scholarly journals EFFECTS OF THIDIAZURON (TDZ) ON FRUITING OF TEMPERATE TREE FRUITS

2001 ◽  
Vol 23 (3) ◽  
pp. 513-517 ◽  
Author(s):  
JOSÉ LUÍS PETRI ◽  
ENIO SCHUCK ◽  
GABRIEL BERENHAUSER LEITE

Thidiazuron (TDZ) is a phenylurea like citokinin on cell division fruit growth and fruit shape in some deciduous fruit trees. The effects of TDZ applied during flowering on apple cultivars 'Gala' and 'Fuji" were evaluated during seven growing seasons with annual applications on the same trees. The effects on pear and kiwi fruit trees were also evaluated. Every year, TDZ significantly increased fruit set and fruit weight on apple trees. The seven-year average of the fruit set from TDZ at 10 mg.L-1 was 112.7% while the control was only 51.3%. TDZ did not affect the number of clusters. The fruit weight increased 7.0% and 18.3% when the trees were sprayed with TDZ at 10 mg.L-1 and 5 mg.L-1, respectively. TDZ also increased fruit yield per tree by 28.7% and 41.8% for the 10 mg.L-1 and 5 mg.L-1 treatments, respectively. TDZ reduced the seed number per fruit and the calcium content in the flesh fruit, but increased the fruit firmness. The fruit set increased significantly on pear cultivar Packm's Triumph treated with TDZ, and reduced the seed numbers per fruit. TDZ applied at 12.5 mg.L-1 increased fruit weight by 47,4% on "Monty" kiwi.

2017 ◽  
Vol 39 (4) ◽  
Author(s):  
MATEUS DA SILVEIRA PASA ◽  
BRUNO CARRA ◽  
CARINA PEREIRA DA SILVA ◽  
MARLISE NARA CIOTTA ◽  
ALBERTO FONTANELLA BRIGHENTI ◽  
...  

ABSTRACT The low fruit set is one of the main factors leading to poor yield of pear orchards in Brazil. Ethylene is associated with abscission of flowers and fruitlets. Then, the application of ethylene synthesis inhibitors, such as AVG, is a potential tool to increase fruit set of pears. The objective of this study was to evaluate the effect of AVG, sprayed at different rates and timings, on fruit set, yield and fruit quality of ‘Rocha’ pear. The study was performed in a commercial orchard located in the municipality of São Joaquim, SC, during the growing seasons of 2014/2015 and 2015/2016. Plant material consisted of ‘Rocha’ pear trees grafted on quince rootstock ‘BA29’. AVG was tested at different rates (60 mg L-1 and 80 mg L-1) and timings [full bloom, one week after full bloom (WAFB), and two WAFB), either alone or in combination. The experiment was arranged in a randomized block design, with at least five single-tree replications. The fruit set, number of fruit per tree, yield, estimated yield, fruit weight, return bloom, and fruit quality attributes were assessed. Fruit set and yield were consistently increased by single applications of AVG at 60 and 80 mg L-1 at both one and two weeks after full bloom, without negatively affecting fruit quality attributes and return bloom.


HortScience ◽  
1991 ◽  
Vol 26 (6) ◽  
pp. 789F-789
Author(s):  
J.T.A Proctor ◽  
J.W. Palmer

The development of a complete and healthy early season canopy of spur leaves, and later addition of bourse leaves, is essential for fruit set, fruit growth and quality in apple. The present study was undertaken to evaluate the temporal role of spur leaves and bourse shoots on fruit set, growth and return bloom in three apple cultivars and fruit Ca Level at harvest in two cultivars. Individual flowering spurs on mature wood of “Cox's Orange Pippin”, “Golden Delicious” and “Crispin” apple trees were modified by removing the spur leaves, the bourse shoot, or both, at full bloom and two, four and eight weeks afterwards. Leaf removal reduced fruit set, yield (as fruit number and not size), fruit calcium level at harvest, and return bloom. Defoliationhad its greatest effect on fruit calcium level when done early in the season and plots of this against treatment time suggested a curvilinear relationship. Return bloom was dependent on the presence of the bourse shoots on the spur but not on spur leaves. Return bloom of all three cultivars declined with the number of fruitlets per spur four weeks after full bloom.


HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 797D-797
Author(s):  
Alireza Talaie* ◽  
Ahmad Ershadi ◽  
Ali Vezvaei

In order to study pollination and fruit set and determine the best pollinizers for two Iranian apple cultivars, Golab Kohanz and Shafiabadi, experiments were conducted during two years. Different pollen sources including pollen of cultivars Golab Isfahan, Golab Kohanz, Mashhad Nouri, Shafiabadi and also open pollination were used. Pollen sources had significant effects on fruit set, fruit weight, diameter, shape, dry weight, total soluble solids (TSS), sugar and seed contents in cv. Golab Kohanz. Trees pollinated by pollen of Shafiabadi had highest fruit set, fruit weight, diameter, shape, dry weight, TSS., sugar, and seed content. Pollen sources significantly affected fruit set, fruit weight, diameter, shape, and seed content in cv. Shafiabadi. The highest fruit set, fruit weight, diameter, and seed content was resulted from flowers pollinated by Golab Kohanz. Golab Kohanz and Shafiabadi had 3.3% and 0.5% fruit set from self pollination, respectively, and seemed to be completely incompatible. Fruit resulted from self pollination were generally small and of low quality. Regardless to fruits obtained from pollination, different pollen sources had small effects on fruit quality. The results indicated that cvs. Shafiabadi and Mashad Nouri are the best pollinizers for Golab Kohanz and Golab Kohanz was superior pollinizers for Shafiabadi.


2005 ◽  
Vol 15 (4) ◽  
pp. 886-895 ◽  
Author(s):  
S.S. Miller ◽  
R.W. McNew ◽  
B.H. Barritt ◽  
L. Berkett ◽  
S.K. Brown ◽  
...  

Cultivar and planting site are two factors that often receive minimal attention, but can have a significant impact on the quality of apple (Malus ×domestica) produced. A regional project, NE-183 The Multidisciplinary Evaluation of New Apple Cultivars, was initiated in 1995 to systematically evaluate 20 newer apple cultivars on Malling.9 (M.9) rootstock across 19 sites in North America. This paper describes the effect of cultivar and site on fruit quality and sensory attributes at a number of the planting sites for the 1998 through 2000 growing seasons. Fruit quality attributes measured included fruit weight, length: diameter ratio, soluble solids concentration (SSC), titratable acidity (TA), flesh firmness, red overcolor, and russet. Fruit sensory characteristics rated included crispness, sweetness, and juiciness, based on a unipolar intensity scale (where 1 = least and 5 = most), and acidity, flavor, attractiveness, and desirability based on a bipolar hedonic scale (where 1 = dislike and 5 = like extremely). All fruit quality and sensory variables measured were affected by cultivar. The two-way interaction of cultivar and planting site was significant for all response variables except SSC, TA, russet, crispness, and sweetness ratings. The SSC: TA ratio was strongly correlated with sweetness and acidity sensory rating, but was weakly correlated with flavor rating. The results demonstrate that no one cultivar is ideally suited for all planting sites and no planting site is ideal for maximizing the quality of all apple cultivars.


HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 534F-535
Author(s):  
Ejaz Mohammad Ansari ◽  
Frank B. Matta ◽  
Taqueer Abbas ◽  
Mohammad Baquir

The influence of bloom chemical thinner Wilthin on three apple cultivars (Royal Gala, Blushing Gold, and Ultra Gold) was investigated. Two experiments were conducted in 1995 and 1996 to determine the effect of Wilthin at 0%, 0.5%, 1.0%, and 1.5% on fruit length, fruit diameter, fruit weight, yield, juice pH, acidity, SSC, sucrose, glucose, fructose, fruit firmness, and fruit set. Wilthin reduced fruit set of `Royal Gala', `Ultra Gold', and `Blushing Golden' and increased yield of all cultivars. In general, Wilthin increased fruit weight of `Royal Gala', `Ultra Gold', and `Blushing Golden' both years. Wilthin increased fruit length and diameter of `Royal Gala' and `Ultra Gold', but it did not affect fruit length of `Blushing Golden'. Wilthin increased fruit juice pH of `Royal Gala', `Ultra Gold', and `Blushing Golden' during both years. Wilthin decreased fruit juice acidity of `Royal Gala', `Ultra Gold', and `Blushing Golden'. In 1995, Wilthin increased SSC of `Royal Gala' and `Ultra Gold'. In 1996, Wilthin did not effect SSC of `Royal Gala' and `Blushing Golden', but increased SSC of `Ultra Gold'. Wilthin increased sucrose concentration of `Royal Gala', `Ultra Gold', and `Blushing Golden'. Wilthin did not effect fruit juice glucose concentration of `Royal Gala' but increased fruit juice glucose concentration of `Ultra Gold' and `Blushing Golden'. Wilthin did not influenced fructose content of `Royal Gala' and `Blushing Golden' apples. Wilthin increased fructose contents of `Ultra Gold'. Accel increased fruit firmness of `Royal Gala', `Ultra Gold', and `Blushing Golden' and increased fruit firmness of `Royal Gala'.


2015 ◽  
Vol 4 (4) ◽  
pp. 86-99 ◽  
Author(s):  
O. Al-Halabi ◽  
B. Muzher

This work was aimed to evaluate genetic diversity among five local and six introduced apple cultivars in the germplasm which located in the South of Syria based on 29 morphological characters of leaf and fruit. The analysis of variance showed significant differences at P < 0.05 for all measured parameters, however the mean values of Limb length and width, fruit weight, length, and width indicated to a wide range of diversity between local and introduced cultivars, that the introduced cultivars have mostly the highest mean value while the local cultivars have the lowest mean values, that clearly found in the local apple cultivar Ksairi (K) which revealed the lowest mean value of fruit weight (FW), fruit length (FL) and fruit diameter (FD) in the comparison with all studied cultivars. Likewise, principal component analysis (PCA) was used and the first 4 principal components accounted for 76.4% of the total variance, with eigen values 29.2%, 18.8%, 16.9% and 11.5% respectively. The main important characters in PC1 are correlated with the high mean value of width of stalk cavity (WP), fruit weight (FW), fruit diameter (FD), fruit length (FL), core length (CL), width of calyx cavity (WC), core width (CW), depth of stalk cavity (DP), stalk diameter (SD), seed width (SeW) and leaf margin (LM). PC2 discriminated among cultivars depending on Fruit shape (FS), leaf shape (LS), over color (OC), maturity time (MT), core shape (CS), limp length (LL) and leaf base (LB) which were able to differentiate between all studied cultivars . PC3 is correlated with the high mean value of Stalk length (SL), titratable acidity (TA), total sugar (TS), and total soluble solids (TSS). PC4 is correlated with the high mean value of depth of calyx cavity (DC), leaf apices (LA) and fruit cross section (FCS). Cluster analysis was also used that divided the studied cultivars into two clusters, the first cluster included all local apple cultivars, in addition to Leaz Golden (LG) cultivar, however AbouGhabra (AG) and Ksairi (K) cultivars revealed the highest similarity, which have the same fruit shape(FS), background color (BC), core shape (CS), fruit cross section (FCS), leaf shape (Ls) and leaf margin (LM). While the second cluster included all the other introduced cultivars.International Journal of Environment Vol.4(4) 2015: 86-99


Plant Disease ◽  
2002 ◽  
Vol 86 (12) ◽  
pp. 1357-1362 ◽  
Author(s):  
W. F. Wilcox ◽  
B. A. Latorre

Five identified and two unidentified Phytophthora spp. were isolated from diseased roots of dead or declining red raspberry (Rubus idaeus L.) plants sampled from 18 plantations along a >1,000-km north-south axis in Chile. The array of Phytophthora spp. isolated was strongly associated with geographical location. P. fragariae var. rubi was recovered from 75 and 60% of the plantations in the southern (40°16′ to 40°53′ S latitude) and central (34°35′ to 37°23′ S latitude) production sectors, respectively, but was not recovered from any plantation in the northern sector (32°43′ to 33°45′ S latitude). Similarly, P. megasperma and P. gonopodyides were recovered from multiple plantations in the southern and central sectors but were not recovered in the northern sector. In contrast, P. cryptogea was recovered from 80% of the plantations in both the northern and central sectors but not from any plantation in the south, whereas P. citricolawas isolated from diseased plants in all sectors. In subsequent pathogenicity trials, P. citricola, P. cryptogea, and an unidentified Phytophthora sp. were equally and highly virulent on ‘Heritage’ red raspberry in each of three greenhouse experiments. The other species were less virulent in the experiment when soil temperatures were highest (mean weekly maximum = 27.5°C) relative to the other two experiments when temperatures were more moderate (mean weekly maxima of 19.9 and 23.7°C). Isolates identified as P. cryptogea were very similar to P. cryptogea isolates recovered previously from kiwi fruit in Chile and from deciduous fruit trees in California with respect to morphological characters and electrophoretic banding patterns of soluble mycelial proteins. Using the same criteria, isolates identified as P. gonopodyides were very similar to isolates recovered earlier from deciduous fruit crops in New York, which previously were identified as P. cryptogea sensu lato but are hereby reclassified as P. gonopodyides.


HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 482D-482 ◽  
Author(s):  
David E. Davis ◽  
John A. Barden ◽  
Ross E. Byers

In 1997 and 1998, we determined the effects of defoliation on return bloom and fruit set following a light cropping year. In one study, `Braeburn' trees were hand-thinned to a crop density (CD) of 3 fruit/cm 2 trunk cross sectional area (TCSA) in late May 1997, and then either completely defoliated or half of the tree defoliated by hand on one of five dates between June and Sept. 1997. Compared to a nondefoliated control, both whole and half-tree defoliation on all dates reduced fruit count and yield efficiency (kilograms per square centimeter of TCSA) and affected fruit weight, starch, firmness, and soluble solids in 1997. In 1998, return bloom and fruit set were reduced by most 1997 defoliation treatments. Compared to other dates, defoliation on 3 July caused the greatest reduction in return bloom in both whole and half-defoliated trees. In another study, `Braeburn' trees were hand-thinned to a CD of 5 in late May 1998; complete defoliation by hand on 1, 15, or 29 July reduced return bloom and fruit set in 1999; the 1 July treatment resulted in zero return bloom. `Golden Delicious' and `York' trees were thinned to a CD of 3 in late May 1998 and were hand-defoliated on 21 July or 12 August by removing every other leaf or removing three of every four leaves over the entire tree. In 1999, return bloom and spur and lateral fruit set were reduced by all defoliation treatments. Fruit set was most reduced by the 12 Aug. treatment. Fruit set for `York' was lower than for `Golden Delicious' in all cases.


Agronomy ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 760 ◽  
Author(s):  
Isabel Díez-Palet ◽  
Inmaculada Funes ◽  
Robert Savé ◽  
Carmen Biel ◽  
Felicidad de Herralde ◽  
...  

Climate change, and specifically global temperature increase, is expected to alter plant phenology. Temperate deciduous fruit trees have cultivar-specific chill and heat requirements to break dormancy and bloom. In this study, we aimed to estimate chill and heat requirements (in chill portions, CP, and growing degree hours, GDH, respectively) of 25 almond (30–36 years) and 12 apple (14–26 years) cultivars grown under a Mediterranean climate. The set included early and late blooming genotypes. Long-term phenological and temperature records were analyzed by means of partial least squares (PLS) regression. The main difference between early and late genotypes was chill requirement, ranging from 8.40 CP of early genotypes to 55.41 CP of extra-late genotypes. However, as chill requirements are quite easily attained by all almond cultivars in this study, year-to-year variations in actual blooming dates for each genotype are governed by variability of mean forcing temperatures. In contrast, different chill and heat combinations resulted in similar mean blooming dates for the studied apple cultivars. Mean temperature in both chilling and forcing phases determined their blooming time in the location studied. Overlaps and gaps between both phases were obtained. Despite some limitations, the PLS analysis has proven to be a useful tool to define both chilling and forcing phases. Nevertheless, since the delineation of these phases determine the total amount of CP and GDH, further efforts are needed to investigate the transition of these phases.


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