Photosynthetic Characteristics of Three Asparagus Cultivars Differing in Yield

Abstract

The physiological basis of yield in asparagus (Asparagus offincinails L.) is poorly understood, but some reports have inferred a link between lateral fern photosynthesis (A) and annual spear yield. Gas exchange measurements were made on single lateral ferns of mature asparagus plants in the field and younger, potted plants. Among three cuitivars with different levels of yield, the light-saturated rate ofphotusynthesis (A~t) was positively associated with crop yield in both sets of plants. There was a highly significant correlation between Ant and stumatal conductance (gs). A~l also increased with fern nitrogen, chlorophyll, and soluble protein concentrations across the cultivars. These data imply that differences in both gs and photosynthetic capacity contributed to the variation in A~at, and this was supported by AJCI (internal CO2 concentration) analysis. Variation in photosynthetic capacity was related to genotypic differences in cladophyli diameter and thus the content (per unit sudace area) of photosynthetic biochemical constituents and, possibly, mesophyli resistance to COz diffusion. The possibility of genotypic variation in other photosynthetic parameters was also noted. It is concluded that fern A~l might be a predictor of yield in asparagus, and of potential use in early selection for breeding, but confirmation of such a relationship requires investigation in a wider range of genotypes.

Drought stress induced changes in some organic substances in nodules and other plant parts of two potential legumes differing in salt tolerance

“…Such a positive association between growth and photosynthetic capacity has also been found in a number of species, e.g. durum wheat (El-Hafid et al, 1998;Gummuluru et al, 1989), spring wheat (Johnson et al, 1987;Martin and RuizTorres, 1992), tobacco (Van Rensburg and Kruger, 1993), sorghum (Peng and Krieg, 1992), cotton (Cornish et al, 1991;Pettigrew and Meredith, 1994), and asparagus (Faville et al, 1999).…”

Does exogenous application of salicylic acid through the rooting medium modulate growth and photosynthetic capacity in two differently adapted spring wheat cultivars under salt stress?

“…Stomatal conductance, transpiration rate, leaf area and length of grain filling period were all higher in high yielding cultivars. In asparagus, Faville et al (1999) found that rate of photosynthesis had a positive association with the crop yield. Thus, final biological or economic yield can be increased by increasing the rate of photosynthesis.…”

An investigation of differences in fruit yield and components contributing to increased fruit yield in Japanese and Dutch tomato cultivars

“…Total plant productivity depends on the appropriate export of carbon from source leaves, which, in turn, depends on the carbon assimilation rate (Komor 2000). Some researchers have recently reported cultivar differences in photosynthetic rates, and a positive correlation has been observed between photosynthetic rate and yield among cultivars in some crops, such as tomato (Higashide and Heuvelink 2009;Matsuda et al 2011a;van der Ploeg et al 2007), asparagus (Bai and Kelly 1999;Faville et al 1999), potato (Tekalign and Hmmes 2005), rice (Sasaki and Ishii 1992;Sasaki et al 1996), and cotton (Stiller et al 2005). Transpiration rates of both cultivars decreased drastically from 40 DAF, caused by a decrease in stomatal conductance ( Figure 2B, C).…”