Seed-yield and yield components response to source–sink ratio in annual and perennial species of Lesquerella (Brassicaceae)

Author: W.J. Masnattaa, D.A. Ravettaa,
Date: May 2011
Abstract: Although the annual Lesquerella fendleri is the prime candidate for the development of a lesquerolic rich oil-seed crop, within this genus there are other species available to breeders, some of which are perennials. However, the feasibility of a perennial crop of Lesquerella is not clear because increases in seed-yield tend to reduce perennially. The objective of this work was to determine the effect of the source–sink ratio on seed yield and yield components in annual and perennial species of Lesquerella. We predicted that (i) due to differences in allocation patterns of annual and perennial species, seed-yield and yield components in perennials would be less affected by the source–sink ratio (higher stability) than in annuals and (ii) since seed-weight has been found to be the most stable yield component in other crops and their wild relatives, most of the variation in seed-yield as a consequence of source–sink ratios would be determined by changes in the number fruits per plant and the number of seeds per fruit. A field experiment was carried out in Chubut, Patagonia Argentina in a complete randomized design with four treatments to examine source–sink relationships in four species of Lesquerella, two annuals (L. angustifolia, L. gracilis) and two perennials (L. pinetorum, L. mendocina). We used either shading (reduction of source) or removal of flowerbuds (reduction of sink) to develop a range of source–sink relationships. All four species showed a similar yield response to source–sink variations. Seed-yield was lower in shaded plants, although the timing of shading influenced this response. Flower-bud removal resulted in a significant increase in seed-yield. Seed-yield differences among source–sink treatments were best explained by changes in the number of fruits per plant than by the number of seeds per fruit. Source–sink manipulations had no affect on seed weight. Flower-bud removal significantly increased the number of fruits per plant in all species except for L. mendocina. The number of seeds per fruits increased only in L. pinetorum. Our results show that carbon stored during pre-anthesis plays a key role in reproduction both in annual and perennial Lesquerella. The increase in the seed-yield components found with bud removal could potentially reduce longevity in perennial species. The results also show that the number of fruits per plant is a good proxy for seed-yield within a species.
Source: www.sciencedirect.com/science/article/pii/S0926669011001178

Relationships between reproductive output, morpho-physiological traits and life span in Lesquerella (Brassicaceae)

This research evaluates the reproductive output and ecophysiological traits in annual and perennial Lesquerella (commonly known as Bladderpod). The plants showed a gradation in traits that provide drought-tolerance or high productivity. Perennial species showed drought tolerance traits whereas other species showed intermediate values of traits, related with productivity and drought tolerance.

Author: Luciana González-Paleo, Damián Ravetta
Date:
 March 2011
Affiliation: Industrial Crops and Products
Abstract: The development of perennial industrial crops could contribute to increase agriculture sustainability and yield stability in arid environments. Since perennial plants allocate resources preferentially to perpetuation and to structural and functional characters that provide drought tolerance, they tend to have lower reproductive output (yield) than their congeneric annuals. Four species of Lesquerella native to arid regions were evaluated to understand the relationships between reproduction, drought tolerance, and their association with the plant’s life span. We assessed the following set of characters (defined as plant strategies): phenology, gas exchange, specific leaf area, leaf area ratio, total biomass and biomass allocation. Annual (Lesquerella gracilis and Lesquerella angustifolia) and perennial (Lesquerella mendocina and Lesquerella pinetorum) species were compared under water limiting conditions. Within this set of species differences in structural and functional characters were observed… Read full research article here.

Lesquerella : New crop development and commercialization in the U.S.

Author: D.A. Dierig et al
Date:
 January 2011
Affiliation: Industrial Crops and Products
Abstract: While Lesquerella fendleri Gray (Wats.) is not yet a commercial crop, its history serves as a model for new crop development. The most important characteristic is the absence of any significant biological barriers to commercialization. Other potential crops may have valuable, high-demand products but possess traits difficult to overcome such as seed shattering or poor yield capacity. Lesquerella has a distinctive plant architecture that is conducive to seed productivity under a variety of conditions, and the trait could be further exploited. The plant also has high amounts of within-species and interspecific genetic diversity allowing breeding improvements in traits including oil quantity and quality. The unique seed oil is predominately composed of a hydroxy fatty acid, lesquerolic acid (C20:1OH), that is similar to ricinoleic acid (C18:1OH) found in castor oil. Improvements in agronomics will help increase seed yields, water use efficiency, while reducing crop production costs. New tools offered by remote sensing will help plant breeders and growers assess crop development. Defining herbicides and obtaining registrations for use in lesquerella appears to be the biggest obstacle for commercialization of this crop. The improvements in agronomics, breeding, genetics, and the expansion of new markets started in the 1980’s, and has made lesquerella a viable potential crop that could utilize thousands of hectares in arid climates of the world provided research continues.

Read full article here. 

Michigan State works to advance perennial wheat

Michigan State – with the $1 million grant that it has recently won is joining the well-know Washington State University and The Land Institute to create a line perennial grains. Success at Michigan State and these other institutions has been resonating with farmers to save them time, money and resources. 

Author: James Prichard, Associate Press
Date: September 2009

As Steve Culman squatted in the southwestern Michigan farm field, he used his left hand to gently clasp several dead wheat stalks still in the ground, then pointed with his right toward something remarkable near the bottom of them.

There were new sprouts of wheat, emerging shortly after the summer harvest.

Culman is a researcher at Michigan State University, which recently won a four-year $1 million grant from the U.S. Department of Agriculture to further the development of a new type of wheat that would help reduce soil erosion while saving growers money, time and labor.

Read the full story here. 

MSU professor explores perennial wheat crops

Dr. Sieg Snapp, thanks to a four-year, million dollar U.S. Department of Agriculture organic research grant is able to conduct more research regarding agronomic management and practical aspects of variety development of perennial grains at Michigan State University. 

Author: Laura Probyn
Date:
 July 2009

Every time a farmer plants a cash crop, he or she makes a substantial investment of money, time and labor resources. But what if that crop wasn’t something that had to be planted every year, but instead, sprouted out of the ground each spring and was ready for a summer harvest?

Sieg Snapp, associate professor of crop and soil sciences at the Kellogg Biological Station, Michigan State University, is addressing that question. She’s conducting this work thanks to a four-year, million dollar U.S. Department of Agriculture organic research grant.

Her team is studying the possibilities for developing perennial wheat as a crop for environmentally friendly agricultural production. Team members include Scott Swinton, MSU professor of agriculture, food and resource economics; Vicki Morrone, MSU outreach specialist; Janet Lewis, MSU wheat breeder; Michigan farmers; and colleagues at Washington State University. Their work builds on research that leads to a new type of perennial grain crop. Read full story here. 

 

Perennial wheat: the next frontier

Author: Dr. Gio Braidotti
Date:
 January 2011
Affiliation: GRDC
Abstract: The idea that cereals such as bread wheat, rice and sorghum can be transformed from high-input annuals to more resilient perennial plants has obvious appeal. Here, in theory, would be a crop that could be harvested over several seasons, while also providing biomass for forage and environmental services, such as protection from wind erosion and dryland salinity.
Source: http://www.grdc.com.au/Media-Centre/Ground-Cover-Supplements/Ground-Cover-Issue-91-Capacity-Building-supplement/Perennial-wheat-the-next-frontier

Permanganate Oxidizable Carbon Reflects a Processed Soil Fraction that is Sensitive to Management

Author: Steve Culman et al
Date:  March–April 2012
Abstract: Permanganate oxidizable C (POXC; i.e., active C) is a relatively new method that can quantify labile soil C rapidly and inexpensively. Despite limited reports of positive correlations with particulate organic C (POC), microbial biomass C (MBC), and other soil C fractions, little is known about what soil fractions POXC most closely re!ects. We measured POXC across a wide range of soil types, ecosystems, and geographic areas (12 studies, 53 total sites, n = 1379) to: (i) determine the relationship between POXC and POC, MBC and soil organic C (SOC) fractions, and (ii) determine the relative sensitivity of POXC as a labile soil C metric across a range of environmental and management conditions.
Source: SSSAJ: Volume 76: Number 2

From Jude Maul

I am currently attending an intensive eExtension writing group in Annapolis, MD.  We were each invited to submit at least one extension write-up on grain production.  I have started writing a short article “Introduction and Current Research in Perennial Wheat”.  If anyone has references, self-references (with a little blurb about the work you are citing), preliminary data and any-other information you would like to contribute.  If you contribute to writing or editing then you can be listed as an author.  The article will eventually be published on eXtension (www.extension.org/) and can considered as an extension publication.  Please send me any information that may be useful for this write-up, to Jude.maul@gmail.com
Jude Maul
Research Ecologist
USDA-ARS
Sustainable Agriculture Systems Lab
Building 001, rm 140
Beltsville, Maryland 20770