Influence of some atmospheric factors affecting yield and single fruit weight in strawberry

The study of vertical displacements of hydrotechnical objects, slender constructions, opencast mines or flotation waste reservoirs often requires continuous geodetic monitoring, which in real time defines potential threats resulting from changes in the geometry of the object. In order to ensure high accuracy in determining vertical displacements, a precise robotic tacheometer is used as one of the monitoring sensors. In the case of trigonometric leveling, the quality of measurements is affected not only by the accuracy of the instrument, but also by the centre through which the laser beam emitted by it passes. The radius emitted by the tacheometer due to the layered structure of the atmosphere is deflected, and the angle that it creates with the theoretical course of rays is called the angle of vertical refraction. In order to eliminate the influence of this type of errors, so-called atmospheric correction is introduced to all tacheometric measurements. Currently, total stations automatically determine and introduce corrections for observation, usually using only air temperature and atmospheric pressure. However, the number of factors responsible for the change in atmosphere density, and thus the deflection of the laser beam is much greater. And its influence is also affected by the length of the target and roughness of the area over which the measurement is made. The paper presents the analysis of the significance of various atmospheric and terrain factors that may affect the value of the vertical refraction angle. By the multiple regression method, with the use of the analyzed factors, equations describing the phenomenon of vertical refraction for four seasons have been designated. The defined equation coefficients were used to determine the refraction angle for the observations recorded on the post-flotation waste tank. To confirm the rightness of introducing an additional atmospheric correction, analyses were performed showing the percentage of corrected results.

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SOME FACTORS AFFECTING UPTAKE OF CALCIUM BY APPLES DIPPED AFTER HARVEST IN CALCIUM CHLORIDE SOLUTION

Canadian Journal of Plant Science ◽

10.4141/cjps78-008 ◽

1978 ◽

Vol 58 (1) ◽

pp. 35-40 ◽

Cited By ~ 6

Author(s):

P. D. LIDSTER ◽

S. W. PORRITT

Keyword(s):

Calcium Chloride ◽

Chloride Solution ◽

Inverse Relationship ◽

Fruit Weight ◽

Calcium Chloride Solution ◽

Malus Pumila ◽

Factors Affecting ◽

The Core ◽

Golden Delicious ◽

Malus Pumila Mill

An inverse relationship occurred between fruit weight and increase in calcium (Ca) content in Spartan apples (Malus pumila Mill.) resulting from postharvest CaCl2 dips. The influence of fruit weight on Ca increase was greatest in tissue near the core. The addition of a thickener to the dip solution resulted in significantly higher flesh Ca levels. Ca absorption was significantly enhanced by treating with dip solutions which were colder than the fruit. Spartan apples absorbed less Ca from a postharvest CaCl2 dip than did McIntosh which absorbed less than Golden Delicious or Delicious. The use of a surfactant in the CaCl2 dipping solution did not affect Ca penetration into McIntosh or Delicious apples but decreased penetration of Ca into Spartan and Golden Delicious.

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Atmospheric Factors Affecting the Corrosion of Engineering Metals

10.1520/stp646-eb ◽

1978 ◽

Cited By ~ 3

Keyword(s):

Factors Affecting ◽

Atmospheric Factors

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Commercial bumble bee (Bombus impatiens) hives under exclusion netting systems for apple pollination in orchards

Renewable Agriculture and Food Systems ◽

10.1017/s1742170520000095 ◽

2020 ◽

pp. 1-11

Author(s):

Mélanie Normandeau Bonneau ◽

Olivier Samson-Robert ◽

Valérie Fournier ◽

Gérald Chouinard

Keyword(s):

Fruit Quality ◽

Quality Parameters ◽

Apple Fruit ◽

Negative Control ◽

Fruit Weight ◽

Bumble Bees ◽

Bombus Impatiens ◽

Bumble Bee ◽

Wild Bees ◽

Factors Affecting

Abstract Exclusion netting systems are effective in various contexts and are increasingly used to control crop pests. However, factors affecting pollination management under nets are poorly known. The pollination effectiveness of commercial bumble bee hives of Bombus impatiens Cresson (Hymenoptera: Apidae) was studied for apple production under exclusion netting systems in a research orchard located in Quebec, Canada during 2016–2017. Sixteen single-row plots of apple trees (plot length: 18.5 m, cultivar GingerGold) were subjected to one of the following four treatments during bloom: (1) introduction of a bumble bee hive placed at the end of the row, under nets; (2) introduction of a bumble bee hive placed in the middle of the row, under nets; (3) negative control with no pollinators, under nets and (4) agronomic control with nearby bee hives (<50 m), without nets. Resulting post-harvest fruit quality (e.g., fruit weight, size, number and distribution of seeds) was evaluated, as well as correlations between bumble bee visitation rates and fruit quality parameters were evaluated. Results suggest that bumble bees provided adequate pollination under exclusion netting systems and that resulting fruit quality was equivalent to that of apple fruit conventionally pollinated by honey bees and wild bees community (bumble bees and other bees) in the orchard environment. Positioning bumble bee hives in the middle of the row provided better fruit load homogeneity in pollinated trees. Additional discussion on bumble bees as apple pollinators and on pollen distribution methods is also included.

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Spatiotemporal Variation in Pollination Deficits in an Insect-Pollinated Dioecious Crop

Plants ◽

10.3390/plants10071273 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1273

Author(s):

Helena Castro ◽

Catarina Siopa ◽

Vinícius Casais ◽

Mariana Castro ◽

João Loureiro ◽

...

Keyword(s):

Management Practices ◽

Pollen Limitation ◽

Fruit Weight ◽

Pollination Services ◽

Opposite Pattern ◽

Factors Affecting ◽

Market Values ◽

Pollinator Abundance ◽

Production Values ◽

Set Up

Inadequate quantity and quality of pollen reaching the stigmas decreases the sexual reproductive output of plants, compromising yield. Still, the current extent of pollen limitation affecting yield (i.e., pollination deficits) is poorly quantified. This study is aimed at quantifying pollination deficits in kiwifruit orchards, a dioecious plant with a fruit caliber and market value largely dependent on pollination services. For that, we set up a pollination experiment and quantified services and yield provided by current pollination vectors, and under optimal pollination, over two years in a total of twenty-three orchards covering the kiwifruit production range in Portugal. We characterized nine fruit traits and used: (1) fruit weight to calculate pollination deficits and relate them with pollinator diversity and abundance, and environmental variables; and (2) production values, fruit caliber, and market values to calculate economic impact of pollination deficits. Results showed that pollination deficits were variable in time and space and were significantly and negatively correlated with pollinator abundance, while the opposite pattern was obtained for production, supporting the notion that a higher pollinator’s abundance is related to lower pollination deficits and higher yields. Understanding the factors affecting pollination deficits is crucial to depict the need for nature-based solutions promoting pollinators and to resort to management practices assisting pollination.

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