk and weight gain in preterm very low‐birthweight infants

Feeding of own mother's milk to preterm very low-birthweight infants often results in suboptimal weight gain in these infants for whom energy requirements are high but in whom volume tolerance is limited. Therefore the purpose of the present paper was to investigate the effect of selective hindmilk feeding on the growth of preterm very low-birthweight babies. Preterm very low-birthweight babies admitted into the Special Care Baby Unit of the Jos University Teaching Hospital, Nigeria between April 2000 and July 2001 were randomized to hindmilk and composite breast milk feeding for 2 weeks. End-points were weight, occipitofrontal head circumference and length. For small-for-gestational-age babies, the infants fed on hindmilk gained weight at a mean rate of 12.92 +/- 10.95 g/kg per day as compared with a mean rate of 5.01 +/- 17.37 g/kg per day for their controls on composite milk (P < 0.0001). For appropriate-for-gestational-age babies, the mean rate of weight gain for the hindmilk group was 12.99 +/- 10.75 g/kg per day while that for their controls on composite milk was 8.29 +/- 20.56 g/kg per day (P < 0.01). There were no significant differences in the rates of increase in length and occipitofrontal head circumference between the groups. The lipid content of the hindmilk was 1.6-fold that of composite milk. Preterm very low-birthweight babies fed hindmilk had a higher rate of weight gain compared to those fed composite milk. It is recommended that the hindmilk fraction of expressed breast milk be predominantly used for the feeding of preterm very low-birthweight babies while in hospital to help shorten their duration of hospital stay.

The effects of delaying the start of moult on the duration of moult, primary feather growth rates and feather mass in Common Starlings Sturnus vulgaris

In many species of birds there is a close relationship between the end of breeding and the start of moult. Late‐breeding birds therefore often start to moult late, but then moult more rapidly. This is an adaptive mechanism mediated by decreasing day lengths that allows late‐breeding birds to complete moult in time. This study asked how these birds complete moult of the primary feathers more rapidly, and the consequences of this on the mass of primary feathers. Common Starlings Sturnus vulgaris were induced to moult rapidly in one of two ways. In the first experiment, one group was exposed to artificially decreasing photoperiods from the start of moult, whereas the control group remained on a constant long photoperiod. The second experiment was a more realistic simulation. Two groups were allowed to moult in an outdoor aviary. One group started to moult at the normal time. In the other, the start of moult was delayed by 3 weeks with an implant of testosterone. The duration of moult was significantly reduced in both the group experiencing artificially decreasing photoperiods and the group in which the start of moult was delayed. The faster moult rate was achieved by moulting more feathers concurrently. The rate of increase in length of each of the primary feathers, and their final length, did not differ between groups. The rate at which total new primary feather mass was accumulated was greater in more rapidly moulting birds, but this was insufficient to compensate for the greater numbers of feathers being grown concurrently. Consequently, the rate of increase in mass of individual feathers, and the final feather mass, were less in the rapidly moulting birds. A 3‐week delay in the start of moult is not an unrealistic scenario. That this caused a measurable decrease in feather mass suggests that late‐breeding birds are indeed likely to suffer a real decrease in the quality of plumage grown during the subsequent moult.

A detailed analysis of primary feather moult in the Common Starling Sturnus vulgaris– new feather mass increases at a constant rate

During moult, the rate that protein can be synthesized and used to grow new feathers must be a critical factor influencing the quality of new plumage. However, the rate that new feather mass accrues during moult has not been assessed in detail. To estimate this, the increase in length of each of the nine primary feathers (P1–P9) in 16 captive Common Starlings Sturnus vulgaris was measured at weekly intervals throughout moult. The rate of increase in length was similar for all primary feathers except P9, which increased more slowly. After completion of moult, these feathers were plucked, accurately measured and weighed. The distribution of mass along the length of each primary was assessed. Using these data, I estimated the rate that mass had increased for each feather during moult. For each individual primary, mass increased at a steady rate until almost fully grown. The rate of increase in mass was least for P1 and greatest for P9. The number of feathers growing concurrently decreased as moult progressed. The net result was that total new primary feather mass increased at a steady rate throughout most of moult (linear regression between start of growth of P2 and end of growth of P8; r2 = 0.991). Retrospective conversion of feather lengths into moult score showed that the increase in score was not linear. It was greatest early in moult and decreased as moult progressed. A scoring system that factors in distribution of mass within and between feathers may provide a more physiologically relevant measure of the progress of moult.

Morphometric analysis of fibre cell growth in the developing chicken lens

The optical characteristics of any lens are determined by its internal composition, size and shape. In the lens of the eye, the macroscopic form of the tissue reflects the arrangement and behaviour of its component cells. In the current study, we quantified changes in the morphology and organization of chicken lens fibre cells during embryonic development. Lens radii, fibre cell length, shape, cross-sectional aspect ratio, cross-sectional area, cross-sectional perimeter, and cell packing organization were measured from confocal and transmission electron micrographs using computer assisted image analysis. Derived values for cell surface area and volume were also calculated. Because of the radial symmetry of the avian lens, we were able to employ a novel coordinate system to track the fate of identified cohorts of cells at successive developmental stages. This allowed kinetic information, such as the rate of increase in length or volume, to be derived. By sampling identified cell populations (i.e. those located at a specific point on the lens radius) at regular intervals it was possible, for the first time, to reconstruct the life history of fibre cells buried within the cellular conglomerate of the lens. The measurements indicated that a surprising degree of structural remodeling occurs during fibre cell elongation and continues after extant cells have been buried by waves of newly differentiated fibres. Even in the anucleated cells of the lens core, the size and surface topology of the cells were altered continually during development. However, some aspects of fibre cell organization were established early in development and did not vary thereafter. For example, the packing arrangement of cells in the adult lens was traced to a cellular template established on the tenth day of embryonic development.

Effect of Salinity on Embryonic Development, Hatchability, and Growth of African Catfish, Clarias gariepinus, Eggs and Larvae

Effects of salinity on embryonic development and growth of African catfish, Clarias gariepinus, eggs and larvae were studied. Eggs were incubated at 27-29°C in 2,4,6,8, and 10 ppt sodium chloride. Rate of embryonic development was delayed in all salt solutions by 15, 15,28 and 30 minutes, in 2,4,6, and 8 ppt sodium chloride, respectively, when compared with the control group (0% salt); total mortality occurred at 12 hours after gastrula stage in the 10 ppt concentration. Percentage hatching was 45.1,47.7, 59.5,49.2, and 26.6% while percentage deformity was 10.4, 16.1, 52.0, 28.6, and 71.6% in 0, 2, 4, 6, 8, and 10 ppt salt treatments, respectively. There were significant differences (P <0.05) in the hatching percentage and in deformity percentage between 4, 6, and 8 ppt. Rate of yolk absorption was significantly faster in the control and 2 ppt salt treatments, but slower in 4, 6, and 8 ppt. Rate of increase in length was slower with increasing salinity. The optimum salinity for African catfish eggs and was between 0-2 ppt and acceptable up to 6 ppt. The results suggest that increasing salinity delayed hatching and development of African catfish eggs and larvae, respectively, as well as increased the deformity of the larvae.

Seasonal dynamics of biomass increase and shoot elongation in five co-occurring boreal forest bryophytes

The seasonal patterns of length and biomass increase in five co-occurring bryophytes (Dicranum majus, Hylocomium splendens, Plagiochila asplenioides, Ptilium crista-castrensis and Rhytidiadelphus loreus), were studied throughout one growing season in a boreal spruce forest by growing shoots in experimental assemblages at two densities at consecutive four-week intervals. Seasonal trends in the mean relative growth rate (RGR) were found, with highest RGR in spring and early summer (0.0025-0.005 gg-1 day-1) and a low or negative RGR in autumn. This temporal variation could best be explained by the variation in precipitation, but interactions with other environmental factors were important, especially in spring and autumn. The five species responded differently to the environmental conditions, with the result that their relative rank in RGR changed from period to period. However, the effect of density on RGR varied between periods, indicating that the impact of macroenvironmental conditions depends on shoot density. Mean rate of length increase (LGR) peaked in early summer (0.12-0.20 mm day-1) with low length increases in spring and late in the season. LGR varied among species, showing differences in both maximum length growth rate and temporal patterns of growth. Length increase did not follow the temporal patterns of biomass increase, and an evident uncoupling of biomass and length increase was found in all species. The cumulative seasonal increase in length and biomass varied among species with a twofold and ninefold variation among species in cumulative length and biomass increase respectively. Further, an effect of shoot density on cumulative biomass increase was found, with the higher biomass increase at the lower shoot density.

Snowdrop lectin inhibits development and decreases fecundity of the Glasshouse Potato Aphid ( Aulacorthum solani) when administered in vitro and via transgenic plants both in laboratory and glasshouse trials

The effects of snowdrop lectin ( Galanthus nivalis agglutinin, GNA) on the Glasshouse Potato Aphid ( Aulacothum solani) were tested by bioassays where the protein was incorporated into an artificial diet at a single concentration of 0.1% ( w v ). The results showed that the presence of GNA in the diet throughout the insect's life cycle decreased the fecundity of adult aphids, as measured by nymph production, by up to 65%, but normally caused only a marginal decrease (≤ 10%) in aphid survival. The deleterious effect of GNA was significantly reduced if insects were reared on control diet, and transferred to diet containing GNA at maturity. GNA was also shown to affect the development of nymphal aphids by measuring growth using image analysis software. The presence of GNA in the diet decreased the rate of increase in length and width of the aphids by up to 40%, and, in this assay, also caused high levels of mortality. GNA was expressed in potato plants, ( Solanum tuberosum L.) cv. Desirée, after transformation with a construct containing a gene encoding the protein driven by the CaMV 35S promoter. GNA expression levels in transgenic potato leaves were found to be in the range 0.3–0.4% of total soluble protein, as measured by immunodot blot analysis using polyclonal antibodies raised against the protein. Bioassays carried out under controlled environmental conditions, using clip cages, showed that the number of nymphs produced on these transgenic plants was significantly ( P < 0.01) reduced compared to that on non-transgenic control plants. The decrease in fecundity observed in this bioassay was similar to that seen in the artificial diet bioassays. Large scale glasshouse trials showed that the rate of population build-up on the GNA-expressing plants was approximately four-fold lower than on the control plants. These experiments demonstrate that the insecticidal effects of GNA observed in artificial diets can be reproduced in planta, both under laboratory bioassay conditions and in the glasshouse.

Relationship between the translocation of paratropomyosin and the restoration of rigor-shortened sarcomeres during post-mortem ageing of meat—A molecular mechanism of meat tenderization

The weakening effect of paratropomyosin on rigor linkages formed between actin and myosin was determined by measuring the restoration of rigor-shortened sarcomeres of chicken, pork and beef. We observed the rate of the post-mortem translocation of paratropomyosin from the A-I junction region of sarcomeres onto the thin filaments in the A-band, where rigor linkages had been formed; this agreed well with the rate of increase in length of rigor-shortened sarcomeres. The sarcomere lengths were found to be maximum at 1, 7 and 10 days post-mortem in chicken, pork and beef, respectively. Thus, translocated paratropomyosin weakens rigor linkages and brings about the recovery in the length of rigor-shortened sarcomeres. Paratropomyosin stimulates the resolution of rigor mortis, and is a key factor in meat tenderization during post-rigor ageing. These results powerfully support the ‘Calcium theory of meat tenderization’ which we have proposed.