Solanum lycopersicoides is a valuable genetic resource for tomato (Lycopersicon esculentum) genetic improvement. However, there are few reports on its agronomic traits such as disease resistance and cold tolerance. In this paper, the resistance to cucumber mosaic virus (CMV) and leaf mold (Cladosporium fulvum Cooke) and cold tolerance of five lines of S. lycopersicoides were studied through investigation of disease inoculation and electrolyte leakage analysis. The results showed that S. lycopersicoides was highly resistant or immune to CMV and leaf mold and more tolerant to low temperature than L. esculentum. This study is helpful for the genetic improvement of tomato by using S. lycopersicoides as breeding materials.
Lingxia Zhao, Chengxiang Qiu, Jingfu Li, Yourong Chai, Guoyin Kai, Zhugang Li, Xiaofen Sun and K.X. Tang
Lisa J. Rowland, Elizabeth L. Ogden, Mark K. Ehlenfeldt and Rajeev Arora
blueberry genotypes in the combined-year (2002 and 2003) field study. RATE OF COLD ACCLIMATION UNDER FIELD CONDITIONS In a more recent study, we extended our cold tolerance measurements from October through midwinter comparing acclimation
Carolyn F. Scagel, Richard P. Regan, Rita Hummel and Guihong Bi
necrosis in green ash was associated with tree N status and observed that it was more influenced by fertilizer type than by N application rate ( Scagel et al., 2010 ). The specific relationships among cold tolerance, plant N status, fertilizer formulations
June Liu, Zhimin Yang, Weiling Li, Jingjin Yu and Bingru Huang
( Duncan and Carrow, 1999 ). Improving cold tolerance of warm-season turfgrasses such as seashore paspalum is important to expand the range of use and extend the growing season throughout cooler climates. Limited progress has been made in the improvement of
Lixin Peng, Mingqi Wang and Weijian Liang
Cold tolerance/resistance of 41 hazelnut hybrid strains was investigated by evaluating electrolyte seepage velocity, recovering growth, and tissue browning for the tested cold temperatures. Results demonstrated that electrolyte seepage velocity of all tested strains was faster as temperatures dropped down. The S curve relationship was found between seepage velocity and temperature. Turning point temperature used as the half deadly injured index (LT50) was developed using a logistic equation. The mean LT50 and temperature causing tissue browning were excellent indexes to predict cold tolerance/resistance. After treated at –30 or –35 °C and then evaluated for their recovering growth, 10 cold-resistant hybrid hazelnut strains were developed. These hybrids are being tested for regional adoption and will be released as commercial cultivars.
Timothy K. Broschat
The relationship between fertilization and cold tolerance of plants is a confusing one. Plant nutrition involves a number of different elements, each of which may affect a plant's cold tolerance in a different manner. Most studies on fertility
Danqing Li, Jiao Zhang, Jiaping Zhang, Kang Li and Yiping Xia
)]. Longer color retention has been associated with poorer cold tolerance in a number of plants ( Okeyo et al., 2011 ; Qian et al., 2001 ; Schwab et al., 1996 ), which makes it hard to selectively breed for cultivars with an extended green period and strong
J.R. Hotchkiss, P. Revilla and W.F. Tracy
Cold tolerance useful for sweet corn improvement may be present in open-pollinated (OP) cultivars. Cold tolerance in sweet corn is the ability to germinate, emerge, and grow under low temperatures. The cold tolerance of 35 open-pollinated sweet corn populations and controls was measured by growing the entries under 14 °C day/10 °C night in growth chambers. The same entries were grown under warm (24 ± 2 °C) conditions in a greenhouse. Traits measured included percent and time to emergence, seedling color, and seedling root and shoot dry mass. Respective repeatability estimates calculated from mean squares were 0.08, 0.33, 0.33, 0.50, and 0.60 for these traits. Entries were ranked separately in each environment based on their performance using a rank-summation index. Differences in cold tolerance existed among the entries. Emergence ranged from 75% to 100% among the entries, with a mean of 90.9%. Time to emergence ranged from 16.2 to 21.9 d, with a mean of 18.2 d. Root and shoot mass ranged from 0.07 to 0.27 g/plot and 0.07 to 0.24 g/plot, respectively. Correlations among the traits measured were favorable, permitting simultaneous improvement. The rankings between the warm and cold environments were significantly correlated (r = 0.67***), indicating that some entries that performed well under low temperatures also performed well under warm conditions.
Louise Ferguson and R. Buchner
Currently, the California pistachio industry relies upon 4 rootstock; Pistacia integerrima, P. atlantica and 2 different hybrids of P. atlantica × P. integerrima. Although observations have been made, no trials have established the relative cold tolerances of these rootstock. The above four rootstock were planted in June, 1989, in Shasta County, California. Each rootstock was repeated once within the 100 replications of the randomized complete block experimental design. The trees were unbudded. The lowest winter temperature of 14°F (-24°C) occurred in February, 1990. When the trees were rated for damage in April, 1990, P. atlantica displayed only 3% mild tip burn damage compared to 56% tip burn for P. atlantica × P. integerrima (commercially known as UCB #1), 79% tip burn for P. atlantica × P. integerrima (commercially known as Pioneer Gold I) and 95% severe dieback for P. integerrima. Five superior P. integerrima rootstooks, with no damage, were identified.
Na-Hyun Song and Yeh-Jin Ahn
chinensis L.) was not expressed in the absence of stress but was induced under a cold stress condition (2 °C, 6 h; Jiang et al., 2009 ). These studies suggest that at least some plant sHSPs may confer cold tolerance. A number of studies have shown that