SOLAR RADIATION AFFECTS ´STARK REDGOLD´ NECTARINE FRUIT GROWTH AND DEVELOPMENT

SummaryThe influences of the temperature during plant raising and the age of plants at transplanting on the time of hearting and head weight at maturity of the crisp lettuce variety Saladin R100 were determined in seven experiments between 1984 and 1986.Plants raised at ambient temperatures and transplanted before the end of May produced heads which were heavier and matured later than those from plants raised at higher temperatures under glass. The influence of transplant age on head weight was much smaller than that of raising conditions and there were inconsistent effects on the time of crop maturity. When the head weights at maturity of all treatments were considered there were highly significant positive correlations with total solar radiation in the periods 7 and 10 days before 50% hearting occurred. Further examination of this effect revealed that heads heavier than 800 g were strongly associated with mean daily solar radiation exceeding 15MJ/m2 in the periods 7 and 14 days before 50% hearting. This suggests that breeding for stability of head weight from crop to crop is likely to be aided by selection for consistency of head weight under a range of light levels in the prehearting phase.The coefficient of variation of the period from transplanting to maturity, measured in terms of various environmental characters, was lowest using effective day-degrees, which take account of different levels of solar radiation at the same mean temperature. This suggests that effective day-degrees may be the best indicator of the duration of crop growth and therefore of benefit in developing techniques to predict the time of crop maturity.

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English walnut fruit growth and development

Scientia Horticulturae ◽

10.1016/0304-4238(83)90182-6 ◽

1983 ◽

Vol 21 (1) ◽

pp. 19-28 ◽

Cited By ~ 13

Author(s):

Katherine Pinney ◽

Vito S. Polito

Keyword(s):

Growth And Development ◽

Fruit Growth ◽

English Walnut

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Characteristics of Pollen Grains of Different Date Pollinator Cultivars and Their Metaxenia Effect on Secondary Metabolites, Enzymes and Other Biochemical Compounds of ‘piarom’ Dates at Different Stages of Fruit Growth

10.21203/rs.3.rs-968530/v1 ◽

2021 ◽

Author(s):

Ali Reza Shahsavar ◽

Asma Shahhosseini

Keyword(s):

Secondary Metabolites ◽

Growth And Development ◽

Pollen Grains ◽

Fruit Growth ◽

Total Phenol ◽

Pectin Methyl Esterase ◽

Date Fruit ◽

Biochemical Compounds ◽

Date Fruits

Abstract In this study, the characteristics of pollens of eight date pollinating cultivars including ‘Shahani’, ‘Zahedi’, ‘Beraem’, ‘Faryab’, ‘Sheikhali’, ‘Fard’ and ‘Jarvis’ were compared and their metaxenia effects on secondary metabolites, enzymes and other biochemical compounds of ‘Piarom’ date fruit was investigated in four stages of fruit growth and development. The pollens of these eight pollinating cultivars were compared in terms of carbohydrate, protein starch, total phenol, flavonoids, pectin methyl esterase, and amylase enzymes. According to the results, , pollens of ‘Sheikhali’, ‘Fard’, ‘Zahedi’ and ‘Shahani’ cultivars had higher amounts of the above compounds than other cultivars. Regarding the effect of pollens on the composition of ‘Piarom’ date fruit, ‘Fard’ and ‘Sheikhali’ pollens produced the lowest amount of soluable tannin, which resulted in better quality of ‘Piarom’ date fruits. Pollens of ‘Sheikhali’ and ‘Fard’ cultivars produced the highest amounts of glucose and fructose in the fruit. In relation to sucrose, ‘Jarvis’ and ‘Shikhali’ were the best. Pollens of ‘Sheikhali’ and ‘Fard’ cultivars caused the lowest amount of chlorophyll in different stages of fruit growth, indicating better decomposition of fruit chlorophyll and, as a result, better fruit quality. Pollens of ‘Sheikhali’ and ‘Fard’ cultivars produced the highest amount of secondary metabolites such as total phenol, carotenoids and anthocyanin at different stages of ‘Piarom’ date fruit development. Pollens of ‘Fard’ and ‘Sheikhali’ cultivars produced the highest levels of polygalacturonase, cellulase and invertase enzymes at different stages of ‘Piarom’ date fruit growth. Regarding cellulase enzyme, ‘Zahedi’ cultivar produced more ‘cellulase’ in fruit than ‘Sheikhali’. In general, the pollens of ‘Fard’ and ‘Sheikhali, in comparison with other cultivars, improved the quantity and quality of ‘Piarom’ date fruit, due to their metaxenia properties.

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Temporal expression patterns of fruit-specific α- EXPANSINS during cell expansion in bell pepper (Capsicum annuum L.)

10.21203/rs.3.rs-18016/v2 ◽

2020 ◽

Author(s):

Andrés Mayorga-Gómez ◽

Savithri Nambeesan

Keyword(s):

Cell Wall ◽

Cell Expansion ◽

Growth And Development ◽

Expression Patterns ◽

Fruit Growth ◽

Bell Pepper ◽

Temporal Expression ◽

Cell Wall Loosening ◽

Pepper Fruit ◽

Wall Loosening

Abstract Background Expansins (EXP) facilitate non-enzymatic cell wall loosening during several phases of plant growth and development including fruit growth, internode expansion, pollen tube growth, leaf and root development, and during abiotic stress responses. In this study, the spatial and temporal expression patterns of C. annuum α- EXPANSINS (CaEXPA) genes were characterized. Additionally, fruit-specific CaEXPA expression was correlated with the rate of cell expansion during bell pepper fruit development. Results Spatial expression patterns revealed that CaEXPA13 was up-regulated in vegetative tissues and flowers, with the most abundant expression in mature leaves. Expression of CaEXPA4 was associated with stems and roots. CaEXPA3 was expressed abundantly in flower at anthesis suggesting a role for CaEXPA3 in flower development. Temporal expression analysis revealed that 9 out of the 21 genes were highly expressed during fruit development. Of these, expression of six genes, CaEXPA5, CaEXPA7, CaEXPA12, CaEXPA14 CaEXPA17 and CaEXPA19 were abundant 7 to 21 days after anthesis (DAA), whereas CaEXP6 was strongly expressed between 14 and 28 DAA. Further, this study revealed that fruit growth and cell expansion occur throughout bell pepper development until ripening, with highest rates of fruit growth and cell expansion occurring between 7 and 14 DAA. The expression of CaEXPA14 and CaEXPA19 positively correlated with the rate of cell expansion, suggesting their role in post-mitotic cell expansion-mediated growth of the bell pepper fruit. In this study, a ripening specific EXP transcript, CaEXPA9 was identified, suggesting its role in cell wall disassembly during ripening.Conclusion This is the first genome-wide study of CaEXPA expression during fruit growth and development. Identification of a fruit-specific EXPAs suggest their importance in facilitating cell expansion during growth and cell wall loosening during ripening in bell pepper. These EXPA genes could be important targets for future manipulation of fruit size and ripening characteristics.

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Behavioural Thermoregulation in the Freeze-Tolerant Arctic Caterpillar, Gynaephora Groenlandica

Journal of Experimental Biology ◽

10.1242/jeb.138.1.181 ◽

1988 ◽

Vol 138 (1) ◽

pp. 181-193 ◽

Cited By ~ 1

Author(s):

OLGA KUKAL ◽

BERND HEINRICH ◽

JOHN G. DUMAN

Keyword(s):

Solar Radiation ◽

Growth And Development ◽

High Arctic ◽

The Sun ◽

Metabolic Rates ◽

Behavioural Thermoregulation ◽

Body Temperatures ◽

Feeding Site ◽

Freeze Tolerant ◽

Gynaephora Groenlandica

Larvae of the high arctic caterpillar, Gynaephora groenlandica (Wöcke) (Lepidoptera: Lymantriidae) spent most (60 %) of their time orienting towards the sun (i.e. basking) and only 20% feeding, primarily near midday. Larvae usually basked after feeding, then either fed again or moved to a new feeding site. Basking larvae reached their highest body temperatures (Tb) of ≊30°C (≊20°C in excess of the ambient temperature) when surrounded by snow on a calm day in the midday sun. Setae significantly decreased larval cooling rates. Maximal metabolic rates were attained in basking larvae, but at body temperatures below 10°C oxygen uptake was greatly reduced. Our studies indicate that G. groenlandica larvae are behaviourally adapted to utilize available solar radiation for growth and development.

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