Abstract
‘Veeglo’ is an attractive, high quality peach (Prunus persica (L.) Batsch) that matures during the last week in August, 9 days after ‘Redhaven’. Assessments indicate typical, moderate susceptibility to perennial canker (Leucostoma spp.) and moderate resistance to bacterial spot (Xanthomonas pruni (E.F. Smith) Dows.). ‘Veeglo’ was introduced to satisfy the requirement for a high quality fresh market or home preserving peach maturing between Redhaven and Loring, and adapted to climatic conditions in southern Ontario, Canada.
Abstract
‘Jerseyglo’ is a large, firm yellow-fleshed freestone peach [Prunus persica (L.) Batsch] for the fresh market. The fruit ripens with ‘Jerseyqueen’, ‘Redskin’, and ‘Elberta’. It was named and released in 1979 in order to provide a large, attractive, firm-fleshed peach in this season with moderate levels of flower bud hardiness and resistance to bacterial spot [Xanthomonas campestris pv. pruni (Smith) Young et at.]. ‘Jerseyglo’ is recommended as a replacement for ‘Jerseyqueen’.
Abstract
‘Summerglo’ is a large, yellow-fleshed freestone peach [Prunus persica (L.) Batsch] for the fresh market. The fruit ripens approximately one week after ‘Redhaven’. It was named and released in 1978 to meet the need for a large peach in this season. ‘Summerglo’ leaves and fruit are susceptible to bacterial spot [Xanthomonas campestris pv. pruni (Smith) Young et al.]. Flower bud hardiness is similar to or slightly better than ‘Loring’.
Bell pepper (Capsicum annuum) seedlings treated with various biological preparations exhibited increased root and shoot growth both in the greenhouse and during subsequent field establishment. Early fruit set and pod development showed signs of possible yield improvement by the treatments, but treatment differences were not apparent at first harvest. Data from subsequent harvests did show yield increases with some preparations. Treatment organisms appeared to activate or induce systemic resistance to bacterial spot (Xanthomonas campestris) infestation though not to the level shown by Actigard (Novartis). Crop/treatment response under soil solarization, fumigation, and compost amended conditions will be discussed.
Abstract
‘Hargrand’ is an exceptionally large, firm-fleshed apricot (Prunus armeniaca L.) suitable for the fresh market, home canning and commercial processing, especially as puree for baby food. The tree is cold hardy and productive and tolerant to perennial canker (Leucostoma spp.). The fruits are moderately resistant to brown rot (Moniliniafructicola [Wint.] Honey), bacterial spot (Xanthomonaspruni [E. F. Sm.] Dows.) and skin cracking. ‘Hargrand’ ripens in the midseason with ‘Veecot’ and is being introduced for the Ontario fresh market to meet the need for better dual purpose cultivars in this season. It should be adapted to regions where ‘Goldcot’ and ‘Veecot’ are successfully grown.
Abstract
‘Jerseydawn’ is an early-ripening, yellow-fleshed, semi-freestone peach [Prunus persica (L.) Batsch] for the fresh market. The fruit ripens 10-14 days before ‘Redhaven’ and was introduced to meet the need for a quality peach in this season. The tree is of medium vigor and is productive. The leaves and fruit are resistant to bacterial spot [Xanthomonas campestris pv. pruni (Smith) Young et al.]. Flower bud hardiness appears to be slightly less than that of ‘Redhaven’. Split pit has not been a problem. ‘Jerseydawn’ is performing well in trials at Geneva, N.Y.; East Lansing, Mich.; and throughout New Jersey.
Abstract
A wick bioassay was developed to screen peach [Prunus persica (L.) Batsch] shoot cultures for resistance to bacterial spot [Xanthomonas campestris pv. pruni (E. F. Sm.) Dows)]. Three weeks after inoculation, the number of colony forming units (CFU) from 1-cm stem sections excised from highly susceptible cultivars was significantly greater than CFU from several resistant cultivars. Neither growth regulators nor the length of time that shoots were maintained in vitro prior to inoculation significantly influenced the response of these cultivars to bacterial leaf spot. This technique should be useful in screening for somaclonal variants obtained from peach cell cultures.
`White Rock' and `White County' fresh market peaches (Prunus persica (L.) Batsch) were released in 2004 by the University of Arkansas Agricultural Experiment Station. These cultivars join `White River' as recent products of the peach breeding program which is based at the University of Arkansas Fruit Substation, Clarksville. Both cultivars are sub- or low-acid types and have white flesh. `White Rock' ripens at on average 25 June, and is very firm at maturity. Average fruit weight was 142 g with 12% soluble solids and light white peach flavor. `White County' ripens on average 14 July. It is large fruited with average weight of 258 g and maintains firmness until full maturity. The fruits are freestone with an excellent white peach flavor. Both cultivars show good bacterial spot resistance although occasional lesions are seen on leaves. These new cultivars offer additional white peach cultivar choices for the mid-South and other areas of similar climate.
Abstract
Pesticides were applied to ‘Rio Grande’ peach [Prunus persica (L.) Batsch] trees at recommended rates from bloom to harvest using three sprinkler configurations on a center pivot and an air-blast sprayer. Fruit scab infection rates with a patented sprinkler configuration (Piggy-back) that has spray nozzles mounted on a lower truss rod of the center pivot were equivalent on 12 and 23 June 1987 to those with the air-blast sprayer. Scab infection rates for standard impact-nozzles and for a deflector nozzle configuration were equivalent to each other, and tended to be lower than the infection rate for the unsprayed fruit, but higher than the rate for the air-blast sprayer or piggy-back configuration. Brown rot, bacterial spot, and insect catfacing (the other fruit defects observed at harvest) were independent of the method of pesticide application. It may be feasible to chemigate peach orchards with center-pivot irrigation systems.
A pathogenic strain of Xanthomonas campestris pv. vesicatoria, causal agent of bacterial spot of tomato (Lycopersicon esculentum Mill.), was genetically engineered to bioluminesce. In planta growth of the bioluminescent strain was similar to that of its parental strain. Movement and growth of the bioluminescent strain in susceptible tomato seedlings after wound inoculation was followed over time with a liquid-N-cooled, charge-coupled device camera. Highly significant differences in bioluminescent bacterial growth were observed in the four tomato cultivars used. Systemic bacterial movement was most pronounced in `Sunny', which showed population development not only at the inoculation sites but also on several sites in the leaves and at the leaf margins. Bacterial bioluminescence levels in `Campbell 28' remained significantly lower than those observed in `Walter' and `Sunny'. The technique offers unique possibilities for studying host-pathogen interactions and bacterial pathogenesis.