Search Results

You are looking at 1 - 4 of 4 items for :

  • Author or Editor: U.L. Yadava x
  • Journal of the American Society for Horticultural Science x
Clear All Modify Search
Authors: and

Abstract

Fifty-nine available combinations of 16 peach [Prunus persica (L.) Batsch] seedling rootstocks and four cultivars were evaluated for survival, growth, productivity, and peach tree short life (PTSL) performance of scions for 10 years (1975–1984). Rootstock influenced tree survival, cold and bacterial canker damages, root suckering, bloom date, degree of budbreak, and fruit yield. However, rootstock had little effect on bud density, fruit maturity and size, and time of autumn defoliation, and no influence on trunk circumference and bark gummosis. Cultivars differed in all characteristics except tree survival and canker damage. Tree survival was negatively correlated with budbreak, bloom date, cambial browning, Pseudomonas canker, suckering, and defoliation. Lovell rootstock had the best overall PTSL-related performance, while Siberian C had the worst. ‘Derby’ was the most desirable and ‘Hamlet’ the least of the four cultivars evaluated.

Open Access
Authors: and

Abstract

Two-year-old ‘Redhaven’ peach (Prunus persica (L.) Batsch) trees on 7 different peach seedling rootstocks growing on short-life and on non-short-life sites were examined for cold hardiness of trunks using trunk cambial browning (TCB), and cold hardiness of twigs using tests for electrolytic conductivity (EC), triphenyl tetrazolium chloride (TTC), and ninhydrin-reactive compounds (NRC). It was found that Lovell, Halford, and NA 8 rootstocks invariably imparted more cold hardiness to ‘Redhaven’ budded onto them than other rootstocks tested, whereas maximum cold injury was sustained by trees on NRL 4 rootstock. Tree mortality was higher and cold injury was more severe on the short-life site than on the non-short-life site.

Open Access
Authors: and

Abstract

Roots, shoots, and leaves of 1- and 2-year-old ungrafted plants of EM IX, VII, and I, and roots of EM XVIa, were extracted to detect an inhibitor that appears identical with abscisic acid (ABA). The extracts were coned, partially purified chromatographically, and bioassayed using the wheat coleoptile straight growth and Lepidium seed germination tests. A strongly inhibitory substance was found in both bioassays at or close to the Rf values reported for maximum ABA activity or determined with the synthetic form.

Extracts of EM IX tissue contained the highest levels of this inhibitor, presumed to be ABA. Progressively lower levels were found in extracts of EM VII, I, and XVIa, which is the same as the order of these clones in increasing vigor of grafted scions. This same order was indicated in nearly all bioassays of the 3 types of tissue extracts. Extracts of roots collected in early spring after overwintering either in storage or out-of-doors, in midsummer, and in the fall after cessation of growth all placed the clones in the same order. Levels in root and leaf extracts were generally higher than in those of shoots.

The Lepidium seed bioassay appears to offer a convenient method for identification of strongly or semi-dwarfing individuals or clones. Leaves offer an obvious advantage over shoots or roots.

Open Access

Abstract

The reliability, capability to predict survival, and convenience of 5 cold hardiness tests — triphenyl tetrazolium chloride reduction (TTC), electrolytic conductance (EC), ninhydrin-reactive compounds (NRC), trunk cambial browning (TCB), and bacterial canker development (BCD) — were evaluated using previous season's twigs of ‘Redhaven’ peach (Prunus persica (L.) Batsch) during the 1976-77 dormancy season. TTC, NRC, and EC were all significantly correlated with TCB as well as percent tree survival (PTS) in the field, and thus proved to be quantitative, reliable and capable of predicting survival at a later date. No statistical correlation was found between BCD and other hardiness tests.

Open Access