5 things to consider before buying hybrid seeds

Hybrid plants are a crossing between two selected parent plants achieved via controlled pollination  (see how are plants propagated). The seeds produced by this process are called F1 or F1 Hybrids. These hybrids will exhibit very specific qualities. Hybrids have quickly come to dominate the seed market. However, in spite of their increased market presence of hybrids, there are several factors to be considered. They can be summarized as follows:

Loss of Genetic Diversity

The massive shift to the use of hybrids has resulted in a severe reduction in seed varieties. Between 1984 and 1987, 54 of the 230 American and Canadian mail-order seed companies went out of business. With their closure, 943 non-hybrid varieties, or approximately 19% of all varieties, were lost. This trend continues based on the evolving demands of the agriculture industry, i.e. extreme consolidation and the globalization of supply chains. However, genetic diversity must be maintained as it is essential to the survival and adaptability of any given species (see crop wild relatives), something that will be increasingly relevant as a result of changes in climate and pest adaptations.

Higher Prices

Hybrid seeds are typically more expensive due to the financial investment required by the seed companies in order to develop new strains. Investment in this respect relates to finding two suitable partner plants and hand-pollination. The higher cost is passed on to growers. Growers who are producing for the market must then pass on the costs to consumers.

Non-saveable Seeds

Seeds from hybrids cannot be saved as the offspring will be genetically unpredictable. As a result, growers are forced to purchase new seeds each year. This puts undue financial stress on small-scale growers, which further contributes to the consolidation of the agricultural system. Further consolidation means more extreme shifts to mechanization which requires the use of chemicals that typically harm the environment and erode the relationship between food producer and consumer.

Private Property Rights

Unlike open-pollinated seeds, hybrid seeds are patented. This means that the genetic rights to the plants belong to the company producing the seeds rather than being a public good. With seed companies becoming increasingly consolidated, the power and control continue to become concentrated. In 2007, three companies – Monsanto, Dupont and Syngenta – controlled 47% of the world’s seed market with Monsanto alone controlling one-quarter of the market. Since that time, Monsanto has merged with Bayer, Dupont merged with Dow, and Syngenta merged with ChemChina. These mergers resulted in the development of an extremely powerful oligarchy that has a stronghold on the world’s seed market. This chokehold means diminished autonomy and a world subjected to subversive tactics designed to broaden the companies’ influence in the world’s economy.

Commercial Focus

The hybrid varieties produced are typically designed for commercial growers. Therefore, the primary focus of plant breeders is tolerance for machine harvesting and processing, with flavor and texture being of minimal importance. Likewise, hybrid varieties are designed to ripen uniformly which is not necessarily of benefit to home or smaller producers who seek to extend the growing season over as long of a period as possible.

Sources:

Ashworth, S. (2002). Seed to seed: Seed saving techniques for the vegetable gardener. Decorah, IA: Seed Savers Exchange.
https://extension.illinois.edu/hortihints/0102a.html
https://garden.org/courseweb/course2/week2/page18.htm
http://news.agropages.com/News/NewsDetail—21186.htm

the advantages and disadvantages associated with intercropping

Despite the fact that intercropping has ancient roots, it is only more recently that institutional attention has been paid to this growing method. The majority of formal research to date focuses on large-scale, rural production. Findings show that intercropping has both advantages and disadvantages, which are described in the table below.

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– – – 

  • yield advantage
  • space maximization
  • pest deterrent and weed suppression → decreased pesticide and herbicide use
  • the potential for natural nitrogen use (less runoff)
  • reduced erosion via increased ground cover increased biomass production
  • informal crop insurance (reduced risk of complete crop failure)
  • competition for space, nutrients and sunlight → potential decreases in output
  • integrated management efforts essential
  • higher sowing and harvesting costs (non-machine) → higher labor costs
  • extensive planning required


However, the majority of issues related to intercropping can be overcome with proactive management, albeit harvesting without a machine is a great burden to producers, making the integration of intercropping on a large-scale difficult. Nonetheless, new research in this area is being conducted, and innovative, modular equipment is being developed in order to better facilitate the use of intercropping techniques.

sources:

Lithourgidis, A.; Dordas, C.; Damalas, C. A.;  Vlachostergios, D.N. (2011, April) Annual intercrops: An alternative pathway for sustainable agriculture. Australian Journal of Crop Science, 5(4) Retrieved from https://www.researchgate.net/publication/224934832_Annual_intercrops_An_alternative_pathway_for_sustainable_agriculture
Mousavi, S. R.; Eskandari, H. (2011, January). A General Overview on Intercropping and Its Advantages in Sustainable Agriculture. Applied Environmental Biological Sciences. 1(11). Retrieved from https://www.researchgate.net/publication/220000362_A_General_Overview_on_Intercropping_and_Its_Advantages_in_Sustainable_Agriculture
Sullivan, P. (1998, November). Intercropping Principles and Production Practices. Agronomy Systems Guide.  Retrieved from http://www.iatp.org/files/Intercropping_Principles_and_Production_Practi.htm
Wiley, R.W. and Rao, R.M. (1980, April) A Competitive Ratio for Quantifying Competition Between Intercrops. Experimental Agriculture, 16(02). Retrieved from https://www.researchgate.net/publication/231898671_A_Competitive_Ratio_for_Quantifying_Competition_Between_Intercrops

Zeman, F. (2012) Metropolitan sustainability: understanding and improving the urban environment. Oxford, Cambridge, Philadelphia, Delhi: Woodhead Publishing Limited

an introduction to intercropping

Intercropping is a growing method rooted in ecological diversity. In intercropped systems, two or more component crops are grown together for a given growing period. There are currently four types of intercropping systems:

  1. Strip: crops are grown simultaneously in independent rows within the same field
  2. Row: crops are grown together simultaneously and a minimum of one crop is planted in a row
  3. Mixed: there is no specific order to the crops
  4. Relay: the growing system is dependent on the lifecycle stage of the intercropped plants. Typically, the second crop in the intercropping schedule is planted after the first crop reaches the reproductive stage and before it reaches peak maturity
types-of-intercropping
Types of Intercropping, Source: own, Adapted from Mousavi and Eskandari (2011)

Regardless of the intercropping pattern selected, the plants grown together should be complementary in nature in that they have different “rooting abilities, canopy structure, height and nutrient requirements” which produce a yield advantage. This occurs when resources that could not be utilized by a single crop are utilized by an additional crop growing in the same space.  One of the best-known examples of intercropping is the three sisters method developed by Native Americans in the United States, where Maize, pole beans and winter squash are grown together. The Maize provides a form for the beans to climb and shades the squash. The beans stabilize and fix nitrogen for the Maize plants. The squash provides ground cover, effectively maintaining moisture levels and suppressing weeds.

In order to develop an advantageous intercropped system, five fundamental principles must be adhered to:  

  1. A detailed plan must be developed, including an understanding of the characteristics of the component crops
  2. Crops must be timely sown
  3. Adequate fertilizer must be applied at the appropriate time
  4. A weed and pest strategy must be in place
  5. Harvesting must be efficient

If the wrong types of plants are grown together or the spacing is incorrect, the output will decrease.  To determine whether an intercropped system is effective, the land equivalent ratio [LER] is typically used, where:  (INTERCROP 1 / PURE YIELD 1) / (INTERCROP 2 / PURE YIELD 2). Results > 1.0 indicate an advantageous pairing. Results < 1.0 indicate a disadvantageous pairing.

sources:

Lithourgidis, A.; Dordas, C.; Damalas, C. A.;  Vlachostergios, D.N. (2011, April) Annual intercrops: An alternative pathway for sustainable agriculture. Australian Journal of Crop Science, 5(4) Retrieved from https://www.researchgate.net/publication/224934832_Annual_intercrops_An_alternative_pathway_for_sustainable_agriculture
Mousavi, S. R.; Eskandari, H. (2011, January). A General Overview on Intercropping and Its Advantages in Sustainable Agriculture. Applied Environmental Biological Sciences. 1(11). Retrieved from https://www.researchgate.net/publication/220000362_A_General_Overview_on_Intercropping_and_Its_Advantages_in_Sustainable_Agriculture
Sullivan, P. (1998, November). Intercropping Principles and Production Practices. Agronomy Systems Guide.  Retrieved from http://www.iatp.org/files/Intercropping_Principles_and_Production_Practi.htm
Wiley, R.W. and Rao, R.M. (1980, April) A Competitive Ratio for Quantifying Competition Between Intercrops. Experimental Agriculture, 16(02). Retrieved from https://www.researchgate.net/publication/231898671_A_Competitive_Ratio_for_Quantifying_Competition_Between_Intercrops

Zeman, F. (2012) Metropolitan sustainability: understanding and improving the urban environment. Oxford, Cambridge, Philadelphia, Delhi: Woodhead Publishing Limited

10 common plant disease symptoms

Loss of Turgor Pressure (decrease in water pressure within plant cell walls)
Causes: abiotic factors, bacteria, fungi, nematodes, insects
Examples: Ralstonia solanacearum, Verticillium dahliae, Bursaphelenchus xylophilus

2776528_orig
Photo credit: biology4isc.weebly.com

 

Enations (scaly leaflike structures that lack a vascular system)
Causes: viruses
Examples: Cherry raspberry leaf virus, Pea enation mosaic virus

tn2001006f10
Photo credit:  fftc.agnet.org

 

Stunting (dwarfing or loss of vigor)
Causes: viruses, phytoplasma, fungi, nematodes
Examples: Rhizoctonia, Strawberry lethal yellows

16852_original
Photo credit: ucanr.edu/

 

Witches’ Broom (dense clustering of abnormally small twigs)
Causes: phytoplasma, fungi, insects, mites
Examples: Ash yellows phytoplasma, Sphaerotheca sp.

20140412_stp002_0
Photo credit: economist.com

 

Galls (abnormal growths)
Causes: fungi, nematodes, mites
Examples: Gymnosporangium sabinae, Meloidogyne spp.

galls20on20lime_0
Photo credit: isponature.com

 

Fruit and Seed Deformation (malformed fruit or seeds)
Causes: abiotic factors, viruses, bacteria, fungi, nematodes, insects
Examples: Catfacing tomatoes, Little cherry disease, Spiroplasma citri, Thrips palmi

catfacing_in_tomato
Photo credit: eorganic.info

 

Tumors (aggregates of cells that have multiplied excessively)
Causes: viruses, bacteria
Examples: Agrobacterium tumefaciens, Cryphonectria parasitica

tomato
Photo credit: cals.ncsu.edu

 

Gummosis (oozing of sap from wounds/cankers on fruit trees)
Causes: abiotic factors, bacteria, fungi, insects, injury to the cutting sites
Examples: Pseudomonas syringa, Colletotrichum gloeosporioides

cytospora-perennial-canker_oozing
Photo credit: utahpests.usu.edu

 

Rot (decay)
Causes: bacteria, fungi
Examples: Arruina carotovora, Ralstonia solanacearum, Phomopsis obscurans, Botrytis cinerea

07blossomendrot_lg
Photo credit: clemson.edu

 

Necrosis (death of cells or tissues)
Causes: abiotic factors, viruses, bacteria, fungi, nematodes, insects
Examples: Xanthomonas axonopodis, Fusarium oxysporum, Milbe Tetranychus cinnabarinus

fig2
Photo credit: srs.fs.usda.gov

For more information about plant diseases read:

A Brief Introduction to Plant Diseases

 

question: how is a beautiful lawn the “perfect antithesis of an ecological system”?

PerfectLawnLines1

According to the Barbara Stein, author of Noah’s Garden, a perfect lawn perpetually requires intensive inputs due to the fact that it is completely cut-off from the natural system that would otherwise support it. Additionally, the roots that grow from lawn grass become a “feltlike mat” that is between 2 and 4 inches deep. The tangled roots inhibit the growth of other plants and require large amounts of water input during the hot summer months, as well is 5 “feedings” of nitrogen, phosphorous and/or potassium. With so many inputs, including additional herbicides to remove any potential invaders, the grass grows rapidly which requires that it be cut frequently which in turn encourages the growth of new blades because the plant is never able to flower. In turn, the carrying capacity of the lawn extremely low because there is a lack of biodiversity that is necessary to support fauna.

As grass has evolved to endure grazing it grows sideways below the reach of grazers (or lawnmowers) in order to protect the nodes from consumption and/or destruction and the tillers of the plant grow from the root of the plant, as opposed to the stalk itself. Furthermore, grass is defensive in nature – there is silica in the blades, needled awns in the seeds, and the ability to use leftover nutrients in the roots in order to toughen the cellulose in preparation for the following growing season. There is also an indication that different grasses “green” sequentially as an adaptation to grazers.

As a result of these adaptations, grass looks best in the spring because that is when it is naturally vibrant, has had enough time to “rest” and it is not going against its natural cycle of “tanning” and relaxing in the summer when the weather is hot. It is suggested that an inch of water be applied to lawns along with various fertilizers, herbicides and pesticides in order to maintain the youthful, green spring glow. These inputs need to applied because “lawn” grass engages in C4 photosynthesis which incorporates CO2 with a 4 carbon compound. This form of photosynthesis takes place in the inner cells and occurs much more rapidly than C3 photosynthesis under high light intensity and temperatures because of the compound PEP Carboxylase delivering the CO2 more rapidly. C3 photosynthesis incorporates CO2 with a 3 carbon compound. This form of photosynthesis takes place in the leaves and is most effective in cool and moist locations with normal light conditions.

For more information on the effects of chemical inputs, check out this post on eutrophication.

community gardens discussed and analyzed

“The greatest fine art of the future will be the making of a comfortable living from a small piece of land.”

– Abraham Lincoln

Agriculture is defined as the science, art, and business of cultivating soil, producing crops and raising cattle. It is more commonly referred to as farming. Without it, society as we know it would not exist. It has enabled people to put down roots which provided the means for the world’s population to expand. Unfortunately, it has also been transformed by industrialization into a widely abused system that is dependent on government subsidies and environmentally unsound practices in order to produce food products with less nutritional value and poorer taste. Furthermore, the existing agriculture system is controlled by an increasingly small number of international firms.

However, grassroots efforts and individuals are choosing to look at food in a different way, a way that seems to be able to co-exist with ecosystems. A viable option that has been employed in the past, but since forgotten, is the community garden.

A community garden is any vacant land that is used for growing food and is accessible to community members. Not only do these gardens provide healthy food to demographics that many not otherwise have access, but it improves the overall quality of life in the community by reducing crime, encouraging exercise, and encourages people to have pride in their neighborhood. However, the benefits of community gardens are not limited to the community. Instead, the effects impact the whole ecosystem.

Many community gardens have strict rules about the methods members can employ, and choose to model organic farming methods. Those rules include limiting or banning synthetic pesticides and fertilizers. Some community gardens also ban certain species of plants that have been proven to attract pests or have no predators to limit spreading.

Community gardens limit non-organic pesticides and fertilizers, because of the effects that they can have on human, animal, and environmental health which allows for the natural qualities of soil and the ecosystem to shine.

amendingsoil

Soil is an essential part of the growing environment and without healthy soil, one would not be able to produce healthy plants. Ideal soil for plants is composed of 25% air, 45% minerals, 25% water and 5% organic material. This mix allows for plant roots to efficiently breathe and absorb nutrients and water. However, different plants prefer different mixes of minerals and will tolerate varying degrees of acidity and moisture.

To create ideal soil that is rich in nutrients, well-aerated, and free from disease, many community gardens employ composting methods. Compost is the process of breaking down organic material. The result is a very dark, rich addition to any garden.

Compost is created by putting Nitrogen rich items (greens-vegetable scraps, lawn cuttings, and coffee grounds) and Carbon-rich items (browns-shredded cardboard, sawdust, and leaves) together into a well-ventilated space and mixing with water. The ideal ratio of Carbon to Nitrogen is 25-30:1. This mixture can heat up to 150 degrees from the work of macro and micro-organisms. The increased heat speeds up the breakdown process, and when coupled with Red Wiggler Worms, can reduce the decomposition time to only a few weeks.

Finished compost helps to reduce water use because it is will hold 6X’s more water than traditional soil. It also provides nutrients that would not otherwise be available to plants. This reduces and/or eliminates the need for any non-organic fertilizers, reducing cost and environmental impact while gardeners enjoy similar, if not better results.

Another benefit of compost is that it creates stronger plants, and can help to eliminate the need for pesticides. Pesticides include anything designed to destroy fungus, weed, insect or disease. These synthetic killers are non-discriminatory in their effects, and could just as easily kill family pets as insects. This harm could come from direct consumption, water-run off or from residual traces of chemicals in the soil.

compost 101

To further reduce the needs for pesticides, community gardens encourage and use “beneficial” pests. These are insects that are carnivorous and indigenous to the area. The most popular versions of these bugs are Praying Mantises, spiders, Ladybugs and Lacewings. It must also be noted that one should not introduce too many of one species or too many in general in order to maintain a balance.

When gardens choose not to introduce beneficial pests into the garden, they often choose to use other methods to protect their plants. Covering plants in light-weight netting can deter all insects but does not allow for pollination.

Another option is companion planting, such as putting onions or garlic with almost any plant, or celery with plants in the cabbage family. By planting certain plants together, the smells naturally detract invasive species. Marigolds, nasturtiums, and rosemary are also very pungent smelling and deter many pests.

As in any scenario, some problems arise with community gardens, including issues with existing soil, cultural sensitivities, unfavorable weather and the question of sustainability.

Since community gardens use whatever space is available, and the modern version originated in urban areas where the environmental impact of humans is greater than in rural areas. One of the biggest problems community gardens find is the presence of lead in the soil. Lead is devastating to life and is not easy to remove from soil.

Cultural sensitivities are also difficult to deal with, as they are generally historically rooted. In cities such as Chicago and Detroit, some groups are associating community gardening with slavery. This is difficult to deal with because community gardens are dependent on community involvement.

Weather can also impact the effectiveness of community gardens, especially in cooler climates. To deal with weather problems, community gardens use cold frames and wind tunnels. These structures help to regulate temperature and keep out harsh winds and snows. Sometimes, community gardens will couple these methods with cold hardy plants to lengthen the growing season.

The biggest concern that surrounds community gardens is their capacity to feed a large number of people since the population is not getting smaller and everyone needs to eat. There is a large amount of unused space in cities throughout America, but it is unclear if people are willing to utilize it for food production and put forth the effort needed to transform dilapidated neighborhoods.

While the concept of community gardens is not a new idea, society is in a unique situation that could revitalize their presence in towns and city throughout the country. This revival could help improve ecosystems everywhere, redistribute wealth and resources, encourage and the American agricultural system as a whole, or at least I think so!

For more information, check out this website about the steps needed to start a community garden:

http://www.epa.gov/brownfields/urbanag/steps.htm

sources:

Environmental Working Group. (n.d.) Farming: Farm Subsidies. Retrieved from https://farm.ewg.org/

Pidwirny, Michael. (2013). Soil. Retrieved from http://www.eoearth.org/article/Soil

Runk, David. (2010). Lead, other chemicals taint some urban gardens. Times Union

Smith, Edward C. The Vegetable Gardener’s Container Bible. North Adams: Storey, 2010.

review and analysis of of the benefits, purposes and motivations associated with community gardens in the united states

“The varied purposes and benefits of community gardening make it an ideal interventional strategy for community-based practitioners because myriad goals may be addressed through this approach.”

Community gardening emerged in the United States in the 1890s as, “a means to address urban congestion caused by immigration, economic instability and environmental degradation”. Immigrants, children and the poor were the original targets for the efforts, but economic strife caused by war and the Great Depression resulted in nearly universal participation until later in the century when the industrialization of agriculture resulted in the emergence of convenience foods. It was not until the recession in 2009 that community gardens enjoyed a resurgence (19% increase). This suggests that participation in community gardening activities is correlated with the socio-economic conditions of the time.

Beyond necessity, the five main purpose/concerns that relate to community gardens are:

  • Engaging Youth;
  • Health Benefits (dietary, mental, and physical);
  • Gardener vs. Land Holder Conflicts;
  • Social Capital;
  • Participant Motivations and Perspectives.

Positive outcomes are related to socializing opportunities and experiences. This includes social connections that are formed from accessing resources and developing collaborative efforts with outside organizations like universities, youth programs and health centers. Furthermore, multiple social processes (ex. reciprocity) formed during activities related to community gardening transfer to situations outside of the garden. This strengthens a widespread sense of community. This finding emphasizes that social interactions are imperative to the success and perpetuation of community gardens.

Community gardens have also been identified as a mechanism for individuals and communities to preserve, express and affirm culture. This is accomplished by growing specific foods, designing the gardens to reflect cultural heritage and providing a venue for cultural expression with dances, musical performances and festivals.

Participant motivations include access to fresh and better tasting food, enjoyment of nature, health benefits, opportunities to socialize, to beautify and give back to the community and to support the conservation of green space. Some participate in community gardens as a leisure and/or recreation activity. Others see community gardens as a means for neighborhood beautification and believe that they can serve as a way to revitalize distressed areas. Still, others anecdotally report that community gardens are correlated with a reduction in crime once the garden becomes established. This occurs when garden spaces become identified as safe places for individuals and families – especially those who otherwise lack access to open spaces – come together.

The fight for the right to public land use has given participants an opportunity to participate in local politics for the first time. This often occurred when there was an issue of land-use rights. In many of these cases, this conflict served as a means for instigating organization and mobilization of community members. Oftentimes, these individuals would not otherwise interact.

Finally, it was found that in many areas gardeners choose to donate a portion of their produce, typically to senior citizens, the homeless or poor individuals and families which works to improve food access networks for the community as a whole. This indicates that when people create something, they want to share it with the world.

Draper, C., & Freedman, D. (2010). Review and Analysis of the Benefits, Purposes, and Motivations Associated with Community Gardening in the United States. Journal Of Community Practice, 18(4), 458-492.