scholarly journals Fruit Diameter and Daily Fruit Growth Rate of Three Apple Cultivars on Rootstock–Scion Combinations

HortScience ◽  
1994 ◽  
Vol 29 (2) ◽  
pp. 79-81 ◽  
Author(s):  
Ismail A. Hussein ◽  
Donald C. Slack
Keyword(s):  
Growth Rate ◽  
Growth Period ◽  
Fruit Growth ◽  
Arid Climate ◽  
Cultivar Differences ◽  
Growing Seasons ◽  
Apple Cultivars ◽  
Fruit Diameter

The effect of three vigor-control apple (Malus domestics Borkh.) rootstock (seedling, MM.106, and M.7a) on fruit diameter of three cultivars ('Red Delicious', `Granny Smith', and `Gala') was studied over two growing seasons (1990-91) in the arid climate of Willcox, Ariz. Daily fruit growth rate (DFGR) and effective fruit growth period (EFGP) data indicate cultivar differences in DFGR as well as EFGP. Cultivars with a high DFGR had a relatively shorter EFGP. Rootstock had no significant effect on EFGP. Cultivar x rootstock interaction on fruit diameter was significant for DFGR, but not for EFGP. `Red Delicious' and `Granny Smith' trees produced larger fruits on MM.106 and M.7a than on seedling rootstock. For `Gala', there was no significant effect of all rootstock on fruit diameter.

scholarly journals Development and Testing of a Model to Rapidly Predict Apple Thinner Response

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 793C-793 ◽  
Author(s):  
D.W. Greene* ◽  
A.N. Lakso ◽  
T.L. Robinson
Keyword(s):  
New York ◽  
Growth Rate ◽  
Fruit Set ◽  
Accurate Method ◽  
Fruit Growth ◽  
Cold Weather ◽  
Accurate Predictor ◽  
Accuracy Of Prediction ◽  
June Drop ◽  
Fruit Diameter

Several thinning experiments were initiated in 2003 to test the hypothesis that monitoring fruit growth is an appropriate and accurate method to predict final fruit set early enough to apply supplemental thinners if appropriate. A total of eight thinning treatments were applied in Massachusetts and New York. On the day of thinner application 70 to 100 spurs were tagged on 4-8 trees (replications). All fruit within a spur were individually identified and fruit were measured. At 2 to 3 day intervals fruit diameter was measured at a designated point on the fruit. Growth rate of the fastest growing 20 fruit on the untreated trees was used as the criteria to determine growth rate of fruit that would persist to harvest. A fruit on a treated tree was predicted to abscise if growth rate slowed to 50% or less of the growth rate of the 20 fastest growing fruit on untreated trees. Cold weather in 2003 following thinner application slowed the response time to thinners. Thinning treatments were applied to Delicious, Golden Delicious, McIntosh, and Gala at 7-9-mm stage. BA, carbaryl, and combinations of NAA and carbaryl were used. In Massachusetts accuracy of prediction of final fruit set at 7-11 days after application ranged from 87% to 100% with and average of 95% accuracy compared to final observed drop at the end of June drop in July. In Geneva, N.Y., the temperature was so unseasonably cold following application that prediction of final set at 7 to 11 days after application was between 68% and 79% with an average of 74% accuracy. We conclude that prediction of final fruit set following growth rate of individual fruit shows promise as an accurate predictor of final fruit set early enough to apply supplemental thinners if appropriate.

scholarly journals REGULATION OF APPLE FRUIT GROWTH RATE BY TURGOR PRESSURE?

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 625e-625 ◽  
Author(s):  
Douglas D. Archbold
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Osmotic Potential ◽  
Turgor Pressure ◽  
Apple Fruit ◽  
Fruit Growth ◽  
Cultivar Differences ◽  
Soluble Carbohydrates ◽  
Soluble Carbohydrate ◽  
Carbohydrate Levels

Maintenance of positive cell turgor is an essential factor in cell, and fruit, expansion. Since apple fruit partition carbohydrates between the starch and soluble pools to maintain turgor, variation among cultivars in this osmoregulatory aspect may play an important role in defining cultivar-specific fruit growth rates. Cultivar-specific apple fruit growth rates were determined over a 6 week period following June drop during 2 seasons. Fruit water relations parameters and carbohydrate levels were also measured. Although cultivar differences were evident, generally, fruit absolute growth rate increased, relative growth rate (RGR) declined, water potential and osmotic potential declined, and turgor potential increased as the season progressed. Soluble carbohydrate levels increased over 6 weeks, while starch levels fluctuated. Soluble carbohydrates contributed 50 to 90% of the osmotic potential. RGR was not correlated to either turgor potential or the relative allocation of carbohydrates between the soluble and starch pools. Thus, although positive turgor was maintained, factors other than turgor per se determine fruit growth rate.

scholarly journals Pomegranate Fruit Growth and Skin Characteristics in Hot and Dry Climate

2021 ◽  
Vol 12 ◽  
Author(s):  
Mukul Joshi ◽  
Ze’ev Schmilovitch ◽  
Idit Ginzberg
Keyword(s):  
Growth Rate ◽  
Elastic Modulus ◽  
Growth Parameters ◽  
High Growth ◽  
Growth Period ◽  
Fruit Growth ◽  
Temperate Climate ◽  
Rapid Phase ◽  
Immature Fruit ◽  
Pomegranate Fruit

Pomegranate (Punica granatum L.) fruit is well known for its health-beneficial metabolites. The pomegranate peel consists of an inner thick spongy white tissue, and an outer smooth skin layer that accumulates anthocyanins in red cultivars when ripe. The skin is made up of epidermis cells covered by a cuticle, the latter being the first target of cracking and russeting. The present study focuses on the effect of Israel’s hot and dry climate on pomegranate growth, to elucidate the derived effects on fruit skin characteristics and its putative resistance to the building pressure from fruit expansion. Experiments were conducted for four years, in four orchards located in different regions of the country, each with a different typical microclimate. Fruit-growth parameters were followed using remote-sensing tools, microscopic study, and mineral analysis of the skin, followed by determination of the peel’s elastic modulus. Fruit expanded in two phases: a short rapid phase followed by a gradual phase with a sigmoidal growth-rate pattern. Extreme hot and dry climate during the period of maximal growth rate was associated with restricted growth and a high proportion of small-size fruit. Anatomical study indicated that the skin of mature pomegranate fruit is made up of epidermal cells that are relatively flat and spaced apart, and is expected to be less durable against internal pressure. In contrast, skin of early immature fruit has two layers of dense and rounded epidermis, and is expected to be more resistant to cracking. Tensile strength studies confirmed this trend—skin of mature fruit had a lower elastic modulus than young fruit. However, restrained growth due to extreme environmental cues may result in better resistance of the mature pomegranate fruit to cracking, and in better skin quality and appearance, albeit small fruits. On the other hand, temperate climate at the beginning of the growth period, which allows high growth rate and high daily shrinkage, leads to pomegranate skin disorders.

scholarly journals Development of a Fruitlet Growth Model to Predict Thinner Response on Apples

HortScience ◽  
2013 ◽  
Vol 48 (5) ◽  
pp. 584-587 ◽  
Author(s):  
Duane W. Greene ◽  
Alan N. Lakso ◽  
Terence L. Robinson ◽  
Phillip Schwallier
Keyword(s):  
Growth Rate ◽  
Fruit Set ◽  
Growth Period ◽  
Fruit Growth ◽  
Series Of Experiments ◽  
Individual Trees ◽  
Viable Method ◽  
Final Effect ◽  
June Drop ◽  
Measurement Period

Previous reports have provided evidence that measuring fruit growth rate may be a viable method to predict if a fruit will abscise or persist through the June drop period. A series of experiments were carried out over several years to develop a procedure that could be used to predict the response to a chemical thinner application within 7 to 8 days after application and before thinners exhibit their final effect. The procedure developed involves tagging 105 spurs on seven individual trees distributed appropriately in the orchard. A minimum of two measurements must be made, one 3 to 4 days after application and again 7 to 8 days after application. This model requires that fruit measurement should not start before fruit grow to a diameter of 6 mm and individual fruit within a spur should be numbered and identified. The model is based on the assumption that if fruit growth rate of a particular fruit over the measurement period is less than 50% of the growth rate of the fastest growing fruit on the tree during the same growth period, it will abscise, whereas if fruit growth rate exceeds 50% of the growth rate of the fastest growing fruit, it will persist. All data can be entered into an Excel spreadsheet and the output in the summary page gives the predicted fruit set expressed as percentage of the total number of fruit present. The strategy for crop load adjustment with chemical thinners has evolved over the years to a point where most orchardists plan and are prepared to make two or more thinner applications. The dilemma associated with this approach is to determine if additional thinner applications are necessary. Up to this point a tool designed specifically to provide this information has not been developed.

scholarly journals 297 EFFECTS OF NAA ON FRUIT SIZE OF `DELICIOUS' APPLES

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 472f-472
Author(s):  
Brent L. Black ◽  
Martin J. Bukovac ◽  
Jerome Hull
Keyword(s):  
Growth Rate ◽  
Fruit Size ◽  
Spray Application ◽  
Time Of Application ◽  
Fruit Thinning ◽  
Growing Seasons ◽  
Small Fruit ◽  
Constant Dose ◽  
Carrier Volume ◽  
Fruit Diameter

Post-bloom fruit thinning of spur-type `Delicious' with NAA may occasionally result in excessive small fruit (50 - 67 mm) not correlated with crop load. We evaluated the effect of carrier volume and time of application on incidence of small fruit over three growing seasons. A constant dose of NAA (30 g·ha-1) was applied in 230 to 2100 liter·ha-1 at about 10 mm king fruit diameter (KFD). Amount of NAA-induced small fruit differed from year to year, but there was no significant effect of carrier volume in any given year. NAA (15 mg·liter-1) was applied as a dilute spray at 5 to 22 mm KFD. Time of application influenced fruit size distribution at harvest in only one of three years. The incidence of small fruit appeared more closely related to temperature during spray application than to carrier volume or time of application. The effect of NAA on growth rate of king fruit with minimal competition (branches hand thinned, no lateral fruit) was determined over the first month after thinning. There was no pronounced effect of NAA on post-treatment growth rate. In a related study, NAA caused a significant decrease in fruit size when two or more fruit were competing on the same spur, while fruit size in the absence of intra-spur competition was not significantly reduced.

In-Situ Dual-Wavelength Ellipsometry and Light Scattering Monitoring of Si/Si1−xGex Heterostructures and Multiuantum Wells

1993 ◽  
Vol 324 ◽  
Author(s):  
C. Pickering ◽  
D.A.O. Hope ◽  
W.Y. Leong ◽  
D.J. Robbins ◽  
R. Greef
Keyword(s):  
Growth Rate ◽  
Light Scattering ◽  
Laser Light ◽  
Growth Period ◽  
Laser Light Scattering ◽  
Heterojunction Bipolar Transistor ◽  
Dual Wavelength ◽  
Multi Quantum Well ◽  
Refractive Index Data

AbstractIn-situ dual-wavelength ellipsometry and laser light scattering have been used to monitor growth of Si/Si1−x,Gex heterojunction bipolar transistor and multi-quantum well (MQW) structures. The growth rate of B-doped Si0 8Ge0.2 has been shown to be linear, but that of As-doped Si is non-linear, decreasing with time. Refractive index data have been obtained at the growth temperature for x = 0.15, 0.20, 0.25. Interface regions ∼ 6-20Å thickness have been detected at hetero-interfaces and during interrupted alloy growth. Period-to-period repeatability of MQW structures has been shown to be ±lML.

scholarly journals NONLINEAR AGROMETEOROLOGICAL MODELS FOR ESTIMATING LYCHEE FRUIT GROWTH

2017 ◽  
Vol 39 (2) ◽  
Author(s):  
LUCAS EDUARDO DE OLIVEIRA APARECIDO ◽  
RAFAEL BIBIANO FERREIRA ◽  
GLAUCO DE SOUZA ROLIM ◽  
BIANCA SARZI DE SOUZA ◽  
PAULO SERGIO DE SOUZA
Keyword(s):  
Fruit Development ◽  
Dry Matter ◽  
Potential Evapotranspiration ◽  
Climatic Conditions ◽  
Fruit Growth ◽  
Multivariate Models ◽  
Degree Days ◽  
Fresh Matter ◽  
Meteorological Elements ◽  
Fruit Diameter

ABSTRACT The influence of climate on the development of lychee fruit is complex, but few studies have discussed the problem. We developed agrometeorological models for simulating the development of fruit fresh matter (FM), fruit dry matter (DM), fruit length (LE), fruit diameter (DI), fruit volume (VO), and fruit number per cluster (FN) of the “Bengal” lychee cultivar as functions of climatic conditions. We conducted three analyses: (a) the influence of mean meteorological elements on the rates of fruit growth, (b) estimation of fruit development by the agrometeorological models using sigmoidal adjustments, and (c) simulation of fruit development using multiple nonlinear regression of two meteorological elements to improve the accuracy. A rate of water deficit (WD) near 5 mm d-1 maximised FM, DM, LE, DI, and VO. Increases in potential evapotranspiration (PET), degree days (DD), and actual evapotranspiration (AET) were correlated with increases in VO and decreases in LE and NF. Models estimating fruit development indicated that the accumulation of WD, PET, AET, and DD had sigmoidal relationships with all variables of fruit growth except FN. FN decreased as WD, PET, AET, and DD increased. The adjusted multivariate models were accurate, with the largest error of 6.45 cm3 (VO). The best models were: FM = f(SWD, DD), LE = f(SAET, DD), DI = f(SWD, DD), VO = f(SWD, DD), and FN = f(SAET, WD).

Biology of Acacia pulchella R.br. With Special Reference to Symbiotic Nitrogen Fixation

1981 ◽  
Vol 29 (5) ◽  
pp. 579 ◽  
Author(s):  
D Monk ◽  
JS Pate ◽  
WA Loneragan
Keyword(s):  
Plant Density ◽  
Natural Populations ◽  
Growth Period ◽  
Sand Culture ◽  
Nitrogen And Phosphorus ◽  
N Accumulation ◽  
Growing Seasons ◽  
Reduction Activity ◽  
C2h2 Reduction ◽  
Total Plant

Growth, reproduction and longevity of the fire weed Acacia pulchella var. glaberrima were examined in natural populations of known age in coastal sands in and around Perth, W.A. Dense populations (10000 plantsiha) were established after a summer burn; plant density was 30% of its initial value at 4 years. less than 8% at 13 years. Plants accumulated dry matter, nitrogen and phosphorus throughout a 13-year growth period. Seed production commenced at 2 years, reached a maximum (12000 seeds per plant per year) at 3 or 4 years declining to 2000 seedsiplant in the 13th year. Only a small fraction of the shed seed accumulated in soil under the stands. Changes in total plant N, nodule weightlplant, and C2H2 reduction capacity of detached nodules were followed in populations in their first, second and fourth growing seasons. A new set of nodules formed with the autumn rains, peak nodule mass and C2H2 reduction activity were recorded in July-October, and virtually no nodules survived the summer into a second growing season. A glasshouse study of N accumulation and C2H2 reduction by nodules in minus N sand culture gave acalibration value of 2.26 mol C2H2 : mol N2 fixed. Applying this value to data from nativepopulations, 8% of the N accumulated by first season plants, 45% of the N of second season plants and 68% of the N of fourth season plants were estimated to be derived from symbiosis. Average annual returns of N to the ecosystem were estimated at 3.9 kg/ha, probably more than half of this from N2 fixation. Progressive death of plants in the populations gave the greatest return ( 1.9 kg N per ha per yr), the remainder from litter (1 kg N per ha per yr) and shed seed ( 1 kg N per ha per yr).

Chemotype and aggressiveness evaluation of Fusarium graminearum and Fusarium culmorum isolates from wheat fields in Wisconsin

Plant Disease ◽  
2021 ◽  
Author(s):  
Brian Mueller ◽  
Carol Groves ◽  
Damon L. Smith
Keyword(s):  
Growth Rate ◽  
Fusarium Head Blight ◽  
Fusarium Graminearum ◽  
Fusarium Culmorum ◽  
Head Blight ◽  
Growing Seasons ◽  
Progress Curve ◽  
Sporulation Capacity ◽  
Derivatives Of

Fusarium graminearum commonly causes Fusarium head blight (FHB) on wheat, barley, rice, and oats. Fusarium graminearum produces nivalenol and deoxynivalenol (DON) and forms derivatives of DON based on its acetylation sites. The fungus is profiled into chemotypes based on DON derivative chemotypes (3 acetyldeoxynivalenol (3ADON) chemotype; 15 acetyldeoxynivalenol (15ADON) chemotype) and/or the nivalenol (NIV) chemotype. The current study assessed the Fusarium population found on wheat and the chemotype profile of the isolates collected from 2016 and 2017 in Wisconsin. Fusarium graminearum was isolated from all locations sampled in both 2016 and 2017. Fusarium culmorum was isolated only from Door County in 2016. Over both growing seasons, 91% of isolates were identified as the 15ADON chemotype while 9% of isolates were identified as the 3ADON chemotype. Aggressiveness was quantified by area under disease progress curve (AUDPC). The isolates with the highest AUDPC values were from the highest wheat producing cropping districts in the state. Deoxynivalenol production in grain and sporulation and growth rate in vitro were compared to aggressiveness in the greenhouse. Our results showed that 3ADON isolates in Wisconsin were among the highest in sporulation capacity, growth rate, and DON production in grain. However, there were no significant differences in aggressiveness between the 3ADON and 15ADON isolates. The results of this research detail the baseline frequency and distribution of 3ADON and 15ADON chemotypes observed in Wisconsin. Chemotype distributions within populations of F. graminearum in Wisconsin should continue to be monitored in the future.

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