Organic selection may improve yield efficiency in spring wheat: A preliminary analysis.

Abstract

Organic spring wheat (Triticum aestivum L.) breeding programs have been initiated, yet yield efficiency and N economy research is limited. We evaluated the performance of advanced lines selected from an organic breeding program initiated in 2003. Fourteen F 8 and F 9 lines in 2009 and 11 lines in 2010 were compared with commercial (check) cultivars. Field experiments were conducted under organic management at four site-years in Manitoba and Saskatchewan. Combined analysis showed no difference in biomass accumulation between organic lines and check cultivars; however, harvest index and grain yield were greater in organic lines compared with the checks. Organic lines were shorter than check cultivars, but yield efficiency, defined as kernel number per unit of crop biomass at anthesis, was higher (P < 0.05). Kernel mass was also greater for organic lines. Biomass N uptake was similar for organic lines and check cultivars, although total uptake of N into grain was greater for organic lines. The average grain protein content of organic lines was significantly lower than the check cultivars. This study demonstrated that improved yield under organic management was because of better assimilate partitioning, both at anthesis and crop maturity, for organically selected genotypes.

Evaluation of Lines from a Farmer Participatory Organic Wheat Breeding Program

“…Seed mass was significantly lower for farmer selections than for check cultivars (Table 6). Wiebe et al (2017) observed greater kernel production per unit area of land in organically selected lines compared with conventional check cultivars. Wiebe et al (2017) observed greater kernel production per unit area of land in organically selected lines compared with conventional check cultivars.…”

“…Kernel number per unit area of land, on the other hand, was greater for farmer selections (data not shown), indicating greater sink strength (Entz and Fowler, 1990). Wiebe et al (2017) observed greater kernel production per unit area of land in organically selected lines compared with conventional check cultivars. As a Table 6.…”

“…Selection in organic breeding programs has been focused on factors such as early season vigor, the ability to suppress and tolerate weed presence, and efficient N uptake from non-inorganic forms (e.g., manure and N-fixing cover crops). In Manitoba, Kirk et al (2012) observed a 10% yield advantage and higher grain protein content in organically vs. conventionally selected lines from the same crosses, whereas Wiebe et al (2017) observed higher kernel production efficiency in organically selected vs. conventionally bred commercial wheat cultivars. In Manitoba, Kirk et al (2012) observed a 10% yield advantage and higher grain protein content in organically vs. conventionally selected lines from the same crosses, whereas Wiebe et al (2017) observed higher kernel production efficiency in organically selected vs. conventionally bred commercial wheat cultivars.…”

“…In their study of 35 different soft white winter wheat (Triticum aestivum L.) breeding lines, Murphy et al (2007) found that direct selection within organic systems resulted in yields 5 to 31% higher than when the lines were selected in conventional systems. In Manitoba, Kirk et al (2012) observed a 10% yield advantage and higher grain protein content in organically vs. conventionally selected lines from the same crosses, whereas Wiebe et al (2017) observed higher kernel production efficiency in organically selected vs. conventionally bred commercial wheat cultivars. Reid et al (2011) observed that lines which ranked first and second under conventional management ranked 53rd and 21st, respectively, under organic management.…”

Optimizing single irrigation scheme to improve water use efficiency by manipulating winter wheat sink-source relationships in Northern China Plain

“…Bindraban et al [ 43 ] described that sink capacity is the result of biomass at anthesis and grain production efficiency (GPE). Previous studies have also shown that enhanced sink capacity can be achieved by increasing spike dry matter or SPI and GPE [ 44 – 48 ]. In the present research, compared with W U , W J reduced leaf size and LAI, and thus decreased biomass at anthesis, but W J improved the allocation of biomass to spike at anthesis, manifested by a higher SPI and GPE, subsequently increasing sink capacity ( Table 6 ).…”