Table 2 - uploaded by Leonardo Duarte Pimentel
Content may be subject to copyright.
Number of days to start germination and accumulated chilling units (CU) for germination of 50% and 100% of seeds of 18 peach cultivars and one nectarine cultivar
Source publication
Em regiões de clima subtropical, os modelos e métodos propostos para avaliação da necessidade de frio das fruteiras de clima temperado não apresentam, muitas vezes, resultados satisfatórios. Isto demonstra a necessidade do desenvolvimento de alternativas para se estimar a necessidade de frio dessas plantas. Este trabalho teve como objetivo analisar...
Contexts in source publication
Context 1
... of variance showed that there were significant differences in the number of days required for the onset of germination and the accumulated chilling units needed to achieve 50% and 100% germination of the different cultivars. This shows that there is variability between the cultivars for these variables (Table 2). Variability is the necessary raw material used by the breeder in any breeding program. ...
Context 2
... (1990Pérez-Gonzalez ( , 1997 showed that the time to reach the onset of germination (less than 35 days of stratification) has been used in the pre-selection and selection of genotypes with low winter chilling requirement in the subtropics. Considering this criterion, in this work, the cultivars Aurora-1, Alô Doçu- ra, Campinas 1, Josefina, Ouromel, Real, Relíquia, Talismã, Biuti, Rei da Conserva, Colibri and Topázio, all starting germination before 35 days could be selected (Table 2). Our findings demonstrate the similar chilling requirements of these cultivars as already described by Antunes (1985). ...
Similar publications
The term adaptability refers to the ability of a genotype to respond favorably to environmental spur, while stability is the predictability of genotypic behavior. Therefore, the objective was to select Prunus rootstock cultivars with greater adaptability and genotypic stability for subtropical environmental conditions using the HMPRVG method. The e...
The SQUAMOSA promoter binding protein (SBP)-box proteins are plant-specific transcriptional factors in plants. SBP TFs are known to play important functions in a diverse development process and also related in the process of evolutionary novelties. SBP gene family has been characterized in several plant species, but little is known about molecular...
Peach crop area in Uruguay has seen a reduction over the last years. A possible reason for this is a decrease in return. Consequently, this paper aims at studying whether or not peach growing is a profitable activity for growers. Data supporting this study came from Mercado Modelo of Montevideo and the Ministry of Livestock, Agriculture and Fisheri...
Rootstock micropropagation has been extensively used as an alternative to propagation by cuttings. Although studies have recently been conducted on other species, no conclusive reports have been published on the effect of rootstock micropropagation on the field performance of fruit trees. Here, we present the results of a five-year study of peach v...
Peach was domesticated in China more than four millennia ago and from there it spread world-wide. Since the middle of the last century, peach breeding programs have been very dynamic generating hundreds of new commercial varieties, however, in most cases such varieties derive from a limited collection of parental lines (founders). This is one reaso...
Citations
... A superação da dormência física é obtida através da quebra do caroço. Para a superação da dormência fisiológica é necessário expor as sementes à condições de baixa temperatura, por período variável em função do genótipo, visando alterar a concentração dos fitormônios promotores e inibidores da germinação (Wagner Júnior et al., 2013). ...
O objetivo deste trabalho foi caracterizar o potencial germinativo de sementes de porta-enxertos de pessegueiro. O material propagativo constituiu-se de caroços das cultivares de porta-enxertos ‘Capdeboscq’ ‘Tsukuba 1’, ‘Tsukuba 2’, ‘Tsukuba 3’, ‘Okinawa Roxo’ e dos híbridos intraespecíficos de P. persica, seleções ‘NR 0280401’ (híbrido F1 derivado do cruzamento ‘Flordaguard’ x ‘Capdeboscq’), ‘NR 0080412’ (híbrido F1 derivado do cruzamento ‘Capdeboscq’ x ‘Flordaguard’), ‘NR 0050303’ (híbrido F1 derivado do cruzamento ‘Capdeboscq’ x ‘Tsukuba 1’) e ‘NR 0300402’ (híbrido F1 derivado do cruzamento ‘Flordaguard’ x ‘Nemaguard’) foram estratificadas em BOD, na ausência de luz, onde permaneceram por até 28 dias. Verificou-se que as sementes das seleções de porta-enxertos ‘NR 0280401’, ‘NR 0080412’ e da cv. ‘Capdeboscq’ requerem menor tempo para a germinação e apresentam maior percentual de sementes germinadas. Genótipos com maturação de frutos mais precoces, o período de armazenamento deve ser menor, devido à perda viabilidade, conforme verificado para ‘Okinawa Roxo’.
... Peach (Prunus persica L. Batsch) requires low temperature to break the dormancy of seeds and buds resulting in seed germination and flowering (Americo et al., 2013). The low temperature triggers internal mechanisms that change the nature and level of growth regulators involved in the dormancy's control processes (Kester et al., 1977). ...
... There was no significant difference between treatments S1B1 (17.07 O C) and S1B2 (17.05 O C) on over year combined result of mean temperature and the same is true for treatments, S2B1 and S2B2 which is 17.19 O C and 17.24 O C respectively. Although investigations have been done on the low-temperature stratification of peach seeds to overcome dormancy (Sharma & Singh, 1978;Bewley et al., 2013;Americo et al., 2013). Overall treatments located out of shade both on the flat and sunken bed recorded significantly higher temperatures followed by those treatments in the shade and the control as stated in Figure 1. ...
... Here the highest GSI is recorded for S1B1 (1.90) followed by S1B2 (1.82) even if there is no statistical difference between them. This variation might be because of the length of periods that the seeds we exposed to stratification (Finch-Savage, 2004;Rawat et al., 2010), and also be cues the genetic component that can influence entire population of seed or individual seeds within a seed lot (Geneve, 2003;Americo et al., 2013). ...
Poor germination of peach seeds is the major limiting factor for rootstock production under the Holetta condition because of the seed dormancy problem. Stratification plays an important role in shortening the dormancy and increasing the germination of peach seeds. The study aimed to find easy stratification techniques for the germination of peach seeds using shade and different bed types. The experiment was carried out at the Holetta Agricultural Research Center in two successive years of 2017 and 2018. We got seeds used for this study from peach trees, which were well adapted for the Holetta area. It was arranged in a completely randomized design with five treatments of under tree shade on a flatbed, under tree shade in sunken bed, out of tree shade on a flatbed, out of tree shade in sunken bed and refrigerator as a standard check. They put all treatments except the refrigerator under the grass shade constructed 1 m3 wide. The treatments replicated four times, and each replication contained 200 seeds. The results showed that temperature is the most important factor affecting the germination percentage of the peach seeds. Seeds sown under the temperature close to 8 0C which is in the refrigerator found to have better germination percentage (47.1%) followed by the seeds sown in the grass shade under the tree shade both on sunken (35.8%) and flatbeds (34.9%). Peach seeds stratified in the refrigerator had good germination percentage whereas survival of the seedling was better at out of tree shade in sunken bed and out of tree shade on the flatbed. Even though the germination percentage was lower and the germination speed index was higher than the refrigerator. Seeds stratified at a temperature of above 17 OC experienced a poor germination percentage.
... Many nurseries still rely on this cultivar for their fields of mother plants matrices. However, other cultivars selected specifically for use as rootstocks, such as 'Tsukuba 1', 'Tsukuba 2', 'Tsukuba 3', 'Flordaguard', 'Okinawa', 'Okinawa roxo' and 'Selection UFPel 0402', are still in the evaluation phase for use as peach rootstocks in the regions of South and Southeast Brazil [2,4,[6][7][8][9][10][11]. Fischer et al. (2013) [12], testing times of stratification and concentrations of growth regulators gibberellins (GA 4+7 ), obtained 67% germination in peach trees seeds rootstocks. ...
Background:
This study aimed to evaluate the efficiency of using the computerized imaging seed analysis system (SAS) in the biometric and morphophysiological characterization of seeds and the initial growth of seedlings from peach rootstocks.
Methods:
The experimental design was completely randomized with five replicates of 20 seeds. The variables analyzed were degree of seed humidity, length and width of seeds measured by SAS technology and manual measurements, mean germination time, germination percentage, radicle length and width, taproot length, length of the aerial part and taproot/aerial part ratio.
Results:
The highest seed length, germination percentage (100%) and lower germination time (11.3), were obtained with the cv. Capdeboscq while, 'Tsukuba 1', 2' and 3' had intermediate seedlings length, varying from 1.55 to 1.65 cm with mean germination times between 14.5 and 18.0 days and average germination percentage of 96%. The computerized analysis of images is fast and efficient for biometric evaluations such as seed width and length, as well as initial growth of peach tree seedlings. The cvs Capdeboscq, Flordaguard and Tsukuba 2 presented greater radicle width, length and a mean taproot/aerial part ratio equal to 2, as well as higher number of adventitious roots, which indicated a strong positive correlation between radicle length, taproot length and initial seedling growth.
Conclusion:
The continuity of the research will certainly allow the development of reliable procedures for other species, besides allowing the identification of wider alternatives for the use of this system for the expansion of knowledge in the areas of physiology and evaluation of the physiological potential of seeds.
... In addition, seeds of different peach cultivars can differ greatly in degree of dormancy, which is determined by physiologic factors and by the physical resistance promoted by the endocarp. In this case, exposure to cold is required to break dormancy and activate peach seed germination (Wagner Júnior et al., 2013). Seeds not exposed to the adequate conditions for overcoming dormancy may not germinate or may produce abnormal seedlings, with physiological symptoms of dwarfism. ...
The present study evaluated the germination potential of seeds from eight peach tree rootstocks under different stratification methods, aiming at the production of high quality seedlings. In the first experiment, seeds with endocarp from eight genotypes (‘Aldrighi’, ‘Capdeboscq’, ‘Flordaguard’, ‘Okinawa’, ‘Okinawa roxo’, ‘Tsukuba 1’, ‘Tsukuba 2’, ‘Tsukuba 3’) were stratified on sand and moist vermiculite, at 7 ºC for 60 days. In the second experiment, endocarpless seeds of the same genotypes were stratified on Petri dishes at 7 ºC. In the third experiment, the time at which at least 75% of the seedlings reached transplanting height (15 cm high) was verified. The endocarp was a limiting factor for seed germination of the eight rootstocks, since the highest germination percentages were 21% and 48.3% for ‘Aldrighi’ and ‘Capdeboscq’, respectively. Germination of ‘Okinawa’ was only 19.2% and 4.2%, in sand and vermiculite, respectively. Seeds stratified without the endocarp, showed 100% germination, except for ‘Flordaguard’ and ‘Tsukuba 2’ and 3’, with 93% germination. Seed mass presented a positive correlation with the germination speed index and the initial growth of the seedlings. ‘Aldrighi’ and ‘Capdeboscq’ presented more vigorous seedlings with greater growth in height, stem diameter, and Dickson quality index.
... The farm is located between coordinates 20° 40'S and 42° 31'W, at an 885 m altitude. According to Wagner Junior et al. (2013), based on Köppen's classification, the regional climate is type Cwb: subtropical/tropical altitude climate with dry winter and warm summer. Annual temperature ranges between 3 and 28 °C, and annual precipitation ranges from 1300 to 1500 mm. ...
The macauba palm (Acrocomia aculeata) has a great production potential of oil and is an important alternative to diversify agricultural production. In view of the hypothesis that the species may provide a positive contribution to the hydrological processes in a watershed, we aimed to assess the influence of the number of leaves per macauba plant on the correlation between stemflow and gross precipitation. We installed three rain gauges to monitor gross precipitation in an experimental area, and stemflow collectors on the stem of eight macauba plants therein having 10, 13, 18, and 22 leaves. Linear regression equations were obtained, which enabled us to estimate the minimum rainfall volume required for the occurrence of stemflow. A strong positive linear correlation was observed between stemflow and gross precipitation, regardless of the number of leaves per plant. The morphological characteristics of the macauba palm favor rainfall interception, relatively high stemflow values being shown even in young plants. The funnel-shaped crown enabled the conduction of large rainfall volumes to the stem, thus resulting in the occurrence of stemflow even with light precipitations.
... In temperate regions peach trees (Prunus persica L.) require exposure to chilling temperatures during the winter to overcome the rest period, after which normal bud break and development can occur (Campoy et al., 2011;Viti et al., 2010). The duration of chilling length required to bud break of a given cultivar is known as the chilling requirement of that particular cultivar (Wagner Júnior et al., 2013), and it varies greatly from 1050 h in 'Contender' to 600 h in 'LaFeliciana' (Parker and Werner, 2015). On the other hand, in subtropical and tropical regions the cultivation of peach trees is possible due to agronomic innovations and the development of low chilling cultivars, which require low exposure to chilling temperatures (100 to 200 h). ...
The objectives of this study was to develop partial least square (PLS) models using NIR spectroscopy for the determination of SSC and firmness in intact low chilling 'Aurora-1' peach fruit, and verify the influence of maturity stage and harvest season on the models to be developed (robustness). FT-NIR spectra were obtained as log 1/R with fruit harvested in 2013 at 3 maturity stages and in 2014. The spectra were collected on the background and blush colour skin areas of the each fruit. Model performance was evaluated based on the values of root mean square error for prediction (RMSEP) and coefficient of determination (RP2) obtained from validation fruit set (Kennard-Stone), and prediction fruit set (2014). PCA could not group the fruit based on blush and background skin colour, maturity stages, and harvest season. The model constructed using the external validation method obtained a RMSEVE of 1.08 % with 11 latent variables (LVS) and a RVE2 of 0.59. The prediction set, independent data, resulting in a less accurate model (RMSEP 1.04 %, Rp2 0.45 and 11 LVS). The same trend happened for determining firmness with the external validation resulting in better model with RMSEVE 9.51N and RVE2 of 0.40 and the prediction set with RMSEP of 13.2N, RP2 0.40 with 7 LVS. The NIR spectroscopy showed to be a potential analytical method to determine SSC and firmness of intact low chilling 'Aurora 1' cultivar. However, it is necessary to optimize the models in other to reduce the prediction errors.
