Ilarviruses: Evidence for Rapid Spread and Effects on Vegetative Growth and Fruit Yields of Peach Trees

Plant Disease ◽  
1992 ◽  
Vol 76 (1) ◽  
pp. 71 ◽  
Author(s):  
J. K. Uyemoto
2018 ◽  
Vol 7 (2) ◽  
pp. 99-114
Author(s):  
Abdaallah El-Kharafen ◽  
Hany El-Alakmy ◽  
Roqia Ahmed ◽  
Mohamed Sourour ◽  
Mohamed ElDeep

1977 ◽  
Vol 28 (3) ◽  
pp. 441 ◽  
Author(s):  
PR Smith ◽  
TF Neales

The vegetative growth of young peach trees was reduced greatly in the growing season following a dual infection with Prunus necrotic ringspot and prune dwarf viruses which caused the disease known as 'peach rosette and decline'. Ninety-two days after bud burst, the dry weight and leaf area of cv. Elberta scions were reduced by c. 60% as a result of infection, while the reduction in cv. Golden Queen was about 93%. The latter cultivar thus appears to be the less tolerant of infection by this virus disease.


1984 ◽  
Vol 11 (2) ◽  
pp. 49 ◽  
Author(s):  
IR Dann ◽  
RA Wildes ◽  
DJ Chalmers

The distribution of current assimilates between competing zones of potential growth in the peach tree (Prunus persica (L.) Batsch) was studied using limb girdling, which altered the balance between reproductive growth and vegetative growth in a similar manner to the aging process. Fruit matured earlier, and leaf senescence and abscission were advanced in girdled limbs. which supported normal fruit loads but had only half the leaf area. Lateral growth and secondary thickening were reduced by 50% but vegetative growth approached normal rates at times when fruit growth was minimal, indicating that girdling reduced the ability of vegetative growth to compete with reproductive growth for assimilates. Starch and soluble sugars did not accumulate above the girdles. The data are consistent with the hypothesis that girdling alters the balance between endogenous growth regulators which favour either vegetative or reproductive development. We suggest that the initial effects on the girdled limb are attributable to accumulation of growth regulators produced above the girdle. The reduced flow of growth regulators to the roots eventually results in lowered levels of root-produced hormones which subsequently causes effects throughout the tree.


HortScience ◽  
1993 ◽  
Vol 28 (3) ◽  
pp. 192-194 ◽  
Author(s):  
R. Fernández-Escobar ◽  
D. Barranco ◽  
M. Benlloch

Chlorotic `Manzanillo' olive (Olea europaea L.) trees and `Maycrest' peach [Prunus persica (L.) Batsch] trees were injected with Fe solutions using an apparatus that consisted of a plastic injector and a pressurized latex tube containing the solution to be injected. Injections were made on various dates from Sept. 1987 to July 1988. All treatments increased chlorophyll content compared to that of the control. Ferrous sulfate was the most effective Fe compound in alleviating chlorosis; its effect lasted for two seasons in peach and for at least three seasons in olive. Also, ferrous sulfate increased vegetative growth and affected cropping the year following injections. Ferrous sulfate at 0.5% to 1% is recommended to reduce the risk of foliar burning. The injection method effectively introduced Fe compounds into olive and peach trees.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 549a-549
Author(s):  
R.S. Johnson ◽  
R.C. Rosecrance ◽  
H.L. Andris

Despite early studies that suggested foliar urea was ineffective in supplying nitrogen to peach trees, recent studies have shown rapid uptake of low biuret urea by peach leaves and subsequent mobilization to perennial tree parts. Labeled nitrogen experiments have demonstrated the distribution of N among organs to be very similar whether the N is supplied from foliar urea or from soil-applied fertilizer. However, questions still remain concerning the long-term productivity of trees treated repeatedly with foliar urea. Our first experiment was conducted on an early ripening peach, which generally requires about 100 kg N/ha applied to the soil. The treatment to replace all soil applied N with two or three foliar applications of urea in the fall resulted in similar N distribution throughout the tree and equal vegetative growth. However, fruit size was consistently smaller than the soil-fertilized control over a 3-year period. Our second experiment, conducted on the same variety, imposed a treatment to supplement about half the soil applied fertilizer with fall foliar urea applications. This treatment was able to maintain fruit size and yield over a 2-year period. Furthermore, vegetative growth was reduced compared to the soil-fertilized control, suggesting foliar urea may be a useful tool to help manipulate the distribution of growth between reproductive and vegetative processes.


Sign in / Sign up

Export Citation Format

Share Document