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Although growth regulators of the auxin group are normally used to induce rooting of cuttings, in recent years, research has been of interest to obtain alternative methods for the induction of rhizogenesis in cuttings of plants with difficult vegetative propagation, such as Peach tree cv. ‘Chimarrita'. This makes the Cyperus rotundus L. a large-scale plant found in much of the world, an alternative for the induction of rooting in cuttings, because it has phenolic compounds that have a synergistic effect with the endogenous auxin. The objective of this study was to evaluate the rooting capacity of hardwood peach cuttings with the application of different concentrations of aqueous extract of C. rotundus L. in comparison with the application of the plant growth regulator indole- 3-acetic acid. The treatments consisted of different concentrations of the aqueous extracts of roots and shoots of C. rotundus L. and the growth regulator indole-3-acetic acid. The percentage of live cuttings, rooted cuttings, callus, and the length of roots and dry matter of the root system were evaluated. The aqueous extract of shoot and root system of C. rotundus L. does not promote the rooting of hardwood peach cuttings cv. ‘Chimarrita' within 90 days. The 500 mg L-1 concentration of indole-3-acetic acid promotes greater rooting of the hardwood peach cuttings. [ABSTRACT FROM AUTHOR]

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 °C for 60 days. In the second experiment, endocarpless seeds of the same genotypes were stratified on Petri dishes at 7 °C. 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. [ABSTRACT FROM AUTHOR]

This study aimed at determining and correlating the main morphometric characteristics of fruits and seeds with the germination potential and vigor of eight peach rootstocks. The experimental design was completely randomized, with four replications of 50 seeds per treatment. The analyzed variables were: length, width, thickness, fresh mass of fruit and seeds, moisture content of seeds, percentage of seeds attacked by fungi and intact seeds, germination percentage, germination speed index (GSI) and mean germination time (MGT). The Capdeboscq, Aldrighi and Tsukuba 1 cultivars showed higher values of length, width, thickness and fresh mass of seeds compared to other cultivars, presenting a relationship with the later period of fruit ripening. Regardless of the fruit ripening time, the germination percentage was high, ranging between 93% and 100% for all cultivars. In addition, the fresh mass of fruits has showed a high positive correlation with the fresh mass of seeds for the eight evaluated peach rootstocks. The GSI and MGT have a high relationship with the fresh mass of seeds. [ABSTRACT FROM AUTHOR]

Among the main pathogens infecting temperate fruit trees are Prune dwarf virus, Apple mosaic virus and Grapevine leafroll-associated virus 1. In this work the detection and molecular characterization of the coat protein genes of isolates from these viral species were carried out. Total RNA was extracted from peach, apple and grapevine leaves and RTPCR reactions were performed using specific primers to each virus. The amplified cDNA fragments were cloned and sequenced. High identities were observed between coat protein nucleotide sequences of Brazilian isolates of PDV, ApMV and GLRaV-1 and isolates from other countries, independently from geographic origin and host. Coat protein molecular weights of these viruses were estimated by Western blot to be ca. 24kDa (PDV), 26kDa (ApMV) and 39kDa (GLRaV-1). [ABSTRACT FROM AUTHOR]