protected cultivation ( Wahid et al., 2007 ). Therefore, breeding cucumber cultivars with thermostability is a useful strategy for improving the heat tolerance of plants (Wahid et al., 2007). Furthermore, the identification and characterization of genes
response to heat stress under elevated CO 2 with an aim to further understand metabolic mechanisms for elevated CO 2 enhancement of heat tolerance in C 3 perennial grass species. Materials and Methods Plant materials and growth conditions. Sod pieces of
application of GABA has been found to enhance plant tolerance to abiotic stresses, such as chilling tolerance in peach fruit [ Amygdalus persica ( Shang et al., 2011 )], heat tolerance in rice seedlings [ Oryza sativa ( Nayyar et al., 2014 )], and drought
the superoxide radical to H 2 O 2 ; peroxidase (POD); and catalase (CAT) that break down H 2 O 2 to water ( Smirnoff, 1993 ). Superior heat tolerance in warm-season species has been attributed to more efficient C 4 photosynthesis metabolism relative
Net CO2 assimilation (A), evapotranspiration (ET), and stomatal conductance (g s) were determined in two experiments for 14 and 18 raspberry (Rubus sp.) genotypes, respectively, grown in 4-L containers and exposed to 35 °C daytime temperatures 2 weeks and 4 weeks after placement in growth chambers. Measurements were taken on two successive leaves on the same primocane between the third and seventh node (≈75% to 85% of full leaf expansion). In Expt. 1, selections from Louisiana exhibited higher A (3.10-5.73 μmol·m-2·s-1) than those from Oregon (0.50-2.65 μmol·m-2·s-1). In Expt. 2, the genotype × time interactions were nonsignificant, and time of measurement did not affect A or ET (P ≤ 0.05). Assimilation ranged from 2.08 to 6.84 μmol·m-2·s-1 and varied greatly among genotypes, indicating that diverse A levels exist at high temperatures in raspberry germplasm. NC 296, a selection of R. coreanus Miq. from China, and `Dormanred', a southern-adapted raspberry cultivar with R. parvifolius Hemsl. as a parent, had the highest A rates. Evapotranspiration and g s did not differ among genotypes. Average g s for all genotypes declined from 234 mmol·m-2·s-1 in week 2 to 157 mmol·m-2·s-1 in week 4. Our findings, coupled with plant performance under hot conditions, can be used to identify potential parental raspberry germplasm for breeding southern-adapted cultivars.
-tolerant ( Swift, 2008 )], Edkawi LA2711 [unknown heat tolerance, salt-tolerant], and LA1310 [cherry tomato]} were compared. Seed stocks were obtained from the C.M. Rick Tomato Genetics Resource Center at the University of California, Davis. Seeds were propagated
enzyme mediated integration (REMI) mutant, which has a non-pathogenic lifestyle in tomato ( Redman et al., 1999 ). C. protuberata isolate Cp4666D was isolated from plants in geothermal soils and confers heat tolerance ( Redman et al., 2002 ) and CpVF is
roles in heat tolerance. In creeping bentgrass, cultivar differences in heat tolerance were shown to be associated with variations in antioxidant enzyme activities ( Liu and Huang, 2000 ). Park et al. (1997) showed that after heat shock (and expression
Abstract
Heat resistance of aspen (Populus tremuloides) leaves was assessed by stressing leaf discs in vitro and measuring electrolyte leakage. Leaves were obtained from trees growing at elevations of 1960, 2195, and 2454 m. Heat tolerance was greatest in leaf samples from trees growing at the lowest site. Trees propagated from these sites and grown at 1520 m for 2 years showed some increase in heat tolerance, but apparent ecotypic differences persisted.
produces large funnel-shaped, bright yellow, fragrant flowers that compliment its glossy green, pinnately compound leaves. Tecoma ‘Mayan Gold’ was selected as a potential new annual patio flowering crop as a result of its compact nature, drought and heat