Control of Fruit Ripening in Peach, Prunus persica: Action of Succinic Acid-2,2-Dimethylhydrazide and (2-Chloroethyl)Phosphonic Acid

1974 ◽  
Vol 1 (1) ◽  
pp. 77 ◽  
Author(s):  
NE Looney ◽  
WB Mcglasson ◽  
BG Coombe

Fruits of Halehaven and Fragar peaches (mid- and late season respectively) were sampled and examined weekly during one complete growing season. The period of rapid growth following anthesis (stage I) was characterized by relatively high respiration and ethylene production rates. Fruits of both cultivars entered the subsequent period of slow growth (stage II) together. Ethylene production was low and respiration declined throughout stage II. Sprays of (2-chloroethyl)phosphonic acid (ethephon), but not succinic acid-2,2-dimethylhydrazide (SADH), resulted in increased ethylene evolution by stage II fruits. Neither chemical altered respiration or the duration of stage II. Both chemicals, however, advanced commercial harvest and promoted ripening of fruits sampled throughout the final rapid growth period (stage III). All fruits sampled during stage III showed a climacteric-like increase in respiration and ethylene production. The horticultural effectiveness of SADH and ethephon appears to be due to a promotion of physiological activity in stage III. Abscisic acid in peach pericarp increased just before and during stage III. Possible roles for abscisic acid and ethylene in regulating the stage II-stage III transition in peaches and other fruits are discussed.

1976 ◽  
Vol 3 (4) ◽  
pp. 429 ◽  
Author(s):  
PH Jerie ◽  
DJ Chalmers

Ethylene production by whole fruit and mesocarp pieces of peach [Prunus persica (L.) Batsch. cv. Golden Queen] was measured throughout the growing season. Peach fruit have a double-sigmoid growth curve, in which a lag period of slow weight increase (stage II) is followed by a rapid stage of weight increase (stage III). Changes in ethylene production could not be related to stage I- stage II transitions, and ethylene remained low at the start of fresh weight stage III. Two weeks later, ethylene production rose sharply at the same time as the fruit started accumulating dry weight in dry weight stage III. Mesocarp pieces produced ethylene in a pattern similar to that of whole fruit. We conclude that, in peach, increasing ethylene production is one of the hormonal changes involved in dry matter accumulation during stage III of fruit growth.


1976 ◽  
Vol 3 (6) ◽  
pp. 809 ◽  
Author(s):  
WB Mcglasson ◽  
I Adato

The concentrations of free and base-hydrolysable (bound) abscisic acid (ABA) were measured in fruits of cv. Rutgers (normal) and of the mutants Nr, rin and nor during growth, maturation and senescence. Measurements were made also of postharvest changes in free ABA in immature Rutgers fruits. Free ABA began to accumulate rapidly in the pericarp of developing fruits of Rutgers, Nr and rin during the period of most rapid growth but accumulation in nor was delayed and slower. Peak concentrations in Rutgers, Nr and rin were similar but the maximum level in nor was about 50% lower. Peak concentrations of free ABA coincided with the completion of growth in Rutgers and rin but peak levels in Nr and nor were not reached until several days later. Colouring in all strains occurred at approximately the same time as the accumulation of peak concentrations of free ABA. Changes in bound ABA paralleled those in free ABA in pericarp tissue of all strains but the levels were about one-seventh of those of free ABA. Free and bound ABA were measured in seeds and associated mucilaginous tissue only in 50% developed and fully grown fruits. In the younger fruits of Rutgers, Nr and rin, this fraction contained a higher concentration of free ABA than the pericarp tissue. In fully grown fruits, the level of ABA in the seeds and associated tissue was much less than in this fraction of younger fruits and less than half that in the pericarp tissue. Free ABA in seeds and associated tissues remained low in nor fruits of both ages. The ratios of bound and free ABA in seeds and associated tissues in all strains were generally similar to those found in pericarp tissue. In Rutgers fruits, free ABA increased after harvest. It is suggested that ABA is produced in both pericarp and seeds plus associated mucilaginous tissue. Accumulation of ABA does not seem to be a result of increased ethylene production but conversely may be involved in the increased ethylene evolution which accompanies ripening in normal strains. Since the pattern of changes in ABA and the accumulation of peak concentrations in pericarp tissue was not consistently related to growth but was closely related to the onset of symptoms of ripening or senescence, ABA may be a regulator of ripening in the tomato.


1975 ◽  
Vol 2 (4) ◽  
pp. 623 ◽  
Author(s):  
DJ Chalmers ◽  
BVD Ende

Both the fresh weight and dry weigh increase of peach fruit [Prunus persica (L.) Batsch. cv. Golden Queen] have a double-sigmoid pattern. However, the lag period of slow fresh weight increase (fresh- weight-stage II) began and finished 1 month earlier than the start and finish respectively of the lag period of dry weight increase (dry-weight-stage II). Similarly, after the fruit had matured the rate of fresh weight increase declined 1 week before the rate of dry weight increase declined. The stone increased in dry weight rapidly in fresh-weight-stage II and this was accompanied by a compensating decline in the rate of dry weight increase of the flesh. There was no rapid increase in the dry weight of the seed until the rate of dry weight increase of the stone declined at the beginning of dry-weight-stage II. Although the decrease in the growth rate of the stone was accompanied by a marked increase in soluble sugar in the flesh, there was no compensating increase in growth rate of the flesh. While the second rapid stage of fresh weight increase (fresh-weight-stage III) was not accompanied by other apparent physiological changes, the second rapid stage of dry weight increase began at the same time as ripening commenced. The rate of natural abscission and the rate at which chlorophyll was degraded, both of which are known to indicate the level of ethylene present in the tissue, were high in dry-weight-stage I and dry-weight-stage III and low in dry-weight-stage II. The rate of growth of the fruit and its parts during different stages, the growth of the seed, the rate of abscission and chlorophyll degradation and the level of the major metabolites present in the fruit were all intricately interrelated. We have discussed the physiological significance of these observations and the way in which they may relate to earlier studies of peach fruit growth.


1999 ◽  
Vol 9 (1) ◽  
pp. 65-67 ◽  
Author(s):  
Robert C. Ebel ◽  
Arnold Caylor ◽  
Jim Pitts ◽  
Bobby Boozer

Ethrel [(2-chloroethyl)phosphonic acid] was applied at 0, 100 or 200 ppm (mg·L-1) for 3 years to the early maturing `Empress' peach [Prunus persica (L.) Batsch] to determine if bloom delay by Ethrel reduces fruit weight at harvest. Trees were hand thinned at 0 or 3 weeks after full bloom to equalize cropload across Ethrel treatments and to determine if any reduction in fruit weight by Ethrel can be compensated by harvest with earlier thinning. Ethrel at 200 ppm (mg·L-1) delayed bloom by 3, 0, and 7 days in 1994, 1996 and 1997, respectively. Despite bloom delay, Ethrel did not delay harvest or reduce fruit weight. Thus, earlier hand thinning was not necessary. Ethrel did not affect blossom density and was not phytotoxic to vegetative or reproductive organs. These results indicate that even with the shorter fruit growth period of early maturing peach cultivars such as `Empress', there is sufficient time for fruit growth to recover on Ethrel treated trees so that fruit weight at harvest is not reduced.


1997 ◽  
Vol 122 (3) ◽  
pp. 415-421 ◽  
Author(s):  
Jordi Marsal ◽  
Joan Girona

Relationships between midday (Ψmd) and predawn (Ψpd) leaf water potential, stomatal conductance (gs), and net CO2 assimilation rate (A) were determined at different fruit growth stages and for 2 years with different fruit loads in a `Sudanell' peach [Prunus persica (L) Batsch] plot subjected to two regulated deficit irrigation (RDI) strategies plus a control irrigation treatment. A postharvest RDI (PRDI) treatment was irrigated at 0.35 of the control after harvest. The second treatment (SPRDI) applied RDI during Stage II, the lag phase of the fruit growth curve, at 0.5 of the control and postharvest at 0.35 of the control. The control treatment and the PRDI and SPRDI when not receiving RDI were irrigated at 100% of a modified Penman crop water use calculation (ETo) in 1994, a full crop year, and 80% in 1995, a year of nearly zero crop. In 1995, with 80% of the 1994 irrigation rate and no crop, the Ψmd was higher, probably because of the lower crop load, while Ψpd was lower, probably because less water was applied to the soil. The relationship of gs and A with Ψmd during Stage II was steeper than during postharvest. Low Ψmd was not indicative of a depression in gs and A in Stage III. Osmotic leaf water potential at turgor loss (Ψπ0) as derived from pressure-volume curves was more negative during Stage III and postharvest (about -2.9 MPa) than in Stage II (about -2.7 MPa). The Ψmd measurements together with Ψπ0 determinations seemed to be more useful to characterize peach tree water status than Ψpd under soil water deficits because of their better relationship to midday stomatal closure.


1972 ◽  
Vol 52 (1) ◽  
pp. 73-80 ◽  
Author(s):  
NORMAN E. LOONEY

Succinic acid 2,2-dimethylhydrazide (Alar) and 2-chloroethylphosphonic acid (Ethrel) were applied to peach (Prunus persica L. cult "Redhaven") trees 7 and 9 weeks after bloom, respectively. Fruits harvested weekly throughout the growing season were examined for respiratory behavior and ethylene production with and without the addition of ethylene gas. All fruits harvested during the first (stage 1) of the two periods of rapid fruit growth, as well as mature fruits (in late stage 3), displayed a climateric respiratory pattern and produced appreciable amounts of ethylene. Alar significantly increased the ethylene production associated with ripening. Ethrel increased ethylene production only in ripening fruits not given the postharvest ethylene treatment. Both Alar and Ethrel advanced and favored uniform fruit ripening, the combination of these materials appearing to be most effective.


2020 ◽  
Vol 15 ◽  
Author(s):  
Athira K ◽  
Vrinda C ◽  
Sunil Kumar P V ◽  
Gopakumar G

Background: Breast cancer is the most common cancer in women across the world, with high incidence and mortality rates. Being a heterogeneous disease, gene expression profiling based analysis plays a significant role in understanding breast cancer. Since expression patterns of patients belonging to the same stage of breast cancer vary considerably, an integrated stage-wise analysis involving multiple samples is expected to give more comprehensive results and understanding of breast cancer. Objective: The objective of this study is to detect functionally significant modules from gene co-expression network of cancerous tissues and to extract prognostic genes related to multiple stages of breast cancer. Methods: To achieve this, a multiplex framework is modelled to map the multiple stages of breast cancer, which is followed by a modularity optimization method to identify functional modules from it. These functional modules are found to enrich many Gene Ontology terms significantly that are associated with cancer. Result and Discussion: predictive biomarkers are identified based on differential expression analysis of multiple stages of breast cancer. Conclusion: Our analysis identified 13 stage-I specific genes, 12 stage-II specific genes, and 42 stage-III specific genes that are significantly regulated and could be promising targets of breast cancer therapy. That apart, we could identify 29, 18 and 26 lncRNAs specific to stage I, stage II and stage III respectively.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
P Milani ◽  
L Obici ◽  
R Mussinelli ◽  
M Basset ◽  
G Manfrinato ◽  
...  

Abstract Background Cardiac wild type transthyretin (ATTRwt) amyloidosis, formerly known as senile systemic amyloidosis, is an increasingly recognized, progressive, and fatal cardiomyopathy. Two biomarkers staging systems were proposed based on NT-proBNP (in both cases) and troponin or estimated glomerular filtration rate, that are able to predict survival in this population. The availability of novel effective treatments requires large studies to describe the natural history of the disease in different populations. Objective To describe the natural history of the disease in a large, prospective, national series. Methods Starting in 2007, we protocolized data collection in all the patients diagnosed at our center (n=400 up to 7/2019). Results The referrals to our center increased over time: 5 cases (1%) between 2007–2009, 33 (9%) in 2010–2012, 90 (22%) in 2013–2015 and 272 (68%) in 2016–2019. Median age was 76 years [interquartile range (IQR): 71–80 years] and 372 patients (93%) were males. One hundred and seventy-three (43%) had atrial fibrillation, 63 (15%) had a history of ischemic cardiomyopathy and 64 (15%) underwent pacemaker or ICD implantation. NYHA class was I in 58 subjects (16%), II in 225 (63%) and III in 74 (21%). Median NT-proBNP was 3064 ng/L (IQR: 1817–5579 ng/L), troponin I 0.096 ng/mL (IQR: 0.063–0.158 ng/mL), eGFR 62 mL/min (IQR: 50–78 mL/min). Median IVS was 17 mm (IQR: 15–19 mm), PW 16 mm (IQR: 14–18 mm) and EF 53% (IQR: 45–57%). One-hundred and forty-eight subjects (37%) had a concomitant monoclonal component in serum and/or urine and/or an abnormal free light chain ratio. In these patients, the diagnosis was confirmed by immunoelectron microscopy or mass spectrometry. In 252 (63%) the diagnosis was based on bone scintigraphy. DNA analysis for amyloidogenic mutations in transthyretin and apolipoprotein A-I genes was negative in all subjects. The median survival of the whole cohort was 59 months. The Mayo Clinic staging based on NT-proBNP (cutoff: 3000 ng/L) and troponin I (cutoff: 0.1 ng/mL) discriminated 3 different groups [stage I: 131 (35%), stage II: 123 (32%) and stage III: 127 (33%)] with different survival between stage I and II (median 86 vs. 81 months, P=0.04) and between stage II and III (median 81 vs. 62 months, P<0.001). The UK staging system (NT-proBNP 3000 ng/L and eGFR 45 mL/min), discriminated three groups [stage I: 170 (45%), stage II: 165 (43%) and stage III: 45 (12%)] with a significant difference in survival: between stage I and stage II (86 vs. 52 months, P<0.001) and between stage II and stage III (median survival 52 vs. 33 months, P=0.045). Conclusions This is one of the largest series of patients with cardiac ATTRwt reported so far. Referrals and diagnoses increased exponentially in recent years, One-third of patients has a concomitant monoclonal gammopathy and needed tissue typing. Both the current staging systems offered good discrimination of staging and were validated in our independent cohort. Funding Acknowledgement Type of funding source: None


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