Some physiological aspects of growth and yield in wheat crops: a comparison of a semidwarf and a standard height cultivar

Abstract

A field experiment showed the semidwarf cultivar Penjamo 62 to outyield the taller Australian cultivar Gamenya at nitrogen levels up to 896 kg N ha-1. This was attributed primarily to a faster rate of grain growth particularly in the later stages. Lodging resistance of Penjamo 62 accounted for only 16-58 per cent of the differences observed at the lower nitrogen levels. Although these two cultivars showed only small differences in both photosynthesis and in the duration of photosynthetic activity of microplots in the greenhouse, large differences in the efficiency of utilization of post-anthesis photosynthesis for grain production were inferred from growth analysis. Moreover, grain growth of Penjamo 62 was far more sensitive to a post-anthesis drought than that of Gamenya, even though similar levels of water deficit and reductions in photosynthesis were recorded in microplots of both cultivars.

Pyramiding of two bacterial blight resistance and a semidwarfing gene in Type 3 Basmati using marker-assisted selection

“…The sd-1 gene confers semidwarf stature, improves lodging tolerance (Pinthus 1973) and harvest index (Walcott and Laing 1976). The semidwarf gene sd-1 has been mapped on chromosome 1 of rice and cloned (Monna et al 2002;Sasaki et al 2002) and a perfect PCR based marker 'h' has been developed (Ellis and Spielmeyer 2002).…”

Semidwarf ( sd-1 ), “green revolution” rice, contains a defective gibberellin 20-oxidase gene

“…Its recessive character results in a shortened culm with improved lodging resistance and a greater harvest index, allowing for the increased use of nitrogen fertilizers (1,2). The sd-1 gene was first identified in the Chinese variety Dee-geo-woo-gen (DGWG), and was crossed in the early 1960s with Peta (tall) to develop the semidwarf cultivar IR8 (3), which produced record yields throughout Asia and formed the basis for the development of new high-yielding, semidwarf plant types (3).…”

Development of a SCAR Marker for Discrimination of a Thai Jasmine Rice (<i>Oryza sativa</i> L. cv. KDML105) Mutant, BKOS6, and Associated with Purple Color Trait in Thai Jasmine Rice-Related Varieties

“…Semi-dwarfism is one of the most important traits deployed in modern rice breeding. Its semidwarf character results in a shortened culm with improved lodging resistance, allowing for the increased use of nitrogen fertilizers and a greater harvest index [6,7]. Both photoperiod insensitivity and early-flowering allow plants to start producing flowers quickly in any time of a year, and have been appeared to give high yield potential.…”